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Sample records for feeding spodoptera littoralis

  1. Herbivore-induced maize leaf volatiles affect attraction and feeding behavior of Spodoptera littoralis caterpillars.

    PubMed

    von Mérey, Georg E; Veyrat, Nathalie; D'Alessandro, Marco; Turlings, Ted C J

    2013-01-01

    Plants under herbivore attack emit volatile organic compounds (VOCs) that can serve as foraging cues for natural enemies. Adult females of Lepidoptera, when foraging for host plants to deposit eggs, are commonly repelled by herbivore-induced VOCs, probably to avoid competition and natural enemies. Their larval stages, on the other hand, have been shown to be attracted to inducible VOCs. We speculate that this contradicting behavior of lepidopteran larvae is due to a need to quickly find a new suitable host plant if they have fallen to the ground. However, once they are on a plant they might avoid the sites with fresh damage to limit competition and risk of cannibalism by conspecifics, as well as exposure to natural enemies. To test this we studied the effect of herbivore-induced VOCs on the attraction of larvae of the moth Spodoptera littoralis and on their feeding behavior. The experiments further considered the importance of previous feeding experience on the responses of the larvae. It was confirmed that herbivore-induced VOCs emitted by maize plants are attractive to the larvae, but exposure to the volatiles decreased the growth rate of caterpillars at early developmental stages. Larvae that had fed on maize previously were more attracted by VOCs of induced maize than larvae that had fed on artificial diet. At relatively high concentrations synthetic green leaf volatiles, indicative of fresh damage, also negatively affected the growth rate of caterpillars, but not at low concentrations. In all cases, feeding by the later stages of the larvae was not affected by the VOCs. The results are discussed in the context of larval foraging behavior under natural conditions, where there may be a trade-off between using available host plant signals and avoiding competitors and natural enemies.

  2. Effect of the Extracts of the Spiderflower, Cleome arabica, on Feeding and Survival of Larvae of the Cotton Leafworm, Spodoptera littoralis

    PubMed Central

    Ladhari, Afef; Laarif, Asma; Omezzine, Faten; Haouala, Rabiaa

    2013-01-01

    Aqueous and organic (hexane, chloroform, and methanol) extracts of siliquae, stems and leaves, and seeds of Cleome arabica L. (Brassicales: Capparidaceae) were evaluated in the laboratory for their antifeeding and insecticidal effect on larvae of the cotton leafworm, Spodoptera littoralis (Boisduval) (Lepidoptera, Noctuidae), using a leaf dipping bioassay with castor bean, Ricinus communis L. (Malpighiales: Euphorbiaceae), leaf discs. The polar extracts caused significant mortality. At the highest dose, C. arabica extracts exhibited significant antifeeding and phagostimulating activities against S. littoralis larvae. Under no-choice conditions, the methanol extract of siliquae was the most active, and the antifeedant index calculated over 24 hr for 3rd instar larvae varied significantly from 16 to 37%. Using nutritional indices, it was established that there was a significant decrease in growth rate concomitant with a reduction in consumption. These results suggest the presence of anti-feeding and/or toxic substances in the extracts that may be useful in developing bio-insecticides based on C. arabica extracts for use in integrated pest management of leafworm and other agricultural pests. PMID:23906290

  3. Effects of Feeding Spodoptera littoralis on Lima Bean Leaves. I. Membrane Potentials, Intracellular Calcium Variations, Oral Secretions, and Regurgitate Components1

    PubMed Central

    Maffei, Massimo; Bossi, Simone; Spiteller, Dieter; Mithöfer, Axel; Boland, Wilhelm

    2004-01-01

    Membrane potentials (Vm) and intracellular calcium variations were studied in Lima bean (Phaseolus lunatus) leaves when the Mediterranean climbing cutworm (Spodoptera littoralis) was attacking the plants. In addition to the effect of the feeding insect the impact of several N-acyl Glns (volicitin, N-palmitoyl-Gln, N-linolenoyl-Gln) from the larval oral secretion was studied. The results showed that the early events upon herbivore attack were: a) a strong Vm depolarization at the bite zone and an isotropic wave of Vm depolarization spreading throughout the entire attacked leaf; b) a Vm depolarization observed for the regurgitant but not with volicitin {N-(17-hydroxy-linolenoyl)-Gln} alone; c) an enhanced influx of Ca2+ at the very edge of the bite, which is halved, if the Ca2+ channel blocker Verapamil is used. Furthermore, the dose-dependence effects of N-acyl Gln conjugates-triggered influx of Ca2+ studied in transgenic aequorin-expressing soybean (Glycine max) cells, showed: a) a concentration-dependent influx of Ca2+; b) a configuration-independent effect concerning the stereochemistry of the amino acid moiety; c) a slightly reduced influx of Ca2+ after modification of the fatty acid backbone by functionalization with oxygen and; d) a comparable effect with the detergent SDS. Finally, the herbivore wounding causes a response in the plant cells that cannot be mimicked by mechanical wounding. The involvement of Ca2+ in signaling after herbivore wounding is discussed. PMID:15051862

  4. Determination and analysis of the genome sequence of Spodoptera littoralis multiple nucleopolyhedrovirus

    USDA-ARS?s Scientific Manuscript database

    The Spodoptera littoralis multiple nucleopolyhedrovirus (SpliMNPV), a pathogen of the Egyptian cotton leaf worm Spodoptera littoralis, was subjected to sequencing of its entire DNA genome and bioassay analysis comparing its virulence to that of other baculoviruses. The annotated SpliMNPV genome of...

  5. Development and validation of real-time PCR tests for the identification of four Spodoptera species: Spodoptera eridania, Spodoptera frugiperda, Spodoptera littoralis, and Spodoptera litura (Lepidoptera: Noctuidae).

    PubMed

    Van de Vossenberg, B T L H; Van der Straten, M J

    2014-08-01

    The genus Spodoptera comprises 31 species, 4 of which are listed as quarantine pests for the European Union: Spodoptera eridania (Cramer), Spodoptera frugiperda (Smith), Spodoptera littoralis (Boisduval), and Spodoptera litura (F.). In international trade, the earlier life stages (eggs and larvae) are being intercepted at point of inspection most frequently, challenging the possibilities of morphological identification. To realize a rapid and reliable identification for all stages, we developed and validated four simplex real-time polymerase chain reaction identification tests based on the mitochondrial cytochrome b gene using dual-labeled hydrolysis probes. Method validation on dilutions of extracted DNA of the target organisms showed that low levels of template (up to 0.2-100 pg) can reliably be identified. No cross-reactivity was observed with 14 nontarget Spodoptera and 5 non-Spodoptera species in the specific Spodoptera tests. The tests showed to be repeatable, reproducible (both 100%), and robust. The new Spodoptera tests have proven to be suitable tools for routine identification of all life stages of S. eridania, S. frugiperda, S. littoralis, and S. litura.

  6. Mechanism of entomotoxicity of the plant lectin from Hippeastrum hybrid (Amaryllis) in Spodoptera littoralis larvae.

    PubMed

    Caccia, Silvia; Van Damme, Els J M; De Vos, Winnok H; Smagghe, Guy

    2012-09-01

    Plant lectins have received a lot of attention because of their insecticidal properties. When orally administered in artificial diet or in transgenic plants, lectins provoke a wide range of detrimental effects, including alteration of the digestive enzyme machinery, fecundity drop, reduced feeding, changes in oviposition behavior, growth and development inhibition and mortality. Although many studies reported the entomotoxicity of lectins, only a few of them investigated the mode of action by which lectins exert toxicity. In the present paper we have studied for the first time the insecticidal potential of the plant lectin from Hippeastrum hybrid (Amaryllis) (HHA) bulbs against the larvae of the cotton leafworm (Spodoptera littoralis). Bioassays on neonate larvae showed that this mannose-specific lectin affected larval growth, causing a development retardation and larval weight decrease. Using primary cell cultures from S. littoralis midguts and confocal microscopy we have elucidated FITC-HHA binding and internalization mechanisms. We found that HHA did not exert a toxic effect on S. littoralis midgut cells, but HHA interaction with the brush border of midgut cells interfered with normal nutrient absorption in the S. littoralis midgut, thereby affecting normal larval growth in vivo. This study thus confirms the potential of mannose-specific lectins as pest control agents and sheds light on the mechanism underlying lectin entomotoxicity.

  7. The mustard trypsin inhibitor 2 affects the fertility of Spodoptera littoralis larvae fed on transgenic plants.

    PubMed

    De Leo, F; Gallerani, R

    2002-05-01

    The effects of mustard trypsin inhibitor MTI-2 expressed at different levels in transgenic tobacco lines have been evaluated by feeding the lepidopteran Spodoptera littoralis throughout its larval life. Specific conditions were selected to study the long-term effects of feeding larvae on transgenic plants expressing the inhibitor at various levels. The data obtained led to the establishment of three relevant parameters to be considered during the experimentation: (i) the PI content of the plant lines to be used; (ii) the developmental stage of larvae sensitive to that PI content; (iii) the ratio of MTI-2/proteases sufficient to inhibit gut proteases. The experimental data obtained from feeding S. littoralis larvae using these conditions led to two main results. First, when L2 S. littoralis larvae were fed on high MTI-2 expressing tobacco plants, no effects on larval development were detected but there was a significantly reduced fertility. When the same larvae were fed on low expressing MTI-2 tobacco plants, only a less marked lowering of fertility was observed. Second, after the first generation, no differences in protease activity were observed in insects derived from larvae fed on high or low MTI-2 expressing tobacco lines, suggesting that genetic traits observed in previous studies were not inherited.

  8. Insecticidal activity of some essential oils against larvae of Spodoptera littoralis.

    PubMed

    Pavela, Roman

    2005-12-01

    Thirty-four essential oils were tested for insecticidal activity (fumigation or topical application) against larvae Spodoptera littoralis. Twenty essential oils applied by fumigation were highly toxic to the third instar of S. littoralis larvae. Two essential oils Nepeta cataria and Thuja occidentalis were highly toxic, with LC50< or =10.0 ml/m3. Five essential oils Salvia sclarea, Thymus mastichina, Origanum majorana, Pogostemon cablin and Mentha pulegium were toxic with LC50 between 10.1 and 20.0 l ml/m3. Twenty-three essential oils were highly toxic to the third instar of S. littoralis larvae after topical application. Eight essential oils Mentha citrata, N. cataria, S. sclarea, O. vulgare, O. compactum, Melissa officinalis, T. mastichina, and Lavandula angustifolia were highly toxic with LD50 < or =0.05 microl/larvae.

  9. Compartmentalization of oxidative stress and antioxidant defense in the larval gut of Spodoptera littoralis.

    PubMed

    Krishnan, Natraj; Sehnal, Frantisek

    2006-09-01

    Allelochemicals play important roles in the plant defense against herbivorous insects. They act as feeding deterrents, interfere with digestion and nutrient absorption, and cause production of potentially dangerous oxidative radicals. This study demonstrates that the distributions of oxidative radicals and of the antioxidant enzymes that eliminate them are compartmentalized in the digestive tract of Spodoptera littoralis larvae. Feeding on diets supplemented with the tannic acid (TA), alpha-solanine, and demissidine, respectively, did not affect the rate of food passage through the digestive tract of larvae but 1.25, 2.5, and 5% TA evoked a strong oxidative response. The amount of the superoxide anion in the foregut tissue and content increased up to 70-fold and the titer of total peroxides in the foregut content about 3-fold. This oxidative stress was associated with enhanced carbonyl content in the foregut tissue proteins, indicative of certain tissue deterioration. Extensive foregut damage was probably prevented by elevated activity of the glutathione S-transferase peroxidase. A complex antioxidant response was elicited in the midgut. The activities of superoxide dismutase and catalase increased significantly in the midgut tissue and content, and the activity of ascorbate peroxidase rose in the midgut tissue. The enzymes apparently eliminated oxidative radicals passing to midgut from the foregut with the food bolus and thereby prevented carbonylation of the midgut proteins. We postulate that the generation of oxidative radicals in the foregut and the induction of antioxidant defense in the midgut are controlled processes and that their compartmentalization is an important functional feature of the digestive tract. The glycoalkaloid alpha-solanine and the aglycone demissidine applied at 0.05 and 0.1% concentrations had no effect on any of the examined parameters.

  10. Candidate chemosensory Genes in Female Antennae of the Noctuid Moth Spodoptera littoralis

    PubMed Central

    Jacquin-Joly, Emmanuelle; Legeai, Fabrice; Montagné, Nicolas; Monsempes, Christelle; François, Marie-Christine; Poulain, Julie; Gavory, Frédéric; Walker III, William B.; Hansson, Bill S.; Larsson, Mattias C.

    2012-01-01

    Chemical senses are crucial for all organisms to detect various environmental information. Different protein families, expressed in chemosensory organs, are involved in the detection of this information, such as odorant-binding proteins, olfactory and gustatory receptors, and ionotropic receptors. We recently reported an Expressed Sequence Tag (EST) approach on male antennae of the noctuid moth, Spodoptera littoralis, with which we could identify a large array of chemosensory genes in a species for which no genomic data are available. Here we describe a complementary EST project on female antennae in the same species. 18,342 ESTs were sequenced and their assembly with our previous male ESTs led to a total of 13,685 unigenes, greatly improving our description of the S. littoralis antennal transcriptome. Gene ontology comparison between male and female data suggested a similar complexity of antennae of both sexes. Focusing on chemosensation, we identified 26 odorant-binding proteins, 36 olfactory and 5 gustatory receptors, expressed in the antennae of S. littoralis. One of the newly identified gustatory receptors appeared as female-enriched. Together with its atypical tissue-distribution, this suggests a role in oviposition. The compilation of male and female antennal ESTs represents a valuable resource for exploring the mechanisms of olfaction in S. littoralis. PMID:22904672

  11. Repellent and insecticidal activities of Melia azedarach L. against cotton leafworm, Spodoptera littoralis (Boisd.).

    PubMed

    Farag, Mohamed; Ahmed, Mohamed H M; Yousef, Heba; Abdel-Rahman, Adel A H

    2011-01-01

    A crude acetone extract and oil of ripe fruits from Melia azedarach L. were evaluated against the 2nd and 4th instar larvae of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae). Both oil and extract exhibited highly significant growth inhibition at all concentrations tested, while the oil of M. azedarach recorded higher insecticidal activity against both instars than the crude extract. GC-MS analysis of the oil revealed the presence of linoleic acid methyl ester, oleic acid methyl ester, and free oleic acid as the main components in addition to hexadecanol, palmitic acid, methyl esters of stearic acid and myristic acid. Fatty acids and their esters were not only the main constituents of essential oil from the ripe fruits of M. azedarach, but also mainly responsible for the insecticidal and growth inhibition activity against S. littoralis.

  12. Regulation of Arabidopsis defense responses against Spodoptera littoralis by CPK-mediated calcium signaling

    PubMed Central

    2010-01-01

    Background Plant Ca2+ signals are involved in a wide array of intracellular signaling pathways after pest invasion. Ca2+-binding sensory proteins such as Ca2+-dependent protein kinases (CPKs) have been predicted to mediate the signaling following Ca2+ influx after insect herbivory. However, until now this prediction was not testable. Results To investigate the roles CPKs play in a herbivore response-signaling pathway, we screened the characteristics of Arabidopsis CPK mutants damaged by a feeding generalist herbivore, Spodoptera littoralis. Following insect attack, the cpk3 and cpk13 mutants showed lower transcript levels of plant defensin gene PDF1.2 compared to wild-type plants. The CPK cascade was not directly linked to the herbivory-induced signaling pathways that were mediated by defense-related phytohormones such as jasmonic acid and ethylene. CPK3 was also suggested to be involved in a negative feedback regulation of the cytosolic Ca2+ levels after herbivory and wounding damage. In vitro kinase assays of CPK3 protein with a suite of substrates demonstrated that the protein phosphorylates transcription factors (including ERF1, HsfB2a and CZF1/ZFAR1) in the presence of Ca2+. CPK13 strongly phosphorylated only HsfB2a, irrespective of the presence of Ca2+. Furthermore, in vivo agroinfiltration assays showed that CPK3-or CPK13-derived phosphorylation of a heat shock factor (HsfB2a) promotes PDF1.2 transcriptional activation in the defense response. Conclusions These results reveal the involvement of two Arabidopsis CPKs (CPK3 and CPK13) in the herbivory-induced signaling network via HsfB2a-mediated regulation of the defense-related transcriptional machinery. This cascade is not involved in the phytohormone-related signaling pathways, but rather directly impacts transcription factors for defense responses. PMID:20504319

  13. Identification of plant semiochemicals and characterization of new olfactory sensory neuron types in a polyphagous pest moth, Spodoptera littoralis.

    PubMed

    Binyameen, Muhammad; Anderson, Peter; Ignell, Rickard; Birgersson, Göran; Razaq, Muhammad; Shad, Sarfraz A; Hansson, Bill S; Schlyter, Fredrik

    2014-10-01

    Phytophagous insects use blends of volatiles released from plants to select hosts for feeding and oviposition. To behaviorally analyze complex blends, we need efficient and selective methods for elucidating neuron types, their ligands, and specificity. Gas chromatography-combined single sensillum recordings (GC-SSRs) from antennal olfactory sensilla of female moth, Spodoptera littoralis revealed 38 physiologically active peaks in the headspace volatile blends from both larvae-damaged cotton plants and lilac flowers. Using GC-combined mass spectrometry, 9 new physiologically active compounds were identified from damaged cotton and 11 from lilac compared with earlier electrophysiological studies using antennae of female S. littoralis. We characterized 14 novel classes of olfactory sensory neurons (OSNs). Among these, we found the first 2 ligands for a frequent type of short trichoid sensillum, for which no ligands were identified earlier. By using GC-SSR, a substantial increase in functional classes of OSNs and active compounds, 40% and 34% more, respectively, compared with recent studies using GC-electroantennogram or SSR using single compounds was detected. Compared with the estimated number of corresponding antennal olfactory receptors, the OSN classes now correspond to 83% of a likely maximum. The many specialist OSNs observed may facilitate behavioral confirmation of key plant volatiles in blends. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Targeting the Diuretic Hormone Receptor to Control the Cotton Leafworm, Spodoptera littoralis

    PubMed Central

    Apone, Fabio; Ruggiero, Alessandra; Tortora, Assunta; Tito, Annalisa; Grimaldi, Maria Rosaria; Arciello, Stefania; Andrenacci, Davide; Lelio, Ilaria Di; Colucci, Gabriella

    2014-01-01

    The cotton leafworm, Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae), is one of the most devastating pests of crops worldwide. Several types of treatments have been used against this pest, but many of them failed because of the rapid development of genetic resistance in the different insect populations. G protein coupled receptors have vital functions in most organisms, including insects; thus, they are appealing targets for species-specific pest control strategies. Among the insect G protein coupled receptors, the diuretic hormone receptors have several key roles in development and metabolism, but their importance in vivo and their potential role as targets of novel pest control strategies are largely unexplored. With the goal of using DHR genes as targets to control S. littoralis, we cloned a corticotropin-releasing factor-like binding receptor in this species and expressed the corresponding dsRNA in tobacco plants to knock down the receptor activity in vivo through RNA interference. We also expressed the receptor in mammalian cells to study its signaling pathways. The results indicate that this diuretic hormone receptor gene has vital roles in S. littoralis and represents an excellent molecular target to protect agriculturallyimportant plants from this pest. PMID:25368043

  15. Microbial control of the cotton leafworm Spodoptera littoralis (Boisd.) by Egyptian Bacillus thuringiensis isolates.

    PubMed

    Alfazairy, Ahlam A; El-Ahwany, Amani M D; Mohamed, Eman A; Zaghloul, Heba A H; El-Helow, Ehab R

    2013-03-01

    Four local Bacillus thuringiensis (Bt) isolates that had been serologically identified as Bt var. kurstaki (Btk2, Btk3, and Btk66) and Bt var. mexicanensis (Btm27), in addition to two reference strains (4D20 and 4AC1), were laboratory assayed as microbial control agents against the Egyptian cotton leafworm Spodoptera littoralis (Boisd.). Polymerase chain reaction (PCR) amplification analysis revealed that each of the six experimental strains carries, at least, a cry1 type gene which expresses a protein toxin active against lepidopterous insects. Additionally, PCR amplification results demonstrated that 4D20 and Btk66 contain the Lepidoptera- and Diptera-active cry2 type gene and that Btk66 contains Coleoptera-active cry7 and cry8 genes. Among the six strains, Btk66 and Btm27 were the most promising microbial control agents against S. littoralis. The present findings were the first to report that Btm27 (classified as B. thuringiensis var. mexicanensis) is a very potent microbial control agent against S. littoralis-tested larvae. For more characterization of these two isolates, the sspO gene was investigated as a molecular chronometer. The DNA sequencing results proved that Btk66 and Btm27 carry sspO open reading frames with identical nucleotide sequences, suggesting a strong phylogenetic relationship between the two strains.

  16. Global and Local Modulatory Supply to the Mushroom Bodies of the Moth Spodoptera Littoralis

    PubMed Central

    Sinakevitch, Irina; Sjöholm, Marcus; Hansson, Bill S.; Strausfeld, Nicholas J.

    2014-01-01

    The moth Spodoptera littoralis, is a major pest of agriculture whose olfactory system is tuned to odorants emitted by host plants and conspecifics. As in other insects, the paired mushroom bodies are thought to play pivotal roles in behaviors that are elicited by contextual and multisensory signals, amongst which those of specific odors dominate. Compared with species that have elaborate behavioral repertoires, such as the honey bee Apis mellifera or the cockroach Periplaneta americana, the mushroom bodies of S. littoralis were originally viewed as having a simple cellular organization. This has been since challenged by observations of putative transmitters and neuromodulators. As revealed by immunocytology, the spodopteran mushroom bodies like those of other taxa, are subdivided longitudinally into discrete neuropil domains. Such divisions are further supported by the present study, which also demonstrates discrete affinities to different mushroom body neuropils by antibodies raised against two putative transmitters, glutamate and γ-aminobutyric acid, and against three putative neuromodulatory substances: serotonin, A-type allatostatin, and tachykinin-related peptides. The results suggest that in addition to longitudinal divisions of the lobes, circuits in the calyces and lobes are likely to be independently modulated. PMID:18406668

  17. The Green Gut: Chlorophyll Degradation in the Gut of Spodoptera littoralis.

    PubMed

    Badgaa, Amarsanaa; Büchler, Rita; Wielsch, Natalie; Walde, Marie; Heintzmann, Rainer; Pauchet, Yannik; Svatos, Ales; Ploss, Kerstin; Boland, Wilhelm

    2015-11-01

    Chlorophylls, the most prominent natural pigments, are part of the daily diet of herbivorous insects. The spectrum of ingested and digested chlorophyll metabolites compares well to the pattern of early chlorophyll-degradation products in senescent plants. Intact chlorophyll is rapidly degraded by proteins in the front- and midgut. Unlike plants, insects convert both chlorophyll a and b into the corresponding catabolites. MALDI-TOF/MS imaging allowed monitoring the distribution of the chlorophyll catabolites along the gut of Spodoptera littoralis larvae. The chlorophyll degradation in the fore- and mid-gut is strongly pH dependent, and requires alkaline conditions. Using LC-MS/MS analysis we identified a lipocalin-type protein in the intestinal fluid of S. littoralis homolog to the chlorophyllide a binding protein from Bombyx mori. Widefield and high-resolution autofluorescence microscopy revealed that the brush border membranes are covered with the chlorophyllide binding protein tightly bound via its GPI-anchor to the gut membrane. A function in defense against gut microbes is discussed.

  18. Combinatorial effect of Bacillus thuringiensis kurstaki and Photorhabdus luminescens against Spodoptera littoralis (Lepidoptera: Noctuidae).

    PubMed

    Benfarhat-Touzri, Dalel; Ben Amira, Amal; Ben khedher, Saoussen; Givaudan, Alain; Jaoua, Samir; Tounsi, Slim

    2014-11-01

    Spodoptera littoralis, one of the major pests of many important crop plants, is more susceptible to Bacillus thuringiensis aizawai delta-endotoxins than to those of Bacillus thuringiensis kurstaki. Within the framework of the development of efficient bioinsecticides and the prevention against insect resistance, we tested the effect of mixing B. thuringiensis kurstaki delta-endotoxins and Photorhabdus luminescens cells on S. littoralis growth. The obtained results showed that the growth inhibition of this insect was more effective when B. thuringiensis kurstaki spore-crystal mixture and Photorhabdus luminescens cells were used in combination. Furthermore, this synergism is mainly due to the presence of Cry1Ac, which is one of the three delta-endotoxins that form the crystal of B. thuringiensis kurstaki strain BNS3 in addition to Cry1Aa and Cry2Aa. This work shows a possibility to use B. thuringiensis as a delivery means for Photorhabdus bacteria in order to infect the insect hemocoel and to reduce the risk of developing resistance in the target organism. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Combinatorial effect of Bacillus amyloliquefaciens AG1 biosurfactant and Bacillus thuringiensis Vip3Aa16 toxin on Spodoptera littoralis larvae.

    PubMed

    Ben Khedher, Saoussen; Boukedi, Hanen; Dammak, Mariam; Kilani-Feki, Olfa; Sellami-Boudawara, Tahya; Abdelkefi-Mesrati, Lobna; Tounsi, Slim

    2017-03-01

    Spodoptera littoralis, one of the most serious and destructive agricultural pests in the world, is very susceptible to Vip3 toxin. In order to develop a new efficient bioinsecticide and to prevent the development of resistance by the target pest, insecticidal activity of biosurfactant produced by Bacillus amyloliquefaciens AG1 was evaluated against S. littoralis. Bioassays revealed the susceptibility of the first instar larvae of this pest to AG1 biosurfactant with an LC50 of 245ng/cm(2). Moreover, the histopathology examination of the larval midgut treated by AG1 biosurfactant showed vacuolization, necrosis and disintegration of the basement membrane. Binding experiments revealed that the AG1 biosurfactant recognized three putative receptors located in the brush border membrane vesicles of S. littoralis with sizes of 91, 72 and 64kDa. Competition assays using biotinylated metabolites indicated that AG1 biosurfactant and Vip3Aa16 toxin did not compete for the same S. littoralis receptors. When combined, AG1 biosurfactant and Vip3Aa16 showed an additive effect against S. littoralis larvae. These findings suggested that B. amyloliquefaciens AG1 biosurfactant could be a promising biocontrol agent to eradicate S. littoralis and to prevent resistance development by this pest.

  20. Function and central projections of gustatory receptor neurons on the antenna of the noctuid moth Spodoptera littoralis.

    PubMed

    Popescu, Alexandra; Couton, Louise; Almaas, Tor-Jørgen; Rospars, Jean-Pierre; Wright, Geraldine A; Marion-Poll, Frédéric; Anton, Sylvia

    2013-05-01

    Chemosensory information is crucial for most insects to feed and reproduce. Olfactory signals are mainly used at a distance, whereas gustatory stimuli play an important role when insects directly contact chemical substrates. In noctuid moths, although the antennae are the main olfactory organ, they also bear taste sensilla. These taste sensilla detect sugars and hence are involved in appetitive learning but could also play an important role in food evaluation by detecting salts and bitter substances. To investigate this, we measured the responses of individual taste sensilla on the antennae of Spodoptera littoralis to sugars and salts using tip recordings. We also traced the projections of their neuronal axons into the brain. In each sensillum, we found one or two neurons responding to sugars: one NaCl-responsive and one water-sensitive neuron. Responses of these neurons were dose-dependent and similar across different locations on the antenna. Responses were dependent on the sex for sucrose and on both sex and location for glucose and fructose. We did not observe a spatial map for the projections from specific regions of the antennae to the deutocerebrum or the tritocerebrum/suboesophageal ganglion complex. In accordance with physiological recordings, back-fills from individual sensilla revealed up to four axons, in most cases targeting different projection zones.

  1. The impact of the Bacillus subtilis SPB1 biosurfactant on the midgut histology of Spodoptera littoralis (Lepidoptera: Noctuidae) and determination of its putative receptor.

    PubMed

    Ghribi, Dhouha; Abdelkefi-Mesrati, Lobna; Boukedi, Hanen; Elleuch, Mouna; Ellouze-Chaabouni, Semia; Tounsi, Slim

    2012-02-01

    SPB1 is a Bacillus subtilis strain producing a lipopeptide biosurfactant. The insecticidal activity of this biosurfactant was evaluated against the Egyptian cotton leaf worm (Spodoptera littoralis). It displayed toxicity with an LC(50) of 251 ng/cm(2). The histopathological changes occurred in the larval midgut of S. littoralis treated with B. subtilis SPB1 biosurfactant were vesicle formation in the apical region, cellular vacuolization and destruction of epithelial cells and their boundaries. Ligand-blotting experiments with S. littoralis brush border membrane vesicles showed binding of SPB1 biosurfactant to a protein of 45 kDa corresponding to its putative receptor. The latter differs in molecular size from those recognized by Bacillus thuringiensis Vip3A and Cry1C toxins, commonly known by their activity against S. littoralis. This result wires the application of B. subtilis biosurfactant for effective control of S. littoralis larvae, particularly in the cases where S. littoralis will develop resistance against B. thuringiensis toxins.

  2. Component information is preserved in glomerular responses to binary odor mixtures in the moth Spodoptera littoralis.

    PubMed

    Carlsson, Mikael A; Chong, Kwok Ying; Daniels, Wiltrud; Hansson, Bill S; Pearce, Tim C

    2007-06-01

    Natural odors are often complex mixtures of different compounds. These mixtures can be perceived to have qualities that are different from their components. Moreover, components can be difficult to distinguish within a blend, even if those components are identifiable when presented individually. Thus, odor components can interact along the olfactory pathway in a nonlinear fashion such that the mixture is not perceived simply as the sum of its components. Here we investigated odor-evoked changes in Ca2+ concentration to binary blends of plant-related substances in individually identified glomeruli in the moth Spodoptera littoralis. We used a wide range of blend ratios and a range of concentrations below the level at which glomerular responses become saturated. We found no statistically significant cases where the mixture response was greater than both component responses at the same total concentration (synergistic interactions) and no statistically significant cases where the mixture response was less than either component presented individually (suppressive interactions). Therefore, we conclude that, for the plant mixtures studied, information of their components is preserved in the neural representations encoded at the first stage of olfactory processing in this moth species.

  3. Dynamics of Membrane Potential Variation and Gene Expression Induced by Spodoptera littoralis, Myzus persicae, and Pseudomonas syringae in Arabidopsis

    PubMed Central

    Bricchi, Irene; Bertea, Cinzia M.; Occhipinti, Andrea; Paponov, Ivan A.; Maffei, Massimo E.

    2012-01-01

    Background Biotic stress induced by various herbivores and pathogens invokes plant responses involving different defense mechanisms. However, we do not know whether different biotic stresses share a common response or which signaling pathways are involved in responses to different biotic stresses. We investigated the common and specific responses of Arabidopsis thaliana to three biotic stress agents: Spodoptera littoralis, Myzus persicae, and the pathogen Pseudomonas syringae. Methodology/Principal Findings We used electrophysiology to determine the plasma membrane potential (Vm) and we performed a gene microarray transcriptome analysis on Arabidopsis upon either herbivory or bacterial infection. Vm depolarization was induced by insect attack; however, the response was much more rapid to S. littoralis (30 min −2 h) than to M. persicae (4–6 h). M. persicae differentially regulated almost 10-fold more genes than by S. littoralis with an opposite regulation. M. persicae modulated genes involved in flavonoid, fatty acid, hormone, drug transport and chitin metabolism. S. littoralis regulated responses to heat, transcription and ion transport. The latest Vm depolarization (16 h) was found for P. syringae. The pathogen regulated responses to salicylate, jasmonate and to microorganisms. Despite this late response, the number of genes differentially regulated by P. syringae was closer to those regulated by S. littoralis than by M. persicae. Conclusions/Significance Arabidopsis plasma membranes respond with a Vm depolarization at times depending on the nature of biotic attack which allow setting a time point for comparative genome-wide analysis. A clear relationship between Vm depolarization and gene expression was found. At Vm depolarization timing, M. persicae regulates a wider array of Arabidopsis genes with a clear and distinct regulation than S. littoralis. An almost completely opposite regulation was observed between the aphid and the pathogen, with the former

  4. Antioxidant enzymes in Spodoptera littoralis (Boisduval): are they enhanced to protect gut tissues during oxidative stress?

    PubMed

    Krishnan, Natraj; Kodrík, Dalibor

    2006-01-01

    The Egyptian armyworm Spodoptera littoralis is a polyphagous insect attacking a number of plant species including those belonging to the Solanaceae and Cruciferaceae families. Its digestive physiology must therefore adapt to the food plant to ensure maximum extraction of nutrients with minimum trade-off in terms of growth retardation by pro-oxidant allelochemicals. To investigate this, the caterpillars of S. littoralis were fed on a semi-artificial diet (Manduca Premix-Heliothis Premix) and for 24 h on potato plants (Solanum tuberosum), respectively, at the mature 6th instar, and the levels of oxidative radicals and antioxidant enzymes in their guts were compared. The gut pH, standard redox potential (Eh) and electron availability (pe) revealed that oxidizing conditions prevail which promote oxidation of pro-oxidant allelochemicals in foliage. Oxidative stress in the foregut and midgut tissue and the gut contents was assessed from the generation of superoxide radical, total peroxide content and protein carbonyl content. Antioxidant defense was measured by the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APOX) and glutathione S-transferase peroxidase (GSTpx). A significant (p < 0.001) increase in the superoxide radical production (in foregut tissue, foregut and midgut contents), concomitant with an increase in total peroxide (in foregut contents) and protein carbonyl levels (in foregut and midgut tissue) were noted in larvae fed on the plants in contrast to those fed the semi-artificial diet. Similarly, a significant up-regulation of antioxidant enzymes SOD (in midgut tissues), CAT (in foregut, midgut tissue and contents), APOX (in foregut contents, midgut tissue and contents) and GSTpx (in foregut tissues) was recorded on the plant diet in comparison to the semi-artificial diet. The pro-oxidant allelochemicals in the plant diet are thus eliminated by the insect at the expense of up-regulation of antioxidative enzymes in response

  5. In vivo Pyro-SIP assessing active gut microbiota of the cotton leafworm, Spodoptera littoralis.

    PubMed

    Shao, Yongqi; Arias-Cordero, Erika; Guo, Huijuan; Bartram, Stefan; Boland, Wilhelm

    2014-01-01

    The gut microbiota is of crucial importance for the host with considerable metabolic activity. Although great efforts have been made toward characterizing microbial diversity, measuring components' metabolic activity surprisingly hasn't kept pace. Here we combined pyrosequencing of amplified 16S rRNA genes with in vivo stable isotope probing (Pyro-SIP) to unmask metabolically active bacteria in the gut of cotton leafworm (Spodoptera littoralis), a polyphagous insect herbivore that consumes large amounts of plant material in a short time, liberating abundant glucose in the alimentary canal as a most important carbon and energy source for both host and active gut bacteria. With (13)C glucose as the trophic link, Pyro-SIP revealed that a relatively simple but distinctive gut microbiota co-developed with the host, both metabolic activity and composition shifting throughout larval stages. Pantoea, Citrobacter and Clostridium were particularly active in early-instar, likely the core functional populations linked to nutritional upgrading. Enterococcus was the single predominant genus in the community, and it was essentially stable and metabolically active in the larval lifespan. Based on that Enterococci formed biofilm-like layers on the gut epithelium and that the isolated strains showed antimicrobial properties, Enterococcus may be able to establish a colonization resistance effect in the gut against potentially harmful microbes from outside. Not only does this establish the first in-depth inventory of the gut microbiota of a model organism from the mostly phytophagous Lepidoptera, but this pilot study shows that Pyro-SIP can rapidly gain insight into the gut microbiota's metabolic activity with high resolution and high precision.

  6. In Vivo Pyro-SIP Assessing Active Gut Microbiota of the Cotton Leafworm, Spodoptera littoralis

    PubMed Central

    Shao, Yongqi; Arias-Cordero, Erika; Guo, Huijuan; Bartram, Stefan; Boland, Wilhelm

    2014-01-01

    The gut microbiota is of crucial importance for the host with considerable metabolic activity. Although great efforts have been made toward characterizing microbial diversity, measuring components' metabolic activity surprisingly hasn't kept pace. Here we combined pyrosequencing of amplified 16S rRNA genes with in vivo stable isotope probing (Pyro-SIP) to unmask metabolically active bacteria in the gut of cotton leafworm (Spodoptera littoralis), a polyphagous insect herbivore that consumes large amounts of plant material in a short time, liberating abundant glucose in the alimentary canal as a most important carbon and energy source for both host and active gut bacteria. With 13C glucose as the trophic link, Pyro-SIP revealed that a relatively simple but distinctive gut microbiota co-developed with the host, both metabolic activity and composition shifting throughout larval stages. Pantoea, Citrobacter and Clostridium were particularly active in early-instar, likely the core functional populations linked to nutritional upgrading. Enterococcus was the single predominant genus in the community, and it was essentially stable and metabolically active in the larval lifespan. Based on that Enterococci formed biofilm-like layers on the gut epithelium and that the isolated strains showed antimicrobial properties, Enterococcus may be able to establish a colonization resistance effect in the gut against potentially harmful microbes from outside. Not only does this establish the first in-depth inventory of the gut microbiota of a model organism from the mostly phytophagous Lepidoptera, but this pilot study shows that Pyro-SIP can rapidly gain insight into the gut microbiota's metabolic activity with high resolution and high precision. PMID:24475063

  7. Identification and expression profile of Halloween genes involved in ecdysteroid biosynthesis in Spodoptera littoralis.

    PubMed

    Iga, Masatoshi; Smagghe, Guy

    2010-03-01

    20-Hydroxyecdyone (20E), an active form of ecdysteroid, is the key hormone in insect growth and development. The biosynthesis of ecdysteroid is triggered and under the control of the neuropeptide, prothoracicotropic hormone (PTTH). To date, five cytochrome P450 enzymes, namely Spook (Spo), Phantom (Phm), Disembodied (Dib), Shadow (Sad) and Shade (Shd) related to ecdysteroid biosynthesis, are identified and the character of last four enzymes is well studied in Drosophila melanogaster, Bombyx mori and Manduca sexta. These genes are called Halloween genes and mediate the biosynthesis of 20E from cholesterol. In this study, we extended these works to a major pest insect in agriculture, the cotton leafworm Spodoptera littoralis (Lepidoptera: Noctuidae). We identified the sequence of five Halloween genes, and the converted amino acid sequences were compared with those of other insects. The phylogenetic analysis clearly showed separated clusters of each gene and the evolutional conservation in insects with a high similarity in Lepidoptera. Spo, phm, dib and sad were predominantly expressed in prothoracic glands, and shd was expressed in fat body and Malpighian tubules at the last instar larvae. Spo expression was kept high level between day 2 and day 4 after ecdysis. The expression of phm and dib peaked at day 2, and sad and shd expressions peaked at day 2 and day 4 after ecdysis. In addition, the hemolymph ecdysteroid titer showed a small peak at day 2 and a large peak at day 4 after ecdysis. These results suggest the importance of Halloween genes in ecdysone biosynthesis by prothoracic glands and conversion of ecdysone into 20E by fat body in larval-pupal metamorphosis. (c) 2009 Elsevier Inc. All rights reserved.

  8. Histopathological effects and determination of the putative receptor of Bacillus thuringiensis Cry1Da toxin in Spodoptera littoralis midgut.

    PubMed

    BenFarhat-Touzri, Dalel; Saadaoui, Marwa; Abdelkefi-Mesrati, Lobna; Saadaoui, Imen; Azzouz, Hichem; Tounsi, Slim

    2013-02-01

    Bacillus thuringiensis subsp. aizawai strain HD133, known by its effectiveness against Spodoptera species, produces many insecticidal proteins including Cry1Ab, Cry1Ca and Cry1Da. In the present study, the insecticidal activity of Cry1Da against Spodoptera littoralis was investigated. It showed toxicity with an LC(50) of 224.4 ng/cm(2) with 95% confidence limits of (178.61-270.19) and an LC(90) of 467.77 ng/cm(2) with 95% confidence limits of (392.89-542.65). The midgut histopathology of Cry1Da fed larvae showed vesicle formation in the apical region, vacuolization and destruction of epithelial cells. Biotinylated-activated Cry1Da toxin bound protein of about 65 kDa on blots of S. littoralis brush border membrane preparations. This putative receptor differs in molecular size from those recognized by Cry1C and Vip3A which are active against this polyphagous insect. This difference in midgut receptors strongly supports the use of Cry1Da as insecticidal agent, particularly in case of Cry and/or Vip-resistance management.

  9. Identification and characterization of a fatty acyl reductase from a Spodoptera littoralis female gland involved in pheromone biosynthesis.

    PubMed

    Carot-Sans, G; Muñoz, L; Piulachs, M D; Guerrero, A; Rosell, G

    2015-02-01

    Fatty acyl-CoA reductases (FARs), the enzymes that catalyse reduction of a fatty acyl-CoA to the corresponding alcohol in insect pheromone biosynthesis, are postulated to play an important role in determining the proportion of each component in the pheromone blend. For the first time, we have isolated and characterized from the Egyptian cotton leaf worm Spodoptera littoralis (Lepidoptera: Noctuidae) a FAR cDNA (Slit-FAR1), which appeared to be expressed only in the pheromone gland and was undetectable in other female tissues, such as fat body, ovaries, wings, legs or thorax. The encoded protein has been successfully expressed in a recombinant system, and the recombinant enzyme is able to produce the intermediate fatty acid alcohols of the pheromone biosynthesis of S. littoralis from the corresponding acyl-CoA precursors. The kinetic variables Km and Vmax, which have been calculated for each acyl-CoA pheromone precursor, suggest that in S. littoralis pheromone biosynthesis other biosynthetic enzymes (e.g. desaturases, acetyl transferase) should also contribute to the final ratio of components of the pheromone blend. In a phylogenetic analysis, Slit-FAR1 appeared grouped in a cluster of other FARs involved in the pheromone biosynthesis of other insects, with little or non-specificity for the natural pheromone precursors.

  10. Diurnal rhythm in expression and release of yolk protein in the testis of Spodoptera littoralis (Lepidoptera: Noctuidae).

    PubMed

    Kotwica, Joanna; Joachimiak, Ewa; Polanska, Marta A; Majewska, Magdalena M; Giebultowicz, Jadwiga M; Bebas, Piotr

    2011-04-01

    Circadian clocks (oscillators) regulate multiple life functions in insects. The circadian system located in the male reproductive tract of Lepidoptera is one of the best characterized peripheral oscillators in insects. Our previous research on the cotton leafworm, Spodoptera littoralis, demonstrated that this oscillator controls the rhythm of sperm release from the testis and coordinates sperm maturation in the upper vas deferens (UVD). We demonstrated previously that a protein that functions as yolk protein in females is also produced in cyst cells surrounding sperm bundles in the testis, and is released into the UVD. Here, we investigated the temporal expression of the yolk protein 2 (yp2) gene at the mRNA and protein level in the testis of S. littoralis, and inquired whether their expression is regulated by PER-based molecular oscillator. We describe a circadian rhythm of YP2 accumulation in the UVD seminal fluid, where this protein interacts with sperm in a circadian fashion. However, we also demonstrate that yp2 mRNA and YP2 protein levels within cyst cells show only a diurnal rhythm in light/dark (LD) cycles. These rhythms do not persist in constant darkness (DD), suggesting that they are non-circadian. Interestingly, the per gene mRNA and protein levels in cyst cells are rhythmic in LD but not in DD. Nevertheless, per appears to be involved in the diurnal timing of YP2 protein accumulation in cyst cells.

  11. Expression and modulation of neuroligin and neurexin in the olfactory organ of the cotton leaf worm Spodoptera littoralis.

    PubMed

    Durand, Nicolas; Chertemps, Thomas; Bozzolan, Françoise; Maïbèche, Martine

    2017-04-01

    Carboxylesterases are enzymes widely distributed within living organisms. In insects, they have been mainly involved in dietary metabolism and detoxification function. Interestingly, several members of this family called carboxylesterase-like adhesion molecules (CLAMs) have lost their catalytic properties and are mainly involved in neuro/developmental functions. CLAMs include gliotactins, neurotactins, glutactins, and neuroligins. The latter have for binding partner the neurexin. In insects, the function of these proteins has been mainly studied in Drosophila central nervous system or neuromuscular junction. Some studies suggested a role of neuroligins and neurexin in sensory processing but CLAM expression within sensory systems has not been investigated. Here, we reported the identification of 5 putative CLAMs expressed in the olfactory system of the model pest insect Spodoptera littoralis. One neuroligin, Slnlg4-yll and its putative binding partner neurexin SlnrxI were the most expressed in the antennae and were surprisingly associated with olfactory sensilla. In addition, both transcripts were upregulated in male antennae after mating, known to modulate the sensitivity of the peripheral olfactory system in S. littoralis, suggesting that these molecules could be involved in sensory plasticity.

  12. Study of the Bacillus thuringiensis Vip3Aa16 histopathological effects and determination of its putative binding proteins in the midgut of Spodoptera littoralis.

    PubMed

    Abdelkefi-Mesrati, Lobna; Boukedi, Hanen; Dammak-Karray, Mariam; Sellami-Boudawara, Tahya; Jaoua, Samir; Tounsi, Slim

    2011-02-01

    The bacterium Bacillus thuringiensis produces, at the vegetative stage of its growth, Vip3A proteins with activity against a broad spectrum of lepidopteran insects. The Egyptian cotton leaf worm (Spodoptera littoralis) is an important agricultural pest that is susceptible to the Vip3Aa16 protein of Bacillus thuringiensis kurstaki strain BUPM95. The midgut histopathology of Vip3Aa fed larvae showed vacuolization of the cytoplasm, brush border membrane destruction, vesicle formation in the apical region and cellular disintegration. Biotinylated Vip3Aa toxin bound proteins of 55- and 100-kDa on blots of S. littoralis brush border membrane preparations. These binding proteins differ in molecular size from those recognized by Cry1C, one of the very few Cry proteins active against the polyphagous S. littoralis. This result supports the use of Vip3Aa16 proteins as insecticidal agent, especially in case of Cry-resistance management.

  13. Selection and characterisation of an HD1-like Bacillus thuringiensis isolate with a high insecticidal activity against Spodoptera littoralis (Lepidoptera: Noctuidae).

    PubMed

    Azzouz, Hichem; Kebaili-Ghribi, Jihene; ben Farhat-Touzri, Dalel; Daoud, Fatma; Fakhfakh, Ines; Tounsi, Slim; Jaoua, Samir

    2014-08-01

    Spodoptera littoralis (Boisduval) larvae are known by their susceptibility to Bacillus thuringiensis subsp. aizawai strains. In order to prevent the appearance of B. thuringiensis (Bt) resistance and to develop economical Bt-based biopesticides, the selection and the characterisation of a B. thuringiensis isolate toxic against S. littoralis larvae and overproducing δ-endotoxins were investigated. Among 124 Tunisian B. thuringiensis isolates assessed against S. littoralis larvae, four isolates showed toxicity similar to and higher than the toxicity of the aizawai strain HD133 and the kurstaki strain HD1 respectively. The plasmid pattern of the selected isolates was similar to that of HD1. Polymerase chain reaction (PCR) analysis using specific primers revealed that these isolates present different gene contents. The only detected gene encoding Spodoptera-specific toxin was cry9. The selected isolates were found to produce bipyramidal and cubic crystals. The assessment of δ-endotoxin production by these isolates showed that BUPM28 produced 43.71 and 80.81% more δ-endotoxin than HD1 and HD133 respectively. The application of osmotic or heat shock stress on the BUPM28 isolate made it possible to enhance δ-endotoxin production by 22 and 23% respectively. On the basis of its potent insecticidal activity and its high level of δ-endotoxin production, the BUPM28 isolate can be considered to be an effective alternative for the control of S. littoralis. © 2013 Society of Chemical Industry.

  14. A porin-like protein from oral secretions of Spodoptera littoralis larvae induces defense-related early events in plant leaves.

    PubMed

    Guo, Huijuan; Wielsch, Natalie; Hafke, Jens B; Svatoš, Aleš; Mithöfer, Axel; Boland, Wilhelm

    2013-09-01

    Insect herbivory on plants is a complex incident consisting of at least two different aspects, namely mechanical damage and chemical challenge, as feeding insects introduce oral secretions (OS) into the wounded tissue of the attacked plant. Mechanical wounding alone is sufficient to induce a set of defense-related reactions in host plants, but some early events such as membrane potential (Vm) changes and cytosolic Ca²⁺-elevations can be triggered only by herbivores suggesting that OS-derived molecules are involved in those processes. Following an assay-guided purification based on planar lipid bilayer membrane technique in combination with proteomic analysis, a porin-like protein (PLP) of most likely bacterial origin was determined from collected OS of Spodoptera littoralis larvae. PLP exhibited channel-forming activity. Further, early defense-related events in plant-insect interaction were evaluated by using a purified fraction and α-hemolysin (α-HL) as a commercial pore-forming compound. Both up-regulated the calmodulin-like CML42 in Arabidopsis thaliana, which only responds to oral secretion and not to wounding. An elevation of in vivo [Ca²⁺](cyt) was not observed. Because membrane channel formation is a widespread phenomenon in plant-insect interactions, this PLP might represent an example for microbial compounds from the insect gut which are initially involved in plant-insect interactions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Deep-tissue confocal imaging of the central projections of ovipositor sensory afferents in the Egyptian cotton leafworm, Spodoptera littoralis.

    PubMed

    Seada, Mervat A; Ghaninia, Majid

    2016-03-01

    The pre-ovipositon behavior of moths is largely dependent upon the cues that a gravid female perceives while assessing potential oviposition sites. Assessment of such sites is accomplished, at least in part, by mechanosensory and gustatory sensilla located on the ovipositor whose sensory neurons project into the terminal abdominal ganglion (TAG). Using anterograde backfill staining, confocal laser scanning microscopy, and three dimensional reconstruction, we traced and analyzed the central projections of the sensory neurons housed in the sensilla located on the ovipositor papillae and explored the neuropilar composition of the TAG in the Egyptian cotton leafworm, Spodoptera littoralis. The TAG consists of three fused neuromeres (6-8th Ner) associated with the 6-8th abdominal segments. Within the TAG, and specifically in the 8th neuromere, four unstructured neuropilar compartments are present; the dorso-ipsilateral motor neuropil (MN), the medio-ipsilateral mechanosensory neuropil (MchN), the medio-ipsilateral small gustatory neuropil (GN), and the medio-contralateral posterior ovipositor glomerulus (Og). The Og appears quite compact, with a hollow core free of terminal arborizations. The MchN is further subdivided into 4 unstructured glomeruli in the 8th neuromere, whose afferents are subsequently extended into 3 glomeruli in the 7th and 6th neuromeres. Few neurites of the Og are populated with large dense varicosities reminiscent of neurosecretory vesicles. Given that all ovipositor nerves converge into a common ganglionic center, the TAG, we assume that this ganglion may be a center for coordination of oviposition behaviors, including movements of the ovipositor during assessment of oviposition substrates and egg laying in S. littoralis.

  16. Cytochrome P450s and cytochrome P450 reductase in the olfactory organ of the cotton leafworm Spodoptera littoralis.

    PubMed

    Pottier, M-A; Bozzolan, F; Chertemps, T; Jacquin-Joly, E; Lalouette, L; Siaussat, D; Maïbèche-Coisne, M

    2012-12-01

    Cytochrome P450 enzymes (P450s) are involved in many physiological functions in insects, such as the metabolism of signal molecules, adaptation to host plants and insecticide resistance. Several P450s have been reported in the olfactory organs of insects, the antennae, and have been proposed to play a role in odorant processing and/or xenobiotic metabolism. Despite recent transcriptomic analyses in several species, the diversity of antennal P450s in insects has not yet been investigated. Here, we report the identification of 37 putative P450s expressed in the antennae of the pest moth Spodoptera littoralis, as well as the characterization of a redox partner, cytochrome P450 reductase (CPR). Phylogenetic analysis revealed that S. littoralis P450s belong to four clades defined by their conservation with vertebrate P450s and their cellular localization. Interestingly, the CYP3 and CYP4 clans, which have been described to be mainly involved in the metabolism of plant compounds and xenobiotics, were largely predominant. More surprisingly, two P450s related to ecdysteroid metabolism were also identified. Expression patterns in adult and larval tissues were studied. Eight P450s appeared to be specific to the chemosensory organs, ie the antennae and proboscis, suggesting a specific role in odorant and tastant processing. Moreover, exposure of males to a plant odorant down-regulated the transcript level of CPR, revealing for the first time the regulation of this gene by odorants within insect antennae. This work suggests that the antennae of insects are a key site for P450-mediated metabolism of a large range of exogenous and endogenous molecules. © 2012 Royal Entomological Society.

  17. Modulation of reproductive behaviors by non-host volatiles in the polyphagous Egyptian cotton leafworm, Spodoptera littoralis.

    PubMed

    Binyameen, Muhammad; Hussain, Altaf; Yousefi, Fatemeh; Birgersson, Göran; Schlyter, Fredrik

    2013-10-01

    In order to locate mates, food, and oviposition sites, insects mainly rely on volatile cues released by their sexual partners, food sources, and host and non-host plants. Calling, mating, and oviposition behaviors, as well as fecundity and longevity, of newly emerged Spodoptera littoralis (Bois.) moths were recorded in the presence of volatiles from leaves of a host plant, Gossypium hirsutum (cotton) and two non-host plants, Adhatoda vasica (Av) or Picea abies (spruce), either alone or in host/non-host combinations. Females exposed to cotton volatiles started calling earlier than females exposed to non-host plant volatiles (NHV), or the blank control. Likewise, moth pairs exposed to cotton volatiles started mating earlier than the other treatments. The period of calling in females alone was longer than females kept with males, having the opportunity to mate. However, the callings, as well as mating durations in the moth pairs, in different treatments were not different. Longevity was decreased either in the absence of cotton or the presence of Av, and spruce leaves. Fecundity was reduced in moths exposed to a combination of spruce and cotton. The effect of NHV on attraction of 2-3-day-old male moths towards a pheromone (Ph) source was studied in a wind tunnel. In the no-choice assay, more males arrived at close approach and landed on the Ph source when the host plant, cotton, was offered in the background as compared to the non-hosts. In the dual-choice assay, more males landed on the Ph source in front of the host plant compared to the Ph source in front of non-hosts. Gas chromatography-electroantennographic detection on female S. littoralis revealed five antennally active compounds in headspace collections of spruce and three compounds in Av.

  18. Functional characterization of a sex pheromone receptor in the pest moth Spodoptera littoralis by heterologous expression in Drosophila.

    PubMed

    Montagné, Nicolas; Chertemps, Thomas; Brigaud, Isabelle; François, Adrien; François, Marie-Christine; de Fouchier, Arthur; Lucas, Philippe; Larsson, Mattias C; Jacquin-Joly, Emmanuelle

    2012-09-01

    Moth sex pheromone communication is recognised as a long-standing model for insect olfaction studies, and a widespread knowledge has been accumulated on this subject thanks to numerous chemical, electrophysiological and behavioural studies. A key step has been the identification of candidate sex pheromone receptors, opening new routes to understanding the specificity and sensitivity of this communication system, but only few of these receptors have as yet been functionally characterised. In this context, we aim at unravelling the molecular bases of pheromone reception in the noctuid moth Spodoptera littoralis. Taking advantage of a collection of antennal-expressed sequence tags, we previously identified three fragments of candidate pheromone receptors in this species. Here, we report full-length cloning of one of these receptors, named SlitOR6. Both sequence and expression pattern analyses were consistent with its annotation as a pheromone receptor, which we further confirmed by functional characterization. Using Drosophila antennae as a heterologous expression system, we identified a single component of the pheromone blend of S. littoralis, (Z,E)-9,12-tetradecadienyl acetate, as the ligand of SlitOR6. Two strategies were employed: (i) expressing SlitOR6 in the majority of Drosophila olfactory neurons, in addition to endogenous receptors, and monitoring the responses to pheromone stimuli by electroantennography; (ii) replacing the Drosophila pheromone receptor OR67d with SlitOR6 and monitoring the response by single sensillum recordings. Results were fully congruent and responses to (Z,E)-9,12-tetradecadienyl acetate were highly specific in both heterologous systems. This approach appears to be efficient and reliable for studying moth pheromone receptors in an in vivo context.

  19. Genome-wide In Silico Analysis, Characterization and Identification of Microsatellites in Spodoptera littoralis Multiple nucleopolyhedrovirus (SpliMNPV)

    PubMed Central

    Atia, Mohamed A. M.; Osman, Gamal H.; Elmenofy, Wael H.

    2016-01-01

    In this study, we undertook a survey to analyze the distribution and frequency of microsatellites or Simple Sequence Repeats (SSRs) in Spodoptera littoralis multiple nucleopolyhedrovirus (SpliMNPV) genome (isolate AN–1956). Out of the 55 microsatellite motifs, identified in the SpliMNPV-AN1956 genome using in silico analysis (inclusive of mono-, di-, tri- and hexa-nucleotide repeats), 39 were found to be distributed within coding regions (cSSRs), whereas 16 were observed to lie within intergenic or noncoding regions. Among the 39 motifs located in coding regions, 21 were located in annotated functional genes whilst 18 were identified in unknown functional genes (hypothetical proteins). Among the identified motifs, trinucleotide (80%) repeats were found to be the most abundant followed by dinucleotide (13%), mononucleotide (5%) and hexanucleotide (2%) repeats. The 39 motifs located within coding regions were further validated in vitro by using PCR analysis, while the 21 motifs located within known functional genes (15 genes) were characterized using nucleotide sequencing. A comparison of the sequence analysis data of the 21 sequenced cSSRs with the published sequences is presented. Finally, the developed SSR markers of the 39 motifs were further mapped/localized onto the SpliMNPV-AN1956 genome. In conclusion, the SSR markers specific to SpliMNPV, developed in this study, could be a useful tool for the identification of isolates and analysis of genetic diversity and viral evolutionary status. PMID:27650818

  20. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis.

    PubMed

    Osman, Gamal H; Assem, Shireen K; Alreedy, Rasha M; El-Ghareeb, Doaa K; Basry, Mahmoud A; Rastogi, Anshu; Kalaji, Hazem M

    2015-12-14

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica.

  1. Biodiversity and Activity of the Gut Microbiota across the Life History of the Insect Herbivore Spodoptera littoralis

    PubMed Central

    Chen, Bosheng; Teh, Beng-Soon; Sun, Chao; Hu, Sirui; Lu, Xingmeng; Boland, Wilhelm; Shao, Yongqi

    2016-01-01

    Microbes that live inside insects play critical roles in host nutrition, physiology, and behavior. Although Lepidoptera (butterflies and moths) are one of the most diverse insect taxa, their microbial symbionts are little-studied, particularly during metamorphosis. Here, using ribosomal tag pyrosequencing of DNA and RNA, we investigated biodiversity and activity of gut microbiotas across the holometabolous life cycle of Spodoptera littoralis, a notorious agricultural pest worldwide. Proteobacteria and Firmicutes dominate but undergo a structural “metamorphosis” in tandem with its host. Enterococcus, Pantoea and Citrobacter were abundant and active in early-instar, while Clostridia increased in late-instar. Interestingly, only enterococci persisted through metamorphosis. Female adults harbored high proportions of Enterococcus, Klebsiella and Pantoea, whereas males largely shifted to Klebsiella. Comparative functional analysis with PICRUSt indicated that early-instar larval microbiome was more enriched for genes involved in cell motility and carbohydrate metabolism, whereas in late-instar amino acid, cofactor and vitamin metabolism increased. Genes involved in energy and nucleotide metabolism were abundant in pupae. Female adult microbiome was enriched for genes relevant to energy metabolism, while an increase in the replication and repair pathway was observed in male. Understanding the metabolic activity of these herbivore-associated microbial symbionts may assist the development of novel pest-management strategies. PMID:27389097

  2. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis

    PubMed Central

    Osman, Gamal H.; Assem, Shireen K.; Alreedy, Rasha M.; El-Ghareeb, Doaa K.; Basry, Mahmoud A.; Rastogi, Anshu; Kalaji, Hazem M.

    2015-01-01

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica. PMID:26658494

  3. Calcium activates a chloride conductance likely involved in olfactory receptor neuron repolarization in the moth Spodoptera littoralis.

    PubMed

    Pézier, Adeline; Grauso, Marta; Acquistapace, Adrien; Monsempes, Christelle; Rospars, Jean-Pierre; Lucas, Philippe

    2010-05-05

    The response of insect olfactory receptor neurons (ORNs) to odorants involves the opening of Ca(2+)-permeable channels, generating an increase in intracellular Ca(2+) concentration. Here, we studied the downstream effect of this Ca(2+) rise in cultured ORNs of the moth Spodoptera littoralis. Intracellular dialysis of Ca(2+) from the patch pipette in whole-cell patch-clamp configuration activated a conductance with a K(1/2) of 2.8 microm. Intracellular and extracellular anionic and cationic substitutions demonstrated that Cl(-) carries this current. The anion permeability sequence I(-) > NO(3)(-) > Br(-) > Cl(-) > CH(3)SO(3)(-) > gluconate(-) of the Ca(2+)-activated Cl(-) channel suggests a weak electrical field pore of the channel. The Ca(2+)-activated current partly inactivated over time and did not depend on protein kinase C (PKC) and CaMKII activity or on calmodulin. Application of Cl(-) channel blockers, flufenamic acid, 5-nitro-2-(3-phenylpropylamino) benzoic acid, or niflumic acid reversibly blocked the Ca(2+)-activated current. In addition, lowering Cl(-) concentration in the sensillar lymph bathing the ORN outer dendrites caused a significant delay in pheromone response termination in vivo. The present work identifies a new Cl(-) conductance activated by Ca(2+) in insect ORNs presumably required for ORN repolarization.

  4. Study on ecdysteroid levels and gene expression of enzymes related to ecdysteroid biosynthesis in the larval testis of Spodoptera littoralis.

    PubMed

    Iga, Masatoshi; Blais, Catherine; Smagghe, Guy

    2013-01-01

    We investigated here the ecdysteroid titers and the expression of six genes coding for known enzymes of the ecdysteroid biosynthesis in the testes of last instar larvae of the pest cotton leafworm, Spodoptera littoralis. We showed that the timing of the ecdysteroid profile was the same in testes and in hemolymph, with a small peak at day 2 and a large one at day 4 after ecdysis. Ecdysone and 20-hydroxyecdysone (20E) were detected in both tissues. 20E was the major ecdysteroid in testes and in hemolymph from day 4. Interestingly, the gene expression of the steroidogenetic enzymes, Neverland, and the five cytochrome P450 enzymes encoded by the Halloween genes was confirmed in the testes, and varied during the instar. However, from the data obtained so far, we cannot conclude that the measured ecdysteroids in the testes result from the activity of the genes under study. Indeed, it is suggested that the ecdysone produced centrally in the prothoracic glands, could have been transformed into 20E in the testes, where Sl-shade is well expressed. © 2012 Wiley Periodicals, Inc.

  5. Synergistic activity of a Bacillus thuringiensis delta-endotoxin and a bacterial endochitinase against Spodoptera littoralis larvae.

    PubMed Central

    Regev, A; Keller, M; Strizhov, N; Sneh, B; Prudovsky, E; Chet, I; Ginzberg, I; Koncz-Kalman, Z; Koncz, C; Schell, J; Zilberstein, A

    1996-01-01

    In an attempt to increase the insecticidal effect of the delta-endotoxin crystal protein CryIC on the relatively Cry-insensitive larvae of Spodoptera littoralis, a combination of CryIC and endochitinase was used. CryIC comprising the first 756 amino acids from Bacillus thuringiensis K26-21 and endochitinase ChiAII encoded by Serratia marcescens were separately produced in Escherichia coli carrying the genes in overexpression vectors. The endochitinase on its own, even at very low concentrations (0.1 microgram/ml), perforated the larval midgut peritrophic membrane. When applied together with low concentrations of CryIC, a synergistic toxic effect was obtained. In the absence of chitinase, about 20 micrograms of CryIC per ml was required to obtain maximal reduction in larval weight, while only 3.0 micrograms of CryIC per ml caused a similar toxic effect in the presence of endochitinase. Thus, a combination of the Cry protein and an endochitinase could result in effective insect control in transgenic systems in which the Cry protein is not expressed in a crystalline form. PMID:8837413

  6. Possible fatty acyl pheromone precursors in Spodoptera littoralis. Search for 11- and 12-hydroxytetradecanoic acids in the pheromone gland.

    PubMed

    Navarro, I; Fabriàs, G; Camps, F

    1997-04-01

    Lipid extracts of Spodoptera littoralis pheromone glands submitted to acid methanolysis using: (i) sulfuric acid/methanol/benzene (0.1:4:2, by vol) at 90 degrees C for 1 h; (ii) 12 N HCI/methanol (1:2, vol/vol) at 90 degrees C for 1 h, or (iii) 14% BF3-MeOH at 90 degrees C for 1 h did not reveal the presence of either 11- or 12-hydroxytetradecanoic acid in the extracts, as concluded from the gas chromatography-mass spectrometry analyses. Under the above methanolysis conditions, a synthetic sample of methyl (14, 14, 14-2H3) 12-hydroxytetradecanoate remained unaltered. These results may indicate that formation of (E)-11-tetradecenoic acid from tetradecanoic acid does not occur in the pheromone gland by dehydration of an intermediate hydroxyacid. Acid methanolysis of a lipidic extract using BF3-MeOH led to the formation of a mixture of methoxy fatty acid methyl esters, identified by gas chromatography-mass spectrometry. These methoxy derivatives should arise from BF3-catalyzed addition of methanol to the double bond of the natural monounsaturated fatty acyl derivatives present in the gland. Thus, under the same conditions, a synthetic sample of methyl (Z)-11-tetradecenoate was partially transformed into methyl 11-methoxytetradecanoate and methyl 12-methoxytetradecanoate. This reaction might be a useful alternative procedure to obtain methoxy derivatives of olefins, which are very helpful for the structural characterization of the parent alkenes.

  7. Degradation of pheromone and plant volatile components by a same odorant-degrading enzyme in the cotton leafworm, Spodoptera littoralis.

    PubMed

    Durand, Nicolas; Carot-Sans, Gerard; Bozzolan, Françoise; Rosell, Gloria; Siaussat, David; Debernard, Stéphane; Chertemps, Thomas; Maïbèche-Coisne, Martine

    2011-01-01

    Odorant-Degrading Enzymes (ODEs) are supposed to be involved in the signal inactivation step within the olfactory sensilla of insects by quickly removing odorant molecules from the vicinity of the olfactory receptors. Only three ODEs have been both identified at the molecular level and functionally characterized: two were specialized in the degradation of pheromone compounds and the last one was shown to degrade a plant odorant. Previous work has shown that the antennae of the cotton leafworm Spodoptera littoralis, a worldwide pest of agricultural crops, express numerous candidate ODEs. We focused on an esterase overexpressed in males antennae, namely SlCXE7. We studied its expression patterns and tested its catalytic properties towards three odorants, i.e. the two female sex pheromone components and a green leaf volatile emitted by host plants. SlCXE7 expression was concomitant during development with male responsiveness to odorants and during adult scotophase with the period of male most active sexual behaviour. Furthermore, SlCXE7 transcription could be induced by male exposure to the main pheromone component, suggesting a role of Pheromone-Degrading Enzyme. Interestingly, recombinant SlCXE7 was able to efficiently hydrolyze the pheromone compounds but also the plant volatile, with a higher affinity for the pheromone than for the plant compound. In male antennae, SlCXE7 expression was associated with both long and short sensilla, tuned to sex pheromones or plant odours, respectively. Our results thus suggested that a same ODE could have a dual function depending of it sensillar localisation. Within the pheromone-sensitive sensilla, SlCXE7 may play a role in pheromone signal termination and in reduction of odorant background noise, whereas it could be involved in plant odorant inactivation within the short sensilla. © 2011 Durand et al.

  8. Evidence for negative cross resistance to insecticides in field collected Spodoptera littoralis (Boisd.) from Lebanon in laboratory bioassays.

    PubMed

    Miles, M; Lysandrou, M

    2002-01-01

    A sample of Spodoptera littoralis pupae were field collected from in Lebanon in November 1999. Approximately 50 healthy pupae were used to initiate a laboratory colony (stain code LEB). As a benchmark for sensitivity to insecticides the susceptible laboratory strain (LET) was used for comparison. The LET stain has been held in laboratory culture for over 10 years and originated from Israel. Three test chemicals were investigated; Spinosad (Tracer, 480 g/L SC), chlorpyrifos (Dursban 480 g/L EC) and cypermethrin (Ambush C 100 g/L EC) representing a range of different modes of actions. To estimate the sensitivity of the LEB strain relative to the LET stain laboratory bioassays, conducted on second instar larvae exposed treated tomato leaves for two days. The method used was based on IRAC (Insecticide Resistance Action Committee) insecticide susceptibly test number 7. Larvae from the LEB strain were tested in both the F1 and F2 laboratory generations. LC50 values were calculated using a Log-Probit model allowing the susceptibly of each strain to each test item to be compared. The LEB (field) strain were approximately twice as sensitive to spinosad compared with the LET (laboratory) strain. The LEB strain was 6-10 times less sensitive to chlorpyrifos which was within the range expected. However the LEB stain was 250-360 times less sensitive to cypermethrin compared with the LET strain, indicating a high level of resistance to pyrethroids in the field population. This kind of relationship gave a strong indication for negative cross resistance between spinosad and cypermethrin. It was concluded that spinosad had potential as a resistance management tool due to its novel mode of action and negative cross resistance with pyrethroids.

  9. A Comparison of the Olfactory Gene Repertoires of Adults and Larvae in the Noctuid Moth Spodoptera littoralis

    PubMed Central

    Poivet, Erwan; Gallot, Aurore; Montagné, Nicolas; Glaser, Nicolas; Legeai, Fabrice; Jacquin-Joly, Emmanuelle

    2013-01-01

    To better understand the olfactory mechanisms in a lepidopteran pest model species, the cotton leafworm Spodoptera littoralis, we have recently established a partial transcriptome from adult antennae. Here, we completed this transcriptome using next generation sequencing technologies, namely 454 and Illumina, on both adult antennae and larval tissues, including caterpillar antennae and maxillary palps. All sequences were assembled in 77,643 contigs. Their analysis greatly enriched the repertoire of chemosensory genes in this species, with a total of 57 candidate odorant-binding and chemosensory proteins, 47 olfactory receptors, 6 gustatory receptors and 17 ionotropic receptors. Using RT-PCR, we conducted the first exhaustive comparison of olfactory gene expression between larvae and adults in a lepidopteran species. All the 127 candidate olfactory genes were profiled for expression in male and female adult antennae and in caterpillar antennae and maxillary palps. We found that caterpillars expressed a smaller set of olfactory genes than adults, with a large overlap between these two developmental stages. Two binding proteins appeared to be larvae-specific and two others were adult-specific. Interestingly, comparison between caterpillar antennae and maxillary palps revealed numerous organ-specific transcripts, suggesting the complementary involvement of these two organs in larval chemosensory detection. Adult males and females shared the same set of olfactory transcripts, except two male-specific candidate pheromone receptors, two male-specific and two female-specific odorant-binding proteins. This study identified transcripts that may be important for sex-specific or developmental stage-specific chemosensory behaviors. PMID:23565215

  10. Degradation of Pheromone and Plant Volatile Components by a Same Odorant-Degrading Enzyme in the Cotton Leafworm, Spodoptera littoralis

    PubMed Central

    Durand, Nicolas; Carot-Sans, Gerard; Bozzolan, Françoise; Rosell, Gloria; Siaussat, David; Debernard, Stéphane; Chertemps, Thomas; Maïbèche-Coisne, Martine

    2011-01-01

    Background Odorant-Degrading Enzymes (ODEs) are supposed to be involved in the signal inactivation step within the olfactory sensilla of insects by quickly removing odorant molecules from the vicinity of the olfactory receptors. Only three ODEs have been both identified at the molecular level and functionally characterized: two were specialized in the degradation of pheromone compounds and the last one was shown to degrade a plant odorant. Methodology Previous work has shown that the antennae of the cotton leafworm Spodoptera littoralis, a worldwide pest of agricultural crops, express numerous candidate ODEs. We focused on an esterase overexpressed in males antennae, namely SlCXE7. We studied its expression patterns and tested its catalytic properties towards three odorants, i.e. the two female sex pheromone components and a green leaf volatile emitted by host plants. Conclusion SlCXE7 expression was concomitant during development with male responsiveness to odorants and during adult scotophase with the period of male most active sexual behaviour. Furthermore, SlCXE7 transcription could be induced by male exposure to the main pheromone component, suggesting a role of Pheromone-Degrading Enzyme. Interestingly, recombinant SlCXE7 was able to efficiently hydrolyze the pheromone compounds but also the plant volatile, with a higher affinity for the pheromone than for the plant compound. In male antennae, SlCXE7 expression was associated with both long and short sensilla, tuned to sex pheromones or plant odours, respectively. Our results thus suggested that a same ODE could have a dual function depending of it sensillar localisation. Within the pheromone-sensitive sensilla, SlCXE7 may play a role in pheromone signal termination and in reduction of odorant background noise, whereas it could be involved in plant odorant inactivation within the short sensilla. PMID:22216190

  11. Biopotency of serine protease inhibitors from cowpea (Vigna unguiculata) seeds on digestive proteases and the development of Spodoptera littoralis (Boisduval).

    PubMed

    Abd El-latif, Ashraf Oukasha

    2015-05-01

    Serine protease inhibitors (PIs) have been described in many plant species and are universal throughout the plant kingdom, where trypsin inhibitors is the most common type. In the present study, trypsin and chymotrypsin inhibitory activity was detected in the seed flour extracts of 13 selected cultivars/accessions of cowpea. Two cowpea cultivars, Cream7 and Buff, were found to have higher trypsin and chymotrypsin inhibitory potential compared to other tested cultivars for which they have been selected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Cream7-purified proteins showed two bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) corresponding to molecular mass of 17.10 and 14.90 kDa, while the purified protein from Buff cultivar showed a single band corresponding mass of 16.50 kDa. The purified inhibitors were stable at temperature below 60°C and were active at wide range of pH from 2 to 12. The kinetic analysis revealed noncompetitive type of inhibition for both inhibitors against both enzymes. The inhibitor constant (Ki ) values suggested high affinity between inhibitors and enzymes. Purified inhibitors were found to have deep and negative effects on the mean larval weight, larval mortality, pupation, and mean pupal weight of Spodoptera littoralis, where Buff PI was more effective than Cream7 PI. It may be concluded that cowpea PI gene(s) could be potential insect control protein for future studies in developing insect-resistant transgenic plants. © 2014 Wiley Periodicals, Inc.

  12. Efficacy of some plant oils alone and/or combined with different insecticides on the cotton leaf-worm Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) in Egypt.

    PubMed

    Mesbah, H A; Mourad, A K; Rokaia, A Z M

    2006-01-01

    The present work was conducted to evaluate the efficiency of two essential oils ((Flax or "Linseed" and Sesame ), five volatile plant oils ( Camphor, Red basil, Rose, Menthol and Clove ), four pesticides (Methoxyfenozide; Permethrin; Profenofos and Spinosad) and their mixtures on the cotton leaf-worm Spodoptera littoralis (Boisd.). This study was also devoted to minimize the usage of conventional insecticides, reduce the environmental pollution, and protect human-beings and domestic animals from hazards due to pesticides applications. In the meantime, the delayed effect of these tested plant oils on the developing immatures and moths of the cotton leaf-worm, Spodoptera littoralis was determined. Most of the evaluated plant oils were found to have an insecticidal effect on the 4th instar larvae of the cotton leaf-worm, S. littoralis. Both the essential Sesame oil and Clove volatile oil showed rather weak toxic effect corresponding to the same concentrations and periods of the bioassay tests. Comparing the toxicity of the tested plant oils, it was affirmed that both Rose and Red basil volatile oils were the highest efficient natural phytocompounds against the treated larvae and alternatively ranked either the 1st and/or the 2nd rank, throughout the different periods of the bioassay tests, followed by the other three tested oils which were more or less efficient phytocompounds. According to the toxicity index, all the tested oils were less toxic than the superior Red basil volatile oil after 48 h. post treatment followed by the gradual decrease in toxicity of Rose, Flax and Menthol, respectively. The development of the treated 4th larval instar was blocked due to treatment with the tested plant oils. With no exception, all the efficiently tested essential and/or volatile oils acted principally as Insect Growth Inhibitors (IGIs) rather than antifeedants causing disruption of the insect development, abnormal larvae, pupae and adults that were lead finally to death. The

  13. Toxical effect of Peganum harmala L. leaves on the cotton leaf worm, Spodoptera littoralis Boisd and its parasitoids Microplitis rufiventris Kok.

    PubMed

    Shonouda, Mourad; Osman, Salah; Salama, Osama; Ayoub, Amal

    2008-02-15

    The leaf extract and its fractions of Peganum harmala L. have shown pronounced mortal effect, decreased percent pupation and adult emergence of the cotton leaf worm, Spodoptera littoralis Boisd. The third instar larvae fed for two days on treated leaves were more susceptible to plant extract and its ethyl acetate and chloroform fractions. The active lowest concentration (5%) of the leaf fractions of P. harmala showed significant effect on the percentage of emerged adult parasitoids, Microplitis rufiventris Kok. GC/MS analysis showed the major constituent in ethyl acetate fraction was (23S) ethylcholest-5-en-3 beta-ol (28.04%) while those of chloroform fraction were hydroxyfuranocoumarin (Bergaptol) (15.68%), piperidinone (12.08%), thymol (11.82%), phosphoric acid, tributyl ester (9.80%) and trimethyl-nonenol (9.66%). The medicinal plant P. harmala could be carefully applied in integrated pest management due to its strong effect on cotton leaf worm pest.

  14. Very high-density lipoprotein and vitellin as carriers of novel biliverdins IXα with a farnesyl side-chain presumably derived from heme A in Spodoptera littoralis.

    PubMed

    Kayser, Hartmut; Nimtz, Manfred; Ringler, Philippe; Müller, Shirley A

    2016-01-01

    Bilins in complex with specific proteins play key roles in many forms of life. Biliproteins have also been isolated from insects; however, structural details are rare and possible functions largely unknown. Recently, we identified a high-molecular weight biliprotein from a moth, Cerura vinula, as an arylphorin-type hexameric storage protein linked to a novel farnesyl biliverdin IXα; its unusual structure suggests formation by cleavage of mitochondrial heme A. In the present study of another moth, Spodoptera littoralis, we isolated two different biliproteins. These proteins were identified as a very high-density lipoprotein (VHDL) and as vitellin, respectively, by mass spectrometric sequencing. Both proteins are associated with three different farnesyl biliverdins IXα: the one bilin isolated from C. vinula and two new structurally closely related bilins, supposed to be intermediates of heme A degradation. The different bilin composition of the two biliproteins suggests that the presumed oxidations at the farnesyl side-chain take place mainly during egg development. The egg bilins are supposedly transferred from hemolymph VHDL to vitellin in the female. Both biliproteins show strong induced circular dichroism activity compatible with a predominance of the M-conformation of the bilins. This conformation is opposite to that of the arylphorin-type biliprotein from C. vinula. Electron microscopy of the VHDL-type biliprotein from S. littoralis provided a preliminary view of its structure as a homodimer and confirmed the biochemically determined molecular mass of ∼350 kDa. Further, images of S. littoralis hexamerins revealed a 2 × 3 construction identical to that known from the hexamerin from C. vinula.

  15. Reduced expression of the immediate-early protein IE0 enables efficient replication of Autographa californica multiple nucleopolyhedrovirus in poorly permissive Spodoptera littoralis cells.

    PubMed

    Lu, Liqun; Du, Quansheng; Chejanovsky, Nor

    2003-01-01

    Infection of Spodoptera littoralis SL2 cells with the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) results in apoptosis and low yields of viral progeny, in contrast to infection with S. littoralis nucleopolyhedrovirus (SlNPV). By cotransfecting SL2 cells with AcMNPV genomic DNA and a cosmid library representing the complete SlNPV genome, we were able to rescue AcMNPV replication and to isolate recombinant virus vAcSL2, which replicated efficiently in SL2 cells. Moreover, vAcSL2 showed enhanced infectivity for S. littoralis larvae compared to AcMNPV. The genome of vAcSL2 carried a 519-bp insert fragment that increased the distance between the TATA element and the transcriptional initiation site (CAGT) of immediate-early gene ie0. This finding correlated with low steady-state levels of IE0 and higher steady-state levels of IE1 (the product of the ie1 gene, a major AcMNPV transactivator, and a multifunctional protein) than of IE0. Mutagenesis of the ie0 promoter locus by insertion of the chloramphenical acetyltransferase (cat) gene yielded a new recombinant AcMNPV with replication properties identical to those of vAcSL2. Thus, the analysis indicated that increasing the steady-state levels of IE1 relative to IE0 should enable AcMNPV replication in SL2 cells. This suggestion was confirmed by constructing a recombinant AcMNPV bearing an extra copy of the ie1 gene under the control of the Drosophila hsp70 promoter. These results suggest that IE0 plays a role in the regulation of AcMNPV infection and show, for the first time, that significant improvement in the ability of AcMNPV to replicate in a poorly permissive cell line and organism can be achieved by increasing the expression of the main multiple functional protein, IE1.

  16. Colonization of the Intestinal Tract of the Polyphagous Pest Spodoptera littoralis with the GFP-Tagged Indigenous Gut Bacterium Enterococcus mundtii

    PubMed Central

    Teh, Beng-Soon; Apel, Johanna; Shao, Yongqi; Boland, Wilhelm

    2016-01-01

    The alkaline gut of Lepidopterans plays a crucial role in shaping communities of bacteria. Enterococcus mundtii has emerged as one of the predominant gut microorganisms in the gastrointestinal tract of the major agricultural pest, Spodoptera littoralis. Therefore, it was selected as a model bacterium to study its adaptation to harsh alkaline gut conditions in its host insect throughout different stages of development (larvae, pupae, adults, and eggs). To date, the mechanism of bacterial survival in insects' intestinal tract has been unknown. Therefore, we have engineered a GFP-tagged species of bacteria, E. mundtii, to track how it colonizes the intestine of S. littoralis. Three promoters of different strengths were used to control the expression of GFP in E. mundtii. The promoter ermB was the most effective, exhibiting the highest GFP fluorescence intensity, and hence was chosen as our main construct. Our data show that the engineered fluorescent bacteria survived and proliferated in the intestinal tract of the insect at all life stages for up to the second generation following ingestion. PMID:27379058

  17. Behavioral and metabolic effects of sublethal doses of two insecticides, chlorpyrifos and methomyl, in the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae).

    PubMed

    Dewer, Youssef; Pottier, Marie-Anne; Lalouette, Lisa; Maria, Annick; Dacher, Matthieu; Belzunces, Luc P; Kairo, Guillaume; Renault, David; Maibeche, Martine; Siaussat, David

    2016-02-01

    Insecticides have long been used as the main method in limiting agricultural pests, but their widespread use has resulted in environmental pollution, development of resistances, and biodiversity reduction. The effects of insecticides at low residual doses on both the targeted crop pest species and beneficial insects have become a major concern. In particular, these low doses can induce unexpected positive (hormetic) effects on pest insects, such as surges in population growth exceeding what would have been observed without pesticide application. Methomyl and chlorpyrifos are two insecticides commonly used to control the population levels of the cotton leafworm Spodoptera littoralis, a major pest moth. The aim of the present study was to examine the effects of sublethal doses of these two pesticides, known to present a residual activity and persistence in the environment, on the moth physiology. Using a metabolomic approach, we showed that sublethal doses of methomyl and chlorpyrifos have a systemic effect on the treated insects. We also demonstrated a behavioral disruption of S. littoralis larvae exposed to sublethal doses of methomyl, whereas no effects were observed for the same doses of chlorpyrifos. Interestingly, we highlighted that sublethal doses of both pesticides did not induce a change in acetylcholinesterase activity in head of exposed larvae.

  18. EPR spectroscopic characterization of the iron-sulphur proteins and cytochrome P-450 in mitochondria from the insect Spodoptera littoralis (cotton leafworm).

    PubMed Central

    Shergill, J K; Cammack, R; Chen, J H; Fisher, M J; Madden, S; Rees, H H

    1995-01-01

    EPR spectroscopy was used to investigate the cytochrome P-450-dependent steroid hydroxylase ecdysone 20-mono-oxygenase of the cotton leafworm (Spodoptera littoralis) and the redox centres associated with membranes from the fat-body mitochondrial fraction. Intense features at g = 2.42, 2.25 and 1.92 from oxidized mitochondrial membranes have been assigned to the low-spin haem form of ferricytochrome P-450, probably of ecdysone 20-mono-oxygenase. High-spin cytochrome P-450 (substrate-bound) was tentatively assigned to a signal at g = 8.0, which was detectable from membranes as prepared. An EPR signal characteristic of a [2Fe-2S] cluster detected from the soluble mitochondrial matrix fraction has been shown to be distinct from the signals associated with mitochondrial NADH dehydrogenase and succinate dehydrogenase, and has therefore been attributed to a ferredoxin. We conclude that the S. littoralis fat-body mitochondrial electron-transport system involved in steroid 20-hydroxylation comprises both ferredoxin and cytochrome P-450 components, and thus resembles the enzyme systems of adrenocortical mitochondria. EPR signals characteristic of the respiratory chain were also observed from fat-body mitochondria and assigned to the iron-sulphur clusters associated with Complex I (Centres N1, N2), Complex II (Centres S1, S3), Complex III (the Rieske centre), and the copper centre of Complex IV, demonstrating similarities to mammalian mitochondria. The reduced membrane fraction also yielded a major resonance at g = 2.09 and 1.88 characteristic of the [4Fe-4S] cluster of electron-transferring flavoprotein: ubiquinone oxidoreductase. As the fat-body is the major metabolic organ of insects, this protein is presumably required for the beta-oxidation of fatty acids in mitochondria. High-spin haem signals in the low-field region of spectra also demonstrated that the mitochondrial fraction contains relatively high concentrations of catalase. PMID:7741702

  19. A promising HD133-like strain of Bacillus thuringiensis with dual efficiency to the two Lepidopteran pests: Spodoptera littoralis (Noctuidae) and Ephestia kuehniella (Pyralidae).

    PubMed

    BenFarhat-Touzri, Dalel; Driss, Fatma; Tounsi, Slim

    2016-08-01

    Isolation and identification of new strains with wide variety of target pests is an ever growing field. In this paper, a screening of 260 strains from Tunisian soil samples was conducted by dot-blot and PCR-sequencing analysis. The screening was done on the basis of the possession of cry1D-type genes and was followed by the evaluation of the insecticidal activity against Spodoptera littoralis. BLB250 strain showed an LC50 value (56.2 μg g(-1)) against S. littoralis lower than those of the two Bacillus thuringiensis reference strains HD1 and HD133. An interesting LC50 (167.6 μg g(-1)) was also recorded against Ephestia kuehniella larvae. The strain was, thus, selected because of its qualification to be highly toxic, at once, for both Lepidopteran insects. In vitro time course of proteolytic processing of BLB250 and HD133 protoxins by the gut juices from the two insect larvae revealed that the differences in toxicity against E. kuehniella are most likely attributed to differences in the efficiency of the activation of the corresponding protoxins into toxins. An activation comparative study using commercial proteases suggested that the intestinal proteases of E. kuehniella contain trypsin-like activities. With its high efficiency and toxicity against, at once, two Lepidopteran insects having different susceptibilities towards kurstaki and aizawai subspecies, BLB250 could be useful when developing more efficient and economical B. thuringiensis-based pesticides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Interaction of the Koinobiont Parasitoid Microplitis rufiventris of the Cotton Leafworm, Spodoptera littoralis, with Two Entomopathogenic Rhabditids, Heterorhabditis bacteriophora and Steinernema carpocapsae

    PubMed Central

    Atwa, Atwa A.; Hegazi, Esmat M.; Khafagi, Wedad E.; El-Aziz, Gehan M. Abd

    2013-01-01

    Entomopathogenic nematodes are generally considered beneficial organisms. However, they can affect beneficial insects such as parasitoids. The interaction between the entomopathogenic nematodes Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae) and Steinernema carpocapsae Weiser, and the parasitoid Microplitis rufiventris Kokujev (Hymenoptera: Braconidae) was investigated in the laboratory. In non-parasitized hosts, Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae) larvae exposed to H. bacteriophora showed a higher percent mortality than those exposed to S. carpocapsae. Both nematodes were able to invade and propagate in non-parasitized S. littoralis larvae and those parasitized by M. rufiventris. Both nematode species reproduced in Microplitis-parasitized hosts, but there was a higher number of nematodes in non-parasitized larvae. S. carpocapsae yielded higher numbers of infective juveniles than H. bacteriophora. Generally, the number of nematodes harvested increased as their host's size increased. The interaction between the nematodes and parasitoid favored the nematodes when the nematodes were inoculated during the parasitoid egg stage or the young parasitoid larvae, thus giving the nematodes a better chance to grow and reproduce, resulting in the death of the parasitoid larvae. Conversely, when the nematodes were inoculated during the late larval instar of the parasitoid, the competition partially favored the wasp, thus giving approximately 50% of the wasps a better chance to develop, emerge, and reproduce, providing evidence that both nematodes and wasps could reproduce in the same host. Egg maturation of female wasps derived from nematode-infected hosts was not significantly different than those from control hosts. The combined application of nematodes and parasitoids may be beneficial if the detrimental effects of the nematodes on the parasitoid could be avoided by precisely timing the application strategies. It is clear that

  1. Insecticidal Effect of Chrysanthemum coronarium L. Flowers on the Pest Spodoptera littoralis Boisd and its Parasitoid Microplitis rufiventris Kok. with Identifying the Chemical Composition

    NASA Astrophysics Data System (ADS)

    Shonouda, Mourad L.; Osman, Salah; Salama, Osama; Ayoub, Amal

    The flower extract of Chrysanthemum coronarium L. and their fractions have shown insecticidal effect on the cotton leaf worm Spodoptera littoralis. The third instar larvae fed for two days on treated leaves were more susceptible to plant extracts and to their ethyl acetate and chloroform fractions. The active lowest concentration (5%) of the flower fractions showed no significant effect on the percent reduction of emerged adult parasitoids, Microplitis rufiventris Kok. GC/MS analysis revealed that the major constituents in ethyl acetate fraction were 3-dihydro-methylene-2- (3H) furanone (17.8%), jasmolin I (15.6%), carveol 1 (13.6%), phosphoric acid, tributyl ester (11.4%) and cinerin II (11.1%), while those of chloroform fraction were 5-hydroxy-3 methyl-1H-pyrazole (42.7%) and carveol 1(24.8%). The medicinal plant C. coronarium seems to be a promising plant for application in integrated pest management due to its safety to the surrounding environment.

  2. Clock-controlled rhythm of ecdysteroid levels in the haemolymph and testes, and its relation to sperm release in the Egyptian cotton leafworm, Spodoptera littoralis.

    PubMed

    Polanska, Marta A; Maksimiuk-Ramirez, Ewa; Ciuk, Marcin A; Kotwica, Joanna; Bebas, Piotr

    2009-05-01

    In Spodoptera littoralis, testicular sperm release occurs in a daily rhythm, which is controlled by endogenous circadian oscillator located in the male reproductive system. Although this rhythm is essential for male fertility, factors that initiate and maintain daily sperm release are not understood. In this study, we investigated a modulatory role for ecdysteroids in the sperm release rhythm and identified the source of ecdysteroids in adult males. We found that the onset of sperm release occurs two days pre-eclosion and coincides with a significant decrease in haemolymph ecdysteroids levels. 20-HE injection into the pupae prior to the first sperm release delayed its initiation and disrupted the developing rhythm in a dose dependent manner. 20-HE injection into adults depressed the number of sperm bundles leaving the testes. A day before the initial sperm release, ecdysteroid levels in the haemolymph and testes begin to oscillate in a circadian fashion. Ecdysteroid rhythms continue throughout imaginal life and correlate with the rhythm of sperm release. In each cycle, testicular sperm release coincides with a trough in testicular ecdysteroid concentration. Rhythmic changes in ecdysteroid levels are regulated by an endogenous circadian oscillator that continues to function in decapitated males. The generation of a complete cycle of ecdysteroid release by testes cultured in vitro indicates that this oscillator is located in the gonads. The haemolymph ecdysteroid levels are significantly lower and arrhythmic in males with removed testes, indicating that the testes are an important ecdysteroid source that may contribute to oscillations in haemolymph ecdysteroid levels.

  3. Nicotiana attenuata MPK4 suppresses a novel jasmonic acid (JA) signaling-independent defense pathway against the specialist insect Manduca sexta, but is not required for the resistance to the generalist Spodoptera littoralis.

    PubMed

    Hettenhausen, Christian; Baldwin, Ian T; Wu, Jianqiang

    2013-08-01

    How plants tailor their defense responses to attack from different insects remains largely unknown. Here, we studied the role of a mitogen-activated protein kinase (MAPK), MPK4, in the resistance of a wild tobacco Nicotiana attenuata to two herbivores, the specialist Manduca sexta and the generalist Spodoptera littoralis. Stably transformed N. attenuata plants silenced in MPK4 (irMPK4) were generated and characterized for traits important for defense against herbivores. Only the oral secretions (OS) from M. sexta, but not the OS from S. littoralis or mechanical wounding, induced elevated levels of jasmonic acid (JA) in irMPK4 plants relative to the wild-type plants. Moreover, silencing of MPK4 strongly increased the resistance of N. attenuata to M. sexta in a fashion that was independent of COI1 (CORONATINE INSENSITIVE1)-mediated JA signaling. Untargeted metabolomic screening identified several new MPK4-dependent putative defensive compounds against M. sexta. By contrast, silencing of MPK4 did not affect the growth of the generalist insect S. littoralis, and we propose that this was because of the very low levels of fatty acid-amino acid conjugates (FACs) in S. littoralis OS. Thus, MPK4 is likely to be a key signaling element that enables plants to tailor defense responses to different attackers. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  4. High-performance liquid chromatography-diode array detection-electrospray ionization multi-stage mass spectrometric screening of an insect/plant system: the case of Spodoptera littoralis/Lycopersicon esculentum phenolics and alkaloids.

    PubMed

    Ferreres, Federico; Taveira, Marcos; Gil-Izquierdo, Angel; Oliveira, Luísa; Teixeira, Tânia; Valentão, Patrícia; Simões, Nelson; Andrade, Paula B

    2011-07-30

    High-performance liquid chromatography-diode array detection-electrospray ionization multi-stage mass spectrometry (HPLC-DAD-ESI-MS(n)) is considered to be a very valuable tool for the characterization of compounds found in trace amounts in natural matrices, as their previous isolation and clean-up steps can be avoided. Micro-scale separation increases the potential of this analytical technique, allowing the determination of compounds in reduced samples. Spodoptera littoralis represents a major challenge to Solanaceae plants, as it is one of the most deleterious pests. The S. littoralis/Lycopersicon esculentum system was studied for the first time concerning glycoalkaloids and phenolics. Using HPLC-DAD-ESI-MS(n) we were able to characterize 15 phenolic compounds in L. esculentum leaves. Nine of them are reported for the first time. Some differences were found between leaves of cerasiforme and 'Bull's heart' varieties. However, in the materials of S. littoralis (larvae, adults, exuviae and excrements) reared in both L. esculentum leaves no phenolics were identified. α-Tomatine was the main glycoalkaloid in the host plant. The glycoalkaloid composition of the different S. littoralis materials was distinct, with α-tomatine and dehydrotomatine being the main detected compounds in larvae and excrements. These results add knowledge to the ecological interaction in this insect/plant duo, for which it is hard to obtain considerable sample amounts. Copyright © 2011 John Wiley & Sons, Ltd.

  5. Purification and characterisation of haemolymph 3-dehydroecdysone 3 beta-reductase in relation to ecdysteroid biosynthesis in the cotton leafworm Spodoptera littoralis.

    PubMed

    Chen, J H; Webb, T J; Powls, R; Rees, H H

    1996-12-01

    The in vitro secretion of ecdysteroids from the prothoracic glands of last instar larvae of Spodoptera littoralis was detected and analysed by HPLC-RIA. The primary product was identified as 3-dehydroecdysone (approximately 82%), with lesser amounts of ecdysone (approximately 18%). Interconversion of ecdysone and 3-dehydroecdysone by prothoracic glands was not detectable. 3-Dehydroecdysone 3 beta-reductase activity was demonstrated in the haemolymph. Ecdysone, the endproduct, was characterised by reverse-phase and adsorption HPLC, chemical transformation into ecdysone 2, 3-acetonide, and mass spectrometry. The conditions for optimal activity were determined. The enzyme requires NADPH or NADH as cofactor and Km values for NADPH and NADH were determined to be 0.94 microM, and 22.8 microM, respectively. Investigation of the kinetic properties of the enzyme, using either NADPH or NADH as cofactor, revealed that it exhibits maximal activity at low 3-dehydroecdysone substrate concentrations, with a drastic inhibition of activity at higher concentrations (> 5 microM). The results suggest that the 3-dehydroecdysone 3 beta-reductase has a high-affinity (low Km) binding site for 3-dehydroecdysone substrate, together with a lower-affinity inhibition site. The 3 beta-reductase enzyme was purified to homogeneity using a combination of poly(ethylene glycol) 6000 precipitation and successive FPLC fractionation on Mono-Q, phenyl Superose (twice), and hydroxyapatite columns. The native enzyme was shown to be a monomer with molecular mass of 36 kDa by SDS/PAGE and gel-filtration chromatography. Furthermore, the activity of the enzyme during the last larval instar was found to reach a peak prior to that of the haemolymph ecdysteroid titre, supporting a role for the enzyme in development.

  6. Bestrophin-Encoded Ca2+-Activated Cl− Channels Underlie a Current with Properties Similar to the Native Current in the Moth Spodoptera littoralis Olfactory Receptor Neurons

    PubMed Central

    Demondion, Elodie; Bozzolan, Françoise; Debernard, Stéphane; Lucas, Philippe

    2012-01-01

    Responses of insect olfactory receptor neurons (ORNs) involve an entry of Ca2+ through olfactory heterodimeric receptor complexes. In moths, the termination of ORN responses was found to strongly depend on the external Ca2+ concentration through the activation of unknown Ca2+-dependent Cl− channels. We thus investigated the molecular identity of these Cl− channels. There is compelling evidence that bestrophins form Cl− channels when expressed in heterologous systems. Here we provide evidence that antennae of the moth Spodoptera littoralis express three transcripts encoding proteins with hallmarks of bestrophins. One of these transcripts, SlitBest1b, is expressed in ORNs. The heterologous expression of SlitBest1b protein in CHO-K1 cells yielded a Ca2+-activated Cl− current that shares electrophysiological properties with the native Ca2+-activated Cl− current of ORNs. Both currents are anionic, present similar dependence on the intracellular Ca2+ concentration, partly inactivate over time, have the same anion permeability sequence, the same sequence of inhibitory efficiency of blockers, the same almost linear I–V relationships and finally both currents do not depend on the cell volume. Therefore, our data suggest that SlitBest1b is a good candidate for being a molecular component of the olfactory Ca2+-activated Cl− channel and is likely to constitute part of the insect olfactory transduction pathway. A different function (e.g. regulation of other proteins, maintenance of the anionic homeostasis in the sensillar lymph) and a different role (e.g. involvement in the olfactory system development) cannot be excluded however. PMID:23300744

  7. Carbonic anhydrase activity in the vas deferens of the cotton leafworm - Spodoptera littoralis (Lepidoptera: Noctuidae) controlled by circadian clock.

    PubMed

    Kotwica, J; Ciuk, M A; Joachimiak, E; Rowinski, S; Cymborowski, B; Bebas, P

    2006-11-01

    The male reproductive tract of Lepidoptera is an ideal model for the study of the physiological role of peripheral clocks in insects. The latter are significant in the generation and coordination of rhythmic phenomena which facilitate the initial stages of sperm capacitation. This process requires the maintenance of pH in the upper vas deferens (UVD) aided by, among others, H+-ATPase. Our aim was to determine the potential involvement of carbonic anhydrase (CA) in this process, an enzyme tasked with generating protons subsequently utilized by H+-ATPase to acidify the UVD milieu in S. littoralis, during the time when the lumen of this organ is filled with sperm. We attempted to answer the question whether CA activity can be controlled by the biological oscillator present in the male reproductive tract of the cotton leafworm. Using PAGE zymography, the presence of CA was demonstrated in the UVD wall, but not in the luminal fluid nor in the sperm. Using histochemistry, it was shown that CA is active in the UVD epithelium, and that this activity varies throughout the day and is most likely controlled by an endogenous biological clock. Conversely, the application of CA inhibitors, acetazolamide and sodium thiocyanate, in conjunction with an analysis of H+-ATPase activity in the acidification the UVD environment shows that CA most likely does not play a direct role in the regulation of the pH in this organ.

  8. Direct Contact - Sorptive Tape Extraction coupled with Gas Chromatography - Mass Spectrometry to reveal volatile topographical dynamics of lima bean (Phaseolus lunatus L.) upon herbivory by Spodoptera littoralis Boisd.

    PubMed

    Boggia, Lorenzo; Sgorbini, Barbara; Bertea, Cinzia M; Cagliero, Cecilia; Bicchi, Carlo; Maffei, Massimo E; Rubiolo, Patrizia

    2015-04-12

    The dynamics of plant volatile (PV) emission, and the relationship between damaged area and biosynthesis of bioactive molecules in plant-insect interactions, remain open questions. Direct Contact-Sorptive Tape Extraction (DC-STE) is a sorption sampling technique employing non adhesive polydimethylsiloxane tapes, which are placed in direct contact with a biologically-active surface. DC-STE coupled to Gas Chromatography - Mass Spectrometry (GC-MS) is a non-destructive, high concentration-capacity sampling technique able to detect and allow identification of PVs involved in plant responses to biotic and abiotic stresses. Here we investigated the leaf topographical dynamics of herbivory-induced PV (HIPV) produced by Phaseolus lunatus L. (lima bean) in response to herbivory by larvae of the Mediterranean climbing cutworm (Spodoptera littoralis Boisd.) and mechanical wounding by DC-STE-GC-MS. Time-course experiments on herbivory wounding caused by larvae (HW), mechanical damage by a pattern wheel (MD), and MD combined with the larvae oral secretions (OS) showed that green leaf volatiles (GLVs) [(E)-2-hexenal, (Z)-3-hexen-1-ol, 1-octen-3-ol, (Z)-3-hexenyl acetate, (Z)-3-hexenyl butyrate] were associated with both MD and HW, whereas monoterpenoids [(E)-β-ocimene], sesquiterpenoids [(E)-nerolidol] and homoterpenes (DMNT and TMTT) were specifically associated with HW. Up-regulation of genes coding for HIPV-related enzymes (Farnesyl Pyrophosphate Synthase, Lipoxygenase, Ocimene Synthase and Terpene Synthase 2) was consistent with HIPV results. GLVs and sesquiterpenoids were produced locally and found to influence their own gene expression in distant tissues, whereas (E)-β-ocimene, TMTT, and DMNT gene expression was limited to wounded areas. DC-STE-GC-MS was found to be a reliable method for the topographical evaluation of plant responses to biotic and abiotic stresses, by revealing the differential distribution of different classes of HIPVs. The main advantages of this

  9. Joint action of quercetin with four insecticides on the cotton leaf-worm larvae, Spodoptera littoralis Boisd. (Lep. : Noctuidae) in Egypt.

    PubMed

    Mesbah, H A; Saad, A S A; Mourad, A K; Taman, F A; Mohamed, I B

    2007-01-01

    The naturally occurring phytoncidal chemical component of some plant- species are responsible for controlling and/or repelling insects from host plants. The use of natural products, readily available in the environment, to control the cotton leafworm, could be of help in reducing the need for applying the synthetic conventional insecticides . Moreover, crude vegetable oils application is quite safer to the non targets and the environment. The use of sex attractant pheromones as predicative tools to forecast pest population and their potential damage levels in specific crops, has significantly been limited because sex attractants are usually directed to one sex only. Thus, identification of plant constituents that attract S. littoralis Boisd. adults, especially females, and that directly affect their feeding or reproductive behaviour, would greatly expand opportunities for manipulation of the biological and environmental events that prevent the establishment, development, and dispersal of the insect-pest under study. Extracted Volatiles from certain parts of cotton plants, attracted both sexes of the cotton leafworm moths instead of attracting one sex only as the pheromones do. Plant flavonoids have been shown by many investigators to have an effect on insect behaviour, growth, and development. Quercetin is one of many bioflavonoids that exists in several fruits and vegetables. The Aim of the present work is to study in vivo the biochemical mode of action of quercetin as a synergist in combination with insecticides. The present results proved the synergistic effect of quercetin when combined with four insecticides, namely, profenofos (organophosphates), deltamethrin (pyrethroid), and tebufenozide et hexaflumuron as insect growth regulators against the studied insect-pest. Quercetin role as a synergist might be attributed to its ability to inhibit certain active oxidases, which may be responsible for in vivo detoxification of the intact insecticides when applied to

  10. Effects of Ricinus communis, Brassica nigra and mineral oil Kemesol on some biochemical aspects of larvae stage of Spodoptera littoralis (Boisd) (Lepidoptera: Noctuidae).

    PubMed

    Khatter, Najat A; Abuldahb, Faten F

    2010-04-01

    The third instars larvae of Spodotera littoralis were topically treated with two plant oils, Ricinus communis and Brassica nigra and one mineral oil, Kemesol 95% dissolved in petroleum ether and acetone at concentrations of 0.8, 1.6, 2.0, 3.0 & 4 %. The results revealed that the mean values of the total haemolymph and fat body protein was reduced in larvae treated with B. nigra and Kemesol 95%. A significant decrease was observed in haemolymph and fat body protein contents in larvae treated with all tested compound, the remarked decrease was noticed at the highest dose (4%) in both two solvents.

  11. Bestrophin-encoded Ca²⁺-activated Cl⁻ channels underlie a current with properties similar to the native current in the moth Spodoptera littoralis olfactory receptor neurons.

    PubMed

    François, Adrien; Grauso, Marta; Demondion, Elodie; Bozzolan, Françoise; Debernard, Stéphane; Lucas, Philippe

    2012-01-01

    Responses of insect olfactory receptor neurons (ORNs) involve an entry of Ca²⁺ through olfactory heterodimeric receptor complexes. In moths, the termination of ORN responses was found to strongly depend on the external Ca²⁺ concentration through the activation of unknown Ca²⁺-dependent Cl⁻ channels. We thus investigated the molecular identity of these Cl⁻ channels. There is compelling evidence that bestrophins form Cl⁻ channels when expressed in heterologous systems. Here we provide evidence that antennae of the moth Spodoptera littoralis express three transcripts encoding proteins with hallmarks of bestrophins. One of these transcripts, SlitBest1b, is expressed in ORNs. The heterologous expression of SlitBest1b protein in CHO-K1 cells yielded a Ca²⁺-activated Cl⁻ current that shares electrophysiological properties with the native Ca²⁺-activated Cl⁻ current of ORNs. Both currents are anionic, present similar dependence on the intracellular Ca²⁺ concentration, partly inactivate over time, have the same anion permeability sequence, the same sequence of inhibitory efficiency of blockers, the same almost linear I-V relationships and finally both currents do not depend on the cell volume. Therefore, our data suggest that SlitBest1b is a good candidate for being a molecular component of the olfactory Ca²⁺-activated Cl⁻ channel and is likely to constitute part of the insect olfactory transduction pathway. A different function (e.g. regulation of other proteins, maintenance of the anionic homeostasis in the sensillar lymph) and a different role (e.g. involvement in the olfactory system development) cannot be excluded however.

  12. Efficacy of sub lethal concentration of entomopathogenic fungi on the feeding and reproduction of Spodoptera litura.

    PubMed

    Vinayaga Moorthi, P; Balasubramanian, C; Selvarani, S; Radha, A

    2015-01-01

    In the present investigation, impact of sub lethal concentrations of entomopathogenic fungi, namely Isaria fumosorosea, Beauveria bassiana and Paecilomyces variotii, secondary metabolite on feeding, growth, fecundity and hatchability of Spodoptera litura was performed. The S. litura treated with I. fumosorosea and B. bassiana metabolites exhibited renounced food consumption. The growth rate of treated S. litura with metabolite of I. fumosorosea had drastic reduction. In the case of approximate digestibility (AD), maximum impact was established by the I. fumosorosea isolate, which significantly reduced the approximate digestibility of the IV and V instar larvae. The III instar larvae of S. litura treated with I. fumosorosea metabolite showed significantly lower efficiency of conversion of digested food (ECD) and efficiency of conversion of ingested food (ECI) values than IV and V instars. However the performance of metabolites on fecundity and hatchability of S. litura was immense. Therefore, metabolites of I. fumosorosea could be reliable biocontrol agent, which has been highly recommended for S. litura management in commercial crops.

  13. Diet dependent metabolic responses in three generalist insect herbivores Spodoptera spp.

    PubMed

    Roy, A; Walker, W B; Vogel, H; Chattington, S; Larsson, M C; Anderson, P; Heckel, D G; Schlyter, F

    2016-04-01

    Adaption to dietary changes is critical in the evolution of host plant ranges in polyphagous insects. We compared three taxa of lepidopteran herbivores from the predominantly generalist genus Spodoptera showing different degrees of polyphagy: Spodoptera littoralis, with a broad host range including both mono- and dicotyledonous plants, and two Spodoptera frugiperda strains [Corn (i.e. maize) (C) and Rice (R)] adapted primarily to different grass species. When feeding on maize we show a lower performance in the broad generalist taxon compared to the grass adapted taxa. Among these taxa, the maize adapted S. frugiperda C-strain generally performed better than the R-strain on maize leaves. On artificial pinto diet, all taxa performed well. Our RNA-Seq analysis of midgut transcriptomes from 3rd instar larvae feeding on maize showed broader transcriptional readjustments in the generalist S. littoralis compared to grass adapted S. frugiperda strains. Substantial alteration in the expression levels of midgut physiological function related transcripts, such as digestive and detoxifying enzymes, transporters, immunity, and peritrophic membrane associated transcripts, existed in all taxa. We found high background expression of UDP-glucosyl transferases, which are known to neutralize maize leaf toxins, in the maize adapted S. frugiperda C-strain, contributing to its fitness on maize compared to the R-strain. Our findings provide evidence for divergent diet specific response of digestive physiology within these Spodoptera taxa. Unexpectedly, the C- and R-strains of S. frugiperda fed on the same diet showed large differences in expression patterns between these two closely related taxa. Copyright © 2016. Published by Elsevier Ltd.

  14. Spodoptera exigua caterpillar feeding induces rapid defense responses in maize leaves

    USDA-ARS?s Scientific Manuscript database

    Insects such as beet armyworm caterpillars (Spodoptera exigua) cause extensive damage to maize (Zea mays) by consuming foliar tissue. Maize plants respond to insect attack by triggering defense mechanisms that involve massive changes in gene expression, biosynthesis of specialized metabolites and de...

  15. Glutathione S-transferase SlGSTE1 in Spodoptera litura may be associated with feeding adaptation of host plants.

    PubMed

    Zou, Xiaopeng; Xu, Zhibin; Zou, Haiwang; Liu, Jisheng; Chen, Shuna; Feng, Qili; Zheng, Sichun

    2016-03-01

    Spodoptera litura is polyphagous pest insect and feeds on plants of more than 90 families. In this study the role of glutathione S-transferase epilson 1 (slgste1) in S. litura in detoxification was examined. This gene was up-regulated in the midgut of S. litura at the transcriptional and protein levels when the insect fed on Brassica juncea or diet containing phytochemicals such as indole-3-carbinol and allyl-isothiocyanate that are metabolic products of sinigrin and glucobrassicin in B. juncea. The SlGSTE1 could catalyze the conjugation of reduced glutathione and indole-3-carbinol and allyl-isothiocyanate, as well as xanthotoxin, which is a furanocoumarin, under in vitro condition. When the expression of Slgste1 in the larvae was suppressed with RNAi, the larval growth and feeding rate were decreased. Furthermore, the up-regulated expression of the SlGSTE1 protein in the midgut of larvae that fed on different host plants was detected by 2-DE and ESI/MS analysis. The feeding adaptation from the most to the least of the larvae for the various host plants was Brassica alboglabra, Brassica linn. Pekinensis, Cucumis sativus, Ipomoea batatas, Arachis hypogaea and Capsicum frutescens. All the results together suggest that Slgste1 is a critical detoxifying enzyme that is induced by phytochmicals in the host plants and, inter alia, may be related to host plant adaptation of S. litura. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Monitoring for exotic Spodoptera species (Lepidoptera: Noctuidae) in Florida

    USDA-ARS?s Scientific Manuscript database

    Trapping studies were conducted in two Florida locations to determine if three Old World Spodoptera Guenée species were present. Commercially-produced lures for S. exempta (Walker), S. littoralis (Boisduval), and S. litura (F.), plus a S. litura lure made by the USDA-APHIS-CPHST laboratory at Otis ...

  17. A correlation between macronutrient balancing and insect host-plant range: evidence from the specialist caterpillar Spodoptera exempta (Walker).

    PubMed

    Lee, Kwang Pum; Raubenheimer, David; Behmer, Spencer T; Simpson, Stephen J

    2003-12-01

    In an earlier study, we showed that the ingestive responses of the generalist caterpillar Spodoptera littoralis to foods imbalanced in their protein:carbohydrate content is similar to generalist locusts, but differs from that of specialist-feeding locusts. Here we further pursued the comparison by repeating the experiments using a closely related specialist caterpillar, Spodoptera exempta. First, caterpillars were allowed to self-compose a diet of preferred protein:carbohydrate balance by mixing between nutritionally complementary foods. Then, they were confined to one of five imbalanced foods, in which we measured the trade-off between over- and under-ingesting the two nutrients. On complementary foods, the caterpillars actively regulated their protein and carbohydrate intake. In the no-choice experiment, those fed excess-protein foods ingested small surpluses of protein compared with generalist feeders, thus showing a pattern of nutrient balancing similar to that observed in specialist locusts. Utilisation data indicated that ingested excesses and deficits were to some extent offset by differential utilisation. Evidence also showed that post-ingestive responses of the specialist S. exempta were less flexible than those observed in the generalist S. littoralis, a pattern which is again in accordance with comparisons of acridids differing in their host-plant range.

  18. Attraction, Feeding Preference, and Performance of Spodoptera frugiperda Larvae (Lepidoptera: Noctuidae) Reared on Two Varieties of Maize.

    PubMed

    De La Rosa-Cancino, Wilmar; Rojas, Julio C; Cruz-Lopez, Leopolodo; Castillo, Alfredo; Malo, Edi A

    2016-04-01

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an economically important pest of maize and other crops in the Americas. Studies suggest that modern varieties of maize lost some of their natural defense mechanisms against herbivores during domestication and agricultural selection. In the present study, we evaluated the attraction, feeding preference (host fidelity and consumption rate), and performance of S. frugiperda larvae reared on hybrid (Pioneer P4063W) and landrace (Tuxpeño) varieties of maize. We also evaluated the damage caused by S. frugiperda to Pioneer and Tuxpeño maize plants in the field. We found that fifth-instar larvae were more attracted to Pioneer plants than to Tuxpeño plants in a Y-tube olfactometer. Additionally, the fall armyworm larvae showed more fidelity to Pioneer leaves than to Tuxpeño leaves. However, the larval consumption rate was similar for both types of maize plants. The life cycle of S. frugiperda was significantly longer when the larvae were reared on Tuxpeño leaves than on Pioneer leaves. In the field, the Pioneer variety was infested with more S. frugiperda larvae than the Tuxpeño variety. Thus, our results provide evidence that modern varieties of maize may have lost some of their defensive traits during selective breeding.

  19. Feeding-induced phenol production in Capsicum annuum L. influences Spodoptera litura F. larval growth and physiology.

    PubMed

    Movva, Vijaya; Pathipati, Usha Rani

    2017-05-01

    We studied the role of induced plant phenols as a defense response to insect herbivory. Phenolic compounds were induced in Capsicum annuum L., the source of many culinary peppers, after feeding by different stages of the insect pest, Spodoptera litura F. The phenols were identified and quantified using high performance liquid chromatography (HPLC) and effects produced by these phenols on larval development were studied. Vanillic acid was identified in plants challenged by second, fourth, and fifth instar larvae, but not in plants challenged by third instar nor unchallenged plants. Syringic acid production was induced in chili plants infested with second (0.429 ± 0.003 μg/g fresh weight, fourth (0.396 ± 0.01 μg/g fresh weight), and fifth instar (5.5 ± 0.06 μg/g fresh weight) larvae, compared to untreated plants (0.303 ± 0.01 μg/g fresh weight) plants. Leaves surface treated with the rutin deterred oviposition. Dietary exposure to chlorogenic acid, vanillic acid, syringic acid, sinapic acid, and rutin led to enhanced activities of detoxifying enzymes, β-glucosidase, carboxyl esterase, glutathione S-transferase, and glutathione reductase in the midgut tissues of all the larval instars, indicating the toxic nature of these compounds. Protein carbonyl content and acetylcholinesterase activity was analyzed to appreciate the role of induced plant phenols in insect protein oxidation and terminating nerve impulses. © 2017 Wiley Periodicals, Inc.

  20. Effects of Feeding Spodoptera littoralis on Lima Bean Leaves: IV. Diurnal and Nocturnal Damage Differentially Initiate Plant Volatile Emission1[W][OA

    PubMed Central

    Arimura, Gen-ichiro; Köpke, Sabrina; Kunert, Maritta; Volpe, Veronica; David, Anja; Brand, Peter; Dabrowska, Paulina; Maffei, Massimo E.; Boland, Wilhelm

    2008-01-01

    Continuous mechanical damage initiates the rhythmic emission of volatiles in lima bean (Phaseolus lunatus) leaves; the emission resembles that induced by herbivore damage. The effect of diurnal versus nocturnal damage on the initiation of plant defense responses was investigated using MecWorm, a robotic device designed to reproduce tissue damage caused by herbivore attack. Lima bean leaves that were damaged by MecWorm during the photophase emitted maximal levels of β-ocimene and (Z)-3-hexenyl acetate in the late photophase. Leaves damaged during the dark phase responded with the nocturnal emission of (Z)-3-hexenyl acetate, but with only low amounts of β-ocimene; this emission was followed by an emission burst directly after the onset of light. In the presence of 13CO2, this light-dependent synthesis of β-ocimene resulted in incorporation of 75% to 85% of 13C, demonstrating that biosynthesis of β-ocimene is almost exclusively fueled by the photosynthetic fixation of CO2 along the plastidial 2-C-methyl-d-erythritol 4-P pathway. Jasmonic acid (JA) accumulated locally in direct response to the damage and led to immediate up-regulation of the P. lunatus β-ocimene synthase gene (PlOS) independent of the phase, that is, light or dark. Nocturnal damage caused significantly higher concentrations of JA (approximately 2–3 times) along with enhanced expression levels of PlOS. Transgenic Arabidopsis thaliana transformed with PlOS promoter∷β-glucuronidase fusion constructs confirmed expression of the enzyme at the wounded sites. In summary, damage-dependent JA levels directly control the expression level of PlOS, regardless of light or dark conditions, and photosynthesis is the major source for the early precursors of the 2-C-methyl-d-erythritol 4-P pathway. PMID:18165324

  1. Temperature-induced changes in fatty acid dynamics of the intertidal grazer Platychelipus littoralis (Crustacea, Copepoda, Harpacticoida): Insights from a short-term feeding experiment.

    PubMed

    Werbrouck, Eva; Van Gansbeke, Dirk; Vanreusel, Ann; Mensens, Christoph; De Troch, Marleen

    2016-04-01

    Dietary lipids, and in particular the essential fatty acids (EFA), EPA (20:5ω3) and DHA (22:6ω3), guarantee the well-being of animals and are recognized for their potential bottom-up control on animal populations. They are introduced in marine ecosystems through primary producers and when grazed upon, they are consumed, incorporated or modified by first-level consumers. As the availability of EFA in the ecosystem is affected by ambient temperature, the predicted rise in ocean temperature might alter the availability of these EFA at the basis of marine food webs. Despite the FA bioconversion capacity of certain benthic copepod species, their lipid (FA) response to varying temperatures is understudied. Therefore, the temperate, intertidal copepod Platychelipus littoralis was offered a mono and mixed diatom diet at 4, 15 °C (normal range) and at 24 °C (elevated temperature) to investigate the combined effects of temperature and resource availability on its FA content and composition. P. littoralis showed a flexible thermal acclimation response. Cold exposure increased the degree of FA unsaturation and the EPA%, and induced a shift towards shorter chain FA in the copepod's membranes. Furthermore, a mixed diet reduced the impact of heat stress on the copepod's membrane FA composition. Temperature affected the trophic transfer of EPA and DHA differently. While dietary resources could fully compensate for the temperature effects on total lipid and EPA content in the copepods, no such counterweigh was observed for the DHA dynamics. Heat stress lowered the DHA concentration in copepods regardless of the resources available and this implies negative effects for higher trophic levels.

  2. Nitrogen fertilization rate affects feeding, larval performance, and oviposition preference of the beet armyworm, Spodoptera exigua, on cotton

    USDA-ARS?s Scientific Manuscript database

    Nitrogen (N) is one of the most critical chemical elements for plant and animal growth. Development and oviposition of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) was studied in relation to varying nitrogen levels in cotton, Gossypium hirsutum L. The development of S. exig...

  3. [Adult oviposition and larvae feeding behavior of Spodoptera litura (Lepidoptera: Noctuidae) on tobacco plants after infested by B-biotype Bemisia tabaci (Homoptera: Aleyrodidae)].

    PubMed

    Wang, Hong-Tao; Xue, Ming; Chen, Hui-Na; Zhou, Fang-Yuan

    2011-05-01

    To understand the effects of the defense responses of tobacco plants induced by the infesting of B-biotype Bemisia tabaci to Spodoptera litura, and to explore the mechanisms of the interspecific interactions between B-biotype B. tabaci and S. litura, a laboratory experiment was conducted to study the effects of tobacco plants after infested by B-biotype B. tabaci on the adult oviposition selection and the larvae feeding, anti-feeding, and other feeding behaviors of S. litura. Comparing with that on control plants, the egg number oviposited by adult S. litura on the infested plants decreased by 40.9%. The plant leaves infested had great repellent effect to the newly-hatched S. litura larvae, while the middle leaves and the leaves with systemic damage symptom (white-vein) had definite attractive effect. Unexpanded terminal leaves had no effects on the host selection of S. litura larvae. The S. litura larvae had significant anti-feeding behavior on the leaves infested, being more notable than that on the leaves with white-vein. On the leaves infested and with white-vein, the feeding times per unit duration or the feeding percentage of S. litura larvae decreased, the time of initiating feeding prolonged, and the total feeding area declined significantly, compared with the control. In conclusion, the tobacco plants after infested by B-biotype B. tabaci had negative effects on the adult oviposition and larvae feeding of S. litura, and the results of the study would be useful in understanding the population dynamics of tobacco pests and their management.

  4. Use of DNA barcodes to identify invasive armyworm Spodoptera species in Florida.

    PubMed

    Nagoshi, Rodney N; Brambila, Julieta; Meagher, Robert L

    2011-01-01

    A critical component for sustaining adequate food production is the protection of local agriculture from invasive pest insects. Essential to this goal is the ability to accurately distinguish foreign from closely related domestic species, a process that has traditionally required identification using diagnostic morphological "keys" that can be both subtle and labor-intensive. This is the case for the Lepidopteran group of insects represented by Spodoptera, a genus of Noctuidae "armyworm" moths that includes several important agricultural pests. Two of the most destructive species, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) and S. litura (F.) are not yet established in North America. To facilitate the monitoring for these pests, the feasibility of using DNA barcoding methodology for distinguishing between domestic and foreign Spodoptera species was tested. A DNA barcoding database was derived for a subset of Spodoptera species native to Florida, with an emphasis on those attracted to pheromone blends developed for S. litura or S. littoralis. These were then compared to the barcode sequences of S. litura collected from Taiwan and S. littoralis from Portugal. Consistent discrimination of the different species was obtained with phenetic relationships produced that were generally in agreement with phylogenetic studies using morphological characteristics. The data presented here indicate that DNA barcoding has the potential to be an efficient and accurate supplement to morphological methods for the identification of invasive Spodoptera pests in North America.

  5. Use of DNA Barcodes to Identify Invasive Armyworm Spodoptera Species in Florida

    PubMed Central

    Nagoshi, Rodney N.; Brambila, Julieta; Meagher, Robert L.

    2011-01-01

    A critical component for sustaining adequate food production is the protection of local agriculture from invasive pest insects. Essential to this goal is the ability to accurately distinguish foreign from closely related domestic species, a process that has traditionally required identification using diagnostic morphological “keys” that can be both subtle and labor-intensive. This is the case for the Lepidopteran group of insects represented by Spodoptera, a genus of Noctuidae “armyworm” moths that includes several important agricultural pests. Two of the most destructive species, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) and S. litura (F.) are not yet established in North America. To facilitate the monitoring for these pests, the feasibility of using DNA barcoding methodology for distinguishing between domestic and foreign Spodoptera species was tested. A DNA barcoding database was derived for a subset of Spodoptera species native to Florida, with an emphasis on those attracted to pheromone blends developed for S. litura or S. littoralis. These were then compared to the barcode sequences of S. litura collected from Taiwan and S. littoralis from Portugal. Consistent discrimination of the different species was obtained with phenetic relationships produced that were generally in agreement with phylogenetic studies using morphological characteristics. The data presented here indicate that DNA barcoding has the potential to be an efficient and accurate supplement to morphological methods for the identification of invasive Spodoptera pests in North America. PMID:22239735

  6. Sorghum seed maturity affects the weight and feeding duration of immature corn earworm, Helicoverpa zea, and fall armyworm, Spodoptera frugiperda, in the laboratory.

    PubMed

    Soper, Alysha M; Whitworth, R Jeff; McCornack, Brian P

    2013-01-01

    Corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda J.E. Smith, are occasional pests in sorghum, Sorghum bicolor L. Moench (Poales: Poaceae), and can be economically damaging when conditions are favorable. Despite the frequent occurrence of mixed-species infestations, the quantitative data necessary for developing yield loss relationships for S. frugiperda are not available. Although these species share similar biological characteristics, it is unknown whether their damage potentials in developing grain sorghum panicles are the same. Using no-choice feeding assays in the laboratory, this study examined larval growth and feeding duration for H. zea and S. frugiperda in the absence of competition. Each species responded positively when exposed to sorghum seed in the soft-dough stage, supporting evidence for the interactions between host-quality and larval growth and development. The results of this study also confirmed the suitability of using laboratory-reared H. zea to develop sorghum yield loss estimates in the field, and provided insights into the biological responses of S. frugiperda feeding on developing sorghum seed.

  7. Sorghum Seed Maturity Affects the Weight and Feeding Duration of Immature Corn Earworm, Helicoverpa zea, and Fall Armyworm, Spodoptera frugiperda, in the Laboratory

    PubMed Central

    Soper, Alysha M.; Whitworth, R. Jeff; McCornack, Brian P.

    2013-01-01

    Corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda J.E. Smith, are occasional pests in sorghum, Sorghum bicolor L. Moench (Poales: Poaceae), and can be economically damaging when conditions are favorable. Despite the frequent occurrence of mixed-species infestations, the quantitative data necessary for developing yield loss relationships for S. frugiperda are not available. Although these species share similar biological characteristics, it is unknown whether their damage potentials in developing grain sorghum panicles are the same. Using no-choice feeding assays in the laboratory, this study examined larval growth and feeding duration for H. zea and S. frugiperda in the absence of competition. Each species responded positively when exposed to sorghum seed in the soft-dough stage, supporting evidence for the interactions between host-quality and larval growth and development. The results of this study also confirmed the suitability of using laboratory-reared H. zea to develop sorghum yield loss estimates in the field, and provided insights into the biological responses of S. frugiperda feeding on developing sorghum seed. PMID:24219328

  8. Hyperaccumulation of vanadium in the Antarctic polychaete Perkinsiana littoralis as a natural chemical defense against predation.

    PubMed

    Fattorini, Daniele; Notti, Alessandra; Nigro, Marco; Regoli, Francesco

    2010-01-01

    Exceptionally high levels of trace metals have been reported in specific tissues of certain polychaetes. In the present study, the Antarctic fan worm Perkinsiana littoralis was shown to hyperaccumulate vanadium in the branchial tissues, and the hypothesis of an antipredatory strategy has been investigated. Trace metals (Ag, Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, Zn) were measured by atomic absorption spectrophotometry in tissues of P. littoralis and, only for V, in two Antarctic bivalves and in various Mediterranean polychaetes. Subcellular distribution of vanadium was investigated in P. littoralis after differential centrifugations; feeding trials with the Antarctic rock cod Trematomus berancchii were performed to test the palatability of P. littoralis. Analyses of trace metals in tissues of P. littoralis confirmed the naturally high bioavailability of cadmium due to upwelling phenomena in the investigated area and revealed extremely high concentrations of vanadium up to 10,000 microg/g, in the branchial crowns; much lower concentrations were measured in the body portions and even less in the Antarctic bivalves and in Mediterranean polychaetes. The subcellular distribution indicated that this metal was associated in branchial crowns with both heavy components and vanadium binding proteins; the latter predominated in body tissues, although with a different pattern of molecular weight. Feeding trials suggested that the elevated levels of vanadium in branchial crown of P. littoralis act as chemical deterrents against predation in more exposed tissues. The hyperaccumulation of toxic metals might represent a common antipredatory strategy for unpalatable branchial crowns of sabellid polychaetes, as recently hypothesized also for the high concentrations of arsenic in the Mediterranean Sabella spallanzanii. The evolution of such adaptation and the reasons behind the possibility for different species to accumulate different metals represent a stimulating

  9. Metabolism, excretion and avoidance of cyanogenic glucosides in insects with different feeding specialisations.

    PubMed

    Pentzold, Stefan; Zagrobelny, Mika; Bjarnholt, Nanna; Kroymann, Juergen; Vogel, Heiko; Olsen, Carl Erik; Møller, Birger Lindberg; Bak, Søren

    2015-11-01

    Cyanogenic glucosides (CNglcs) are widespread plant defence compounds releasing toxic hydrogen cyanide when hydrolysed by specific β-glucosidases after plant tissue damage. In contrast to specialist herbivores that have mechanisms to avoid toxicity from CNglcs, it is generally assumed that non-adapted herbivores are negatively affected by CNglcs. Recent evidence, however, implies that the defence potential of CNglcs towards herbivores may not be as effective as previously anticipated. Here, performance, metabolism and excretion products of insects not adapted to CNglcs were analysed, including species with different degrees of dietary specialisation (generalists, specialists) and different feeding modes (leaf-snipping lepidopterans, piercing-sucking aphids). Insects were reared either on cyanogenic or acyanogenic plants or on an artificial cyanogenic diet. Lepidopteran generalists (Spodoptera littoralis, Spodoptera exigua, Mamestra brassicae) were compared to lepidopteran glucosinolate-specialists (Pieris rapae, Pieris brassicae, Plutella xylostella), and a generalist aphid (Myzus persicae) was compared to an aphid glucosinolate-specialist (Lipaphis erysimi). All insects were tolerant to cyanogenic plants; in lepidopterans tolerance was mainly due to excretion of intact CNglcs. The two Pieris species furthermore metabolized aromatic CNglcs to amino acid conjugates (Cys, Gly, Ser) and derivatives of these, which is similar to the metabolism of benzylglucosinolates in these species. Aphid species avoided uptake of CNglcs during feeding. Our results imply that non-adapted insects tolerate plant CNglcs either by keeping them intact for excretion, metabolizing them, or avoiding uptake.

  10. Data set for diet specific differential gene expression analysis in three Spodoptera moths.

    PubMed

    Roy, A; Walker, W B; Vogel, H; Kushwaha, S K; Chattington, S; Larsson, M C; Anderson, P; Heckel, D G; Schlyter, F

    2016-09-01

    Examination of closely related species pairs is suggested for evolutionary comparisons of different degrees of polyphagy, which we did here with three taxa of lepidopteran herbivores, Spodoptera spp (S. littoralis, S. frugiperda maize (C) and rice (R) strains) for a RNAseq analysis of the midguts from the 3rd instar insect larvae for differential metabolic responses after feeding on pinto bean based artificial diet vs maize leaves. Paired-end (2×100 bp) Illumina HiSeq2500 sequencing resulted in a total of 24, 23, 24, and 21 million reads for the SF-C-Maize, SF-C-Pinto, SF-R-Maize, SF-R Pinto, and a total of 35 and 36 million reads for the SL-Maize and SL-Pinto samples, respectively. After quality control measures, a total of 62.2 million reads from SL and 71.7 million reads from SF were used for transcriptome assembly (TA). The resulting final de novo reference TA (backbone) for the SF taxa contained 37,985 contigs with a N50 contig size of 1030 bp and a maximum contig length of 17,093 bp, while for SL, 28,329 contigs were generated with a N50 contig size of 1980 bp and a maximum contig length of 18,267 bp. The data presented herein contains supporting information related to our research article Roy et al. (2016) http://dx.doi.org/10.1016/j.ibmb.2016.02.006[1].

  11. Arabidopsis basic helix-loop-helix transcription factors MYC2, MYC3, and MYC4 regulate glucosinolate biosynthesis, insect performance, and feeding behavior.

    PubMed

    Schweizer, Fabian; Fernández-Calvo, Patricia; Zander, Mark; Diez-Diaz, Monica; Fonseca, Sandra; Glauser, Gaétan; Lewsey, Mathew G; Ecker, Joseph R; Solano, Roberto; Reymond, Philippe

    2013-08-01

    Arabidopsis thaliana plants fend off insect attack by constitutive and inducible production of toxic metabolites, such as glucosinolates (GSs). A triple mutant lacking MYC2, MYC3, and MYC4, three basic helix-loop-helix transcription factors that are known to additively control jasmonate-related defense responses, was shown to have a highly reduced expression of GS biosynthesis genes. The myc2 myc3 myc4 (myc234) triple mutant was almost completely devoid of GS and was extremely susceptible to the generalist herbivore Spodoptera littoralis. On the contrary, the specialist Pieris brassicae was unaffected by the presence of GS and preferred to feed on wild-type plants. In addition, lack of GS in myc234 drastically modified S. littoralis feeding behavior. Surprisingly, the expression of MYB factors known to regulate GS biosynthesis genes was not altered in myc234, suggesting that MYC2/MYC3/MYC4 are necessary for direct transcriptional activation of GS biosynthesis genes. To support this, chromatin immunoprecipitation analysis showed that MYC2 binds directly to the promoter of several GS biosynthesis genes in vivo. Furthermore, yeast two-hybrid and pull-down experiments indicated that MYC2/MYC3/MYC4 interact directly with GS-related MYBs. This specific MYC-MYB interaction plays a crucial role in the regulation of defense secondary metabolite production and underlines the importance of GS in shaping plant interactions with adapted and nonadapted herbivores.

  12. 'Do you remember the first time?' Host plant preference in a moth is modulated by experiences during larval feeding and adult mating.

    PubMed

    Proffit, Magali; Khallaf, Mohammed A; Carrasco, David; Larsson, Mattias C; Anderson, Peter

    2015-04-01

    In insects, like in other animals, experience-based modulation of preference, a form of phenotypic plasticity, is common in heterogeneous environments. However, the role of multiple fitness-relevant experiences on insect preference remains largely unexplored. For the multivoltine polyphagous moth Spodoptera littoralis we investigated effects of larval and adult experiences on subsequent reproductive behaviours. We demonstrate, for the first time in male and female insects, that mating experience on a plant modulates plant preference in subsequent reproductive behaviours, whereas exposure to the plant alone or plant together with sex pheromone does not affect this preference. When including larval feeding experiences, we found that both larval rearing and adult mating experiences modulate host plant preference. These findings represent the first evidence that host plant preferences in polyphagous insects are determined by a combination of innate preferences modulated by sensory feedback triggered by multiple rewarding experiences throughout their lifetime.

  13. Effects of drought stressed cotton, Gossypium hirsutum L., on beet armyworm, Spodoptera exigua (Hübner), oviposition, and larval feeding preferences and growth.

    PubMed

    Showler, Allan T; Moran, Patrick J

    2003-09-01

    The beet armyworm, Spodoptera exigua (Hübner), has been anecdotally reported to oviposit more on drought stressed than on nonstressed cotton plants. Using potted cotton plants in cages, this study demonstrated that beet armyworms deposited 3.3, 4.6, and 2.3 times more (P < or = 0.05) eggs on cotton plants that were grown on 1500, 1000, and 750 ml water/wk, respectively, than on cotton plants grown in well watered (4000 ml water/wk) soil. Third instars, however, showed no preference for stressed cotton foliage over nonstressed foliage. Third instar beet armyworms raised on well watered cotton plants were 1.5, 2.3, and 2.6 times heavier than those reared on cotton grown in the 1500, 1000, and 750 ml water/wk plants (P < or = 0.05), respectively. Physiochemical analyses showed that drought stressed leaves had significantly greater accumulations of free amino acids that are essential for insect growth and development. Soluble protein and soluble carbohydrates were also more abundant in stressed leaves compared to nonstressed leaves. Despite the apparent increase in nutritional quality in drought stressed plants, larval survival was reduced, probably because the limiting factor became water. Greater amounts of cotton leaf area were consumed from drought stressed leaves (P < or = 0.05) than from nonstressed leaves, probably because the larvae had to metabolize greater portions of assimilated energy to supplement body water with metabolic water derived from respiration. The association of greater host plant nutritional quality to oviposition preference, and conversely, to reduced survivorship, is discussed.

  14. [Optimization of extraction on flavonoids from leaves of Heritiera littoralis].

    PubMed

    Zhang, Yan-Jun; Peng, Chong-Wei; Xu, Shu-Qing; Zheng, Yun-Ying; Xie, Qing-Juan

    2012-04-01

    To optimize the preparation procedure for extraction of flavonoids from leaves of Heritiera littoralis. Comparing microwave extraction and ultrasonic extraction, The content of total flavonoids was measure by UV spectrophometry and the wavelength set at 510 nm. The effects of treatment time, extraction power, ethanol concentration and solid-liquid ratio were studied. The orthogonal test of four factors and three levels were studied to obtain the extraction technology of flavonoids from leaves of Heritiera littoralis. The optimal technical conditions were mixing leaves of Heritiera littoralis with 70% ethanol on the ratio of 1 g: 30 mL, when microwave treatment time was 8 min and micro-wave power was 400 W. Under this condition, the extraction rate reached 6.15%. This study explores a practical extraction method for flavonoids from leaves of Heritiera littoralis, and lay a good foundation for mangrove medical research in future.

  15. Interactions of Spodoptera littoralis haemocytes following injection with the entomopathogenic fungi: Beauveria bassiana and Nomuraea rileyi.

    PubMed

    Meshrif, Wesam S; Rohlfs, Marko; Hegazi, Mohamed A M; Barakat, Emad M S; Seif, Amal I; Shehata, Magdi G

    2011-12-01

    This study compared the cellular interactions of Spodopteralittoralis haemocytes with two virulence-different entomopathogenic fungi: Beauveriabassiana and Nomuraearileyi. Using light and transmission microscopy, five types of haemocytes namely, prohaemocytes (PRs), plasmatocytes (PLs), granulocytes (GRs), spherule cells (SPs) and oenocytoids (OEs) were identified in the 6th instar larvae. PRs and PLs were found in the haemopoietic tissue. Intra-haemocoelic injection of blastospores induced ultrastructural alterations in the cytoplasm and nuclei of circulating haemocytes of treated larvae. Different responses were observed in the populations of haemocyte types following injection with the tested fungi. The most important changes were the decrease of the numers of GRs accompanied with increase in SPs at 12-48h following injection with B. bassiana, whereas, a decrease of PLs with a commitment increase inSPs and OEs were observed at most time intervals after injection with N. rileyi. Both fungi provoked a decrease of the total number of haemocytes at 48h followed by an increase at 72h post-injection. In vivo assay showed that the GRs and PLs actively phagocytised fungal blastospores. There was a time-dependent decrease and increase in the phagocytosis activity after injection of B. bassiana and N. Rileyi, respectively. In B. bassiana-injected insects, the numbers nodules increased significantly at 6-48h in comparison with the controls post-injection. In N. rileyi-injected insects, nodules increased significantly only at 72h post-injection. No cellular encapsulation was observed in any of the examined insects.

  16. Antiprotozoal and antioxidant alkaloids from Alternanthera littoralis.

    PubMed

    Koolen, Hector H F; Pral, Elizabeth M F; Alfieri, Silvia C; Marinho, Jane V N; Serain, Alessandra F; Hernández-Tasco, Alvaro J; Andreazza, Nathalia L; Salvador, Marcos J

    2017-02-01

    Five alkaloids, in addition to hydroxytyrosol and uridine, were isolated from aerial parts of Alternanthera littoralis P. Beauv. Among the isolated compounds, alternamide A was an unusual tricyclic alkaloid with a bridged benzoazepine core. All isolated alkaloids have a catechol moiety, indicating a possible common biosynthetic route. Their structures were established by 1D and 2D NMR spectroscopy in combination with extensive tandem MS experiments by collisional induced dissociation (CID). The antiprotozoal activity of the isolated compounds was assayed against trypomastigote forms of Trypanosoma cruzi and amastigotes of Leishmania amazonensis. Alternamine A was the most active compound, reducing markedly the viability of both parasites. Antioxidant capacities evaluated by ORACFL assay showed that the isolated alkaloids (mainly alternamide B) contributed to the high activity recorded for the ethanolic crude extract; possibly, the catechol moiety present in all structures plays a central role in this result.

  17. Phytochemical and biological investigation of Hymenocallis littoralis SALISB.

    PubMed

    Abou-Donia, Amina H; Toaima, Soad M; Hammoda, Hala M; Shawky, Eman; Kinoshita, Eri; Takayama, Hiromitsu

    2008-02-01

    A phytochemical investigation of the bulbs and flowers of Hymenocallis littoralis SALISB., cultivated in Egypt, was carried out, which resulted in the isolation of four alkaloids, lycorine (1), hippeastrine (2), 11-hydroxyvittatine (3), and (+)-8-O-demethylmaritidine (4), and of two flavonoids, quercetin 3'-O-glucoside (5), and rutin (6). The volatile constituents of the plant flowers were analyzed for the first time by GC/MS, which led to the identification of 26 known compounds (Table 1). Finally, the antimicrobial activity of the petroleum ether extract of the flowers of H. littoralis was investigated.

  18. RNAi Screening in Spodoptera frugiperda.

    PubMed

    Ghosh, Subhanita; Singh, Gatikrushna; Sachdev, Bindiya; Kumar, Ajit; Malhotra, Pawan; Mukherjee, Sunil K; Bhatnagar, Raj K

    2016-01-01

    RNA interference is a potent and precise reverse genetic approach to carryout large-scale functional genomic studies in a given organism. During the past decade, RNAi has also emerged as an important investigative tool to understand the process of viral pathogenesis. Our laboratory has successfully generated transgenic reporter and RNAi sensor line of Spodoptera frugiperda (Sf21) cells and developed a reversal of silencing assay via siRNA or shRNA guided screening to investigate RNAi factors or viral pathogenic factors with extraordinary fidelity. Here we describe empirical approaches and conceptual understanding to execute successful RNAi screening in Spodoptera frugiperda 21-cell line.

  19. A new chromone from Hymenocallis littoralis Salisb. (Amaryllidaceae).

    PubMed

    Anh, Dinh Thi Phuong; Duong, Tran Bach; Hoang, Vu Dinh

    2014-01-01

    A new chromone, 5,7-dihydroxy-6,8-dimethoxy-2-methyl-4H-chromen-4-one (1), together with seven known compounds, 5,7-dihydroxy-6-methoxy-2-methyl-4H-chromen-4-one (pisonin B) (2), 5,7-dihydroxy-2-methyl-4H-chromen-4-one (noreugenin) (3), 5-hydroxy-7-methoxy-2-methyl-4H-chromen-4-one (eugenin) (4), (2S)-7,4'-dihydroxyflavan (5), 3',7-dihydroxy-4'-methoxy-8-methylflavan (6), 3',7-dihydroxy-4'-methoxyflavan (7) and 6,8-dimethyl-5,7,4'-trihydroxyflavanone (( - )-farrerol) (8), were isolated from Hymenocallis littoralis Salisb. (Amaryllidaceae) growing in Vietnam. Their structures were determined based on spectroscopic and physicochemical analyses.

  20. THE EFFECTS OF LIGHT AND NUTRIENTS ON AN INVASIVE BUDDLEJA DAVIDII AND A NATIVE GRISELINIA LITTORALIS

    EPA Science Inventory

    Buddleja davidii (Family: Buddlejaceae), an aggressive, highly invasive, ornamental

    shrub of Asian origin, may be suppressing slower-growing native species (e.g., Griselinia

    littoralis; Family: Griseliniaceae) on New Zealand floodplains, thus altering successional

  1. THE EFFECTS OF LIGHT AND NUTRIENTS ON AN INVASIVE BUDDLEJA DAVIDII AND A NATIVE GRISELINIA LITTORALIS

    EPA Science Inventory

    Buddleja davidii (Family: Buddlejaceae), an aggressive, highly invasive, ornamental

    shrub of Asian origin, may be suppressing slower-growing native species (e.g., Griselinia

    littoralis; Family: Griseliniaceae) on New Zealand floodplains, thus altering successional

  2. The biology and ecology of Necrodes littoralis, a species of forensic interest in Europe.

    PubMed

    Charabidze, Damien; Vincent, Benoît; Pasquerault, Thierry; Hedouin, Valéry

    2016-01-01

    Necrodes littoralis (Linnaeus, 1758) (Coleoptera: Silphidae), also known as the "shore sexton beetle," is a common silphid beetle that visits and breeds on large vertebrate cadavers. This study describes, for the first time, the involvement of N. littoralis on human corpses based on a large dataset of 154 French forensic cases. Various parameters regarding corpse location, decomposition stages, and entomofauna were extracted from each file. Compared to all of the forensic entomology cases analyzed between 1990 and 2013 (1028), N. littoralis was observed, on average, in one case out of eight; most of these cases occurred during spring and summer (73.5%). More than 90% of the cases were located outdoors, especially in woodlands, bushes, and fields. The decomposition stage of the corpse varied among cases, with more than 50% in the advanced decomposition stage, 36% in the early decomposition stage, and less than 10% in the fresh, mummified, or skeletonized stages. Regarding other necrophagous species sampled with N. littoralis, Calliphorid flies were found in 94% of the cases and Fanniidae/Muscidae in 65% of the cases. Chrysomya albiceps, a heliophilic species mostly located in the Mediterranean area, was present in 34% of the cases (only 20% in the whole dataset). The most common coleopteran species were Necrobia spp. (Coleoptera: Cleridae) and Creophilus maxillosus (Coleoptera: Staphylinidae); these beetles were observed in 27% of the cases. The over-representation of these species is likely due to similar requirements regarding the climate and decomposition stage. As N. littoralis is frequently observed and tends to become more common, we conclude that the developmental data for this species would be a precious tool for forensic entomologists in Europe.

  3. Sex- and Size-Related Patterns of Carrion Visitation in Necrodes littoralis (Coleoptera: Silphidae) and Creophilus maxillosus (Coleoptera: Staphylinidae).

    PubMed

    Mądra-Bielewicz, Anna; Frątczak-Łagiewska, Katarzyna; Matuszewski, Szymon

    2016-12-28

    The estimation of postmortem interval (PMI) based on successional patterns of adult insects is largely limited, due to the lack of potential PMI markers. Sex and size of adult insects could be easily used for such estimation. In this study, sex- and size-related patterns of carrion attendance by adult insects were analyzed in Necrodes littoralis (Coleoptera: Silphidae) and Creophilus maxillosus (Coleoptera: Staphylinidae). For both species, abundance of males and females changed similarly during decomposition. A slightly female-biased sex ratio was recorded in N. littoralis. Females of N. littoralis started visiting carcasses, on average, one day earlier than males. There was a rise in size of males of N. littoralis at the end of decomposition, whereas for females of both species and males of C. maxillosus, no size-related patterns of carrion visitation were found. Current results demonstrate that size and sex of adult carrion beetles are poor indicators of PMI.

  4. Direct induced resistance in Oryza sativa to Spodoptera frugiperda.

    PubMed

    Stout, M J; Riggio, M R; Yang, Y

    2009-08-01

    Rice, Oryza sativa, is the most important staple food for a significant portion of the world's population. Despite the importance of rice, however, induced resistance to insects has not been thoroughly studied in rice; in fact, to our knowledge, direct induced resistance after injury by chewing insects has not been shown in rice. We conducted a series of experiments designed to characterize direct induced resistance in rice after feeding by larvae of the fall armyworm (Spodoptera frugiperda J. E. Smith) and application of jasmonic acid. Weight gains and relative growth rates of fall armyworm larvae were lower when fed leaves from plants previously damaged by armyworms than when fed leaves from undamaged plants. This response was stronger at a systemic spatial scale; that is, the induced resistance was stronger in newly emerged leaves not present at the time plants were damaged than in damaged leaves themselves. Armyworm growth rates were also reduced on foliage from plants treated with jasmonic acid, a hormone known to mediate plant responses to wounding. The response to injury by armyworm larvae and to exogenous jasmonic acid was stronger in transgenic rice plants in which levels of salicylic acid (a signaling molecule that inhibits jasmonic acid) were suppressed. These results show the existence of a direct induced resistance response in rice and suggest that this response to injury by a chewing insect may be mediated by jasmonic acid.

  5. [Effects of P and K fertilizer on content of coumarin and yield of Glehnia littoralis].

    PubMed

    Sun, Chuang-shu; Zheng, Kan; Li, Wei; Chen, Gui-lin; Yu, Rong; Yu, Jian-guo

    2015-09-01

    By a orthogonal experiment, the influence of different ratio of phosphorus and potassium fertilizers on imperatorin, isoimperatorin and psoralen contents and yield of Glehnia littoralis were studied. The results showed that root dry weight and the yield of G. littoralis increased when reasonably applied phosphorus fertilizer combined with potassium fertilizer within a certain range. And the influence of phosphorus fertilizer was greater than that of potassium fertilizer. The optimal value of root dry weight and yield achieved at both P2O5 360 kg x hm(-2), K2O 270 kg x hm(-2) and P2O5 360 kg x hm(-2), K2O 180 kg x hm(-2). The effects of different phosphorus and potassium treatments on the content of imperatorin, isoimperatorin and psoralen in G. littoralis were determined, which shows that the content increased with the moderate increase of phosphorus and potassium. And the effects of phosphorus fertilizer were more significantly. The isoimperatorin content achieved the largest value at P2O5 360 kg x hm(-2), K2O 270 kg x hm(-2), also a larger content of imperatorin and psoralen. The imperatorin content is the largest when applied P2O5 360 kg x hm(-2), K2O 180 kg x hm(-2), and the isoimperatorin content was higher as well. So that the treatment of P2O5 360 kg x hm(-2), K2O 180 kg x hm(-2) are suitable for promote to the agricultural production, which could improve the quality and yield of G. littoralis.

  6. Natural persistence of the coastal plant Glehnia littoralis along temperate sandy coasts

    PubMed Central

    Yang, Hong-Xiao; Chu, Jian-Min; Liu, Xiao-Shan

    2017-01-01

    We studied germination behaviors and persistence mechanism of wild Glehnia littoralis, a typical coastal species at temperate sandy coasts of the North Pacific Ocean, and tested the hypothesis that the coastal plants may have evolved special seeds adapting to the coasts, by which they recruit and persist easily, occupying the coasts as ideal habitats. In the Shandong Peninsula, China, we investigated temperature and moisture conditions of coast sand in relation to germination and evaluated effects of sand burial, seawater immersion and sowing time on germination. When germination began, daily dawn temperatures of sand were about 10 °C and daily noon temperatures were about 25 °C; the temperatures were not different in the sand <8 cm deep. The sand at these depths showed a significant difference in moisture contents. The seeds exhibited large germination rates if sand burial was at depths >= 3 cm and winter freezing was kept longer than 2.5 months. Seeds experiencing seawater immersion were able to germinate well. These evidences suggest that G. littoralis has evolved special seeds adapting to seawater dispersal and specific season rhythm. By the seeds, G. littoralis occupies temperate sandy coasts as ideal habitats to persist. PMID:28211487

  7. Anti-inflammatory and wound healing activities of Aloe littoralis in rats.

    PubMed

    Hajhashemi, V; Ghannadi, A; Heidari, A H

    2012-04-01

    Aloe littoralis Baker (Asphodelaceae family) is a well known plant in southern parts of Iran. Because of its use in Iranian folk medicine as a wound-healing agent, the present study was carried out to investigate anti-inflammatory and wound healing activities of this plant in Wistar rats. A. littoralis raw mucilaginous gel (ALRMG) and also two gel formulations prepared from the raw mucilaginous gel were used in this study. Gel formulations (12.5% and 100% v/w Aloe mucilage in a carbomer base) were applied topically (500 mg once daily) for 24 days in the thermal wound model. Also Aloe gel formulation (100%) and ALRMG (500 mg daily) were evaluated in incisional wound model. Carrageenan-induced paw edema was used to assess the anti-inflammatory effect of intraperitoneal injection of ALRMG. In burn wound, ALRMG and Aloe formulated gel (100%) showed significant (P<0.05) healing effect. Topical application of ALMRG and Aloe formulated gel (100%) promoted healing rate of incisional wound. In carrageenan test, ALRMG (2.5 and 5 ml/Kg) revealed significant (P<0.05) anti-inflammatory activity. Results showed that A. littoralis is a potential wound-healing and anti-inflammatory agent in rats. Further studies are needed to find out the mechanism of these biological effects and also the active constituents responsible for the effects.

  8. Anti-inflammatory and wound healing activities of Aloe littoralis in rats

    PubMed Central

    Hajhashemi, V.; Ghannadi, A.; Heidari, A.H.

    2012-01-01

    Aloe littoralis Baker (Asphodelaceae family) is a well known plant in southern parts of Iran. Because of its use in Iranian folk medicine as a wound-healing agent, the present study was carried out to investigate anti-inflammatory and wound healing activities of this plant in Wistar rats. A. littoralis raw mucilaginous gel (ALRMG) and also two gel formulations prepared from the raw mucilaginous gel were used in this study. Gel formulations (12.5% and 100% v/w Aloe mucilage in a carbomer base) were applied topically (500 mg once daily) for 24 days in the thermal wound model. Also Aloe gel formulation (100%) and ALRMG (500 mg daily) were evaluated in incisional wound model. Carrageenan-induced paw edema was used to assess the anti-inflammatory effect of intraperitoneal injection of ALRMG. In burn wound, ALRMG and Aloe formulated gel (100%) showed significant (P<0.05) healing effect. Topical application of ALMRG and Aloe formulated gel (100%) promoted healing rate of incisional wound. In carrageenan test, ALRMG (2.5 and 5 ml/Kg) revealed significant (P<0.05) anti-inflammatory activity. Results showed that A. littoralis is a potential wound-healing and anti-inflammatory agent in rats. Further studies are needed to find out the mechanism of these biological effects and also the active constituents responsible for the effects. PMID:23181083

  9. Defensive role of tomato polyphenol oxidases against cotton bollworm (Helicoverpa armigera) and beet armyworm (Spodoptera exigua).

    PubMed

    Bhonwong, Anongnut; Stout, Michael J; Attajarusit, Jutharat; Tantasawat, Piyada

    2009-01-01

    Tomato (Solanum lycopersicum) polyphenol oxidases (PPOs), enzymes that oxidize phenolics to quinones, have been implicated in plant resistance to insects. The role of PPO in resistance to cotton bollworm [Helicoverpa armigera (Hübner)] and beet armyworm [Spodoptera exigua (Hübner)] (Lepidoptera: Noctuidae) was evaluated. Consumption, weight gains, and mortality of larvae feeding on foliage of transgenic tomato lines overexpressing PPO (OP lines) and of larvae feeding on foliage of transgenic tomato lines with suppressed PPO (SP lines) were compared with consumption, weight gains, and mortality of larvae feeding on non-transformed (NT) plants. Increases in foliage consumption and weight gains were observed for cotton bollworms feeding on leaves of SP plants compared to NT and OP plants. PPO activity was negatively correlated with both weight gains and foliar consumption of cotton bollworm, substantiating the defensive role of PPO against this insect. Similarly, beet armyworm consumed less foliage (both young and old leaves) from OP plants than SP plants. Larvae feeding on OP leaves generally exhibited lower weight gains than those feeding on SP leaves. These results indicate that tomato PPO plays a role in resistance to both cotton bollworm and beet armyworm.

  10. Herbivore cues from the fall armyworm (Spodoptera frugiperda) larvae trigger direct defenses in maize.

    PubMed

    Chuang, Wen-Po; Ray, Swayamjit; Acevedo, Flor Edith; Peiffer, Michelle; Felton, Gary W; Luthe, Dawn S

    2014-05-01

    In addition to feeding damage, herbivores release cues that are recognized by plants to elicit defenses. Caterpillar oral secretions have been shown to trigger herbivore defense responses in several different plant species. In this study, the effects of two fall armyworm (Spodoptera frugiperda) oral secretions (saliva and regurgitant) on caterpillar defense responses in maize (Zea mays) were examined. Only minute amounts of regurgitant were deposited on the maize leaf during larval feeding bouts and its application to leaves failed to induce the expression of several herbivore defense genes. On the other hand, caterpillars consistently deposited saliva on leaves during feeding and the expression of several maize defense genes significantly increased in response to saliva application and larval feeding. However, feeding by ablated caterpillars with impaired salivation did not induce these defenses. Furthermore, bioassays indicated that feeding by unablated caterpillars significantly enhanced defenses when compared with that of ablated caterpillars. Another critical finding was that the maize genotype and stage of development affected the expression of defense genes in response to wounding and regurgitant treatments. These results demonstrate that fall armyworm saliva contains elicitors that trigger herbivore defenses in maize.

  11. Insecticidal Activity and Histopathological Effects of Vip3Aa Protein from Bacillus thuringiensis on Spodoptera litura.

    PubMed

    Song, Feifei; Lin, Yunfeng; Chen, Chen; Shao, Ensi; Guan, Xiong; Huang, Zhipeng

    2016-10-28

    Vegetative insecticidal proteins (Vips) are insecticidal proteins synthesized by Bacillus thuringiensis during the vegetative stage of growth. In this study, Vip3Aa protein, obtained by in vitro expression of the vip3Aa gene from B. thuringiensis WB5, displayed high insecticidal activity against Spodoptera litura aside from Spodoptera exigua and Helicoverpa armigera. Bioassay results showed that the toxicity of Vip3Aa protein against S. litura larvae statistically decreased along with the increase of the age of the larvae, with LC50 = 2.609 ng/cm(2) for neonatal larvae, LC50 = 28.778 ng/cm(2) for first instar larvae, LC50 = 70.460 ng/cm(2) for second instar larvae, and LC50 = 200.627 ng/cm(2) for third instar larvae. The accumulative mortality of 100% larvae appeared at 72 h for all instars of S. litura larvae, when feeding respectively with 83.22, 213.04, 341.40, and 613.20 ng/cm(2) of Vip3Aa toxin to the neonatal and first to third instar larvae. The histopathological effects of Vip3Aa toxin on the midgut epithelial cells of S. litura larvae was also investigated. The TEM observations showed wide damage of the epithelial cell in the midgut of S. litura larvae fed with Vip3Aa toxin.

  12. Expression and purification of recombinant nattokinase in Spodoptera frugiperda cells.

    PubMed

    Li, Xiaoxiang; Wang, Xiaoli; Xiong, Shaoling; Zhang, Jing; Cai, Litao; Yang, Yanyan

    2007-10-01

    A recombinant baculovirus, rv-egfp-NK, containing a reporter gene encoding the enhanced green fluorescent protein (EGFP), was used to express nattokinase (NK), a fibrinolytic enzyme, in Spodoptera frugiperda (SF-9) cells. The recombinant protein also included a histidine tag for purification using Ni(2+) resins. The recombinant NK, approximately 30 kDa, retained fibrinolytic activity (60 U/ml). The integration of the EGFP expression cassette in the Bac-to-Bac system is thus an effective method for the expression and purification of recombinant NK protein in Spodoptera frugiperda insect cells.

  13. Discrimination of Paederus fuscipes and Paederus littoralis by mtDNA-COI PCR-RFLP

    PubMed Central

    Bazrafkan, Sahar; Vatandoost, Hassan; Heydari, Abbas; Bakhshi, Hassan; Panahi-Moghadam, Somayeh; Hashemi-Aghdam, Saedeh; Mohtarami, Fatemeh; Rahimiforoushan, Abbas; Anlaandş, Sinan; Shayeghi, Mansoreh; Oshaghi, Mohammad Ali; Abtahi, Seyed Mohammad

    2016-01-01

    Background: Linear dermatitis is endemic in Iran where most cases occur in the Caspian Sea coast and Fars province. The disease is caused by beetles of the genus Paederus which are active from early spring to beginning of autumn although its incidence rises from May to August. The classic taxonomy of Paederus spp. is based on the male genitalia that is very complex and needs expertise. In this study, we report a DNA-based method to discriminate Paederus fuscipes and Paederus littoralis (=syn: P. lenkoranus, P. ilsae). Methods: Type specimens were collected from north and south of Iran. Molecular typing of the species was performed using restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction (PCR)-amplified fragments of mtDNA-COI. Results: Sequence analyses of the data obtained in this study showed significant DNA polymorphisms. There were 89 substitutions between COI sequences of the two species. The mtDNA-COI fragment comprises several useful species-specific restriction sites comprising HaeIII that could result in distinctively different species-specific PCR–RFLP profiles. The HaeIII enzyme cuts the 872 bp PCR amplicon of P. littoralis into 737 and 100 bp and two small nonvisible bands whereas it does not cut P. fuscipes amplicon into fragments. Conclusion: This study demonstrates that molecular typing is useful method and allows one to differentiate between two species and is recommended for discrimination of other Paederus species, which morphologically are indistinguishable or very difficult to be distinguished. PMID:28032097

  14. Pheromonal divergence between two strains of Spodoptera frugiperda

    USDA-ARS?s Scientific Manuscript database

    Abstract- Spodoptera frugiperda consists of two genetically and behaviorally different strains, the corn- and the rice-strain, which seem to be in the process of sympatric speciation. We investigated the role of strain-specific sexual communication as a prezygotic mating barrier between both strains...

  15. Responses of anthocyanin-producing and non-producing cells of Glehnia littoralis to radical generators.

    PubMed

    Kitamura, Yoshie; Ohta, Mina; Ikenaga, Toshihiko; Watanabe, Masami

    2002-01-01

    The responses of anthocyanin-producing (violet) and non-producing (white) cells of Glehnia littoralis to radical generators were compared. Cell growth, anthocyanin content, phenylalanine ammonia-lyase (PAL) activity and furanocoumarin production were determined after treatment with H(2)O(2), 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH), X-ray and yeast extract, independently. AAPH and H(2)O(2) repressed the growth of both violet and white cells, but violet cells grew better than white cells. On the other hand, the anthocyanin content in violet cells decreased. Neither X-ray nor yeast extract affected cell growth or pigment production. Treatment with H(2)O(2), yeast extract, and X-ray, but not AAPH, induced PAL activity and furanocoumarin production in white cell cultures, whereas violet cell cultures did not produce furanocoumarin following any of the treatment employed.

  16. Baculovirus-Induced Climbing Behavior Favors Intraspecific Necrophagy and Efficient Disease Transmission in Spodoptera exigua

    PubMed Central

    Rebolledo, Dulce; Guevara, Roger; Murillo, Rosa

    2015-01-01

    Shortly prior to death, many species of Lepidoptera infected with nucleopolyhedrovirus climb upwards on the host plant. This results in improved dissemination of viral occlusion bodies over plant foliage and an increased probability of transmission to healthy conspecific larvae. Following applications of Spodoptera exigua multiple nucleopolyhedrovirus for control of Spodoptera exigua on greenhouse-grown sweet pepper crops, necrophagy was observed by healthy S. exigua larvae that fed on virus-killed conspecifics. We examined whether this risky behavior was induced by olfactory or phagostimulant compounds associated with infected cadavers. Laboratory choice tests and olfactometer studies, involving infected and non-infected cadavers placed on spinach leaf discs, revealed no evidence for greater attraction of healthy larvae to virus-killed over non-infected cadavers. Physical contact or feeding on infected cadavers resulted in a very high incidence of transmission (82–93% lethal disease). Observations on the behavior of S. exigua larvae on pepper plants revealed that infected insects died on the uppermost 10% of foliage and closer to the plant stem than healthy conspecifics of the same stage, which we considered clear evidence of baculovirus-induced climbing behavior. Healthy larvae that subsequently foraged on the plant were more frequently observed closer to the infected than the non-infected cadaver. Healthy larvae also encountered and fed on infected cadavers significantly more frequently and more rapidly than larvae that fed on non-infected cadavers. Intraspecific necrophagy on infected cadavers invariably resulted in virus transmission and death of the necrophagous insect. We conclude that, in addition to improving the dissemination of virus particles over plant foliage, baculovirus-induced climbing behavior increases the incidence of intraspecific necrophagy in S. exigua, which is the most efficient mechanism of transmission of this lethal pathogen. PMID

  17. Chemical composition of volatiles from Opuntia littoralis, Opuntia ficus-indica, and Opuntia prolifera growing on Catalina Island, California.

    PubMed

    Wright, Cynthia R; Setzer, William N

    2014-01-01

    The essential oils from the cladodes of Opuntia littoralis, Opuntia ficus-indica and Opuntia prolifera growing wild on Santa Catalina Island, California, were obtained by hydrodistillation and analysed by gas chromatography-mass spectrometry (GC-MS). Terpenoids were the dominant class of volatiles in O. littoralis, with the two main components being the furanoid forms of cis-linalool oxide (10.8%) and trans-linalool oxide (8.8%). Fatty acid-derived compounds dominated the essential oil of O. ficus-indica with linoleic acid (22.3%), palmitic acid (12.7%), lauric acid (10.5%) and myristic acid (4.2%) as major fatty acids. O. prolifera oil was composed of 46.6% alkanes and the primary hydrocarbon component was heptadecane (19.2%). Sixteen compounds were common to all the three Opuntia species.

  18. Temporal changes in elemental composition in decomposing filamentous algae (Cladophora glomerata and Pilayella littoralis) determined with PIXE and PIGE.

    PubMed

    Lill, J-O; Salovius-Laurén, S; Harju, L; Rajander, J; Saarela, K-E; Lindroos, A; Heselius, S-J

    2012-01-01

    Particle-induced X-ray emission and particle-induced gamma-ray emission spectrometry were successfully applied in a study of the elemental composition of decomposing filamentous algae. Fresh brown (Pilayella littoralis) and green (Cladophora glomerata) algal materials were placed in cages at 4m depth in a water column of 8m in the Archipelago Sea, northern Baltic Sea. Every second week decaying algae were sampled from the cages to allow measurements of changes in the elemental compositions. In the study of the elemental losses the concentrations were compensated for the mass reduction. The results show that sulphur, chlorine and partly potassium were lost during decomposition of P. littoralis and C. glomerata. Most of the other elements studied were recovered in the remaining algal mass. Special attention was paid to sorption and desorption of elements, including metal binding capacity, in the decaying algal materials. The affinity order of different cations to the two algal species was established by calculation of conditional distribution coefficients, D'(M). For instance for P. littoralis the following series of binding strength (affinity) of cations were obtained: Al>Ti>Fe > Mn>Ni, Cu>Ba, Cr, Zn>Rb>K, Sr>Pb>Ca>Na>Mg. Notably is that the binding strength of strontium was more than 10 times higher for P. littoralis than for C. glomerata. Due to their high binding capacity and good affinity and selectivity for heavy metal ions these algae have great potential as biological sorbents. Large variations in elemental content during decomposition complicate the use of algae for environmental monitoring.

  19. Toxic effects of Citrus aurantium and C. limon essential oils on Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Villafañe, Emilio; Tolosa, Diego; Bardón, Alicia; Neske, Adriana

    2011-09-01

    Citrus aurantium and C. limon were selected in the search for natural plant insecticides. The essential oils of C. aurantium and C. limon and ethanol extracts of the seeds, pulp, albedo, and peel of C. aurantium were incorporated into the larval diet of the lepidopteran pest Spodoptera frugiperda. Larval and pupal mortality were quantified and adult malformation was observed. C aurantium essential oil had antifeedant action and the mixture of albedo ethanol extract and C aurantium essential oil had toxic effects on S. frugiperda larvae at early stages, when they had not yet produced major damage to the crop. Our results indicated that a mixture of ethanol extract of albedo and C. aurantium essential oil (250 microg of extract mix per g of diet) deterred feeding by 46% and had the highest larval mortality (100%) of the materials tested. The peel extract (250 microg per g of diet) produced an increment in growth rate and diet consumption. However, 40% of the larval and 45% of the pupal populations died after 96 h of treatment. The blend of essential oil and C. aurantium albedo ethanol extract showed the lowest consumption and a poor nutrient conversion into biomass. Finally, the presence of D-limonene and nootkatone in the peel ethanol extract, and C. limon and C. aurantium essential oils, may be the cause of the response in the feeding behavior and toxic effects found on S. frugiperda.

  20. [Antifeeding effects of crude lantadene from Lantana camara on Plutella xylostella and Spodoptera litura larvae].

    PubMed

    Dong, Yizhi; Zhang, Maoxin; Ling, Bing

    2005-12-01

    In this study, crude lantadene was extracted from Lantana canmara leaves, and its antifeeding effects on Plutella xylostella and Spodoptera litura larvae were tested. In no-choice test, crude lantadene at 1.6 mg x ml(-1) concentration had antifeeding effects on the 2nd instar P. xylostella larvae and 1st instar S. litura larvae, with the antifeeding rate being 62.4% and 33.1%, respectively within 48 h. In choice test, even a low concentration (0.4 mg x ml(-1)) crude lantadene still had anti-feeding effects on the 2nd instar P. xylostella larvae, and the antifeeding rate at 0.4, 0.8 and 1.6 mg x ml(-1) concentration was 52.7%, 55.5% and 78.9%, respectively. Crude lantadene only at 1.6 mg x ml(-1) concentration had anti-feeding effects on the 1st instar S. litura larvae, and the antifeeding rate was 33.0%. For the 2nd instar S. litura larvae, crude lantadene had no antifeeding effects both in no-choice and in choice test.

  1. Effects of cyanogenic plants on fitness in two host strains of the fall armyworm (Spodoptera frugiperda).

    PubMed

    Hay-Roe, Mirian M; Meagher, Robert L; Nagoshi, Rodney N

    2011-12-01

    The generalist moth, Spodoptera frugiperda (J. E. Smith) consists of two genetic subgroups (host strains) that differ in their distribution among host plant species. The corn strain prefers crop plants such as corn, sorghum, and cotton, while the rice strain is found in small grasses such as Cynodon spp. and rice. Little is known about the physiological factors that drive this host preference. Here, we report a feeding study with natural host plants and an artificial diet containing cyanide. We found that corn, two Cynodon spp. (bermudagrass C. dactylon (L.) Persoon, 'NuMex Sahara', and stargrass C. nlemfuensis var. nlemfuensis Vanderyst, 'Florona'), and a hybrid between bermudagrass and stargrass, 'Tifton 85', exhibited differences in the concentration of the cyanogenic precursors or cyanogenic potential (HCNp) and the release of hydrogen cyanide per unit time or cyanogenic capacity (HCNc). Corn plants released low levels of hydrogen cyanide, while stargrass had greater HCNp/HCNc than bermudagrass and 'Tifton 85'. Feeding studies showed that corn strain larvae experienced higher mortality than the rice strain when fed stargrass or artificial diet supplemented with cyanide. Also, corn strain larvae excreted higher levels of cyanogenic compounds than the rice strain when fed Cynodon spp. These differences in excretion suggest potential disparities in cyanide metabolism between the two strains. We hypothesize that differences in the susceptibility to cyanide levels in various host plants could play a role in driving strain divergence and what appears to be the incipient speciation of this moth.

  2. Comparative analysis of lycorine in wild plant and callus culture samples of Hymenocallis littoralis by HPLC-UV method.

    PubMed

    Subramaniam, Sreeramanan; Sundarasekar, Jeevandran; Sahgal, Geethaa; Murugaiyah, Vikneswaran

    2014-01-01

    The Hymenocallis littoralis, an ornamental and medicinal plant, had been traditionally used for wound healing. In the present study, an analytical method using HPLC with ultraviolet detection was developed for the quantification of lycorine in the extracts of different parts of wild plant and tissue culture samples of H. littoralis. The separation was achieved using a reversed-phase column. The method was found to be accurate, repeatable, and sensitive for the quantification of minute amount of lycorine present in the samples. The highest lycorine content was found in the bulb extract (2.54 ± 0.02 μg/mg) whereas the least was in the root extract (0.71 ± 0.02 μg/mg) of the wild plants. Few callus culture samples had high content of lycorine, comparable to that of wild plants. The results showed that plant growth regulators, 2,4-dichlorophenoxyacetic acid (2,4-D) alone at 4.5 μM (2.58 ± 0.38 μg/mg) or a combination of 2,4-D at 9.00 μM with 4.5 μM of 6-benzylaminopurine (BAP), were the optimum concentrations for the production of high lycorine (2.45 ± 0.15 μg/mg) content in callus culture. The present analytical method could be of value for routine quantification of lycorine in the tissue culture production and standardization of the raw material or extracts of H. littoralis.

  3. Elicitors of tansy volatiles from cotton leafworm larval oral secretion.

    PubMed

    Mack, Lienhard; Gros, Petra; Burkhardt, Jens; Seifert, Karlheinz

    2013-12-01

    The feeding of Spodoptera littoralis and Autographa gamma caterpillars on tansy leaves led to a complete different release of volatile monoterpenes, sesquiterpenes, and hexenyl alkanoates. Volatiles were collected from S. littoralis and A. gamma larvae damaged, mechanically wounded, and excised tansy leaves by closed loop stripping analysis. The qualitative and quantitative determination of the volatiles were done by GC-MS- and GC-measurements. The oligosaccharides sucrose, raffinose, stachyose, and verbascose have been detected in oral secretion of the caterpillars of the cotton leafworm S. littoralis. When applied to damaged leaves of tansy plants, these oligosaccharides induce the tansy leaves to emit a similar volatile blend as the feeding of S. littoralis larvae. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. [Oviposition, development, and reproduction of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) fed on different hosts of economic importance].

    PubMed

    Barros, Eduardo M; Torres, Jorge B; Bueno, Adeney F

    2010-01-01

    The host selection for oviposition by Spodoptera frugiperda (J.E. Smith) among corn, millet, cotton and soybean, and its relationship with the biological characteristics were investigated. Free and non-choice tests for oviposition using plots containing five plants each, from each host in plastic greenhouse, resulted in similar oviposition preference among the host plants. In addition, selected biological characteristics of S. frugiperda were determined in the laboratory with larvae feeding on host leaves, and the combination of leaf and cotton boll. Neonate larvae exhibited low success of colonization on cotton boll compared to the leaves of all other hosts. Spodoptera frugiperda fed only on cotton bolls exhibited longer larval and pupal development, and longer adult life span; however with similar egg production. Larvae fed cotton leaves during six days and then transferred to cotton bolls, however, exhibited development and reproduction similar to those reared on corn or only on cotton leaves. Therefore, the variations on immature stages of S. frugiperda were not related with host selection for oviposition which was similar among the studied hosts. Based on our data, the millet as a winter, rotational, and cover crop is a potential host for S. frugiperda, while leaves and cotton bolls were diets of intermediate suitability as compared to corn and soybean leaves.

  5. Feeding deterrence and inhibitory effects of bee balm (Monarda didyma) leaves on fall armyworm

    USDA-ARS?s Scientific Manuscript database

    The fall armyworm [Spodoptera frugiperda (J.E. Smith)] is a serious pest of many field and horticulture crops. Because of the many advantages for the use of plant-derived pesticides, we tested whether bee balm (Monarda didyma L.) leaves could have feeding deterrence on fall armyworm. When S. frugipe...

  6. Development and feeding of fall armyworm, on Miscanthus x giganteus and switchgrass

    USDA-ARS?s Scientific Manuscript database

    Observations of fall armyworm [Spodoptera frugiperda (J.E. Smith)] larvae infesting plots of Miscanthus x giganteus Greef and Deuter ex Hodkinson and Renvoize prompted laboratory-based tests of survival, development and feeding preferences on leaf tissue from M. x giganteus and switchgrass (Panicum ...

  7. Cannibalism and virus production in Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) larvae fed with two leaf substrates inoculated with Baculovirus spodoptera.

    PubMed

    Valicente, F H; Tuelher, E S; Pena, R C; Andreazza, R; Guimarães, M R F

    2013-04-01

    Cannibalism in the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (FAW), is a limiting factor in a baculovirus production system. To detect the impact of cannibalism, a two-step bioassay was conducted with different larval ages of FAW fed on two food sources (corn and castor bean leaves) contaminated with the S. frugiperda multiple-embedded nucleopolyhedrovirus. In a first bioassay, the food source affected the cannibalism, being higher for all larval ages tested (5-, 6- and 7-day-old larvae) in larvae fed on corn than on those fed on castor bean leaves. Larval mortality, weight equivalent and larval equivalents (LEs) per hectare decreased as the larval age increased. Larval weight, occlusion bodies (OBs)/larva and total OBs increased when the larval age increased. In a second bioassay, in which only 6- and 7-day-old larvae were used because of the performance in the first bioassay, the cannibalism rates were affected by the interaction between food sources and time of feeding (48 and 72 h), reaching the highest values for 6- and 7-day-old larvae fed on corn leaves for 72 h. Mortality of the FAW was affected by the interaction between food sources, larval age and time of feeding. The lowest mortalities were on 7-day-old larvae when they were fed on castor bean leaves for 48 and 72 h. Larval weight, OBs/larva, total OBs and LEs were affected by the interaction between food sources and larval age. A significant correlation was observed between larval weight and OBs/larva that fed on both food sources, suggesting that larval weight can be used to achieve a concentration to be sprayed in 1 ha.

  8. Extractives of seeds of the meliaceae: Effects onSpodoptera frugiperda (J.E. Smith),Acalymma vittatum (F.), andArtemia salina Leach.

    PubMed

    Mikolajczak, K L; Reed, D K

    1987-01-01

    Hexane and ethanol extracts of seeds from 22 species of plants of the family Meliaceae from a number of countries were prepared. The extracts were submitted to antifeedant and toxicity bioassays utilizing fall armyworm [Spodoptera frugiperda (J.E. Smith)] (Lepidoptera: Noctuidae) larvae and striped cucumber beetle [Acalymma vittatum (F.)] (Coleoptera: Chrysomelidae) adults. Toxicity tests were also performed with brine shrimp,Anemia salina Leach. Feeding inhibition and mortality produced by some of these extracts were comparable to and, in certain cases, slightly greater than the effects produced by comparable neem (Azadiracta indica A. Juss.) seed preparations. Brine shrimp toxicity data do not extrapolate to insect activity, and vice versa.

  9. [The effect of food containing Cestrum paquii (Solanaceae) extract on various damaging Lepidoptera].

    PubMed

    Chaieb, I; Ben Halima-Kamel, M; Ben Hamouda, M H

    2001-01-01

    The repulsive activity of Cestrum parquii on the feeding behaviour of Pieris brassicae L. and Spodoptera littoralis Boisduval was studied. Antifeedant effect was observed at regular intervals during a week. Meal uptake was stopped after the first day, showing a strongly antifeedant effect of C. parquii extract on these two species. The impact of C. parquii with different concentrations of dry extract (2, 4, 8, 16, 32%) delayed the larval growth of Spodoptera littoralis Boisduval compared to untreated insects. Abnormal metamorphosis was observed with concentrations of 8 and 16% leading to death and abnormal morphogenesis. The antifeedant activity of C. parquii was also observed in S. littoralis and measured by the evolution of food uptake and the weight of larva. Effect seemed to be proportional to extract concentration in the diet. High concentration (32%) stopped growth in the earlier instar.

  10. Mitochondrial Genomes Suggest Rapid Evolution of Dwarf California Channel Islands Foxes (Urocyon littoralis)

    PubMed Central

    Hofman, Courtney A.; Rick, Torben C.; Hawkins, Melissa T. R.; Funk, W. Chris; Ralls, Katherine; Boser, Christina L.; Collins, Paul W.; Coonan, Tim; King, Julie L.; Morrison, Scott A.; Newsome, Seth D.; Sillett, T. Scott; Fleischer, Robert C.; Maldonado, Jesus E.

    2015-01-01

    Island endemics are typically differentiated from their mainland progenitors in behavior, morphology, and genetics, often resulting from long-term evolutionary change. To examine mechanisms for the origins of island endemism, we present a phylogeographic analysis of whole mitochondrial genomes from the endangered island fox (Urocyon littoralis), endemic to California’s Channel Islands, and mainland gray foxes (U. cinereoargenteus). Previous genetic studies suggested that foxes first appeared on the islands >16,000 years ago, before human arrival (~13,000 cal BP), while archaeological and paleontological data supported a colonization >7000 cal BP. Our results are consistent with initial fox colonization of the northern islands probably by rafting or human introduction ~9200–7100 years ago, followed quickly by human translocation of foxes from the northern to southern Channel Islands. Mitogenomes indicate that island foxes are monophyletic and most closely related to gray foxes from northern California that likely experienced a Holocene climate-induced range shift. Our data document rapid morphological evolution of island foxes (in ~2000 years or less). Despite evidence for bottlenecks, island foxes have generated and maintained multiple mitochondrial haplotypes. This study highlights the intertwined evolutionary history of island foxes and humans, and illustrates a new approach for investigating the evolutionary histories of other island endemics. PMID:25714775

  11. Mitochondrial genomes suggest rapid evolution of dwarf California Channel Islands foxes (Urocyon littoralis).

    PubMed

    Hofman, Courtney A; Rick, Torben C; Hawkins, Melissa T R; Funk, W Chris; Ralls, Katherine; Boser, Christina L; Collins, Paul W; Coonan, Tim; King, Julie L; Morrison, Scott A; Newsome, Seth D; Sillett, T Scott; Fleischer, Robert C; Maldonado, Jesus E

    2015-01-01

    Island endemics are typically differentiated from their mainland progenitors in behavior, morphology, and genetics, often resulting from long-term evolutionary change. To examine mechanisms for the origins of island endemism, we present a phylogeographic analysis of whole mitochondrial genomes from the endangered island fox (Urocyon littoralis), endemic to California's Channel Islands, and mainland gray foxes (U. cinereoargenteus). Previous genetic studies suggested that foxes first appeared on the islands >16,000 years ago, before human arrival (~13,000 cal BP), while archaeological and paleontological data supported a colonization >7000 cal BP. Our results are consistent with initial fox colonization of the northern islands probably by rafting or human introduction ~9200-7100 years ago, followed quickly by human translocation of foxes from the northern to southern Channel Islands. Mitogenomes indicate that island foxes are monophyletic and most closely related to gray foxes from northern California that likely experienced a Holocene climate-induced range shift. Our data document rapid morphological evolution of island foxes (in ~2000 years or less). Despite evidence for bottlenecks, island foxes have generated and maintained multiple mitochondrial haplotypes. This study highlights the intertwined evolutionary history of island foxes and humans, and illustrates a new approach for investigating the evolutionary histories of other island endemics.

  12. Origins and antiquity of the island fox ( Urocyon littoralis) on California's Channel Islands

    NASA Astrophysics Data System (ADS)

    Rick, Torben C.; Erlandson, Jon M.; Vellanoweth, René L.; Braje, Todd J.; Collins, Paul W.; Guthrie, Daniel A.; Stafford, Thomas W., Jr.

    2009-03-01

    The island fox ( Urocyon littoralis) is one of few reportedly endemic terrestrial mammals on California's Channel Islands. Questions remain about how and when foxes first colonized the islands, with researchers speculating on a natural, human-assisted, or combined dispersal during the late Pleistocene and/or Holocene. A natural dispersal of foxes to the northern Channel Islands has been supported by reports of a few fox bones from late Pleistocene paleontological localities. Direct AMS 14C dating of these "fossil" fox bones produced dates ranging from ˜ 6400 to 200 cal yr BP, however, postdating human colonization of the islands by several millennia. Although one of these specimens is the earliest securely dated fox from the islands, these new data support the hypothesis that Native Americans introduced foxes to all the Channel Islands in the early to middle Holocene. However, a natural dispersal for the original island colonization cannot be ruled out until further paleontological, archaeological, and genetic studies (especially aDNA [ancient DNA]) are conducted.

  13. Systemic Amyloid A Amyloidosis in Island Foxes (Urocyon littoralis): Severity and Risk Factors.

    PubMed

    Gaffney, P M; Witte, C; Clifford, D L; Imai, D M; O'Brien, T D; Trejo, M; Liberta, F; Annamalai, K; Fändrich, M; Masliah, E; Munson, L; Sigurdson, C J

    2016-05-01

    Systemic amyloid A (AA) amyloidosis is highly prevalent (34%) in endangered island foxes (Urocyon littoralis) and poses a risk to species recovery. Although elevated serum AA (SAA) from prolonged or recurrent inflammation predisposes to AA amyloidosis, additional risk factors are poorly understood. Here we define the severity of glomerular and medullary renal amyloid and identify risk factors for AA amyloidosis in 321 island foxes necropsied from 1987 through 2010. In affected kidneys, amyloid more commonly accumulated in the medullary interstitium than in the glomeruli (98% [n= 78 of 80] vs 56% [n= 45], respectively;P< .0001), and medullary deposition was more commonly severe (19% [n= 20 of 105]) as compared with glomeruli (7% [n= 7];P= .01). Univariate odds ratios (ORs) of severe renal AA amyloidosis were greater for short- and long-term captive foxes as compared with free-ranging foxes (ORs = 3.2, 3.7, respectively; overall P= .05) and for females as compared with males (OR = 2.9;P= .05). Multivariable logistic regression revealed that independent risk factors for amyloid development were increasing age class (OR = 3.8;P< .0001), San Clemente Island subspecies versus San Nicolas Island subspecies (OR = 5.3;P= .0003), captivity (OR = 5.1;P= .0001), and nephritis (OR = 2.3;P= .01). The increased risk associated with the San Clemente subspecies or captivity suggests roles for genetic as well as exogenous risk factors in the development of AA amyloidosis.

  14. Nests, eggs, and nestlings of the Restinga Antwren Formicivora littoralis (Aves: Thamnophilidae).

    PubMed

    Chaves, Flávia G; Vecchi, Maurício B; Laurindo, Thiago F S; Alves, Maria Alice S

    2013-01-01

    We describe the nest, eggs, and nestlings of the Restinga Antwren (Formicivora littoralis), an endangered bird of Restinga ecosystem (sandy coastal plain vegetation) that is endemic to Rio de Janeiro state. Twelve nests were found at the edges of trails or natural gaps at Massambaba Restinga region, in different supporting plants and heights from the ground (X ± SD 1.27 ± 0.97 m, range 0.27 to 3.45 m). Nests were cup-shaped and were in horizontal forks attached to branches at three to five points with whitish, soft, and thin cotton-like vegetable fiber. The nests' cup shape and measurements were similar to congeneric species, but nest material was different. Eggs were white with brown spots concentrated on the large end or around the middle, giving the appearance of a rough brown ring. Their mean (± SD) minimum diameter was 13.1 ± 0.34 mm, with maximum diameter of 18.0 ± 0.38 mm, and mass of 1.7 ± 0.18 g (n = 8). We found two nestlings completely naked on their first day after hatching.

  15. Indirect interactions between arbuscular mycorrhizal fungi and Spodoptera exigua alter photosynthesis and plant endogenous hormones.

    PubMed

    He, Lei; Li, Changyou; Liu, Runjin

    2017-08-01

    Peanut (Arachis hypogaea Linn. cv: Luhua 11) and tomato (Lycopersicon esculentum Mill. cv: Zhongshu 4) were inoculated with arbuscular mycorrhizal fungi (AMF) Funneliformis mosseae BEG167 (Fm), Rhizophagus intraradices BEG141 (Ri), and Glomus versiforme Berch (Gv), and/or Spodoptera exigua (S. exigua) under greenhouse conditions. Results indicated that feeding by S. exigua had little influence on colonization of peanut plants by AMF, but improved colonization of tomato by Fm and Gv. Feeding by S. exigua had little influence on leaf net photosynthetic rate, transpiration rate, and stomatal conductance of nonmycorrhizal peanut plants but significantly improved net photosynthetic rate and transpiration rate of mycorrhizal plants of both hosts. AMF with or without S. exigua inoculation improved host plant photosynthetic characteristics, growth, and hormone status. Fm showed maximum beneficial effects, followed by Gv. The concentrations and ratios of phytohormones abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellin (GA), zeatin riboside (ZR), and jasmonic acid (JA) in the leaves of the host plants were changed due to the interaction between AMF and S. exigua. Generally, AMF with or without S. exigua inoculation increased the concentrations of GA, ZR, and JA and the ratios of IAA/ABA, GA/ABA, ZR/ABA, and IAA + GA + ZR/ABA, while feeding by S. exigua on nonmycorrhizal plants showed the opposite effect. The concentration of JA in the leaves of peanut and tomato inoculated with Fm or Fm + S. exigua was 1.9 and 1.9 times and 2.5 and 2.7 times, respectively, greater than that of the controls inoculated with neither. There was a negative correlation between the JA concentration and the survival percentage of S. exigua larva. We conclude that indirect interactions between AMF and insect herbivores changed the photosynthetic and hormone characteristics, and ratios of phytohormones, thereby revealing mechanisms of belowground-aboveground interactions.

  16. Oviposition by Spodoptera exigua on Nicotiana attenuata primes induced plant defence against larval herbivory.

    PubMed

    Bandoly, Michele; Hilker, Monika; Steppuhn, Anke

    2015-08-01

    Plants exhibit multifarious defence traits against herbivory that are constitutively expressed or induced upon attack. Insect egg deposition often precedes impending larval attack, and several plants can increase their resistance against larvae after experiencing the oviposition by an herbivore. The nature of such oviposition-mediated resistance remains unknown, and here we aim to determine plant traits that explain it. We test whether oviposition on a host plant can induce plant defence responses or enhance (prime) the induction of defence traits in response to larval herbivory. We exposed Nicotiana attenuata plants to oviposition by moths of a generalist herbivore, Spodoptera exigua. Its larvae suffered higher mortality, retarded development and inflicted less feeding damage on oviposition-experienced than on oviposition-unexperienced plants. While oviposition alone did not induce any of the examined defence traits, oviposited plants exhibited a stronger inducibility of known defence traits, i.e. caffeoylputrescine (CP) and trypsin protease inhibitors (TPIs). We found no effects of oviposition on phytohormone levels, but on the feeding-inducible accumulation of the transcription factor NaMyb8 that is governing biosynthesis of phenylpropanoid-polyamine conjugates, including CP. Comparison of larval performance on wild-type plants, CP-deficient plants (silenced NaMyb8 gene), and TPI-deficient plants (silenced NaPI gene) revealed that priming of plant resistance to larvae by prior oviposition required NaMyb8-mediated defence traits. Our results show that plants can use insect egg deposition as a warning signal to prime their feeding-induced defence.

  17. Efficiency of Intergeneric Recombinants Between Bacillus Thuringiensis and Bacillus Subtilis for Increasing Mortality Rate in Cotten Leaf Worm

    NASA Astrophysics Data System (ADS)

    AlOtaibi, Saad Aied

    2012-12-01

    In this study , two strains of Bacillus belonging to two serotypes and four of their transconjugants were screened with respect to their toxicity against lepidopterous cotton pest. . Bacterial transconjugants isolated from conjugation between both strains were evaluated for their transconjugant efficiency caused mortality in Spodoptera littoralis larvae . Two groups of bioinsecticides ; crystals , crystals and spores have been isolated from Bacillusstrains and their transconjugants . Insecticidal crystal protein ( ICP ) was specific for lepidopteran insects because of the toxin sufficient both for insect specificity and toxicity . The toxicities of these two groups against larvae of Spodoptera littoralis was expressed as transconjugant efficiency , which related to the mean number of larvae died expressed as mortality percentage . The results showed transconjugant efficiency in reducing the mean number of Spodoptera littoralis larvae feeding on leaves of Ricinus communis sprayed with bioinsecticides of Bt transconjugants. Most values of positive transconjugant efficiency related to increasing mortality percentage are due to toxicological effects appeared in response to the treatments with crystals + endospores than that of crystals alone .This indicated that crystals + endospores was more effective for increasing mortality percentage than that resulted by crystals . Higher positive transconjugant efficiency in relation to the mid parents and better parent was appeared at 168 h of treatment . The results indicated that recombinant Bacillus thuringiensis are important control agents for lepidopteran pests , as well as , susceptibility decreased with larval development . The results also suggested a potential for the deployment of these recominant entomopathogens in the management of Spodoptera. littoralis larvae .

  18. Toxicity of nine insecticides on four natural enemies of Spodoptera exigua

    PubMed Central

    Liu, Yongqiang; Li, Xiangying; Zhou, Chao; Liu, Feng; Mu, Wei

    2016-01-01

    Spodoptera exigua, which feeds on various crops worldwide, has natural enemies that are susceptible to the insecticides used against S. exigua. We investigate the toxicity and residue risk of 9 insecticides on the development of H. axyridis, C. sinica, S. manilae and T. remus. S. manilae and T. remus adults were sensitive to all 9 insecticides (LC50 less than 2.75 mg a.i. liter−1), while H. axyridis and C. sinica adults were less sensitive (LC50 between 6 × 10−5 mg a.i. liter−1 and 78.95 mg a.i. liter−1). Emamectin benzoate, spinosad, indoxacarb, alpha-cypermethrin, chlorfenapyr and chlorantraniliprole showed no toxicity on H. axyridis, C. sinica, S. manilae and T. remus pupae with the recommended field concentrations. The risk analysis indicated that chlorantraniliprole is harmless to larvae of four natural enemies and adult of H. axyridis, C. sinica and S. manilae. Emamectin benzoate and spinosad had higher safety to the development of H. axyridis, C. sinica, S. manilae and T. remus with the risk duration less than 4d. Indoxacarb, tebufenozide, chlorfenapyr, methomyl, alpha-cypermethrin and chlorpyrifos showed dangerously toxic and long risk duration on S. manilae and T. remus adults. PMID:27958333

  19. Endophyte-mediated interactions between cauliflower, the herbivore Spodoptera litura, and the ectoparasitoid Bracon hebetor.

    PubMed

    Kaur, Tamanreet; Singh, Bahaderjeet; Kaur, Amarjeet; Kaur, Sanehdeep

    2015-10-01

    Fungal endosymbionts in plants may influence interactions among plants, herbivores and their parasitoids through the production of secondary metabolites. We used a lepidopteran pest and its generalist parasitoid to test the effect of endophyte-infected plants on a third trophic level. Endophytic fungi, Aspergillus flavus and Aspergillus niger, isolated from Acacia arabica, were used to infect cauliflower plants. We found that the presence of the endophyte in the plants significantly extended the development period of Spodoptera litura (Fab.) larvae. Feeding of the host on endophyte-infected plants further adversely affected the development and performance of its parasitoid, Bracon hebetor (Say). A negative impact was also recorded for longevity and fecundity of endophyte-naive parasitoid females due to the parasitization of host larvae fed on endophyte-infected plants. The presence of endophytes in the diet of the host larvae significantly prolonged the development of the parasitoid. A strong detrimental effect was also recorded for larval survival and emergence of parasitoid adults. The longevity and parasitism rate of female wasps were reduced significantly due to the ingestion of endophyte-infected cauliflower plants by S. litura larvae. Overall, we found that both endophytic fungi had a negative impact on the parasitoid.

  20. Toxicity of nine insecticides on four natural enemies of Spodoptera exigua.

    PubMed

    Liu, Yongqiang; Li, Xiangying; Zhou, Chao; Liu, Feng; Mu, Wei

    2016-12-13

    Spodoptera exigua, which feeds on various crops worldwide, has natural enemies that are susceptible to the insecticides used against S. exigua. We investigate the toxicity and residue risk of 9 insecticides on the development of H. axyridis, C. sinica, S. manilae and T. remus. S. manilae and T. remus adults were sensitive to all 9 insecticides (LC50 less than 2.75 mg a.i. liter(-1)), while H. axyridis and C. sinica adults were less sensitive (LC50 between 6 × 10(-5) mg a.i. liter(-1) and 78.95 mg a.i. liter(-1)). Emamectin benzoate, spinosad, indoxacarb, alpha-cypermethrin, chlorfenapyr and chlorantraniliprole showed no toxicity on H. axyridis, C. sinica, S. manilae and T. remus pupae with the recommended field concentrations. The risk analysis indicated that chlorantraniliprole is harmless to larvae of four natural enemies and adult of H. axyridis, C. sinica and S. manilae. Emamectin benzoate and spinosad had higher safety to the development of H. axyridis, C. sinica, S. manilae and T. remus with the risk duration less than 4d. Indoxacarb, tebufenozide, chlorfenapyr, methomyl, alpha-cypermethrin and chlorpyrifos showed dangerously toxic and long risk duration on S. manilae and T. remus adults.

  1. Bitter gourd proteinase inhibitors: potential growth inhibitors of Helicoverpa armigera and Spodoptera litura.

    PubMed

    Telang, Manasi; Srinivasan, Ajay; Patankar, Aparna; Harsulkar, Abhay; Joshi, Vijay; Damle, Archana; Deshpande, Vasanti; Sainani, Mohini; Ranjekar, Prabhakar; Gupta, Gorakh; Birah, Ajanta; Rani, Seema; Kachole, Manavendra; Giri, Ashok; Gupta, Vidya

    2003-07-01

    Proteinase inhibitors (PIs) from the seeds of bitter gourd (Momordica charantia L.) were identified as strong inhibitors of Helicoverpa armigera gut proteinases (HGP). Biochemical investigations showed that bitter gourd PIs (BGPIs) inhibited more than 80% HGP activity. Electrophoretic analysis revealed the presence of two major proteins (BGPI-1 and-2) and two minor proteins (BGPI-3 and-4) having inhibitory activity against both trypsin and HGP. The major isoforms BGPI-1 and BGPI-2 have molecular mass of 3.5 and 3.0 kDa, respectively. BGPIs inhibited HGP activity of larvae fed on different host plants, on artificial diet with or without added PIs and proteinases excreted in fecal matter. Degradation of BGPI-1 by HGP showed direct correlation with accumulation of BGPI-2-like peptide, which remained stable and active against high concentrations of HGP up to 3 h. Chemical inhibitors of serine proteinases offered partial protection to BGPI-1 from degradation by HGP, suggesting that trypsin and chymotrypsin like proteinases are involved in degradation of BGPI-1. In larval feeding studies, BGPIs were found to retard growth and development of two lepidopteran pests namely Helicoverpa armigera and Spodoptera litura. This is the first report showing that BGPIs mediated inhibition of insect gut proteinases directly affects fertility and fecundity of both H. armigera and S. litura. The results advocate use of BGPIs to introduce insect resistance in otherwise susceptible plants.

  2. Discovery and characterization of field resistance to Bt maize: Spodoptera frugiperda (Lepidoptera: Noctuidae) in Puerto Rico.

    PubMed

    Storer, Nicholas P; Babcock, Jonathan M; Schlenz, Michele; Meade, Thomas; Thompson, Gary D; Bing, James W; Huckaba, Randy M

    2010-08-01

    Transgenic maize, Zea mays L., event TC1507 produces the Cry1F protein to provide protection from feeding by several important lepidopteran pests, including Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Reports of reduced field performance against this species in Puerto Rico were investigated, and laboratory bioassays showed that S. frugiperda collected from the affected area exhibited lower sensitivity to the Cry1F protein compared with typical colonies from other regions. The resistance was shown to be autosomally inherited and highly recessive. The Puerto Rico colony was shown to be moderately less sensitive than susceptible laboratory strains to Cry1Ab and Cry1Ac, but the differences in sensitivity were dramatically smaller than for Cry1F. Potential contributory factors to the emergence of resistance to Cry1F in Puerto Rico populations of S. frugiperda include the tropical island geography, unusually large population sizes in 2006, and drought conditions reducing the availability of alternative hosts. In response to this resistance incident, the technology providers have stopped commercial sales of TC1507 maize in Puerto Rico pending potential reversion to susceptibility.

  3. Secondary metabolites from Glycine soja and their growth inhibitory effect against Spodoptera litura.

    PubMed

    Zhou, Yan-Ying; Luo, Shi-Hong; Yi, Ting-Shuang; Li, Chun-Huan; Luo, Qian; Hua, Juan; Liu, Yan; Li, Sheng-Hong

    2011-06-08

    The wild soybean (Glycine soja Sieb. et Zucc) has been reported to be relatively resistant to insect and pathogenic pests. However, the responsible secondary metabolites in the aerial part of this important plant are largely unknown. From the aerial part of G. soja, 13 compounds were isolated and identified, including seven isoflavonoids (1-7), a cyclitol (8), two sterol derivatives (9 and 10), and three triterpenoids (11-13). Compound 7 is a new isoflavonoid, and compounds 9 and 10 are reported as natural products for the first time. The growth inhibitory activity of 1, 3, 4, and 8 against the larvae of Spodoptera litura was investigated. The most abundant isoflavonoid in the aerial part of G. soja, daidzein (1), which could not be metabolized by S. litura, was found to inhibit the insect larvae growth significantly in 3 days after feeding diets containing the compound. Compounds 3, 4, and 8, which could be partially or completely metabolized, were inactive. Our results suggested that the isoflavonoid daidzein (1) might function as a constitutive defense component in G. soja against insect pests.

  4. Immature stages of Spodoptera eridania (Lepidoptera: Noctuidae): developmental parameters and host plants.

    PubMed

    Montezano, Débora Goulart; Specht, Alexandre; Sosa-Gómez, Daniel Ricardo; Roque-Specht, Vânia Ferreira; de Barros, Neiva Monteiro

    2014-01-01

    This study aimed to detail the temporal and morphological parameters of the immature stages of southern armyworm Spodoptera eridania (Stoll, 1782) with larvae feed on artificial diet, under controlled conditions (25 ± 1°C, 70 ± 10% relative humidity and 14-h photophase) and gather information about their larval host plants. The viability of the egg, larval, pupal, and prepupal stages was 97.82, 93.62, 96.42, and 97.03%, respectively. The average duration of the egg, larval, pupal, and pre-pupal stages was 4.00, 16.18, 1.58, and 9.17 d, respectively. During the larval stage, 43.44% of females passed through seven instars, observing that the female's development was significant slower than males. The female larvae that developed through six and seven instars exhibited a mean growth rate of 1.52 and 1.44, respectively. Female pupae were significantly larger, exhibiting faster development than males. The rearing method proved to be adequate, providing more detailed observations of the biological cycle, especially at the larval stage, and resulting in an overall survival of almost 85%. Two hundred two plant species belonging to 58 families are listed as natural hosts for S. eridania, mainly including Asteraceae, Fabaceae, Solanaceae, Poaceae, Amaranthaceae, and Malvaceae. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  5. Overexpression of Tyrosine hydroxylase and Dopa decarboxylase associated with pupal melanization in Spodoptera exigua

    PubMed Central

    Liu, Sisi; Wang, Mo; Li, Xianchun

    2015-01-01

    Melanism has been found in a wide range of species, but the molecular mechanisms involved remain largely elusive. In this study, we studied the molecular mechanisms of the pupal melanism in Spodoptera exigua. The full length cDNA sequences of tyrosine hydroxylase (TH) and dopa decarboxylase (DDC), two key enzymes in the biosynthesis pathway of melanin, were cloned, and their temporal expression patterns in the integument were compared during the larval-pupal metamorphosis process of the S. exigua wild type (SEW) and melanic mutant (SEM) strains. No amino acid change in the protein sequence of TH and DDC was found between the two strains. Both DDC and TH were significantly over-expressed in the integument of the SEM strain at late-prepupa and 0 h pupa, respectively, compared with those of the SEW strain. Feeding 5th instar larvae of SEM with diets incorporated with 1 mg/g of the DDC inhibitor L-α-Methyl-DOPA and 0.75 mg/g of the TH inhibitor 3-iodo-tyrosine (3-IT) resulted in 20% pupae with partially-rescued phenotype and 68.2% of pupae with partially- or fully-rescued phenotype, respectively. These results indicate that overexpressions of TH and DDC are involved in the pupal melanization of S. exigua. PMID:26084938

  6. Exogenous and endogenous protease inhibitors in the gut of the fall armyworm larvae, Spodoptera frugiperda.

    PubMed

    Lwalaba, Digali; Weidlich, Sandy; Hoffmann, Klaus H; Woodring, Joseph

    2010-06-01

    A dose-dependent inhibition of endogenous trypsin and aminopeptidase occurs in the lumen of Spodoptera frugiperda after feeding L6 larvae exogenous inhibitors soybean trypsin inhibitor (SBTI), tosyl-L-lysine chloromethyl ketone-HCl (TLCK), or bestatin, respectively, for 3 days. TLCK inhibits trypsin in tissue extracts and in secretions more strongly than SBTI. The aminopeptidase released into the lumen (containing the peritrophic membrane) is strongly inhibited by bestatin, but the membrane-bound enzyme is not. A bound enzyme may be more resistant to an inhibitor than unbound. A cross-class elevation of aminopeptidase activity occurs in response to ingested trypsin inhibitor, but there was no cross-class effect of aminopeptidase inhibitor (bestatin) on trypsin activity. An endogenous trypsin and aminopeptidase inhibitor is present in the lumen and ventricular cells. The strength of the endogenous trypsin inhibition seems to be in the same range as that resulting from ingestion of the exogenous inhibitor SBTI. In some insect species, considerable trypsin secretion occurs in unfed as well as in fed animals, and endogenous protease inhibitors might function to protect the ventricular epithelium by inactivation of trypsin when less food is available.

  7. Induction of apoptosis by the tropical seaweed Pylaiella littoralis in HT-29 cells via the mitochondrial and MAPK pathways

    NASA Astrophysics Data System (ADS)

    Ye, Bo-Ram; Kim, Junseong; Kim, Min-Sun; Jang, Jiyi; Oh, Chulhong; Kang, Do-Hyung; Qian, Zhong-Ji; Jung, Won-Kyo; Choi, Il-Whan; Heo, Soo-Jin

    2013-12-01

    We demonstrated that an extract from Pylaiella littoralis, collected from the Federate States of Micronesia (FSM), could inhibit the proliferation of tumor cells. P. littoralis extract (PLE) showed anti-proliferative activities in the tumorigenic cells tested, ranging from 20.2% to 67.9%. The highest inhibitory activity, in HT-29 cells, was selected for further experiments. PLE showed no cytotoxic effect in normal cells and inhibited the growth of HT-29 cells depending on concentration and incubation time. PLE-treated HT-29 cells showed the typical morphological characteristics of apoptosis, such as apoptotic body formation and DNA fragmentation. PLE also induced mitochondrial membrane potential depolarization and resulted in increased mitochondrial membrane permeability, compared with untreated cells. PLE decreased Bcl-2 protein and increased Bax protein expression, activating caspase-3 and poly (ADP-ribose) polymerase (PARP) expression via the caspase pathway. PLE also increased the phosphorylation of c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK), and it reduced cell viability in treatment cells with specific inhibitors such as PD98059 (a specific inhibitor of ERK), SP600125 (a specific inbibitor of JNK), and SB 203580 (a specific inbibitor of p38 MAPK). via the the mitogen-activated protein kinases (MAPKs) pathway. These results suggest that PLE inhibits the proliferation of HT-29 cells by affecting the caspase and MAPK pathways involved in the induction of apoptosis. Thus, we suggest that P. littoralis extract might be potential candidate agents for the treatment of human colorectal cancer.

  8. Comparative Analysis of Lycorine in Wild Plant and Callus Culture Samples of Hymenocallis littoralis by HPLC-UV Method

    PubMed Central

    Sahgal, Geethaa; Murugaiyah, Vikneswaran

    2014-01-01

    The Hymenocallis littoralis, an ornamental and medicinal plant, had been traditionally used for wound healing. In the present study, an analytical method using HPLC with ultraviolet detection was developed for the quantification of lycorine in the extracts of different parts of wild plant and tissue culture samples of H. littoralis. The separation was achieved using a reversed-phase column. The method was found to be accurate, repeatable, and sensitive for the quantification of minute amount of lycorine present in the samples. The highest lycorine content was found in the bulb extract (2.54 ± 0.02 μg/mg) whereas the least was in the root extract (0.71 ± 0.02 μg/mg) of the wild plants. Few callus culture samples had high content of lycorine, comparable to that of wild plants. The results showed that plant growth regulators, 2,4-dichlorophenoxyacetic acid (2,4-D) alone at 4.5 μM (2.58 ± 0.38 μg/mg) or a combination of 2,4-D at 9.00 μM with 4.5 μM of 6-benzylaminopurine (BAP), were the optimum concentrations for the production of high lycorine (2.45 ± 0.15 μg/mg) content in callus culture. The present analytical method could be of value for routine quantification of lycorine in the tissue culture production and standardization of the raw material or extracts of H. littoralis. PMID:24895650

  9. Genetic diversity of the nucleocapsid protein gene of hippeastrum chlorotic ringspot virus from Hymenocallis littoralis in southern China.

    PubMed

    Li, Q; Xu, Y; Zhu, M; Dong, Y; Hu, J; Li, Y; Liu, Y

    2017-01-01

    Hymenocallis littoralis growing in southern China has been recently extensively damaged by virus-like symptoms of necrosis, chlorosis, and ringspot. Of 44 plant samples collected from Yunnan, Guangxi, Guangdong, and Fujian provinces in southern China, 32 were infected with hippeastrum chlorotic ringspot virus (HCRV). Phylogenetic analysis based on the N gene divided the virus samples into two branches suggesting a geographic distribution attributed to the initial stage of a founder effect. The N gene was under purifying selection pressure and most of the deleterious mutants had been removed. Both the population dynamics and genetic analyses suggested that populations of HCRV in southern China are spreading.

  10. Optimization of Methodology for Rearing Spodoptera albula on Artificial Diet.

    PubMed

    Di Bello, M M; Souza, B H S; Nogueira, L; Ribeiro, Z A; Eduardo, W I; Boiça Júnior, A L

    2017-03-08

    Advances in techniques for rearing insects on artificial diets are fundamental to solving issues of basic and applied entomology. In this study, we evaluated the development of Spodoptera albula (Walker) (Lepidoptera: Noctuidae) on three artificial diets used for other species of Lepidoptera, at three larval densities, and two densities of adult couples housed in oviposition cages of two sizes, with the aim of optimizing methodology for rearing S. albula in the laboratory. Biological parameters were recorded from S. albula, and a fitness index was calculated based on the larval survival and duration and weight of pupae. The total and daily oviposition was recorded using 5 or 10 adult couples of S. albula housed in two cage sizes. Concentrations of total nitrogen and protein in the tested diets were determined. Development of S. albula was completed in all artificial diets; however, the diet used for rearing Anticarsia gemmatalis (Hübner) larvae was the most suitable for S. albula, yielding intermediate development time and higher survival relative to the other diets. Individualization of larvae favored S. albula development by producing overall greater weights of larvae and pupae, higher survival rates, and longer adult longevity. Cage size and number of couples per cage did not influence S. albula fecundity in the experiment conditions. Spodoptera albula can be satisfactorily reared on the artificial diet used for A. gemmatalis, using one larva per tube, and either density of adults at any cage size. Additional amendments are needed in the rearing methodology to achieve optimal conditions for larval development to adulthood.

  11. Use of benzimidazole agar plates to assess fall armyworm (Lepidoptera: Noctuidae) feeding on excised maize and sorghum leaves

    USDA-ARS?s Scientific Manuscript database

    The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is an economically significant pest of sorghum and maize. To screen sorghum and maize germplasm for resistance to fall armyworm feeding, field, greenhouse, or lab bioassays are often utilized individually or in combinatio...

  12. Biochemical and hematologic reference intervals for the endangered island fox (Urocyon littoralis).

    PubMed

    Inoue, Hiromi; Clifford, Deana L; Vickers, T Winston; Coonan, Timothy J; Garcelon, David K; Borjesson, Dori L

    2012-07-01

    Hematologic and serum biochemical data collected must be interpreted by comparison with normal reference intervals generated from healthy animals, within a similar population, because many blood parameters are influenced by diet, environment, and stress. Species-specific reference intervals for the endangered island fox (Urocyon littoralis) are not available. We reviewed hematology and serum biochemistry panels from 280 island foxes sampled from 1999-2008 and established normal reference intervals from clinically healthy foxes using a nonparametric approach. Blood parameters were analyzed for differences in age, sex, island of origin, and captivity status. Alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities, as well as calcium and phosphorus concentrations, were significantly higher in juveniles than in adults, but total protein and globulin concentration was lower for juveniles than for adults. Lymphocyte and eosinophil counts, and blood urea nitrogen (BUN) concentration, in foxes from the northern Channel islands of California, USA (Santa Cruz, Santa Rosa, and San Miguel) were higher when compared with foxes from Santa Catalina Island to the south. Higher lymphocyte and eosinophil numbers in the northern island foxes may be associated with increased levels of parasitism on the northern islands. Differences in BUN concentration in both free-ranging and captive foxes may reflect dietary differences among islands. Although aggressive conservation programs have been enacted, island foxes are still susceptible to infectious and neoplastic diseases and, potentially, to toxins. Island fox species-specific reference intervals will enable managers and veterinarians to better care for sick and injured foxes and will contribute to future population health monitoring.

  13. First microsatellites developed from Spodoptera frugiperda and their potential use for population genetics

    USDA-ARS?s Scientific Manuscript database

    This is the first report of sequence-specific microsatellite markers (SSRs) of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), an economically important pest of the American continent. We developed 178 microsatellite markers using pyrosequencing, and screened 15 individuals from 8 colonies ...

  14. First microsatellites from Spodoptera frugiperda (Lepidoptera: Noctuidae) and their potential use for population genetics

    USDA-ARS?s Scientific Manuscript database

    This is the first report of sequence-specific microsatellite markers (SSRs) of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), an economically important pest of the American continent. We developed 178 microsatellite markers using pyrosequencing, and screened 15 individuals from 8 isofamili...

  15. The Influence of an Invasive Shrub, Buddleja Davidii on a Native Shrub, Griselinia Littoralis Transplanted into a New Zealand Floodplain Chronosequence

    EPA Science Inventory

    Griselinia littoralis, a native New Zealand shrub, was planted into a chronosequence (0 to 8 yrs since flooding) dominated by the non-indigenous shrub, Buddleja davidii in three New Zealand floodplains to determine to what extent facilitation and competitive inhibition may influe...

  16. The Influence of an Invasive Shrub, Buddleja Davidii on a Native Shrub, Griselinia Littoralis Transplanted into a New Zealand Floodplain Chronosequence

    EPA Science Inventory

    Griselinia littoralis, a native New Zealand shrub, was planted into a chronosequence (0 to 8 yrs since flooding) dominated by the non-indigenous shrub, Buddleja davidii in three New Zealand floodplains to determine to what extent facilitation and competitive inhibition may influe...

  17. Independence of genetic geographical variation between photoperiodic diapause, circadian eclosion rhythm, and Thr-Gly repeat region of the period gene in Drosophila littoralis.

    PubMed

    Lankinen, P; Forsman, P

    2006-02-01

    Drosophila littoralis is a latitudinally widespread European species of the Drosophila virilis group. The species has ample genetic variation in photoperiodism (adult diapause) and circadian rhythmicity (pupal eclosion rhythm), with adaptive latitudinal clines in both of them. The possible common genetic basis between the variability of photoperiodism and circadian rhythms was studied by a long-term crossing experiment. A northern strain (65 degrees N) having long critical day length (CDL = 19.9 h) for diapause, early phase of the entrained rhythm in LD 3:21 (psi(LD3:21) = 12.3 h), and short period (tau= 18.8 h) of the free-running rhythm for the eclosion rhythm was crossed with a southern strain (42 degrees N) having short CDL (12.4 h), late eclosion phase (psi(LD3:21) = 20.2 h), and long period (tau= 22.8 h). After 54 generations, including free recombination, artificial selection, and genetic drift, a novel strain resulted, having even more "southern" diapause and more "northern" eclosion rhythm characteristics than found in any of the geographical strains. The observed complete separation of eclosion rhythm characteristics from photoperiodism is a new finding in D. littoralis; in earlier studies followed for 16 generations, the changes had been mostly parallel. Evidently, the genes controlling the variability of the eclosion rhythm and photoperiodism in D. littoralis are different but closely linked. To test for the possible gene loci underlying the observed geographical variability, the period gene was studied in 10 strains covering all the known clock variability in D. littoralis. The authors sequenced the most suspected Thr-Gly region, which is known to take part in the adaptive clock variability in Drosophila melanogaster. No coding differences were found in the strains, showing that this region is not included in the adaptive clock variability in D. littoralis.

  18. Ruta graveolens Extracts and Metabolites against Spodoptera frugiperda.

    PubMed

    Ayil-Gutiérrez, Benjamin A; Villegas-Mendoza, Jesús M; Santes-Hernndez, Zuridai; Paz-González, Alma D; Mireles-Martínez, Maribel; Rosas-García, Ninfa M; Rivera, Gildardo

    2015-11-01

    The biological activity of Ruta graveolens leaf tissue extracts obtained with different solvents (ethyl acetate, ethanol, and water) and metabolites (psoralen, 2- undecanone and rutin) against Spodoptera frugiperda was evaluated. Metabolites levels in extracts were quantified by HPLC and GC. Ethyl acetate and ethanol extracts showed 94% and 78% mortality, respectively. Additionally, psoralen metabolite showed a high mortality as cypermethrin. Metabolite quantification in extracts shows the presence of 2-undecanone (87.9 µmoles mg(-1) DW), psoralen (3.6 µmoles mg(-1) DW) and rutin (0.001 pmoles mg(-1) DW). We suggest that these concentrations of 2-undecanone and psoralen in R. graveolens leaf tissue extracts could be responsible for S. frugiperda mortality.

  19. Mortality Dynamics of Spodoptera frugiperda (Lepidoptera: Noctuidae) Immatures in Maize

    PubMed Central

    Varella, Andrea Corrêa; Menezes-Netto, Alexandre Carlos; Alonso, Juliana Duarte de Souza; Caixeta, Daniel Ferreira; Peterson, Robert K. D.; Fernandes, Odair Aparecido

    2015-01-01

    We characterized the dynamics of mortality factors affecting immature developmental stages of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Multiple decrement life tables for egg and early larval stages of S. frugiperda in maize (Zea mays L.) fields were developed with and without augmentative releases of Telenomus remus Nixon (Hymenoptera: Platygastridae) from 2009 to 2011. Total egg mortality ranged from 73 to 81% and the greatest egg mortality was due to inviability, dislodgement, and predation. Parasitoids did not cause significant mortality in egg or early larval stages and the releases of T. remus did not increase egg mortality. Greater than 95% of early larvae died from predation, drowning, and dislodgment by rainfall. Total mortality due to these factors was largely irreplaceable. Results indicate that a greater effect in reducing generational survival may be achieved by adding mortality to the early larval stage of S. frugiperda. PMID:26098422

  20. Interactions between density, home range behaviors, and contact rates in the Channel Island fox (Urocyon littoralis)

    PubMed Central

    Sanchez, Jessica N; Hudgens, Brian R

    2015-01-01

    Many of the mechanisms underlying density-dependent regulation of populations, including contest competition and disease spread, depend on contact among neighboring animals. Understanding how variation in population density influences the frequency of contact among neighboring animals is therefore an important aspect to understanding the mechanisms underlying, and ecological consequences of, density-dependent regulation. However, contact rates are difficult to measure in the field and may be influenced by density through multiple pathways. This study explored how local density affects contact rates among Channel Island foxes (Urocyon littoralis) through two pathways: changes in home range size and changes in home range overlap. We tracked 40 radio-collared foxes at four sites on San Clemente Island, California. Fox densities at the four sites ranged from 2.8 ± 1.28 to 42.8 ± 9.43 foxes/km2. Higher fox densities were correlated with smaller home ranges (R2 = 0.526, F1,38 = 42.19, P < 0.001). Thirty foxes wore collars that also contained proximity loggers, which recorded the time and duration of occasions when collared foxes were within 5 m of one another. Contact rates between neighboring fox dyads were positively correlated with home range overlap (R2 = 0.341, P = 0.008), but not fox density (R2 = 0.012, P = 0.976). Individuals at high densities had more collared neighbors with overlapping home ranges (R2 = 0.123, P = 0.026) but not an increase in the amount of contact between individual neighbors. This study was the first time contact rates were directly measured and compared to density and home range overlap. Results suggest that foxes exhibit a threshold in their degree of tolerance for neighbors, overlap is a reliable index of the amount of direct contact between island foxes, and disease transmission rates will likely scale with fox density. PMID:26120435

  1. Interactions between density, home range behaviors, and contact rates in the Channel Island fox (Urocyon littoralis).

    PubMed

    Sanchez, Jessica N; Hudgens, Brian R

    2015-06-01

    Many of the mechanisms underlying density-dependent regulation of populations, including contest competition and disease spread, depend on contact among neighboring animals. Understanding how variation in population density influences the frequency of contact among neighboring animals is therefore an important aspect to understanding the mechanisms underlying, and ecological consequences of, density-dependent regulation. However, contact rates are difficult to measure in the field and may be influenced by density through multiple pathways. This study explored how local density affects contact rates among Channel Island foxes (Urocyon littoralis) through two pathways: changes in home range size and changes in home range overlap. We tracked 40 radio-collared foxes at four sites on San Clemente Island, California. Fox densities at the four sites ranged from 2.8 ± 1.28 to 42.8 ± 9.43 foxes/km(2). Higher fox densities were correlated with smaller home ranges (R (2) = 0.526, F 1,38 = 42.19, P < 0.001). Thirty foxes wore collars that also contained proximity loggers, which recorded the time and duration of occasions when collared foxes were within 5 m of one another. Contact rates between neighboring fox dyads were positively correlated with home range overlap (R (2)  = 0.341, P = 0.008), but not fox density (R (2)  = 0.012, P = 0.976). Individuals at high densities had more collared neighbors with overlapping home ranges (R (2)  = 0.123, P = 0.026) but not an increase in the amount of contact between individual neighbors. This study was the first time contact rates were directly measured and compared to density and home range overlap. Results suggest that foxes exhibit a threshold in their degree of tolerance for neighbors, overlap is a reliable index of the amount of direct contact between island foxes, and disease transmission rates will likely scale with fox density.

  2. Spatial variation in foliar chemicals within radish (Raphanus sativus) plants and their effects on performance of Spodoptera litura.

    PubMed

    Yadav, Jitendra; Tan, Ching-Wen; Hwang, Shaw-Yhi

    2010-12-01

    Foliar chemicals are variable within a plant and this may affect herbivore feeding preference. This study was carried out to quantify concentrations of primary (nitrogen, water, and total nonstructural carbohydrates) and secondary substances (sinigrin) in young and old leaves of Raphanus sativus L. and to evaluate performance and survival of a generalist herbivore Spodoptera litura F. feeding on them. Forty to 50-d-old R. sativus plants were used in both foliar chemical analysis and insect performance bioassays. Leaves located on the third to the sixth node from the base of the plant were defined as old leaves and the remaining leaves (from seventh node to the plant apex) of the plant were referred as young leaves in this study. All foliar chemicals except water differed significantly between young and old leaves. Moreover, young leaves were more nutritious but much more defended, based on sinigrin content, against S. litura than old leaves. Performance and survival of S. litura were reduced on young leaves as compared with old leaves. Male and female larval duration only differed significantly on young leaves. Female larval development time was longer than male development time on young leaves, but not on older leaves. Therefore, this study revealed that defenses in young leaves have differential effects upon male and female S. litura. © 2010 Entomological Society of America

  3. Control of the release of digestive enzymes in the larvae of the fall armyworm, Spodoptera frugiperda.

    PubMed

    Lwalaba, Digali; Hoffmann, Klaus H; Woodring, Joseph

    2010-01-01

    There is a basal level of enzyme activity for trypsin, aminopeptidase, amylase, and lipase in the gut of unfed larval (L6) Spodoptera frugiperda. Trypsin activity does not decrease with non-feeding, possibly because of the low protein levels in plants along with high amino acid requirements for growth and storage (for later reproduction in adults). Therefore, trypsin must always be present so that only a minimal protein loss via egestion occurs. Larvae, however, adjust amylase activity to carbohydrate ingestion, and indeed amylase activity is five-fold higher in fed larvae compared to unfed larvae. Gut lipase activity is low, typical of insects with a high carbohydrate diet. A flat-sheet preparation of the ventriculus was used to measure the release of enzymes in response to specific nutrients and known brain/gut hormones in S. frugiperda. Sugars greatly increase (>300%) amylase release, but starch has no effect. Proteins and amino acids have little or no effect on trypsin or aminopeptidase release. The control of enzyme release in response to food is likely mediated through neurohormones. Indeed, an allatostatin (Spofr-AS A5) inhibits amylase and trypsin, and allatotropin (Manse- AT) stimulates amylase and trypsin release. Spofr-AS A5 also inhibits ileum myoactivity and Manse-AT stimulates myoactivity. The epithelial secretion rate of amylase and trypsin was about 20% of the amount of enzyme present in the ventricular lumen, which, considering the efficient counter-current recycling of enzymes, suggests that the secretion rate is adequate to replace egested enzymes. (c) 2009 Wiley Periodicals, Inc.

  4. The male and female complete mitochondrial genome sequences of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798) (Bivalvia: Unionidae).

    PubMed

    Froufe, Elsa; Gan, Han Ming; Lee, Yin Peng; Carneiro, João; Varandas, Simone; Teixeira, Amílcar; Zieritz, Alexandra; Sousa, Ronaldo; Lopes-Lima, Manuel

    2015-08-19

    Freshwater mussels of the family Unionidae exhibit a particular form of mitochondria inheritance called double uniparental inheritance (DUI), in which the mitochondria are inherited by both male and female parents. The (M)ale and (F)emale mitogenomes are highly divergent within species. In the present study, we determine and describe the complete M and F mitogenomes of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798). The complete M and F mitogenomes sequences are 16 451 bp and 15 787 bp in length, respectively. Both F and M have the same gene content: 13 protein-coding genes (PCGs), 22 transfer RNA (trn) and 2 ribosomal RNA (rrn) genes. Bayesian analyses based on the concatenated nucleotide sequences of 12 PCGs and 2 rrn genes of both genomes, including mitogenome sequences available from related species, were performed. Male and Female lineages are monophyletic within the family, but reveal distinct phylogenetic relationships.

  5. The male and female complete mitochondrial genome sequences of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798) (Bivalvia: Unionidae).

    PubMed

    Froufe, Elsa; Gan, Han Ming; Lee, Yin Peng; Carneiro, João; Varandas, Simone; Teixeira, Amílcar; Zieritz, Alexandra; Sousa, Ronaldo; Lopes-Lima, Manuel

    2016-09-01

    Freshwater mussels of the family Unionidae exhibit a particular form of mitochondria inheritance called double uniparental inheritance (DUI), in which the mitochondria are inherited by both male and female parents. The (M)ale and (F)emale mitogenomes are highly divergent within species. In the present study, we determine and describe the complete M and F mitogenomes of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798). The complete M and F mitogenomes sequences are 16 451 bp and 15 787 bp in length, respectively. Both F and M have the same gene content: 13 protein-coding genes (PCGs), 22 transfer RNA (trn) and 2 ribosomal RNA (rrn) genes. Bayesian analyses based on the concatenated nucleotide sequences of 12 PCGs and 2 rrn genes of both genomes, including mitogenome sequences available from related species, were performed. Male and Female lineages are monophyletic within the family, but reveal distinct phylogenetic relationships.

  6. The male and female complete mitochondrial genome sequences of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798) (Bivalvia: Unionidae).

    PubMed

    Froufe, Elsa; Gan, Han Ming; Lee, Yin Peng; Carneiro, João; Varandas, Simone; Teixeira, Amílcar; Zieritz, Alexandra; Sousa, Ronaldo; Lopes-Lima, Manuel

    2015-08-14

    Freshwater mussels of the family Unionidae exhibit a particular form of mitochondria inheritance called double uniparental inheritance (DUI), in which the mitochondria are inherited by both male and female parents. The (M)ale and (F)emale mitogenomes are highly divergent within species. In the present study, we determine and describe the complete M and F mitogenomes of the Endangered freshwater mussel Potomida littoralis (Cuvier, 1798). The complete M and F mitogenomes sequences are 16 451 bp and 15 787 bp in length, respectively. Both F and M have the same gene content: 13 protein-coding genes (PCGs), 22 transfer RNA (trn) and 2 ribosomal RNA (rrn) genes. Bayesian analyses based on the concatenated nucleotide sequences of 12 PCGs and 2 rrn genes of both genomes, including mitogenome sequences available from related species, were performed. Male and Female lineages are monophyletic within the family, but reveal distinct phylogenetic relationships.

  7. XENOTRANSFUSION IN AN ISLAND FOX (UROCYON LITTORALIS CLEMENTAE) USING BLOOD FROM A DOMESTIC DOG (CANIS LUPUS FAMILIARIS).

    PubMed

    Martony, Molly E; Krause, Kristian J; Weldy, Scott H; Simpson, Stephen A

    2016-09-01

    Successful xenotransfusion in an island fox ( Urocyon littoralis clementae) has not been previously reported but may be necessary in an emergency. An 11-yr-old male, intact, captive island fox was exhibiting clinical signs of rattlesnake envenomation including hypoperfusion, tachypnea, facial edema, and multifocal facial and cervical ecchymosis. Blood work revealed severe thrombocytopenia (18 K/μl) and anemia (Hct 15.8%). A presumptive diagnosis of rattlesnake ( Crotalus sp.) envenomation was made. Initial treatment included oxygen therapy, fluid therapy, antibiotics, antacids, pain medications, and polyvalent crotalid anti-venom. Emergency xenotransfusion using whole blood (45 ml) from a domestic dog was used due to worsening clinical signs from anemia. No acute or delayed transfusion reactions were observed in the fox and the patient made a full recovery 5 days later. Successful xenotransfusion in an island fox using whole blood from a domestic dog ( Canis lupus familiaris) is possible and may be lifesaving.

  8. Temperature Affects the Use of Storage Fatty Acids as Energy Source in a Benthic Copepod (Platychelipus littoralis, Harpacticoida)

    PubMed Central

    Werbrouck, Eva; Van Gansbeke, Dirk; Vanreusel, Ann; De Troch, Marleen

    2016-01-01

    The utilization of storage lipids and their associated fatty acids (FA) is an important means for organisms to cope with periods of food shortage, however, little is known about the dynamics and FA mobilization in benthic copepods (order Harpacticoida). Furthermore, lipid depletion and FA mobilization may depend on the ambient temperature. Therefore, we subjected the temperate copepod Platychelipus littoralis to several intervals (3, 6 and 14 days) of food deprivation, under two temperatures in the range of the normal habitat temperature (4, 15°C) and under an elevated temperature (24°C), and studied the changes in FA composition of storage and membrane lipids. Although bulk depletion of storage FA occurred after a few days of food deprivation under 4°C and 15°C, copepod survival remained high during the experiment, suggesting the catabolization of other energy sources. Ambient temperature affected both the degree of FA depletion and the FA mobilization. In particular, storage FA were more exhausted and FA mobilization was more selective under 15°C compared with 4°C. In contrast, depletion of storage FA was limited under an elevated temperature, potentially due to a switch to partial anaerobiosis. Food deprivation induced selective DHA retention in the copepod’s membrane, under all temperatures. However, prolonged exposure to heat and nutritional stress eventually depleted DHA in the membranes, and potentially induced high copepod mortality. Storage lipids clearly played an important role in the short-term response of the copepod P. littoralis to food deprivation. However, under elevated temperature, the use of storage FA as an energy source is compromised. PMID:26986852

  9. Temperature Affects the Use of Storage Fatty Acids as Energy Source in a Benthic Copepod (Platychelipus littoralis, Harpacticoida).

    PubMed

    Werbrouck, Eva; Van Gansbeke, Dirk; Vanreusel, Ann; De Troch, Marleen

    2016-01-01

    The utilization of storage lipids and their associated fatty acids (FA) is an important means for organisms to cope with periods of food shortage, however, little is known about the dynamics and FA mobilization in benthic copepods (order Harpacticoida). Furthermore, lipid depletion and FA mobilization may depend on the ambient temperature. Therefore, we subjected the temperate copepod Platychelipus littoralis to several intervals (3, 6 and 14 days) of food deprivation, under two temperatures in the range of the normal habitat temperature (4, 15 °C) and under an elevated temperature (24 °C), and studied the changes in FA composition of storage and membrane lipids. Although bulk depletion of storage FA occurred after a few days of food deprivation under 4 °C and 15 °C, copepod survival remained high during the experiment, suggesting the catabolization of other energy sources. Ambient temperature affected both the degree of FA depletion and the FA mobilization. In particular, storage FA were more exhausted and FA mobilization was more selective under 15 °C compared with 4 °C. In contrast, depletion of storage FA was limited under an elevated temperature, potentially due to a switch to partial anaerobiosis. Food deprivation induced selective DHA retention in the copepod's membrane, under all temperatures. However, prolonged exposure to heat and nutritional stress eventually depleted DHA in the membranes, and potentially induced high copepod mortality. Storage lipids clearly played an important role in the short-term response of the copepod P. littoralis to food deprivation. However, under elevated temperature, the use of storage FA as an energy source is compromised.

  10. Metabolic insights into the cold survival strategy and overwintering of the common cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae).

    PubMed

    Zhu, Wei; Zhang, Huan; Meng, Qian; Wang, Menglong; Zhou, Guiling; Li, Xuan; Wang, Hongtuo; Miao, Lin; Qin, Qilian; Zhang, Jihong

    2017-07-01

    The common cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), is a destructive pest in Asia. Although overwintering in the field has not been reported for this species, their larvae are capable of long-term survival in fluctuating temperatures, i.e., 5°C (12h) plus 13°C (12h), if food is available. With an increase in climate change due to global warming and the widespread use of greenhouses, further understanding of their cold survival strategy is needed to predict and control their population in the future. In this study, metabolomics was performed to analyze the metabolic features of S. litura larvae exposed to two typical low temperatures: 15°C and 4°C, at which the development, locomotion and feeding activities are maintained or halted, respectively. The results showed that the strategies that regulate lipid and amino acid metabolism were similar at 15°C and 4°C. Cold exposure induced a metabolic shift of energy from carbohydrate to lipid and decreased free amino acids level. Biosynthesis likely contributed to the decrease in amino acids levels even at 4°C, a non-feeding temperature, suggesting an insufficient suppression of anabolism. This explains why food and high temperature pulses are necessary for their long-term cold survival. Glycometabolism was different between 15°C and 4°C. Carbohydrates were used rapidly at 15°C, while trehalose accumulated at 4°C. Interestingly, abundant trehalose and serine are prominent features of Spodoptera exigua larvae, an overwintering species, when compared to S. litura larvae. Exposure to 4°C also induced up-regulation of carbohydrase and protease in the guts of S. litura. Therefore, it is likely that concurrence of food supplement and fluctuating temperatures could facilitate the cold survival of S. litura larvae. We also found that exposure to 4°C could activate the mevalonate pathway in S. litura larvae, which might be related to glycometabolism at 4°C. Overall, our study describes

  11. Enhanced resistance to Spodoptera litura in endophyte infected cauliflower plants.

    PubMed

    Thakur, Abhinay; Kaur, Sanehdeep; Kaur, Amarjeet; Singh, Varinder

    2013-04-01

    Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.

  12. Susceptibility of Spodoptera exigua to 9 toxins from Bacillus thuringiensis.

    PubMed

    Hernández-Martínez, Patricia; Ferré, Juan; Escriche, Baltasar

    2008-03-01

    Nine of the most common lepidopteran active Cry proteins from Bacillus thuringiensis have been tested for activity against Spodoptera exigua. Because of possible intraspecific variability, three laboratory strains (FRA, HOL, and MUR) have been used. Mortality assays were performed with the three strains. LC(50) values for the active toxins were determined to the FRA and the HOL strains, whereas susceptibility of the MUR strain was assessed using only two concentrations. The results showed that Cry1Ca, Cry1Da, and Cry1Fa were the most effective toxins with all strains. Cry1Ab was found effective for the HOL strain, but very little effective against FRA (6.5-fold) and MUR strains. Cry1Aa and Cry1Ac were marginally toxic to all strains, whereas the rest of the toxins tested (Cry1Ba, Cry2Aa, and Cry2Ab) were non toxic. Significant differences in susceptibility among strains were also found for Cry1Da, being the FRA strain 25-fold more susceptible than the HOL strain. Growth inhibition, as an additional susceptibility parameter, was determined in the FRA strain with the 9 toxins. The toxicity profile obtained differed from that observed in mortality assays. Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ca, Cry1Da, and Cry1Fa toxins produced a similar larval growth inhibition. Cry2Aa had a lower but clear effect on larval growth inhibition, whereas Cry1Ba and Cry2Ab did not have any effect.

  13. Pupal melanization is associated with higher fitness in Spodoptera exigua

    PubMed Central

    Liu, Sisi; Wang, Mo; Li, Xianchun

    2015-01-01

    Melanism has long been thought to be a habitat adaptation with a fitness cost. Here we reported a homozygous melanic strain (SEM) of Spodoptera exigua (Hübner) (Insecta: Lepidoptera: Noctuidae) established with black pupae spontaneously occurring within a typical laboratory population (SEW). The melanization is expressed globally, and only in the pupal stage. After pupation, the melanic SEM pupae gradually accumulate melanin to become completely black within 6 hours, whereas the wild-type SEW pupae gradually turn yellow-brown. The melanic SEM strain exhibits faster development in all life stages, heavier pupa weight, more mating time, higher fecundity, and accordingly, higher net reproductive rate and population trend index. While no reproductive isolation was observed between the SEM and SEW strains, the mating times per female of the reciprocal crosses and the SEM intracrosses were significantly higher than those of the SEW intracrosses. This represents a rare case of melanization that has fitness gains, rather than costs. Analysis of the life-history traits of this case and 14 previously reported cases of insect melanism indicate that none of melanization origin, stage, space and variation type determining whether melanism will cause fitness gain or cost. PMID:26039886

  14. Helicoverpa zea (Lepidoptera: Noctuidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) Responses to Sorghum bicolor (Poales: Poaceae) Tissues From Lowered Lignin Lines

    PubMed Central

    Dowd, Patrick F.; Sattler, Scott E.

    2015-01-01

    The presence of lignin within biomass impedes the production of liquid fuels. Plants with altered lignin content and composition are more amenable to lignocellulosic conversion to ethanol and other biofuels but may be more susceptible to insect damage where lignin is an important resistance factor. However, reduced lignin lines of switchgrasses still retained insect resistance in prior studies. Therefore, we hypothesized that sorghum lines with lowered lignin content will also retain insect resistance. Sorghum excised leaves and stalk pith Sorghum bicolor (L.) Moench (Poales: Poaceae) from near isogenic brown midrib (bmr) 6 and 12 mutants lines, which have lowered lignin content and increased lignocellulosic ethanol conversion efficiency, were examined for insect resistance relative to wild-type (normal BTx623). Greenhouse and growth chamber grown plant tissues were fed to first-instar larvae of corn earworms, Helicoverpa zea (Boddie) and fall armyworms Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), two sorghum major pests. Younger bmr leaves had significantly greater feeding damage in some assays than wild-type leaves, but older bmr6 leaves generally had significantly less damage than wild-type leaves. Caterpillars feeding on the bmr6 leaves often weighed significantly less than those feeding on wild-type leaves, especially in the S. frugiperda assays. Larvae fed the pith from bmr stalks had significantly higher mortality compared with those larvae fed on wild-type pith, which suggested that bmr pith was more toxic. Thus, reducing lignin content or changing subunit composition of bioenergy grasses does not necessarily increase their susceptibility to insects and may result in increased resistance, which would contribute to sustainable production. PMID:25601946

  15. Susceptibility, mechanisms of response and resistance to Bacillus thuringiensis toxins in Spodoptera spp.

    PubMed

    Herrero, Salvador; Bel, Yolanda; Hernández-Martínez, Patricia; Ferré, Juan

    2016-06-01

    Bioinsecticides based on Bacillus thuringiensis have long been used as an alternative to synthetic insecticides to control insect pests. In this review, we focus on insects of the genus Spodoptera, including relevant polyphagous species that are primary and secondary pests of many crops, and how B. thuringiensis toxins can be used for Spodoptera spp. pest management. We summarize the main findings related to susceptibility, midgut binding specificity, mechanisms of response and resistance of this insect genus to B. thuringiensis toxins. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Evaluation of Antioxidant Activity and Growth Control Properties of Nonoscale Structure Produced from Aloe vera var. littoralis Extract on Clinical Isolates of Salmonella.

    PubMed

    Ranjbar, Reza; Arjomandzadegan, Mohammad; Hosseiny, Hossein

    2017-07-31

    The aim of the study was to examine antibacterial properties of microemulsion structure produced from Aloe vera var. littoralis extract as a new tool of nanoscale drug-like materials. Aloe vera var. littoralis (A. littoralis) extract was prepared by distillation method. A nonocarrier structure in the microemulsion system was prepared from the extract. Serial concentrations were prepared from 8 mg/mL extract and the nonocarrier containing 0.1 mg/mL pure extract and were evaluated by a disk diffusion method for 35 Salmonella clinical isolates. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by microbroth dilution assay using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method by an enzyme-linked immunosorbent assay(ELISA) Microplate Reader apparatus. Antioxidant activity of the extract was determined by measuring the ferric reducing ability of plasma (FRAP) assay. From 35 clinical isolates of Salmonella, 17 isolates-including resistant isolates of S.E.1103 and S.E.49-had a zone of inhibition (ZI) of 7 to 32 mm in 0.007 mg/mL of the extract. S.E.76 isolate exposed to 30 µg/mL ceftazidime disk had a ZI of 12 mm but had 10 mm in 7µg/mL of A. littoralis extract. The inhibitory effect of a nanocarrier at a concentration of 25 µg/mL by 20 mm ZI was comparable by the ceftazidime (30 µg/mL) effect. MIC50 was 0.25 mg/mL and MBC50 was 0.5 mg/mL by MTT method for the extract. It was shown that A.littoralis extract had antioxidant activity of 31.67 µM/mg that could be increased based on concentration. It was concluded that the nanocarrier had a significant effect on the studied isolates in comparison with ordinary antibiotics and had potential for use as a natural antioxidant and antimicrobial material in complementary medicine.

  17. Dynamics and regulation of glycolysis-tricarboxylic acid metabolism in the midgut of Spodoptera litura during metamorphosis.

    PubMed

    Hu, D; Luo, W; Fan, L F; Liu, F L; Gu, J; Deng, H M; Zhang, C; Huang, L H; Feng, Q L

    2016-04-01

    Significant changes usually take place in the internal metabolism of insects during metamorphosis. The glycolysis-tricarboxylic acid (glycolysis-TCA) pathway is important for energy metabolism. To elucidate its dynamics, the mRNA levels of genes involved in this pathway were examined in the midgut of Spodoptera litura during metamorphosis, and the pyruvate content was quantified. The expression patterns of these genes in response to starvation were examined, and the interaction between protein phosphatase 1 (PP1) and phosphofructokinase (PFK) was studied. The results revealed that the expression or activities of most glycolytic enzymes was down-regulated in prepupae and then recovered in some degree in pupae, and all TCA-related genes were remarkably suppressed in both the prepupae and pupae. Pyruvate was enriched in the pupal midgut. Taken together, these results suggest that insects decrease both glycolysis and TCA in prepupae to save energy and then up-regulate glycolysis but down-regulate TCA in pupae to increase the supply of intermediates for construction of new organs. The expression of all these genes were down-regulated by starvation, indicating that non-feeding during metamorphosis may be a regulator of glycolysis-TCA pathway in the midgut. Importantly, interaction between PP1 and PFK was identified and is suggested to be involved in the regulation of glycolysis. © 2015 The Royal Entomological Society.

  18. Identification of microRNAs by small RNA deep sequencing for synthetic microRNA mimics to control Spodoptera exigua.

    PubMed

    Zhang, Yu Liang; Huang, Qi Xing; Yin, Guo Hua; Lee, Samantha; Jia, Rui Zong; Liu, Zhi Xin; Yu, Nai Tong; Pennerman, Kayla K; Chen, Xin; Guo, An Ping

    2015-02-25

    Beet armyworm, Spodoptera exigua, is a major pest of cotton around the world. With the increase of resistance to Bacillus thuringiensis (Bt) toxin in transgenic cotton plants, there is a need to develop an alternative control approach that can be used in combination with Bt transgenic crops as part of resistance management strategies. MicroRNAs (miRNAs), a non-coding small RNA family (18-25 nt), play crucial roles in various biological processes and over-expression of miRNAs has been shown to interfere with the normal development of insects. In this study, we identified 127 conserved miRNAs in S. exigua by using small RNA deep sequencing technology. From this, we tested the effects of 11 miRNAs on larval development. We found three miRNAs, Sex-miR-10-1a, Sex-miR-4924, and Sex-miR-9, to be differentially expressed during larval stages of S. exigua. Oral feeding experiments using synthetic miRNA mimics of Sex-miR-10-1a, Sex-miR-4924, and Sex-miR-9 resulted in suppressed growth of S. exigua and mortality. Over-expression of Sex-miR-4924 caused a significant reduction in the expression level of chitinase 1 and caused abortive molting in the insects. Therefore, we demonstrated a novel approach of using miRNA mimics to control S. exigua development.

  19. Rhizobacteria activates (+)-δ-cadinene synthase genes and induces systemic resistance in cotton against beet armyworm (Spodoptera exigua).

    PubMed

    Zebelo, Simon; Song, Yuanyuan; Kloepper, Joseph W; Fadamiro, Henry

    2016-04-01

    Gossypol is an important allelochemical produced by the subepidermal glands of some cotton varieties and important for their ability to respond to changing biotic stress by exhibiting antibiosis against some cotton pests. Plant growth-promoting rhizobacteria (PGPR) are root-colonizing bacteria that increase plant growth and often elicit defence against plant pathogens and insect pests. Little is known about the effect of PGPR on cotton plant-insect interactions and the potential biochemical and molecular mechanisms by which PGPR enhance cotton plant defence. Here, we report that PGPR (Bacillus spp.) treated cotton plants showed significantly higher levels of gossypol compared with untreated plants. Similarly, the transcript levels of the genes (i.e. (+)-δ-cadinene synthase gene family) involved in the biosynthesis of gossypol were higher in PGPR-treated plants than in untreated plants. Furthermore, the levels of jasmonic acid, an octadecanoid-derived defence-related phytohormone and the transcript level of jasmonic acid responsive genes were higher in PGPR-treated plants than in untreated plants. Most intriguingly, Spodoptera exigua showed reduced larval feeding and development on PGPR-treated plants. These findings demonstrate that treatment of plants with rhizobacteria may induce significant biochemical and molecular changes with potential ramifications for plant-insect interactions. © 2015 John Wiley & Sons Ltd.

  20. Elevated atmospheric carbon dioxide concentration affects interactions between Spodoptera exigua (Lepidoptera: Noctuidae) larvae and two host plant species outdoors

    SciTech Connect

    Caulfield, F.; Bunce, J.A. )

    1994-08-01

    Beet armyworm, Spodoptera exigua (Huebner), larvae were placed on sugarbeet (Beta vulgaris L.) and pigweed (Amaranthus hybridus L.) plants in outdoor chambers in which the plants were growing at either the ambient ([approximately] 350 [mu]l liter[sup [minus]1]) or ambient plus 350 [mu]l liter[sup [minus]1] ([approximately] 700 [mu]l liter[sup [minus]1]) carbon dioxide concentration. A series of experiments was performed to determine if larvae reduced plant growth differently at the two carbon dioxide concentrations in either species and if the insect growth or survival differed with carbon dioxide concentration. Leaf nitrogen, water, starch, and soluble carbohydrate contents were measured to assess carbon dioxide concentration effects on leaf quality. Insect feeding significantly reduced plant growth in sugarbeet plants at 350 [mu]l liter[sup [minus]1] but not at 700 [mu]l liter[sup [minus]1] nor in pigweed at either carbon dioxide concentration. Larval survival was greater on sugarbeet plants at the elevated carbon dioxide concentration. Increased survival occurred only if the insects were at the elevated carbon dioxide concentration and consumed leaf material grown at the elevated concentration. Leaf quality was only marginally affected by growth at elevated carbon dioxide concentration in these experiments. The results indicate that in designing experiments to predict effects of elevated atmospheric carbon dioxide concentrations on plant-insect interactions, both plants and insects should be exposed to the experimental carbon dioxide concentrations, as well as to as realistic environmental conditions as possible.

  1. Susceptibility and aversion of Spodoptera frugiperda (Lepidoptera: Noctuidae) to Cry1F Bt maize and considerations for insect resistance management.

    PubMed

    Binning, Rachel R; Coats, Joel; Kong, Xiaoxiao; Hellmich, Richard L

    2014-02-01

    Bacillus thuringiensis (Bt) maize was developed primarily for North American pests such as European corn borer (Ostrinia nubilalis (Hübner)). However, most Bt maize products are also cultivated outside of North America, where the primary pests may be different and may have lower susceptibility to Bt toxins. Fall armyworm (Spodoptera frugiperda JE Smith) is an important pest and primary target of Bt maize in Central and South America. S. frugiperda susceptibility to Cry1F (expressed in event TC1507) is an example of a pest-by-toxin interaction that does not meet the high-dose definition. In this study, the behavioral and toxic response of S. frugiperda to Cry1F maize was investigated by measuring the percentage of time naive third instars spent feeding during a 3-min exposure. S. frugiperda also were exposed as third instars to Cry1F maize for 14 d to measure weight gain and survival. S. frugiperda demonstrated an initial, postingestive aversive response to Cry1F maize, and few larvae survived the 14 d exposure. The role of susceptibility and avoidance are discussed in the context of global IRM refuge strategy development for Bt products.

  2. Quantitative relationships between induced jasmonic acid levels and volatile emission in Zea mays during Spodoptera exigua herbivory.

    PubMed

    Schmelz, Eric A; Alborn, Hans T; Banchio, Erika; Tumlinson, James H

    2003-02-01

    Jasmonic acid (JA) has long been hypothesized to be an important regulator of insect-induced volatile emission; however, current models are based primarily on circumstantial evidence derived from pharmacological studies. Using beet armyworm caterpillars (BAW: Spodoptera exigua) and intact corn seedlings, we examine this hypothesis by measuring both the time-course of insect-induced JA levels and the relationships between endogenous JA levels, ethylene, indole and sesquiterpenes. In separate Morning and Evening time-course trials, BAW feeding stimulated increases in JA levels within the first 4-6 h and resulted in maximal increases in JA, indole, sesquiterpenes and ethylene 8-16 h later. During BAW herbivory, increases in JA either paralleled or preceded the increases in indole, sesquiterpenes and ethylene in the Morning and Evening trials, respectively. By varying the intensity of the BAW herbivory, we demonstrate that strong positive relationships exist between the resulting variation in insect-induced JA levels and volatile emissions such as indole and the sesquiterpenes. To address potential signaling interactions between herbivore-induced JA and ethylene, plants were pretreated with 1-methylcyclopropene (1-MCP), an inhibitor of ethylene perception. 1-MCP pretreatment resulted in reduced production of ethylene and volatile emission following BAW herbivory but did not alter the insect-induced accumulation of JA. Our results strongly support a role for JA in the regulation of insect-induced volatile emission but also suggest that ethylene perception regulates the magnitude of volatile emission during herbivory.

  3. Bioactive Terpenoids and Flavonoids from Daucus littoralis Smith subsp. hyrcanicus Rech.f, an Endemic Species of Iran

    PubMed Central

    2014-01-01

    Background Daucus littoralis Smith subsp. hyrcanicus Rech.f. (Apiaceae) is an endemic species in northern parts of Iran where it is commonly named Caspian carrot. The fruits have been used as condiment. Methods In a series of in vitro assays, antioxidant (DPPH and FRAP assays), cytotoxic and antimicrobial activities of different extracts of roots and fruits were evaluated for the first time. The separation and purification of the compounds were carried out on the most potent extracts using various chromatographic methods and identified by spectroscopic data (1H and 13C NMR). Results The results showed that among the extracts only fruit methanol extract (FME) has significant antioxidant activity (IC50 = 145.93 μg.ml-1 in DPPH assay and 358 ± 0.02 mmol FeII/g dry extract in FRAP assay). The radical scavenging activity of FME at 400 μg.ml-1 was comparable with α-tocopherol (40 μg.ml-1) and with BHA (100 μg.ml-1) (p > 0.05). FME did not show any toxicity against cancerous and normal cell lines. Fruit ethyl acetate extract (FEE) had cytotoxic activity against breast carcinoma and hepatocellular carcinoma cells (IC50 168.4 and 185 μg.ml-1, respectively), while it did not possess antioxidant activity in comparison with α-tocopherol and BHA as standard compounds. Ethyl acetate and methanol extract of fruits showed antimicrobial activity against Staphylococcus aureus (MIC: 3.75 mg.ml-1) and Candida albicans (MIC: 15.6 and 7.8 mg.ml-1, respectively). Four terpenoids were isolated form FEE including: β-sitosterol (1), stigmasterol (2), caryophyllene oxide (3), β-amyrin (4). Also, three flavonoids namely quercetin 3-O-β-glucoside (5), quercetin 3-O-β-galactoside (6) and luteolin (7) were isolated from FME. Conclusion This study showed that FEE and FME of D. littoralis Smith subsp. hyrcanicus Rech.f. had the highest biological activities which may be correlated with in vitro cytotoxic, antimicrobial and antioxidant activities of terpenoids and

  4. Insights into the physiological responses of the facultative halophyte Aeluropus littoralis to the combined effects of salinity and phosphorus availability.

    PubMed

    Talbi Zribi, Ons; Barhoumi, Zouhaier; Kouas, Saber; Ghandour, Mohamed; Slama, Ines; Abdelly, Chedly

    2015-09-15

    In this work, we investigate the physiological responses to P deficiency (5μM KH2PO4=D), salt stress (400mM NaCl=C+S), and their combination (D+S) on the facultative halophyte Aeluropus littoralis to understand how plants adapt to these combined stresses. When individually applied, both P deficiency and salinity significantly restricted whole plant growth, with a more marked effect of the latter stress. However, the effects of the two stresses were not additive in plant biomass production since the response of plants to combined salinity and P deficiency was similar to that of plants grown under salt stress alone. In addition the observed features under salinity alone are kept when plants are simultaneously subjected to the combined effects of salinity and P deficiency such as biomass partitioning; the synthesis of proline and the K(+)/Na(+) selectivity ratio. Thus, increasing P availability under saline conditions has no significant effect on salt tolerance in this species. Plants cultivated under the combined effects of salinity and P deficiency exhibited the lowest leaf water potential. This trend was associated with a high accumulation of Na(+), Cl(-) and proline in shoots of salt treated plants suggesting the involvement of these solutes in osmotic adjustment. Proline could be involved in other physiological processes such as free radical scavenging. Furthermore, salinity has no significant effect on phosphorus acquisition when combined with a low P supply and it significantly decreased this parameter when combined with a sufficient P supply. This fact was probably due to salt's effect on P transporters. In addition, shoot soluble sugars accumulation under both P deficiency treatments with and without salt likely play an important role in the adaptation of A. littoralis plants to P shortage applied alone or combined with salinity. Moreover, there was a strong correlation between shoot and root intracellular acid phosphatase activity and phosphorus use

  5. Feeding Tubes

    MedlinePlus

    ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ...

  6. Laboratory and field evaluations for efficacy of a fast-killing baculovirus isolate from Spodoptera frugiperda

    USDA-ARS?s Scientific Manuscript database

    Three biopesticide parameters were evaluated for a fast-killing isolate (3AP2) Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) and a wild-type isolate (Sf3) of the same baculovirus. Both isolates were evaluated for virus production using in vivo methods, for speed of kill based on bioas...

  7. Monitoring two native Spodoptera species using an exotic pheromone lure developed for an exotic species

    USDA-ARS?s Scientific Manuscript database

    The pheromone lure for the exotic species Spodoptera exempta was successful at attracting two native species, S. latifascia and S. albula. Trapping was conducted in north-central Florida and in southern Texas. Large numbers of both native species were collected throughout the season....

  8. Active role of fatty acid amino acid conjugates in nitrogen metabolidm by Spodoptera litura larvae

    USDA-ARS?s Scientific Manuscript database

    Since the first fatty acid amino acid conjugate (FAC) was isolated from regurgitant of Spodoptera exigua larvae in 1997 [volicitin: N-(17-hydroxylinolenoyl)- L-glutamine], their role as elicitors of induced responses in plants has been well documented. However, studies of the biosyntheses as well as...

  9. Genetic and biological variation among nucleopolyhedrovirus isolates from spodoptera frugiperda (lepidotpera: noctuidae)

    USDA-ARS?s Scientific Manuscript database

    A PCR-based method was used to identify and distinguish among 40 uncharacterized nucleopolyhedrovirus (NPV) isolates from the moth Spodoptera frugiperda that were part of an insect virus collection. Phylogenetic analysis was carried out with sequences amplified from two strongly conserved loci (pol...

  10. Whole-Genome Sequence of the Spodoptera frugiperda Sf9 Insect Cell Line

    PubMed Central

    Nandakumar, Subhiksha; Ma, Hailun

    2017-01-01

    ABSTRACT The draft whole-genome sequence of the Spodoptera frugiperda Sf9 insect cell line was obtained using long-read PacBio sequence technology and Canu assembly. The final assembled genome consisted of 451 Mbp in 4,577 contigs, with 12,716× mean coverage and a G+C content of 36.53%. PMID:28839023

  11. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants.

    PubMed

    Gordy, John W; Leonard, B Rogers; Blouin, David; Davis, Jeffrey A; Stout, Michael J

    2015-01-01

    Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

  12. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants

    PubMed Central

    Gordy, John W.; Leonard, B. Rogers; Blouin, David; Davis, Jeffrey A.; Stout, Michael J.

    2015-01-01

    Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved. PMID:26332833

  13. Ear Mite Removal in the Santa Catalina Island Fox (Urocyon littoralis catalinae): Controlling Risk Factors for Cancer Development.

    PubMed

    Moriarty, Megan E; Vickers, T Winston; Clifford, Deana L; Garcelon, David K; Gaffney, Patricia M; Lee, Kenneth W; King, Julie L; Duncan, Calvin L; Boyce, Walter M

    2015-01-01

    Ear mites (Otodectes cynotis) and ear canal tumors are highly prevalent among federally endangered Island foxes (Urocyon littoralis catalinae) living on Santa Catalina Island off the coast of Southern California. Since studies began in the 1990s, nearly all foxes examined were found to be infected with ear mites, and ceruminous gland tumors (carcinomas and adenomas) were detected in approximately half of all foxes ≥ 4 years of age. We hypothesized that reduction of ear mite infection would reduce otitis externa and ceruminous gland hyperplasia, a risk factor for tumor development. In this study, we conducted a randomized field trial to assess the impact of acaricide treatment on ear mite prevalence and intensity of infection, otitis externa, ceruminous gland hyperplasia, and mite-specific IgG and IgE antibody levels. Treatment was highly effective at eliminating mites and reducing otitis externa and ceruminous gland hyperplasia, and mite-specific IgG antibody levels were significantly lower among uninfected foxes. Ceruminous gland hyperplasia increased in the chronically infected, untreated foxes during the six month study. Our results provide compelling evidence that acaricide treatment is an effective means of reducing ear mites, and that mite removal in turn reduces ear lesions and mite-specific IgG antibody levels in Santa Catalina Island foxes. This study has advanced our understanding of the underlying pathogenesis which results in ceruminous gland tumors, and has helped inform management decisions that impact species conservation.

  14. A suspected canine distemper epidemic as the cause of a catastrophic decline in Santa Catalina Island foxes (Urocyon littoralis catalinae).

    PubMed

    Timm, Steven F; Munson, Linda; Summers, Brian A; Terio, Karen A; Dubovi, Edward J; Rupprecht, Charles E; Kapil, Sanjay; Garcelon, David K

    2009-04-01

    The island fox (Urocyon littoralis catalinae) population on Santa Catalina Island, California, USA declined precipitously in 1999 with an approximate 95% reduction on their eastern range, an area representing 87% of the island. During this investigation, between October 1999 and April 2000, evidence of live foxes dramatically decreased. The only carcass recovered during the decline succumbed to a co-infection of canine distemper virus (CDV) and toxoplasmosis. Sequence analysis of the viral P gene, derived by polymerase chain reaction, indicated that the virus was closely related to CDV from a mainland USA raccoon (Procyon lotor). Nine of 10 foxes trapped in 1999-2000, on the eastern portion of the island after the decline, had serologic evidence of exposure to CDV, whereas only four of 19 foxes trapped in this region in 1998 had antibodies reactive against CDV. The confirmation of CDV in one deceased fox, evidence of exposure to CDV in east-end foxes in 1999-2000 compared to 1998, and documentation of raccoon introductions to the island, implicates canine distemper as the cause of the population decline.

  15. Ear Mite Removal in the Santa Catalina Island Fox (Urocyon littoralis catalinae): Controlling Risk Factors for Cancer Development

    PubMed Central

    Moriarty, Megan E.; Vickers, T. Winston; Clifford, Deana L.; Garcelon, David K.; Gaffney, Patricia M.; Lee, Kenneth W.; King, Julie L.; Duncan, Calvin L.; Boyce, Walter M.

    2015-01-01

    Ear mites (Otodectes cynotis) and ear canal tumors are highly prevalent among federally endangered Island foxes (Urocyon littoralis catalinae) living on Santa Catalina Island off the coast of Southern California. Since studies began in the 1990s, nearly all foxes examined were found to be infected with ear mites, and ceruminous gland tumors (carcinomas and adenomas) were detected in approximately half of all foxes ≥ 4 years of age. We hypothesized that reduction of ear mite infection would reduce otitis externa and ceruminous gland hyperplasia, a risk factor for tumor development. In this study, we conducted a randomized field trial to assess the impact of acaricide treatment on ear mite prevalence and intensity of infection, otitis externa, ceruminous gland hyperplasia, and mite-specific IgG and IgE antibody levels. Treatment was highly effective at eliminating mites and reducing otitis externa and ceruminous gland hyperplasia, and mite-specific IgG antibody levels were significantly lower among uninfected foxes. Ceruminous gland hyperplasia increased in the chronically infected, untreated foxes during the six month study. Our results provide compelling evidence that acaricide treatment is an effective means of reducing ear mites, and that mite removal in turn reduces ear lesions and mite-specific IgG antibody levels in Santa Catalina Island foxes. This study has advanced our understanding of the underlying pathogenesis which results in ceruminous gland tumors, and has helped inform management decisions that impact species conservation. PMID:26641820

  16. Induced changes in island fox (Urocyon littoralis) activity do not mitigate the extinction threat posed by a novel predator.

    PubMed

    Hudgens, Brian R; Garcelon, David K

    2011-03-01

    Prey response to novel predators influences the impacts on prey populations of introduced predators, bio-control efforts, and predator range expansion. Predicting the impacts of novel predators on native prey requires an understanding of both predator avoidance strategies and their potential to reduce predation risk. We examine the response of island foxes (Urocyon littoralis) to invasion by golden eagles (Aquila chrysaetos). Foxes reduced daytime activity and increased night time activity relative to eagle-naïve foxes. Individual foxes reverted toward diurnal tendencies following eagle removal efforts. We quantified the potential population impact of reduced diurnality by modeling island fox population dynamics. Our model predicted an annual population decline similar to what was observed following golden eagle invasion and predicted that the observed 11% reduction in daytime activity would not reduce predation risk sufficiently to reduce extinction risk. The limited effect of this behaviorally plastic predator avoidance strategy highlights the importance of linking behavioral change to population dynamics for predicting the impact of novel predators on resident prey populations.

  17. PGE2 induces oenocytoid cell lysis via a G protein-coupled receptor in the beet armyworm, Spodoptera exigua

    USDA-ARS?s Scientific Manuscript database

    Eicosanoids mediate cellular and humoral immune responses in the beet armyworm, Spodoptera exigua, including activation of prophenoloxidase (PPO). PPO activation begins with release of its inactive zymogen, PPO, from oenocytoids in response to prostaglandins (PGs). Based on the biomedical literatur...

  18. Using Small-Scale Studies to Prioritize Threats and Guide Recovery of a Rare Hemiparasitic Plant: Cordylanthus rigidus ssp. littoralis

    PubMed Central

    Watts, Sean M.; Uhl, Melissa M.; Maurano, Stephen P.; Nuccio, Erin E.

    2010-01-01

    Background Recovering endangered species would benefit from identifying and ranking of the factors that threaten them. Simply managing for multiple positive influences will often aid in recovery; however, the relative impacts of multiple threats and/or interactions among them are not always predictable. We used a series of experiments and quantitative observational studies to examine the importance of five potential limiting factors to the abundance of a state-listed endangered hemiparasitic annual forb, Cordylanthus rigidus ssp. littoralis (C.r.l., California, USA): host availability, mammalian herbivores, insect seed predators, fire suppression, and exotic species. While this initial assessment is certainly not a complete list, these factors stem from direct observation and can inform provisional recommendations for management and further research. Methodology and Principal Findings Studies were conducted at five sites and included assessments of the influence of host availability, exotic species, exclusion of mammalian herbivores and insect seed predators on C.r.l. productivity, and simulated effects of fire on seed germination. C.r.l. was limited by multiple threats: individuals with access to host species produced up to three times more inflorescences than those lacking hosts, mammalian herbivory reduced C.r.l. size and fecundity by more than 50% and moth larvae reduced seed production by up to 40%. Litter deposition and competition from exotic plant species also appears to work in conjunction with other factors to limit C.r.l. throughout its life cycle. Conclusions and Significance The work reported here highlights the contribution that a series of small-scale studies can make to conservation and restoration. Taken as a whole, the results can be used immediately to inform current management and species recovery strategies. Recovery of C.r.l. will require management that addresses competition with exotic plant species, herbivore pressure, and availability of

  19. Using small-scale studies to prioritize threats and guide recovery of a rare hemiparasitic plant: Cordylanthus rigidus ssp. littoralis.

    PubMed

    Watts, Sean M; Uhl, Melissa M; Maurano, Stephen P; Nuccio, Erin E

    2010-01-26

    Recovering endangered species would benefit from identifying and ranking of the factors that threaten them. Simply managing for multiple positive influences will often aid in recovery; however, the relative impacts of multiple threats and/or interactions among them are not always predictable. We used a series of experiments and quantitative observational studies to examine the importance of five potential limiting factors to the abundance of a state-listed endangered hemiparasitic annual forb, Cordylanthus rigidus ssp. littoralis (C.r.l., California, USA): host availability, mammalian herbivores, insect seed predators, fire suppression, and exotic species. While this initial assessment is certainly not a complete list, these factors stem from direct observation and can inform provisional recommendations for management and further research. Studies were conducted at five sites and included assessments of the influence of host availability, exotic species, exclusion of mammalian herbivores and insect seed predators on C.r.l. productivity, and simulated effects of fire on seed germination. C.r.l. was limited by multiple threats: individuals with access to host species produced up to three times more inflorescences than those lacking hosts, mammalian herbivory reduced C.r.l. size and fecundity by more than 50% and moth larvae reduced seed production by up to 40%. Litter deposition and competition from exotic plant species also appears to work in conjunction with other factors to limit C.r.l. throughout its life cycle. The work reported here highlights the contribution that a series of small-scale studies can make to conservation and restoration. Taken as a whole, the results can be used immediately to inform current management and species recovery strategies. Recovery of C.r.l. will require management that addresses competition with exotic plant species, herbivore pressure, and availability of preferred host species.

  20. Expression of the Aeluropus littoralis AlSAP Gene Enhances Rice Yield under Field Drought at the Reproductive Stage.

    PubMed

    Ghneim-Herrera, Thaura; Selvaraj, Michael G; Meynard, Donaldo; Fabre, Denis; Peña, Alexandra; Ben Romdhane, Walid; Ben Saad, Rania; Ogawa, Satoshi; Rebolledo, Maria C; Ishitani, Manabu; Tohme, Joe; Al-Doss, Abdullah; Guiderdoni, Emmanuel; Hassairi, Afif

    2017-01-01

    We evaluated the yields of Oryza sativa L. 'Nipponbare' rice lines expressing a gene encoding an A20/AN1 domain stress-associated protein, AlSAP, from the halophyte grass Aeluropus littoralis under the control of different promoters. Three independent field trials were conducted, with drought imposed at the reproductive stage. In all trials, the two transgenic lines, RN5 and RN6, consistently out-performed non-transgenic (NT) and wild-type (WT) controls, providing 50-90% increases in grain yield (GY). Enhancement of tillering and panicle fertility contributed to this improved GY under drought. In contrast with physiological records collected during previous greenhouse dry-down experiments, where drought was imposed at the early tillering stage, we did not observe significant differences in photosynthetic parameters, leaf water potential, or accumulation of antioxidants in flag leaves of AlSAP-lines subjected to drought at flowering. However, AlSAP expression alleviated leaf rolling and leaf drying induced by drought, resulting in increased accumulation of green biomass. Therefore, the observed enhanced performance of the AlSAP-lines subjected to drought at the reproductive stage can be tentatively ascribed to a primed status of the transgenic plants, resulting from a higher accumulation of biomass during vegetative growth, allowing reserve remobilization and maintenance of productive tillering and grain filling. Under irrigated conditions, the overall performance of AlSAP-lines was comparable with, or even significantly better than, the NT and WT controls. Thus, AlSAP expression inflicted no penalty on rice yields under optimal growth conditions. Our results support the use of AlSAP transgenics to reduce rice GY losses under drought conditions.

  1. Expression of the Aeluropus littoralis AlSAP Gene Enhances Rice Yield under Field Drought at the Reproductive Stage

    PubMed Central

    Ghneim-Herrera, Thaura; Selvaraj, Michael G.; Meynard, Donaldo; Fabre, Denis; Peña, Alexandra; Ben Romdhane, Walid; Ben Saad, Rania; Ogawa, Satoshi; Rebolledo, Maria C.; Ishitani, Manabu; Tohme, Joe; Al-Doss, Abdullah; Guiderdoni, Emmanuel; Hassairi, Afif

    2017-01-01

    We evaluated the yields of Oryza sativa L. ‘Nipponbare’ rice lines expressing a gene encoding an A20/AN1 domain stress-associated protein, AlSAP, from the halophyte grass Aeluropus littoralis under the control of different promoters. Three independent field trials were conducted, with drought imposed at the reproductive stage. In all trials, the two transgenic lines, RN5 and RN6, consistently out-performed non-transgenic (NT) and wild-type (WT) controls, providing 50–90% increases in grain yield (GY). Enhancement of tillering and panicle fertility contributed to this improved GY under drought. In contrast with physiological records collected during previous greenhouse dry-down experiments, where drought was imposed at the early tillering stage, we did not observe significant differences in photosynthetic parameters, leaf water potential, or accumulation of antioxidants in flag leaves of AlSAP-lines subjected to drought at flowering. However, AlSAP expression alleviated leaf rolling and leaf drying induced by drought, resulting in increased accumulation of green biomass. Therefore, the observed enhanced performance of the AlSAP-lines subjected to drought at the reproductive stage can be tentatively ascribed to a primed status of the transgenic plants, resulting from a higher accumulation of biomass during vegetative growth, allowing reserve remobilization and maintenance of productive tillering and grain filling. Under irrigated conditions, the overall performance of AlSAP-lines was comparable with, or even significantly better than, the NT and WT controls. Thus, AlSAP expression inflicted no penalty on rice yields under optimal growth conditions. Our results support the use of AlSAP transgenics to reduce rice GY losses under drought conditions. PMID:28659945

  2. Proteolytic processing of Bacillus thuringiensis Vip3A proteins by two Spodoptera species.

    PubMed

    Caccia, Silvia; Chakroun, Maissa; Vinokurov, Konstantin; Ferré, Juan

    2014-08-01

    Vip3 proteins have been described to be secreted by Bacillus thuringiensis during the vegetative growth phase and to display a broad insecticidal spectrum against lepidopteran larvae. Vip3Aa protoxin has been reported to be significantly more toxic to Spodoptera frugiperda than to Spodoptera exigua and differences in the midgut processing have been proposed to be responsible. In contrast, we have found that Vip3Ae is essentially equally toxic against these two species. Proteolysis experiments were performed to study the stability of Vip3A proteins to peptidase digestion and to see whether the differences found could explain differences in toxicity against these two Spodoptera species. It was found that activation of the protoxin form and degradation of the 62kDa band took place at lower concentrations of trypsin when using Vip3Aa than when using Vip3Ae. The opposite effect was observed for chymotrypsin. Vip3Aa and Vip3Ae protoxins were effectively processed by midgut content extracts from the two Spodoptera species and the proteolytic activation did not produce a peptidase resistant core under these in vitro conditions. Digestion experiments performed with S. frugiperda chromatography-purified digestive serine peptidases showed that the degradation of the Vip3A toxins active core is mainly due to the action of cationic chymotrypsin-like peptidase. Although the digestion patterns of Vip3A proteins do not always correlate with toxicity, the peptidase stability of the 62kDa core is in agreement with intraspecific differences of toxicity of the Vip3Aa protein.

  3. Biological activity of astilbin from Dimorphandra mollis against Anticarsia gemmatalis and Spodoptera frugiperda.

    PubMed

    Batista Pereira, Luciane G; Petacci, Fernando; Fernandes, João B; Corrêa, Arlene G; Vieira, Paulo C; da Silva, M Fátima G F; Malaspina, Osmar

    2002-05-01

    Astilbin was isolated in high yield from Dimorphandra mollis, and its insecticidal and growth inhibiting activity by stomach ingestion were evaluated against Anticarsia gemmatalis and Spodoptera frugiperda. The insecticidal activity of astilbin, the weight reduction of the larval phase and the prolongation of the larval and pupal phases were verified for both species. Astilbin was identified on the base of its NMR, MS and physical data.

  4. Induction of resistance of corn plants to Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) by application of silicon and gibberellic acid.

    PubMed

    Alvarenga, R; Moraes, J C; Auad, A M; Coelho, M; Nascimento, A M

    2017-08-01

    The aim of this study was to evaluate the effects of silicon application and administration of the phytohormone gibberellic acid on resistance of the corn plants to the fall armyworm (FAW), Spodoptera frugiperda, and their vegetative characteristics. We evaluated larval and pupal duration, survival and biomass, and adult longevity, malformation and fecundity of S. frugiperda after feeding on plant matter treated with silicon and/or gibberellic acid. The feeding preference of FAW first-instar larvae, the total leaf area consumed by the insects, and the vegetative parameters of corn plants were also evaluated. No significant differences were observed in the measured parameters of larval and pupal stages of S. frugiperda in response to silicon or gibberellic acid. In adult stage insects, the number of eggs per female was significantly reduced in insects derived from larvae fed plants treated with silicon or gibberellic acid. In a non-preference test, 48 h after release, caterpillars preferred control untreated plants and consumed less matter from plants that had received hormonal treatment (gibberellic acid). Gibberellic acid also altered the vegetative characteristics of plants, by increasing their height, shoot fresh and dry mass, and silicon content. We conclude that gibberellic acid can alter the vegetative characteristics and silicon uptake of corn plants, leading to a reduction in their consumption by S. frugiperda larvae and a decrease in female insect oviposition.

  5. Sources of fall armyworm,Spodoptera frugiperda (Lepidoptera: Noctuidae), kairomones eliciting host-finding behavior inCotesia (=Apanteles) marginivenitris (Hymenoptera: Braconidae).

    PubMed

    Loke, W H; Ashley, T R

    1984-07-01

    Bioassay responses inCotesia marginiventris (Cresson) females to materials derived from fall armyworm (FAW) larvae,Spodoptera frugiperda (J. E. Smith), were most intense for frass and somewhat less intense for larval and pupal cutical materials, scales, exuviae, silk, and oral secretion, with FAW larval hemolymph eliciting only a slight response. The highest percentage of ovipositor probing was caused by frass (100%) and moth scales (90%). Various types of corn-leaf damage when assayed alone did not produce responses as intense as when assayed in combination with frass, cuticle material, and oral secretion. Parasitoid response was somewhat better to frass derived from FAW larvae feeding on corn and peanut leaves than from larvae feeding on the foliage of soybeans, Bermuda grass, cowpeas, or laboratory diet. Hexane and chloroform were better than methanol and water for extracting active material from FAW frass, and chloroform was the best of these solvents for extracting corn leaves. Serial dilutions of frass extracts resulted in a reduction in parasitoid response.

  6. The use of silica-immobilized brown alga (Pilayella littoralis) for metal preconcentration and determination by inductively coupled plasma optical emission spectrometry.

    PubMed

    Carrilho, Elma Neide V M; Nóbrega, Joaquim A; Gilbert, Thomas R

    2003-08-29

    The brown alga Pilayella littoralis was used as a new biosorbent in an on-line metal preconcentration procedure in a flow-injection system. Al, Co, Cu and Fe were determined in lake water samples by inductively coupled plasma optical emission spectrometry (ICP-OES) after preconcentration in a silica-immobilized alga column. Like other algae, P. littoralis exhibited strong affinity for these metals proving to be an effective accumulation medium. Metals were bound at pH 5.5 and were displaced at pH<2 with diluted HCl. The enrichment factors for Cu(II), Fe(III), Al(III) and Co(II) were 13, 7, 16 and 11, respectively. Metal sorption efficiency ranged from 86 to 90%. The method accuracy was assessed by using drinking water certified reference material and graphite furnace atomic absorption spectrometry (GFAAS) as a comparison technique. The column procedure allowed a less time consuming, easy regeneration of the biomaterial and rigidity of the alga provided by its immobilization on silica gel.

  7. Effects of nickel exposure on testicular function, oxidative stress, and male reproductive dysfunction in Spodoptera litura Fabricius.

    PubMed

    Sun, Hongxia; Wu, Wenjing; Guo, Jixing; Xiao, Rong; Jiang, Fengze; Zheng, Lingyan; Zhang, Guren

    2016-04-01

    Nickel is an environmental pollutant that adversely affects the male reproductive system. In the present study, the effects of nickel exposure on Spodoptera litura Fabricius were investigated by feeding larvae artificial diets containing different doses of nickel for three generations. Damage to testes and effects on male reproduction were examined. The amount of nickel that accumulated in the testes of newly emerged males increased as the nickel dose in the diet increased during a single generation. Nickel exposure increased the amount of thiobarbituric acid reactive substances and decreased the amount of glutathione in treatment groups compared with the control. The activity levels of the antioxidant response indices superoxide dismutases, catalase, and glutathione peroxidase in the testes showed variable dose-dependent relationships with nickel doses and duration of exposure. Nickel doses also disrupted the development of the testes by decreasing the weight and volume of testes and the number of eupyrene and apyrene sperm bundles in treatment groups compared with the control. When the nickel-treated males mated with normal females, fecundity was inhibited by the higher nickel doses in all three generations, but fecundity significantly increased during the second generation, which received 5 mg kg(-1) nickel. Hatching rates in all treatments significantly decreased in a dose-dependent manner in the three successive generations. The effects of nickel on these parameters correlated with the duration of nickel exposure. Results indicate assays of testes may be a novel and efficient means of evaluating the effects of heavy metals on phytophagous insects in an agricultural environment.

  8. Enteral feedings.

    PubMed

    Chernoff, R

    1980-01-01

    The benefits, equipment used, commercially available sources, and the indications and techniques for administration of enteral nutrients are reviewed. In many malabsorption states, enteral feeding is preferable and parenteral nutrients are seldom indicated. Transitional enteral nutrient support usually is indicated after parenteral nutrient therapy. Enteral tube-feeding formulas should be matched to the patient's needs; formulas using blenderized natural foods or intact isolated nutrients are appropriate for patients with intact gastrointestinal tracts. Patients should be monitored for glucosuria and hyperglycemia, bloating, nausea, dehydration, and renal, hepatic and hematologic status. Formula dilution, and a reduced flow rate or use of continuous-drip feeding, will reduce the incidence of osmotic diarrhea. The effectiveness, low cost and low potential for serious complications make enteral feeding preferable to parenteral nutrient therapy for many patients.

  9. Breast-Feeding Twins: Making Feedings Manageable

    MedlinePlus

    ... breast-feed more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring an adequate milk supply to combining breast-feeding and formula-feeding. By Mayo Clinic Staff If ...

  10. Biliatresone, a Reactive Natural Toxin from Dysphania glomulifera and D. littoralis: Discovery of the Toxic Moiety 1,2-Diaryl-2-Propenone.

    PubMed

    Koo, Kyung A; Lorent, Kristin; Gong, Weilong; Windsor, Peter; Whittaker, Stephen J; Pack, Michael; Wells, Rebecca G; Porter, John R

    2015-08-17

    We identified a reactive natural toxin, biliatresone, from Dysphania glomulifera and D. littoralis collected in Australia that produces extrahepatic biliary atresia in a zebrafish model. Three additional isoflavonoids, including the known isoflavone betavulgarin, were also isolated. Biliatresone is in the very rare 1,2-diaryl-2-propenone class of isoflavonoids. The α-methylene of the 1,2-diaryl-2-propenone of biliatresone spontaneously reacts via Michael addition in the formation of water and methanol adducts. The lethal dose of biliatresone in a zebrafish assay was 1 μg/mL, while the lethal dose of synthetic 1,2-diaryl-2-propen-1-one was 5 μg/mL, suggesting 1,2-diaryl-2-propenone as the toxic Michael acceptor.

  11. Biliatresone, a Reactive Natural Toxin from Dysphania glomulifera and D. littoralis: Discovery of the Toxic Moiety 1,2-Diaryl-2-Propenone

    PubMed Central

    Koo, Kyung A.; Lorent, Kristin; Gong, Weilong; Windsor, Peter; Whittaker, Stephen J.; Pack, Michael; Wells, Rebecca G.; Porter, John R.

    2016-01-01

    We identified a reactive natural toxin, biliatresone, from Dysphania glomulifera and D. littoralis collected in Australia that produces extrahepatic biliary atresia in a zebrafish model. Three additional isoflavonoids, including the known isoflavone betavulgarin, were also isolated. Biliatresone is in the very rare 1,2-diaryl-2-propenone class of isoflavonoids. The α-methylene of the 1,2-diaryl-2-propenone of biliatresone spontaneously reacts via Michael addition in the formation of water and methanol adducts. The lethal dose of biliatresone in a zebrafish assay was 1 μg/mL, while the lethal dose of synthetic 1,2-diaryl-2-propen-1-one was 5 μg/mL, suggesting 1,2-diaryl-2-propenone as the toxic Michael acceptor. PMID:26175131

  12. Angiocaulus gubernaculatus in the island fox (Urocyon littoralis) from the California Channel Islands and comments on the diagnosis of angiostrongylidae nematodes in canid and mustelid hosts.

    PubMed

    Faulkner, C T; Patton, S; Munson, L; Johnsont, E M; Coonan, T J

    2001-10-01

    Adult nematode parasites were recovered from the heart blood of a deceased island fox (Urocyon littoralis) submitted for necropsy to determine the cause of death. Examination of the recovered nematodes supported the generic diagnosis of Angiocaulus, a parasite in Angiostrongylidae found in domestic and wild canids and mustelids. Specific diagnosis of the worms from the island fox as Angiocaulus gubernaculatus is based on the morphology of the dorsal ray in the copulatory bursa of the male worm and its comparison with published descriptions of Angiocaulus raillieti and A. gubernaculatus. Although A. gubernaculatus has been typically associated with mustelid hosts, its occurrence in the island fox indicates that the host distribution for the parasite may not be as restricted as previously believed.

  13. Tube Feedings.

    ERIC Educational Resources Information Center

    Plummer, Nancy

    This module on tube feedings is intended for use in inservice or continuing education programs for persons who work in long-term care. Instructor information, including teaching suggestions and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then provided. A brief discussion follows…

  14. Breast Feeding.

    ERIC Educational Resources Information Center

    International Children's Centre, Paris (France).

    This set of documents consists of English, French, and Spanish translations of four pamphlets on breast-feeding. The pamphlets provide information designed for lay persons, academics and professionals, health personnel and educators, and policy-makers. The contents cover health-related differences between breast and bottle milk; patterns of…

  15. Tube Feedings.

    ERIC Educational Resources Information Center

    Plummer, Nancy

    This module on tube feedings is intended for use in inservice or continuing education programs for persons who work in long-term care. Instructor information, including teaching suggestions and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then provided. A brief discussion follows…

  16. Lysozymes and lysozyme-like proteins from the fall armyworm, Spodoptera frugiperda.

    PubMed

    Chapelle, Michael; Girard, Pierre-Alain; Cousserans, François; Volkoff, Nathalie-Anne; Duvic, Bernard

    2009-12-01

    Lysozyme is an important component of the insect non-specific immune response against bacteria that is characterized by its ability to break down bacterial cell-walls. By searching an EST database from the fall armyworm, Spodoptera frugiperda (Negre et al., 2006), we identified five sequences encoding proteins of the lysozyme family. The deduced protein sequences corresponded to three classical c-type lysozymes Sf-Lys1, Sf-Lys2 and Sf-Lys3, and two lysozyme-like proteins, Sf-LLP1 and Sf-LLP2. Sf-Lys1 was purified from the hemolymph of Escherichia coli-challenged S. frugiperda larvae. The mature protein had a molecular mass of 13.975 Da with an isoelectric point of 8.77 and showed 98.3% and 96.7% identity with lysozymes from Spodoptera litura and Spodoptera exigua, respectively. As the other insect lysozymes, Sf-Lys1 was active against gram positive bacteria such as Micrococcus luteus but also induced a slight permeabilization of the inner membrane of E. coli. Genes encoding these five Sf-Lys or Sf-LLPs were differentially up-regulated in three immune-competent tissues (hemocytes, fat body and gut) after challenges with non-pathogenic bacteria, E. coli and M. luteus, or entomopathogenic bacterium, Photorhabdus luminescens. Sf-Lys1 and Sf-Lys2 were mainly induced in fat body in the presence of E. coli or P. luminescens. Sf-Lys3, which had an acidic isoelectric point, was found to be the most up-regulated of all five Sf-Lys or Sf-LLPs in hemocytes and gut after challenge with P. luminescens. More molecular data are now available to investigate differences in physiological functions of these different members of the lysozyme superfamily.

  17. Tracking the origins and diet of an endemic island canid (Urocyon littoralis) across 7300 years of human cultural and environmental change

    NASA Astrophysics Data System (ADS)

    Hofman, Courtney A.; Rick, Torben C.; Maldonado, Jesús E.; Collins, Paul W.; Erlandson, Jon M.; Fleischer, Robert C.; Smith, Chelsea; Sillett, T. Scott; Ralls, Katherine; Teeter, Wendy; Vellanoweth, René L.; Newsome, Seth D.

    2016-08-01

    Understanding how human activities have influenced the foraging ecology of wildlife is important as our planet faces ongoing and impending habitat and climatic change. We review the canine surrogacy approach (CSA)-a tool for comparing human, dog, and other canid diets in the past-and apply CSA to investigate possible ancient human resource provisioning in an endangered canid, the California Channel Islands fox (Urocyon littoralis). We conducted stable isotope analysis of bone collagen samples from ancient and modern island foxes (n = 214) and mainland gray foxes (Urocyon cinereoargenteus, n = 24). We compare these data to isotope values of ancient humans and dogs, and synthesize 29 Accelerator Mass Spectrometry (AMS) radiocarbon dates that fine-tune the chronology of island foxes. AMS dates confirm that island foxes likely arrived during the early Holocene (>7300 cal BP) on the northern islands in the archipelago and during the middle Holocene (>5500 cal BP) on the southern islands. We found no evidence that island foxes were consistently using anthropogenic resources (e.g., food obtained by scavenging around human habitation sites or direct provisioning by Native Americans), except for a few individuals on San Nicolas Island and possibly on San Clemente and Santa Rosa islands. Decreases in U. littoralis carbon and nitrogen isotope values between prehistoric times and the 19th century on San Nicolas Island suggest that changes in human land use from Native American hunter-gatherer occupations to historical ranching had a strong influence on fox diet. Island foxes exhibit considerable dietary variation through time and between islands and have adapted to a wide variety of climatic and cultural changes over the last 7300 years. This generalist foraging strategy suggests that endemic island foxes may be resilient to future changes in resource availability.

  18. Pleistocene phylogeography and cryptic diversity of a tiger beetle, Calomera littoralis, in North-Eastern Mediterranean and Pontic regions inferred from mitochondrial COI gene sequences

    PubMed Central

    Rewicz, Tomasz; Płóciennik, Mateusz; Grabowski, Michał

    2016-01-01

    Background. Calomera littoralis is a Palearctic species, widely distributed in Europe; inhabiting predominantly its Atlantic, Mediterranean and Black Sea coastlines. Methods. Its phylogeography on the Balkan Peninsula and on the north-western Black Sea coast was inferred using a 697 bp long portion of the mitochondrial COI gene, amplified from 169 individuals collected on 43 localities. Results. The results revealed two genetically divergent groups/lineages, the southern one inhabiting both the Balkan Peninsula and the Pontic Region and the northern one found exclusively in the Pontic Region. Species delimitation based on DNA barcoding gap suggested an interspecific level of divergence between these groups. Multivariate analysis of eight male and female morphometric traits detected no difference between the groups, implying they may represent cryptic species. The Bayesian time-calibrated reconstruction of phylogeny suggested that the lineages diverged ca. 2.3 Ma, in early Pleistocene. Discussion. The presence of the two genetically divergent groups results most likely from contemporary isolation of the Pontic basin from the Mediterranean that broke the continuous strip of coastal habitats inhabited by C. littoralis. Demographic analyses indicated that both lineages have been in demographic and spatial expansion since ca. 0.15 Ma. It coincides with the terminal stage of MIS-6, i.e., Wartanian/Saalian glaciation, and beginning of MIS-5e, i.e., Eemian interglacial, during which, due to eustatic sea level rise, a wide connection between Mediterranean and the Pontic basin was re-established. This, along with re-appearance of coastal habitats could initiate north-east expansion of the southern lineage and its secondary contact with the northern one. The isolation of the Pontic basin from the Mediterranean during the Weichselian glaciation most likely did not have any effect on their phylogeography. PMID:27547517

  19. TOXICITY OF ALPINIA GALANGA (ZINGIBERACEAE) RHIZOME EXTRACTS AGAINST SPODOPTERA LITURA (LEPIDOPTERA: NOCTUIDAE).

    PubMed

    Puangsomchit, A; Bullangpoti, V; Pluempanupat, W

    2014-01-01

    The objective of this study was to develop an alternative strategy for the control of Spodoptera litura larvae by using botanical insecticides. Rhizomes of Alpinia galanga were extracted with hexane, dichloromethane, ethyl acetate and methanol, respectively. Each crude extract was examined for toxicity against the second instars of S. litura according to a topical application method. The dichloromethane extract was found to show the highest toxicity of all the extracts, with LD50 = 3177 and 2099 ppm at 24 and 48 h post-treatment, respectively.

  20. Biotransformation of alpha-terpineol by the larvae of common cutworm (Spodoptera litura).

    PubMed

    Miyazawa, Mitsuo; Ohsawa, Masashi

    2002-08-14

    Biotransformation of alpha-terpineol by the common cutworm (Spodoptera litura) larvae was investigated. alpha-Terpineol was mixed in an artificial diet, and the diet was fed to the larvae (fourth-fifth instar) of S. litura. Metabolites were isolated from the frass and analyzed spectroscopically. Main metabolites were 7-hydroxy-alpha-terpineol (p-menth-1-ene-7,8-diol) and oleuropeic acid (8-hydroxy-p-menth-1-en-7-oic acid). Intestinal bacteria from the frass of larvae did not participate in the metabolism of alpha-terpineol. alpha-Terpineol was preferentially oxidized at the C-7 position (allylic methyl group) by S. litura larvae.

  1. Evidence of recent interspecies horizontal gene transfer regarding nucleopolyhedrovirus infection of Spodoptera frugiperda.

    PubMed

    Barrera, Gloria Patricia; Belaich, Mariano Nicolás; Patarroyo, Manuel Alfonso; Villamizar, Laura Fernanda; Ghiringhelli, Pablo Daniel

    2015-11-25

    Baculoviruses are insect-associated viruses carrying large, circular double-stranded-DNA genomes with significant biotechnological applications such as biological pest control, recombinant protein production, gene delivery in mammals and as a model of DNA genome evolution. These pathogens infect insects from the orders Lepidoptera, Hymenoptera and Diptera, and have high species diversity which is expressed in their diverse biological properties including morphology, virulence or pathogenicity. Spodoptera frugiperda (Lepidoptera: Noctuidae), the fall armyworm, represents a significant pest for agriculture in America; it is a host for baculoviruses such as the Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) (Colombia strain, genotype A) having been classified as a Group II alphabaculovirus making it a very attractive target for bioinsecticidal use. Genome analysis by pyrosequencing revealed that SfMNPV ColA has 145 ORFs, 2 of which were not present in the other sequenced genotypes of the virus (SfMNPV-NicB, SfMNPV-NicG, SfMNPV-19 and SfMNPV-3AP2). An in-depth bioinformatics study showed that ORF023 and ORF024 were acquired by a recent homologous recombination process between Spodoptera frugiperda and Spodoptera litura (the Oriental leafworm moth) nucleopolyhedroviruses. Auxiliary genes are numerous in the affected locus which has a homologous region (hr3), a repetitive sequence associated with genome replication which became lost in SfColA along with 1 ORF. Besides, the mRNAs associated with two acquired genes appeared in the virus' life-cycle during the larval stage. Predictive studies concerning the theoretical proteins identified that ORF023 protein would be a phosphatase involved in DNA repair and that the ORF024 protein would be a membrane polypeptide associated with cell transport. The SfColA genome was thus revealed to be a natural recombinant virus showing evidence of recent horizontal gene transfer between different baculovirus species occurring

  2. Overexpression of the PAP1 Transcription Factor Reveals a Complex Regulation of Flavonoid and Phenylpropanoid Metabolism in Nicotiana tabacum Plants Attacked by Spodoptera litura

    PubMed Central

    Mitsunami, Tomoko; Nishihara, Masahiro; Galis, Ivan; Alamgir, Kabir Md; Hojo, Yuko; Fujita, Kohei; Sasaki, Nobuhiro; Nemoto, Keichiro; Sawasaki, Tatsuya; Arimura, Gen-ichiro

    2014-01-01

    Anthocyanin pigments and associated flavonoids have demonstrated antioxidant properties and benefits for human health. Consequently, current plant bioengineers have focused on how to modify flavonoid metabolism in plants. Most of that research, however, does not consider the role of natural biotic stresses (e.g., herbivore attack). To understand the influence of herbivore attack on the metabolic engineering of flavonoids, we examined tobacco plants overexpressing the Arabidopsis PAP1 gene (encoding an MYB transcription factor), which accumulated anthocyanin pigments and other flavonoids/phenylpropanoids. In comparison to wild-type and control plants, transgenic plants exhibited greater resistance to Spodoptera litura. Moreover, herbivory suppressed the PAP1-induced increase of transcripts of flavonoid/phenylpropanoid biosynthetic genes (e.g., F3H) and the subsequent accumulation of these genes' metabolites, despite the unaltered PAP1 mRNA levels after herbivory. The instances of down-regulation were independent of the signaling pathways mediated by defense-related jasmonates but were relevant to the levels of PAP1-induced and herbivory-suppressed transcription factors, An1a and An1b. Although initially F3H transcripts were suppressed by herbivory, after the S. litura feeding was interrupted, F3H transcripts increased. We hypothesize that in transgenic plants responding to herbivory, there is a complex mechanism regulating enriched flavonoid/phenylpropanoid compounds, via biotic stress signals. PMID:25268129

  3. Spatial differences in (Z)-3-hexen-1-ol production preferentially reduces Spodoptera litura larva attack on the young leaves of Nicotiana benthamiana.

    PubMed

    Zhang, Yuqian; Fu, Xiumin; Wang, Feiyan; Yang, Ziyin

    2016-11-01

    Plants synthesize specialized metabolites which possess extremely important ecological functions including direct defense, indirect defense, and signaling. The optimal defense theory (ODT) proposes that defensive metabolites are preferentially allocated to the tissues with high fitness value or in locations that are easily injured. In our present study, using the model plant Nicotiana benthamiana, we found that direct defense of N. benthamiana against Spodoptera litura (Fabricius) larvae showed spatial differences in the sites producing defensive chemicals. The upper leaves possessed significantly stronger direct defense ability than the middle and lower leaves. Interestingly, the strong defense ability of the upper leaves was not due to occurrences of well-known defensive metabolites such as nicotine and chlorogenic acid. After damage, the middle and lower leaves emitted higher amounts of (Z)-3-hexen-1-ol than the upper leaves, which could both attract larvae and significantly increase the amount of middle and lower leaf eaten by the larvae. The spatial difference in (Z)-3-hexen-1-ol emission may be due to spatial differences in expression of lipoxygenase (NbLOX2), which is responsible for the formation and emission of (Z)-3-hexen-1-ol. This study provided new insight into ODT, showing that plants effectively protect easily injured tissues through reduction in concentration of herbivore-feeding stimulant in the tissues.

  4. Overexpression of the PAP1 transcription factor reveals a complex regulation of flavonoid and phenylpropanoid metabolism in Nicotiana tabacum plants attacked by Spodoptera litura.

    PubMed

    Mitsunami, Tomoko; Nishihara, Masahiro; Galis, Ivan; Alamgir, Kabir Md; Hojo, Yuko; Fujita, Kohei; Sasaki, Nobuhiro; Nemoto, Keichiro; Sawasaki, Tatsuya; Arimura, Gen-ichiro

    2014-01-01

    Anthocyanin pigments and associated flavonoids have demonstrated antioxidant properties and benefits for human health. Consequently, current plant bioengineers have focused on how to modify flavonoid metabolism in plants. Most of that research, however, does not consider the role of natural biotic stresses (e.g., herbivore attack). To understand the influence of herbivore attack on the metabolic engineering of flavonoids, we examined tobacco plants overexpressing the Arabidopsis PAP1 gene (encoding an MYB transcription factor), which accumulated anthocyanin pigments and other flavonoids/phenylpropanoids. In comparison to wild-type and control plants, transgenic plants exhibited greater resistance to Spodoptera litura. Moreover, herbivory suppressed the PAP1-induced increase of transcripts of flavonoid/phenylpropanoid biosynthetic genes (e.g., F3H) and the subsequent accumulation of these genes' metabolites, despite the unaltered PAP1 mRNA levels after herbivory. The instances of down-regulation were independent of the signaling pathways mediated by defense-related jasmonates but were relevant to the levels of PAP1-induced and herbivory-suppressed transcription factors, An1a and An1b. Although initially F3H transcripts were suppressed by herbivory, after the S. litura feeding was interrupted, F3H transcripts increased. We hypothesize that in transgenic plants responding to herbivory, there is a complex mechanism regulating enriched flavonoid/phenylpropanoid compounds, via biotic stress signals.

  5. Lethal and sublethal effects of methoxyfenozide on the development, survival and reproduction of the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae).

    PubMed

    Zarate, N; Díaz, O; Martínez, A M; Figueroa, J I; Schneider, M I; Smagghe, G; Viñuela, E; Budia, F; Pineda, S

    2011-01-01

    The lethal and sublethal effects of the ecdysone agonist methoxyfenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyfenozide-treated diet to fifth instars until pupation in doses corresponding to the LC10 and LC25 for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC10 and 60% for the LC25 was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm.

  6. Accumulation of silicon in cacti native to the United States: characterization of silica bodies and cyclic oligosiloxanes in Stenocereus thurberi, Opuntia littoralis, Opuntia ficus-indica, and Opuntia stricta.

    PubMed

    Wright, Cynthia R; Waddell, Emanuel A; Setzer, William N

    2014-06-01

    Four different cactus species growing in the United States, Stenocereus thurberi growing in Organ Pipe Cactus National Monument, Arizona, Opuntia littoralis and Opuntia ficus-indica, growing on Santa Catalina Island, California, and Opuntia stricta, growing in northern Alabama, were examined for the presence of silica bodies (opaline phytoliths). Silica bodies were found in all four of these cactus species, parallelepiped-shaped crystals in S. thurberi, and starburst-shaped crystalline structures in the three Opuntia species. In addition, the essential oils of the four cactus species were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. To our surprise, S. thurberi, O. littoralis, and O. ficus-indica (but not O. stricta) essential oils contained cyclic oligosiloxanes. To our knowledge, cyclic oligosiloxanes have not been previously found as essential oil components.

  7. 40 CFR 180.1118 - Spodoptera exigua nuclear polyhedrosis virus; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... virus; exemption from the requirement of a tolerance. 180.1118 Section 180.1118 Protection of... polyhedrosis virus; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for the microbial pest control agent Spodoptera exigua nuclear polyhedrosis virus...

  8. 40 CFR 180.1118 - Spodoptera exigua nuclear polyhedrosis virus; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... virus; exemption from the requirement of a tolerance. 180.1118 Section 180.1118 Protection of... polyhedrosis virus; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for the microbial pest control agent Spodoptera exigua nuclear polyhedrosis virus...

  9. 40 CFR 180.1118 - Spodoptera exigua nuclear polyhedrosis virus; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... virus; exemption from the requirement of a tolerance. 180.1118 Section 180.1118 Protection of... polyhedrosis virus; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for the microbial pest control agent Spodoptera exigua nuclear polyhedrosis virus...

  10. 40 CFR 180.1118 - Spodoptera exigua nuclear polyhedrosis virus; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... virus; exemption from the requirement of a tolerance. 180.1118 Section 180.1118 Protection of... polyhedrosis virus; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for the microbial pest control agent Spodoptera exigua nuclear polyhedrosis virus...

  11. 40 CFR 180.1118 - Spodoptera exigua nuclear polyhedrosis virus; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... virus; exemption from the requirement of a tolerance. 180.1118 Section 180.1118 Protection of... polyhedrosis virus; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for the microbial pest control agent Spodoptera exigua nuclear polyhedrosis virus...

  12. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures

    USDA-ARS?s Scientific Manuscript database

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this cou...

  13. Tropical soda apple (Solanum viarum) mediated competition via induced resistance: Interaction between Gratiana boliviana, Spodoptera exigua and Frankliniella occidentalis

    USDA-ARS?s Scientific Manuscript database

    Survival assays were conducted with beet armyworm (BAW) Spodoptera exigua (Hübner), a tortoise beetle Gratiana bolivana Spaeth and western flower thrips (WFT) Frankliniella occidentalis (Pergande) on tropical soda apple (TSA) Solanum viarum Dunal, a relative of tomato. Both S. exigua and G. bolivia...

  14. Occurrence of entomopathogenic fungi and parasitic nematodes on Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae collected in Central Chiapas, Mexico

    USDA-ARS?s Scientific Manuscript database

    Fall armyworm larvae (FAW), Spodoptera frugiperda (J. E. Smith) were collected from whorl-stage cornfields, between the V2 and V4 stages, in 22 localities of Central, Chiapas, México, called "La Frailesca" during late June 2009 to determine the occurrence of native entomopathogens and parasitic nema...

  15. Identification and characterization of odv-e25 of Spodoptera litura multicapsid nucleopolyhedrovirus.

    PubMed

    Li, Zhaofei; Pan, Lijin; Yu, Hang; Li, Sainan; Zhang, Guoping; Pang, Yi

    2006-02-01

    Spodoptera litura multicapsid nucleopolyhedrovirus (SpltMNPV) odv-e25 is 684 bp long, potentially encoding 227 amino acids with a predicted molecular weight of 24.9 kDa. Homology analysis indicated that SpltMNPV ODV-E25 has 35-65% amino acid identity with that of other known baculoviruses. RT-PCR results revealed that the odv-e25 is transcribed actively at the late stage of infection and the mRNA start site was mapped within a consensus baculovirus late promoter sequence (TTAAG). Western blot analysis of odv-e25 expression with an antiserum made against 6 x His tagged ODV-E25 expressed in Escherichia coli indicated that it was present as a doublet of approximately 27 kDa from 24 h through 96 h in SpltMNPV-infected Spli-221 cells. Similar results were seen on Western blots of Spodoptera exigua (Se)MNPV-infected Se301 cells. Immunofluorescence analysis showed that ODV-E25 was predominantly present in the cytoplasm of SpltMNPV-infected cells and localized to the envelopes of occlusion-derived virus.

  16. Harmonia axyridis (Coleoptera: Coccinellidae) exhibits no preference between Bt and non-Bt maize fed Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Dutra, Carla C; Koch, Robert L; Burkness, Eric C; Meissle, Michael; Romeis, Joerg; Hutchison, William D; Fernandes, Marcos G

    2012-01-01

    A recent shift in managing insect resistance to genetically engineered (GE) maize consists of mixing non-GE seed with GE seed known as "refuge in a bag", which increases the likelihood of predators encountering both prey fed Bt and prey fed non-Bt maize. We therefore conducted laboratory choice-test feeding studies to determine if a predator, Harmonia axyridis, shows any preference between prey fed Bt and non-Bt maize leaves. The prey species was Spodoptera frugiperda, which were fed Bt maize (MON-810), expressing the single Cry1Ab protein, or non-Bt maize. The predators were third instar larvae and female adults of H. axyridis. Individual predators were offered Bt and non-Bt fed prey larvae that had fed for 24, 48 or 72 h. Ten and 15 larvae of each prey type were offered to third instar and adult predators, respectively. Observations of arenas were conducted at 1, 2, 3, 6, 15 and 24 h after the start of the experiment to determine the number and type of prey eaten by each individual predator. Prey larvae that fed on non-Bt leaves were significantly larger than larvae fed Bt leaves. Both predator stages had eaten nearly all the prey by the end of the experiment. However, in all combinations of predator stage and prey age, the number of each prey type consumed did not differ significantly. ELISA measurements confirmed the presence of Cry1Ab in leaf tissue (23-33 µg/g dry weight) and S. frugiperda (2.1-2.2 µg/g), while mean concentrations in H. axyridis were very low (0.01-0.2 µg/g). These results confirm the predatory status of H. axyridis on S. frugiperda and that both H. axyridis adults and larvae show no preference between prey types. The lack of preference between Bt-fed and non-Bt-fed prey should act in favor of insect resistance management strategies using mixtures of GE and non-GE maize seed.

  17. Harmonia axyridis (Coleoptera: Coccinellidae) Exhibits No Preference between Bt and Non-Bt Maize Fed Spodoptera frugiperda (Lepidoptera: Noctuidae)

    PubMed Central

    Dutra, Carla C.; Koch, Robert L.; Burkness, Eric C.; Meissle, Michael; Romeis, Joerg; Hutchison, William D.; Fernandes, Marcos G.

    2012-01-01

    A recent shift in managing insect resistance to genetically engineered (GE) maize consists of mixing non-GE seed with GE seed known as “refuge in a bag”, which increases the likelihood of predators encountering both prey fed Bt and prey fed non-Bt maize. We therefore conducted laboratory choice-test feeding studies to determine if a predator, Harmonia axyridis, shows any preference between prey fed Bt and non-Bt maize leaves. The prey species was Spodoptera frugiperda, which were fed Bt maize (MON-810), expressing the single Cry1Ab protein, or non-Bt maize. The predators were third instar larvae and female adults of H. axyridis. Individual predators were offered Bt and non-Bt fed prey larvae that had fed for 24, 48 or 72 h. Ten and 15 larvae of each prey type were offered to third instar and adult predators, respectively. Observations of arenas were conducted at 1, 2, 3, 6, 15 and 24 h after the start of the experiment to determine the number and type of prey eaten by each individual predator. Prey larvae that fed on non-Bt leaves were significantly larger than larvae fed Bt leaves. Both predator stages had eaten nearly all the prey by the end of the experiment. However, in all combinations of predator stage and prey age, the number of each prey type consumed did not differ significantly. ELISA measurements confirmed the presence of Cry1Ab in leaf tissue (23–33 µg/g dry weight) and S. frugiperda (2.1–2.2 µg/g), while mean concentrations in H. axyridis were very low (0.01–0.2 µg/g). These results confirm the predatory status of H. axyridis on S. frugiperda and that both H. axyridis adults and larvae show no preference between prey types. The lack of preference between Bt-fed and non-Bt-fed prey should act in favor of insect resistance management strategies using mixtures of GE and non-GE maize seed. PMID:23024772

  18. Integration of insecticidal protein Vip3Aa1 into Beauveria bassiana enhances fungal virulence to Spodoptera litura larvae by cuticle and per Os infection.

    PubMed

    Qin, Yi; Ying, Sheng-Hua; Chen, Ying; Shen, Zhi-Cheng; Feng, Ming-Guang

    2010-07-01

    The entomopathogenic fungus Beauveria bassiana acts slowly on insect pests through cuticle infection. Vegetative insecticidal proteins (Vip3A) of Bacillus thuringiensis kill lepidopteran pests rapidly, via per os infection, but their use for pest control is restricted to integration into transgenic plants. A transgenic B. bassiana strain (BbV28) expressing Vip3Aa1 (a Vip3A toxin) was thus created to infect the larvae of the oriental leafworm moth Spodoptera litura through conidial ingestion and cuticle adhesion. Vip3Aa1 ( approximately 88 kDa) was highly expressed in the conidial cytoplasm of BbV28 and was detected as a digested form ( approximately 62 kDa) in the larval midgut 18 and 36 h after conidial ingestion. The median lethal concentration (LC(50)) of BbV28 against the second-instar larvae feeding on cabbage leaves sprayed with conidial suspensions was 26.2-fold lower than that of the wild-type strain on day 3 and 1.1-fold lower on day 7. The same sprays applied to both larvae and leaves for their feeding reduced the LC(50) of the transformant 17.2- and 1.3-fold on days 3 and 7, respectively. Median lethal times (LT(50)s) of BbV28 were shortened by 23 to 35%, declining with conidial concentrations. The larvae infected by ingestion of BbV28 conidia showed typical symptoms of Vip3A action, i.e., shrinkage and palsy. However, neither LC(50) nor LT(50) trends differed between BbV28 and its parental strain if the infection occurred through the cuticle only. Our findings indicate that fungal conidia can be used as vectors for spreading the highly insecticidal Vip3A protein for control of foliage feeders such as S. litura.

  19. Integration of Insecticidal Protein Vip3Aa1 into Beauveria bassiana Enhances Fungal Virulence to Spodoptera litura Larvae by Cuticle and Per Os Infection▿

    PubMed Central

    Qin, Yi; Ying, Sheng-Hua; Chen, Ying; Shen, Zhi-Cheng; Feng, Ming-Guang

    2010-01-01

    The entomopathogenic fungus Beauveria bassiana acts slowly on insect pests through cuticle infection. Vegetative insecticidal proteins (Vip3A) of Bacillus thuringiensis kill lepidopteran pests rapidly, via per os infection, but their use for pest control is restricted to integration into transgenic plants. A transgenic B. bassiana strain (BbV28) expressing Vip3Aa1 (a Vip3A toxin) was thus created to infect the larvae of the oriental leafworm moth Spodoptera litura through conidial ingestion and cuticle adhesion. Vip3Aa1 (∼88 kDa) was highly expressed in the conidial cytoplasm of BbV28 and was detected as a digested form (∼62 kDa) in the larval midgut 18 and 36 h after conidial ingestion. The median lethal concentration (LC50) of BbV28 against the second-instar larvae feeding on cabbage leaves sprayed with conidial suspensions was 26.2-fold lower than that of the wild-type strain on day 3 and 1.1-fold lower on day 7. The same sprays applied to both larvae and leaves for their feeding reduced the LC50 of the transformant 17.2- and 1.3-fold on days 3 and 7, respectively. Median lethal times (LT50s) of BbV28 were shortened by 23 to 35%, declining with conidial concentrations. The larvae infected by ingestion of BbV28 conidia showed typical symptoms of Vip3A action, i.e., shrinkage and palsy. However, neither LC50 nor LT50 trends differed between BbV28 and its parental strain if the infection occurred through the cuticle only. Our findings indicate that fungal conidia can be used as vectors for spreading the highly insecticidal Vip3A protein for control of foliage feeders such as S. litura. PMID:20495052

  20. Bacillus thuringiensis Cry1Ia10 and Vip3Aa protein interactions and their toxicity in Spodoptera spp. (Lepidoptera).

    PubMed

    Bergamasco, V B; Mendes, D R P; Fernandes, O A; Desidério, J A; Lemos, M V F

    2013-02-01

    The polyphagous pests belonging to the genus Spodoptera are considered to be among the most important causes of damage and are widely distributed throughout the Americas'. Due to the extensive use of genetically modified plants containing Bacillus thuringiensis genes that code for insecticidal proteins, resistant insects may arise. To prevent the development of resistance, pyramided plants, which express multiple insecticidal proteins that act through distinct mode of actions, can be used. This study analyzed the mechanisms of action for the proteins Cry1Ia10 and Vip3Aa on neonatal Spodoptera frugiperda, Spodoptera albula, Spodoptera eridania and Spodoptera cosmioides larvae. The interactions of these toxins with receptors on the intestinal epithelial membrane were also analyzed by binding biotinylated toxins to brush border membrane vesicles (BBMVs) from the intestines of these insects. A putative receptor of approximately 65 kDa was found by ligand blotting in all of these species. In vitro competition assays using biotinylated proteins have indicated that Vip3Aa and Cry1Ia10 do not compete for the same receptor for S. frugiperda, S. albula and S. cosmioides and that Vip3Aa was more efficient than Cry1Ia10 when tested individually, by bioassays. A synergistic effect of the toxins in S. frugiperda, S. albula and S. cosmioides was observed when they were combined. However, in S. eridania, Cry1Ia10 and Vip3Aa might compete for the same receptor and through bioassays Cry1Ia10 was more efficient than Vip3Aa and showed an antagonistic effect when the proteins were combined. These results suggest that using these genes to develop pyramided plants may not prove effective in preventing the development of resistance in S. eridiana.

  1. Neuropeptides associated with the regulation of feeding in insects.

    PubMed

    Audsley, N; Weaver, R J

    2009-05-15

    The stomatogastric nervous system plays a pivotal role in feeding behaviour. Central to this system is the frontal ganglion, which is responsible for foregut motor activity, and hence the passage of food through the gut. Many insect peptides, which exhibit myoactivity on the visceral muscles of the gut in vitro, have been detected in the stomatogastric nervous system by immunochemical or mass spectrometric techniques. This localisation of myoactive peptides, particularly in the frontal ganglion, implies roles for these peptides in the neural control and modulation of feeding in insects. Insect sulfakinins, tachykinins, allatotropin and proctolin have all been shown to stimulate the foregut muscles, whereas myosuppressins, myoinhibitory peptides and allatostatins all inhibited spontaneous contractions of the foregut in a variety of insects. Some of these peptides, when injected, inhibited feeding in vivo. Both the A-type and B-type allatostatins suppressed feeding activity when injected into the cockroach, Blattella germanica and the Manduca sexta C-type allatostatin and allatotropin inhibited feeding when injected into the larvae of two noctuid moths, Lacanobia oleracea and Spodoptera frugiperda, respectively. Injection of sulfakinins into the fly Phormia regina, the locust Schistocera gregaria and the cockroach B. germanica also suppressed feeding, whereas silencing the sulfakinin gene through the injection of double stranded RNA resulted in an increase in food consumption in the cricket Gryllus bimaculatus. The regulation of feeding in insects is clearly very complex, and involves the interaction of a number of mechanisms, one of which is the release, either centrally or locally, of neuropeptides. However, the role of neuropeptides, their mechanisms of action, interactions with each other, and their release are still poorly understood. It is also unclear why insects possess such a number of different peptides, some with multiples copies or homologues, which

  2. Toxicity and physiological effect of quercetin on generalist herbivore, Spodoptera litura Fab. and a non-target earthworm Eisenia fetida Savigny

    USDA-ARS?s Scientific Manuscript database

    A novel flavonoid, quercetin, was isolated from Euphorbia hirta L., a medicinal plant using chromatography techniques including: Thin-layer chromatography, Column chromatography, Nuclear magnetic resonance spectroscopy. Toxicity to larval of Spodoptera litura analyze pupal weight, survival rate, fec...

  3. Target and non-target toxicity of botanical insecticide derived from Couroupita guianensis L. flower against generalist herbivore, Spodoptera litura Fab. and an earthworm, Eisenia foetida Savigny

    USDA-ARS?s Scientific Manuscript database

    Novel chemistries in botanical insecticides may provide alternatives to, or development of synthetic insecticides suitable for controlling the Lepidopteran pests, like Spodoptera litura (F.). Many botanical chemistries are biodegradable, and have lower mammalian toxicity. Eight natural chemical comp...

  4. Behavior of larval Culicoides Sonorensis (Diptera: Ceratopogonidae) in response to an invertebrate predator, Hydra Littoralis (Anthomedusae: Hydridae)

    USDA-ARS?s Scientific Manuscript database

    Larvae of Culicoides sonorensis a blood feeding ceratopogonid are aquatic. In their natural habitat they are exposed to numerous predators. Predator avoidance behavior has not been studied in most Culicoides spp. Based on laboratory data the larvae of Culicoides sonorensis behave differently when cn...

  5. TOXICITY OF THE SEEDS OF PHASEOLUS LATHYROIDES (LEGUMINOSAE) AGAINST SPODOPTERA LITURA (LEPIDOPTERA: NOCTUIDAE).

    PubMed

    Pipattanaporn, P; Tharamak, S; Temyarasilp, P; Bullangpoti, V; Pluempanupat, W

    2015-01-01

    The seeds of Phaseolus lathyroides were extracted with hexane, dichloromethane, ethyl acetate and methanol, respectively by Soxhlet apparatus. Each crude extract was examined for toxicity against the second instars of Spodoptera litura using a topical application method under laboratory conditions. The ethyl acetate extract showed the most effective mortality (LD₅₀ = 11,964 and 9,169 ppm after treated at 24 and 48 hours, respectively). Furthermore, in vivo enzyme based experiments revealed that acetylcholinesterase activity of survived S. litura (24 hours post-treatment) was increased by 12% compared to control experiments. Our result showed the possibility to develop alternative strategies by using extract from the seeds of Phaseolus lathyroides for the control of S. litura.

  6. Purification of a human alternative complement pathway inhibitor from hemolymph of larval fall armyworm (Spodoptera frugiperda).

    PubMed

    D'Cruz, O J; Day, N K

    1984-08-16

    Larval Spodoptera frugiperda hemolymph contains a specific inhibitor of the alternative pathway of human complement. This inhibitor was purified from larval hemolymph (HL) by 50% (NH4)2SO4 precipitation, DEAE-Sephacel chromatography and sequential gel-filtration on Bio-Gel 1.5m, 0.5m and Sephacryl S-200. Purified HL protein (Mr = 110,000) was composed of two Mr 55,000 polypeptide chains. Addition of purified HL protein to human complement resulted in a dose-dependent inhibition of RaRBC lysis and clumping of cells. The protein inhibitor provides a new tool for investigating the regulation of human alternative complement pathway.

  7. The complete mitochondrial genome of the common cutworm, Spodoptera litura (Lepidoptera: Noctuidade).

    PubMed

    Liu, Qiu-Ning; Zhu, Bao-Jian; Dai, Li-Shang; Wang, Lei; Qian, Cen; Wei, Guo-Qing; Liu, Chao-Liang

    2016-01-01

    The complete mitochondrial genome (mitogenome) of Spodoptera litura (Lepidoptera: Noctuidae) was determined to be 15,374 bp (GenBank accession No. KF543065), including 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and an A + T-rich region. It has the typical gene organization and order of mitogenomes from lepidopteran insects. The AT skew of this mitogenome was slightly positive and the nucleotide composition was also biased toward A + T nucleotides (81.03%). All PCGs were initiated by ATN codons, except for cytochrome c oxidase subunit 1 (cox1) gene which was initiated by CGA. Four of the 13 PCGs harbor the incomplete termination codon by T. All the tRNA genes displayed a typical clover-leaf structure of mitochondrial tRNA, with the exception of trnS1 (AGN). The A + T-rich region of the mitogenome was 326 bp in length.

  8. Toxicity of selected tremorgenic mycotoxins and related compounds to Spodoptera frugiperda and Heliothis zea.

    PubMed

    Dowd, P F; Cole, R J; Vesonder, R F

    1988-12-01

    A series of tremorgenic mycotoxins and related compounds were tested for oral toxicity to the fall armyworm (Spodoptera frugiperda) and corn earworm (Heliothis zea) by incorporation of materials into artificial diets and examining mortality and weights after 7 days. Significant mortality to both insect species was caused with dihydroxyaflavinine and roseotoxin B, while significant mortality to H. zea was also caused by penitrem A at 25 ppm. After 7 days, weighs of larvae treated with 25 ppm penitrem A, roseotoxin B, and verruculogen were less than 50% of controls for both insect species. Weights of H. zea larvae treated with 25 ppb of penitrem A were less than 50% those of control larvae. Relative toxicities of the tremorgens and related compounds to insects compared to vertebrates are discussed.

  9. Life history of Spodoptera exigua (Lepidoptera: Noctuidae) on various host plants.

    PubMed

    Azidah, A A; Sofian-Azirun, M

    2006-12-01

    The incubation period of Spodoptera exigua (Hübner) was not influenced by the host plant, whereas larval development time and pupal period were affected. Larval development time was longest on shallot and lady's finger, followed by cabbage and long bean. Larvae did not develop beyond the first instar when fed on chilli. The pupal period was longer on lady's finger than on cabbage, shallot and long bean. Overall, adult longevity was not influenced by the host plant but there was a difference between female and male longevity among the host plants. Survival of S. exigua was affected by the host plant at the larval stage. The number of larval instars varied between 5 and 8 within and between the studied host plants. Long bean was found to be the most suitable host plant and provide the best food quality for S. exigua compared to the other host plants, as it allowed faster development, fewer larval instars and a higher survival rate.

  10. Vip3Aa induces apoptosis in cultured Spodoptera frugiperda (Sf9) cells.

    PubMed

    Jiang, Kun; Mei, Si-Qi; Wang, Ting-Ting; Pan, Jin-Hua; Chen, Yue-Hua; Cai, Jun

    2016-09-15

    The vegetative insecticidal proteins (Vip) secreted by many Bacillus thuringiensis strains during their vegetative growth stage are regarded as second generation insecticidal proteins, as they share no sequence or structural homology with known crystal insecticidal proteins (Cry) and have a broad insecticidal spectrum. Compared with insecticidal crystal proteins (ICPs), the insecticidal mechanisms of Vips have been little studied. Here we investigated the mechanism responsible for Vip3Aa toxicity in cultured insect cells. Using, flow cytometry analyzes, TUNEL staining and DNA fragmentation assays, we show that Vip3Aa can induce apoptosis in Spodoptera frugiperda (Sf9) cells and cause cells to arrest at the G2/M phase. We also show that Vip3Aa can disrupt mitochondrial membrane potential (ΔΨm), leading to the activation of Sf-caspase-1, suggesting that a mitochondrial mediated and caspase dependent pathway may be involved in Vip3Aa-induced apoptosis in Sf9 cells.

  11. DNA restriction polymorphism in wild isolates of Spodoptera frugiperda nuclear polyhedrosis virus.

    PubMed

    Shapiro, D I; Fuxa, J R; Braymer, H D; Pashley, D P

    1991-07-01

    Restriction endonuclease analysis was used to examine variation in DNA of 22 wild isolates of Spodoptera frugiperda nuclear polyhedrosis virus (SfNPV). Eleven of the 15 isolated from Louisiana were distinguishable based on restriction fragment profiles from the enzymes BamHI, HindIII, and EcoRI. There was significant genetic variation in SfNPV isolates within single agricultural fields. Nucleotide sequence divergence values, based on restriction fragment profiles, indicated that genetic variation among isolates foreign to Louisiana (Ohio, Ecuador, Mexico, Georgia, Colombia, and Venezuela) was greater than that among the Louisiana isolates. However, certain foreign isolates were similar to or identical with Louisiana isolates. Genetic variation of the viral DNA was not influenced by the insect's host plan species.

  12. Microsatellite markers for genetic studies of the fall armyworm, Spodoptera frugiperda.

    PubMed

    Pavinato, V A C; Martinelli, S; de Lima, P F; Zucchi, M I; Omoto, C

    2013-02-08

    We developed six microsatellite markers for the fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). The SSR loci were isolated with enriched genomic library protocol by using native individuals as a genome source for markers. These loci were characterized in 48 individuals and they were tested for the ability to identify candidate migrants exchanged among the samples. The number of alleles per locus ranged from 5 to 18 (10.8 on average). The observed polymorphism information content ranged from 0.172 to 0.891. Beside the lower efficiency to obtain SSR loci, the six microsatellites were polymorphic and sufficiently discriminant for the genetic studies of S. frugiperda; it allowed us to identify migrants with both NJ clustering and the Bayesian methods. These markers will be useful for molecular ecology studies of this highly polyphagous species in order to understand the processes that determine genetic differentiation in the complex agro-ecosystems that it infests and improve local integrated pest management practices.

  13. Analysis and functional annotation of expressed sequence tags from the fall armyworm Spodoptera frugiperda.

    PubMed

    Deng, Youping; Dong, Yinghua; Thodima, Venkata; Clem, Rollie J; Passarelli, A Lorena

    2006-10-19

    Little is known about the genome sequences of lepidopteran insects, although this group of insects has been studied extensively in the fields of endocrinology, development, immunity, and pathogen-host interactions. In addition, cell lines derived from Spodoptera frugiperda and other lepidopteran insects are routinely used for baculovirus foreign gene expression. This study reports the results of an expressed sequence tag (EST) sequencing project in cells from the lepidopteran insect S. frugiperda, the fall armyworm. We have constructed an EST database using two cDNA libraries from the S. frugiperda-derived cell line, SF-21. The database consists of 2,367 ESTs which were assembled into 244 contigs and 951 singlets for a total of 1,195 unique sequences. S. frugiperda is an agriculturally important pest insect and genomic information will be instrumental for establishing initial transcriptional profiling and gene function studies, and for obtaining information about genes manipulated during infections by insect pathogens such as baculoviruses.

  14. Flavonoids of zoysiagrass (Zoysia spp.) cultivars varying in fall armyworm (Spodoptera frugiperda) resistance.

    PubMed

    Anderson, William F; Snook, Maurice E; Johnson, Albert W

    2007-03-07

    Flavonoid profiles of 12 zoysiagrass (Zoysia spp.) cultivars sampled six times in 1998 were correlated to fall armyworm (Spodoptera frugiperda J. E. Smith) larval weights and survival on replicated field-grown plant material and analyzed to determine genetic and seasonal variations of flavonoids among zoysiagrass cultivars. From multiple regression analyses and correlations, flavonoid peak 10 (luteolin-glucoside) had the greatest positive association with average fall armyworm weight; however, resistance appeared to be correlated with a number of other flavonoids. The flavonoid profiles of cultivars subjected to clustering procedures showed consistent genetic variability for five of six samplings and was used to genotype 23 cultivars. The dendrogram supported the results of the FASTCLUS procedure in clustering certain genotypes such as fall armyworm-resistant Cavalier and Zeon together, as well as J-36 and Meyer. Flavonoid evaluations measure genetic relatedness among cultivars and could be used for selective breeding of resistance to fall armyworm.

  15. Synthesis of a combinatorial library of amides and its evaluation against the fall armyworm, Spodoptera frugiperda.

    PubMed

    Castral, Thais C; Matos, Andreia P; Monteiro, Julia L; Araujo, Fernanda M; Bondancia, Tatiani M; Batista-Pereira, Luciane G; Fernandes, João B; Vieira, Paulo C; da Silva, M Fatima G F; Corrêa, Arlene G

    2011-05-11

    The fall armyworm Spodoptera frugiperda is a polyphagous pest that causes important damage in different regions of America and mainly affects corn crops in both tropical and subtropical areas. Currently, control relies on both transgenic plants and/or chemical pesticides. In this work we describe the preparation of an indexed combinatorial library of amides and its toxic effect by contact against S. frugiperda . (E)-1-(1-Piperidinyl)-3-[4-(trifluoromethoxy)phenyl]-2-propen-1-one was the most active compound with an LD(50) = 0.793 μg mg(-1) of larva. This amide was also evaluated by ingestion and at the lowest concentration (1 mg kg(-1)) achieved 83.3% mortality.

  16. Identification and functional characterization of sex pheromone receptors in the common cutworm (Spodoptera litura).

    PubMed

    Zhang, Jin; Yan, Shuwei; Liu, Yang; Jacquin-Joly, Emmanuelle; Dong, Shuanglin; Wang, Guirong

    2015-01-01

    Male moths can finely discriminate the sex pheromone emitted by conspecific females from similar compounds. Pheromone receptors, expressed on the dendritic membrane of sensory neurons housed in the long trichoid sensilla of antennae, are thought to be associated with the pheromone reception. In this study, we identified and functionally characterized 4 pheromone receptors from the antennae of Spodoptera litura (Lepidoptera: Noctuidae). A tissue distribution analysis showed that the expression of the 4 SlituPRs was restricted to antennae. In addition, SlituOR6 and SlituOR13 were specifically expressed in male antennae whereas SlituOR11 and SlituOR16 were male-biased. Functional investigation by heterologous expression in Xenopus oocytes revealed that SlituOR6 was specifically tuned to the second major pheromone component, Z9,E12-14:OAc, SlituOR13 was equally tuned to Z9,E12-14:OAc and Z9-14:OAc, with a small response to the major pheromone component Z9,E11-14:OAc, SlituOR16 significantly responded to the behavioral antagonist Z9-14:OH, whereas SlituOR11 did not show response to any of the pheromone compounds tested in this study. Our results provide molecular data to better understand the mechanisms of sex pheromone detection in the moth S. litura and bring clues to investigate the evolution of the sexual communication channel in closely related species through comparison with previously reported pheromone receptors in other Spodoptera species.

  17. Status of resistance to Bt maize in Spodoptera frugiperda: lessons from Puerto Rico.

    PubMed

    Storer, Nicholas P; Kubiszak, Mary E; Ed King, J; Thompson, Gary D; Santos, Antonio Cesar

    2012-07-01

    In 2006, reports of potential Spodoptera frugiperda resistance to TC1507 maize in Puerto Rico were received. Subsequent investigation confirmed that pest populations collected from several sites in Puerto Rico were largely unaffected by the Cry1F protein in bioassays, with resistance ratios likely in excess of 1000. Since then, we have continued monitoring populations in Puerto Rico and in southern areas of the mainland US. The majority of the collections from Puerto Rico continue to show high levels of Cry1F resistance whereas populations collected from the southern US mainland continue to show full susceptibility to Cry1F and TC1507 maize. It does not appear that resistant populations have spread to any measurable extent from Puerto Rico to mainland US, nor that local selection pressure from Cry1F-expressing maize or cotton production in the southern US has caused a measurable change in population susceptibility. Lessons learned from Puerto Rico are being applied in other parts of the Americas where TC1507 maize is grown and additional steps being taken to protect the long-term durability of Cry1F in maize in areas where similar selection pressure may be expected. Tactics include using locally-adapted germplasm that contain native Spodoptera resistance, a robust education program to teach end-users about the potential for resistance to develop appropriate crop stewardship, resistance monitoring, and the use of insecticides under high S. frugiperda pressure. Perhaps most importantly, pyramided trait products that produce two or more different Bt proteins are being introduced to further delay resistance development to Cry1F. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Insect antifeedant furanocoumarins from Tetradium daniellii.

    PubMed

    Stevenson, Philip C; Simmonds, Monique S J; Yule, Marianne A; Veitch, Nigel C; Kite, Geoffrey C; Irwin, Dianne; Legg, Mike

    2003-05-01

    The dried fruits of Tetradium daniellii yielded a new linear furanocoumarin, 5-(6-hydroxy-3,7-dimethylocta-2,7-dienyloxy)psoralen, together with six other structurally related furanocoumarins. A similar chemical profile was recorded by HPLC analysis of a fragment of T. daniellii fruit obtained from an historic herbarium voucher specimen collected in September 1917 during an expedition to Yunnan province, China. Four of the compounds identified caused a potent feeding deterrent effect towards larvae of Spodoptera littoralis and Heliothis virescens.

  19. Pathology and Epidemiology of Ceruminous Gland Tumors among Endangered Santa Catalina Island Foxes (Urocyon littoralis catalinae) in the Channel Islands, USA

    PubMed Central

    Vickers, T. Winston; Clifford, Deana L.; Garcelon, David K.; King, Julie L.; Duncan, Calvin L.; Gaffney, Patricia M.; Boyce, Walter M.

    2015-01-01

    In this study, we examined the prevalence, pathology, and epidemiology of tumors in free-ranging island foxes occurring on three islands in the California Channel Islands, USA. We found a remarkably high prevalence of ceruminous gland tumors in endangered foxes (Urocyon littoralis catalinae) occurring on Santa Catalina Island (SCA)—48.9% of the dead foxes examined from 2001–2008 had tumors in their ears, and tumors were found in 52.2% of randomly-selected mature (≥ 4 years) foxes captured in 2007–2008, representing one of the highest prevalences of tumors ever documented in a wildlife population. In contrast, no tumors were detected in foxes from San Nicolas Island or San Clemente Island, although ear mites (Otodectes cynotis), a predisposing factor for ceruminous gland tumors in dogs and cats, were highly prevalent on all three islands. On SCA, otitis externa secondary to ear mite infection was highly correlated with ceruminous gland hyperplasia (CGH), and tumors were significantly associated with the severity of CGH, ceruminous gland dysplasia, and age group (older foxes). We propose a conceptual model for the formation of ceruminous gland tumors in foxes on SCA that is based on persistent, ubiquitous infection with ear mites, and an innate, over exuberant inflammatory and hyperplastic response of SCA foxes to these mites. Foxes on SCA are now opportunistically treated with acaricides in an attempt to reduce mite infections and the morbidity and mortality associated with this highly prevalent tumor. PMID:26618759

  20. Pathology and Epidemiology of Ceruminous Gland Tumors among Endangered Santa Catalina Island Foxes (Urocyon littoralis catalinae) in the Channel Islands, USA.

    PubMed

    Vickers, T Winston; Clifford, Deana L; Garcelon, David K; King, Julie L; Duncan, Calvin L; Gaffney, Patricia M; Boyce, Walter M

    2015-01-01

    In this study, we examined the prevalence, pathology, and epidemiology of tumors in free-ranging island foxes occurring on three islands in the California Channel Islands, USA. We found a remarkably high prevalence of ceruminous gland tumors in endangered foxes (Urocyon littoralis catalinae) occurring on Santa Catalina Island (SCA)--48.9% of the dead foxes examined from 2001-2008 had tumors in their ears, and tumors were found in 52.2% of randomly-selected mature (≥ 4 years) foxes captured in 2007-2008, representing one of the highest prevalences of tumors ever documented in a wildlife population. In contrast, no tumors were detected in foxes from San Nicolas Island or San Clemente Island, although ear mites (Otodectes cynotis), a predisposing factor for ceruminous gland tumors in dogs and cats, were highly prevalent on all three islands. On SCA, otitis externa secondary to ear mite infection was highly correlated with ceruminous gland hyperplasia (CGH), and tumors were significantly associated with the severity of CGH, ceruminous gland dysplasia, and age group (older foxes). We propose a conceptual model for the formation of ceruminous gland tumors in foxes on SCA that is based on persistent, ubiquitous infection with ear mites, and an innate, over exuberant inflammatory and hyperplastic response of SCA foxes to these mites. Foxes on SCA are now opportunistically treated with acaricides in an attempt to reduce mite infections and the morbidity and mortality associated with this highly prevalent tumor.

  1. Alkaloids from beach spider lily (Hymenocallis littoralis) induce apoptosis of HepG-2 cells by the fas-signaling pathway.

    PubMed

    Ji, Yu-Bin; Chen, Ning; Zhu, Hong-Wei; Ling, Na; Li, Wen-Lan; Song, Dong-Xue; Gao, Shi-Yong; Zhang, Wang-Cheng; Ma, Nan-Nan

    2014-01-01

    Alkaloids are the most extensively featured compounds of natural anti-tumor herbs, which have attracted much attention in pharmaceutical research. In our previous studies, a mixture of major three alkaloid components (5, 6-dihydrobicolorine, 7-deoxy-trans-dihydronarciclasine, littoraline) from Hymenocallis littoralis were extracted, analyzed and designated as AHL. In this paper, AHL extracts were added to human liver hepatocellular cells HepG-2, human gastric cancer cell SGC-7901, human breast adenocarcinoma cell MCF-7 and human umbilical vein endothelial cell EVC-304, to screen one or more AHL-sensitive tumor cell. Among these cells, HepG-2 was the most sensitive to AHL treatment, a very low dose (0.8μg/ml) significantly inhibiting proliferation . The non- tumor cell EVC-304, however, was not apparently affected. Effect of AHL on HepG-2 cells was then explored. We found that the AHL could cause HepG-2 cycle arrest at G2/M checkpoint, induce apoptosis, and interrupt polymerization of microtubules. In addition, expression of two cell cycle-regulated proteins, CyclinB1 and CDK1, was up-regulated upon AHL treatment. Up-regulation of the Fas, Fas ligand, Caspase-8 and Caspase-3 was observed as well, which might imply roles for the Fas/FsaL signaling pathway in the AHL-induced apoptosis of HepG-2 cells.

  2. Cytoskeleton organisation during the infection of three brown algal species, Ectocarpus siliculosus, Ectocarpus crouaniorum and Pylaiella littoralis, by the intracellular marine oomycete Eurychasma dicksonii.

    PubMed

    Tsirigoti, A; Küpper, F C; Gachon, C M M; Katsaros, C

    2014-01-01

    Oomycete diseases in seaweeds are probably widespread and of significant ecological and economic impact, but overall still poorly understood. This study investigates the organisation of the cytoskeleton during infection of three brown algal species, Pylaiella littoralis, Ectocarpus siliculosus, and Ectocarpus crouaniorum, by the basal marine oomycete Eurychasma dicksonii. Immunofluorescence staining of tubulin revealed how the development of this intracellular biotrophic pathogen impacts on microtubule (MT) organisation of its algal host. The host MT cytoskeleton remains normal and organised by the centrosome until very late stages of the infection. Additionally, the organisation of the parasite's cytoskeleton was examined. During mitosis of the E. dicksonii nucleus the MT focal point (microtubule organisation centre, MTOC, putative centrosome) duplicates and each daughter MTOC migrates to opposite poles of the nucleus. This similarity in MT organisation between the host and pathogen reflects the relatively close phylogenetic relationship between oomycetes and brown algae. Moreover, actin labelling with rhodamine-phalloidin in E. dicksonii revealed typical images of actin dots connected by fine actin filament bundles in the cortical cytoplasm. The functional and phylogenetic implications of our observations are discussed.

  3. A tritrophic signal that attracts parasitoids to host-damaged plants withstands disruption by non-host herbivores

    PubMed Central

    2010-01-01

    Background Volatiles emitted by herbivore-infested plants are highly attractive to parasitoids and therefore have been proposed to be part of an indirect plant defense strategy. However, this proposed function of the plant-provided signals remains controversial, and it is unclear how specific and reliable the signals are under natural conditions with simultaneous feeding by multiple herbivores. Phloem feeders in particular are assumed to interfere with plant defense responses. Therefore, we investigated how attack by the piercing-sucking cicadellid Euscelidius variegatus influences signaling by maize plants in response to the chewing herbivore Spodoptera littoralis. Results The parasitoid Cotesia marginiventris strongly preferred volatiles of plants infested with its host S. littoralis. Overall, the volatile emissions induced by S. littoralis and E. variegatus were similar, but higher levels of certain wound-released compounds may have allowed the wasps to specifically recognize plants infested by hosts. Expression levels of defense marker genes and further behavioral bioassays with the parasitoid showed that neither the physiological defense responses nor the attractiveness of S. littoralis infested plants were altered by simultaneous E. variegatus attack. Conclusions Our findings imply that plant defense responses to herbivory can be more robust than generally assumed and that ensuing volatiles convey specific information about the type of herbivore that is attacking a plant, even in complex situations with multiple herbivores. Hence, the results of this study support the notion that herbivore-induced plant volatiles may be part of a plant's indirect defense stratagem. PMID:21078181

  4. Differential Protection of Cry1Fa Toxin against Spodoptera frugiperda Larval Gut Proteases by Cadherin Orthologs Correlates with Increased Synergism

    PubMed Central

    Rahman, Khalidur; Abdullah, Mohd Amir F.; Ambati, Suresh; Taylor, Milton D.

    2012-01-01

    The Cry proteins produced by Bacillus thuringiensis (Bt) are the most widely used biopesticides effective against a range of crop pests and disease vectors. Like chemical pesticides, development of resistance is the primary threat to the long-term efficacy of Bt toxins. Recently discovered cadherin-based Bt Cry synergists showed the potential to augment resistance management by improving efficacy of Cry toxins. However, the mode of action of Bt Cry synergists is thus far unclear. Here we elucidate the mechanism of cadherin-based Cry toxin synergism utilizing two cadherin peptides, Spodoptera frugiperda Cad (SfCad) and Manduca sexta Cad (MsCad), which differentially enhance Cry1Fa toxicity to Spodoptera frugiperda neonates. We show that differential SfCad- and MsCad-mediated protection of Cry1Fa toxin in the Spodoptera frugiperda midgut correlates with differential Cry1Fa toxicity enhancement. Both peptides exhibited high affinity for Cry1Fa toxin and an increased rate of Cry1Fa-induced pore formation in S. frugiperda. However, only SfCad bound the S. frugiperda brush border membrane vesicle and more effectively prolonged the stability of Cry1Fa toxin in the gut, explaining higher Cry1Fa enhancement by this peptide. This study shows that cadherin fragments may enhance B. thuringiensis toxicity by at least two different mechanisms or a combination thereof: (i) protection of Cry toxin from protease degradation in the insect midgut and (ii) enhancement of pore-forming ability of Cry toxin. PMID:22081566

  5. Strong oviposition preference for Bt over non-Bt maize in Spodoptera frugiperda and its implications for the evolution of resistance

    PubMed Central

    2014-01-01

    Background Transgenic crops expressing Bt toxins have substantial benefits for growers in terms of reduced synthetic insecticide inputs, area-wide pest management and yield. This valuable technology depends upon delaying the evolution of resistance. The ‘high dose/refuge strategy’, in which a refuge of non-Bt plants is planted in close proximity to the Bt crop, is the foundation of most existing resistance management. Most theoretical analyses of the high dose/refuge strategy assume random oviposition across refugia and Bt crops. Results In this study we examined oviposition and survival of Spodoptera frugiperda across conventional and Bt maize and explored the impact of oviposition behavior on the evolution of resistance in simulation models. Over six growing seasons oviposition rates per plant were higher in Bt crops than in refugia. The Cry1F Bt maize variety retained largely undamaged leaves, and oviposition preference was correlated with the level of feeding damage in the refuge. In simulation models, damage-avoiding oviposition accelerated the evolution of resistance and either led to requirements for larger refugia or undermined resistance management altogether. Since larval densities affected oviposition preferences, pest population dynamics affected resistance evolution: larger refugia were weakly beneficial for resistance management if they increased pest population sizes and the concomitant degree of leaf damage. Conclusions Damaged host plants have reduced attractiveness to many insect pests, and crops expressing Bt toxins are generally less damaged than conventional counterparts. Resistance management strategies should take account of this behavior, as it has the potential to undermine the effectiveness of existing practice, especially in the tropics where many pests are polyvoltinous. Efforts to bring down total pest population sizes and/or increase the attractiveness of damaged conventional plants will have substantial benefits for slowing the

  6. Comprehensive analysis of gene expression profiles of the beet armyworm Spodoptera exigua larvae challenged with Bacillus thuringiensis Vip3Aa toxin.

    PubMed

    Bel, Yolanda; Jakubowska, Agata K; Costa, Juliana; Herrero, Salvador; Escriche, Baltasar

    2013-01-01

    Host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. Vip proteins, which are Bacillus thuringensis (Bt) insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. This new group of Bt proteins represents an interesting alternative to the classical Bt Cry toxins because current data suggests that they do not share the same mode of action. We have designed and developed a genome-wide microarray for the beet armyworm Spodoptera exigua, a serious lepidopteran pest of many agricultural crops, and used it to better understand how lepidopteran larvae respond to the treatment with the insecticidal protein Vip3Aa. With this approach, the goal of our study was to evaluate the changes in gene expression levels caused by treatment with sublethal doses of Vip3Aa (causing 99% growth inhibition) at 8 and 24 h after feeding. Results indicated that the toxin provoked a wide transcriptional response, with 19% of the microarray unigenes responding significantly to treatment. The number of up- and down-regulated unigenes was very similar. The number of genes whose expression was regulated at 8 h was similar to the number of genes whose expression was regulated after 24 h of treatment. The up-regulated sequences were enriched for genes involved in innate immune response and in pathogen response such as antimicrobial peptides (AMPs) and repat genes. The down-regulated sequences were mainly unigenes with homology to genes involved in metabolism. Genes related to the mode of action of Bt Cry proteins were found, in general, to be slightly overexpressed. The present study is the first genome-wide analysis of the response of lepidopteran insects to Vip3Aa intoxication. An insight into the molecular mechanisms and components related to Vip intoxication will allow designing of more effective management strategies for pest control.

  7. The effect of the combination of two biological control agents, Mirabilis jalapa and Bacillus thuringiensis, to Spodoptera litura's immune response and their mortality

    NASA Astrophysics Data System (ADS)

    Maulina, Dina; Anggraeni, Tjandra

    2014-03-01

    Biological control provides a safer alternative to reduce the population of agricultural pest. Mirabilis jalapa is one of many promising biopesticides which contains chemical substances that have a feeding deterrent property against insects. This biopesticide may not kill insect directly but will weaken their overall physiological condition. In this study, we investigated the immune response of common pestSpodoptera litura after exposure of M. jalapa extract. We also used Bacillus thuringiensis (Bt) delta endotoxin (LC50) on 3 hours after exposure of M. jalapa extract to see the synergism properties of both biopesticide agents. Microscopic observation revealed that at least 5 types of haemocyte were found in S. litura. In control group, plasmatocyte were found at 59.98%, prohaemocyte 20.73%, granullar cell 12.74%, oenocytoid 3.33% and spherule cell 3.20%. These proportion was differ significantly in the treatment group. Exposure to 0.1% and 0.2%(w/v) of M. jalapa extract increased the total number of haemocytes as much as 38.08% and 64.15% respectively. In contrast, exposure to 0.4% and 0.8%(w/v) reduced the number of haemocytes to 37.02% and 51.04% respectively. In term of phagocytic activity, the proportion of phagocytosing cells were 47.62% in control group, and in 0.1% and 0.2% (w/v) M. jalapa treatment group the proportion decreased to 28% and 26.88% respectively. In the concentration of 0.4% and 0.8%, phagocytic activity did not occur. Addition of biological agents Bt (LC50 concentration) to see mortality 3 hours after M. jalapa application did not show significant differences. S. litura mortality rate were found only 50%; this suggests that the combination of M. jalapa and Bt biopesticides in 3-hour intervals within 24 hours showed no increase in mortality.

  8. Expression analysis of two P450 monooxygenase genes of the tobacco cutworm moth (Spodoptera litura) at different developmental stages and in response to plant allelochemicals.

    PubMed

    Wang, Rui-Long; Li, Jun; Staehelin, Christian; Xin, Xiao-Wei; Su, Yi-Juan; Zeng, Ren-Sen

    2015-01-01

    Cytochrome P450 monooxygenases (P450s) of insects are known to be involved in the metabolism or detoxification of plant allelochemicals and insecticides. Spodoptera litura (Lepidoptera, Noctuidae) is a polyphagous moth responsible for severe yield losses in many crops. In this study, two full-length P450 genes, CYP6B48 and CYP6B58, were cloned from S. litura. The cDNA sequences encode proteins with 503 and 504 amino acids, respectively. Phylogenetic analysis revealed that CYP6B48 and CYP6B58 belong to the CYP6B subfamily of P450s. Quantitative real-time PCR analyses showed that CYP6B48 and CYP6B58 were expressed only at larval stage, but not at pupal and adult stages. The highest levels of transcripts were found in the midguts and fat bodies of the larvae. No expression was detected in the ovary or hemolymph. Feeding with diets containing cinnamic acid, quercetin, or coumarin did not affect expression of CYP6B48. In contrast, diet supplemented with xanthotoxin dramatically increased the levels of CYP6B48 transcript in the midgut and fat bodies. Larvae fed with flavone had high levels of transcript of CYP6B48 in the midgut, whereas only slightly elevated levels were found in the fat bodies. Effects of the tested allelochemicals on CYP6B58 expression were minor. Hence, our findings show that S. litura responds to specific allelochemicals such as xanthotoxin with the accumulation of CYP6B48 transcripts, suggesting that specific signals in the food control the insect's ability to convert toxic allelochemicals to less harmful forms at the transcriptional level.

  9. Down-regulation of a chitin synthase a gene by RNA interference enhances pathogenicity of Beauveria bassiana ANU1 against Spodoptera exigua (HÜBNER).

    PubMed

    Lee, Jung-Bok; Kim, Hyun Soo; Park, Youngjin

    2017-02-01

    Chitin synthase (CHS) is an important enzymatic component, which is required for chitin formation in the cuticles and cuticular linings of other tissues in insects. CHSs have been divided into two classes, classes A and B, based on their amino acid sequence similarities and functions. Class A CHS (CHS-A) is specifically expressed in the epidermis and related ectodermal cells such as tracheal cells, while class B CHS (CHS-B) is expressed in gut epithelial cells that produce peritrophic matrices. In this study, we cloned the CHS-A gene from the beet armyworm, Spodoptera exigua (SeCHS-A). The SeCHS-A contains an open reading frame of 4,698 nucleotides, encoding a protein of 1,565 amino acids with a predicted molecular mass of approximately 177.8 kDa. The SeCHS-A mRNA was expressed in all developmental stages and specifically in the epidermis and tracheae tissue by quantitative real-time-PCR analysis. Expression of SeCHS-A gene was suppressed by feeding double-stranded RNA (dsCHS-A, 400 ng/larva) in the third instar larvae of S. exigua. Suppression of the SeCHS-A gene expression significantly increased 35% of mortality on pupation of S. exigua. Also, the third instar larvae fed with dsCHS-A significantly increased susceptibility to entomopathogenic fungi, Beauveria bassiana ANU1 at 3 days after treatment. These results suggest that the SeCHS-A gene plays an important role in development of S. exigua and RNA interference may apply to effective pest control with B. bassiana.

  10. Salt-tolerant and -sensitive alfalfa (Medicago sativa) cultivars have large variations in defense responses to the lepidopteran insect Spodoptera litura under normal and salt stress condition

    PubMed Central

    Lei, Yunting; Liu, Qing; Hettenhausen, Christian; Cao, Guoyan; Tan, Qing; Zhao, Weiye; Lin, Honghui

    2017-01-01

    In nature, plants are often exposed to multiple stress factors at the same time. Yet, little is known about how plants modulate their physiology to counteract simultaneous abiotic and biotic stresses, such as soil salinity and insect herbivory. In this study, insect performance bioassays, phytohormone measurements, quantification of transcripts, and protein determination were employed to study the phenotypic variations of two alfalfa (Medicago sativa) cultivars in response to insect Spodoptera litura feeding under normal and salt stress condition. When being cultivated in normal soil, the salt-tolerant alfalfa cultivar Zhongmu-1 exhibited lower insect resistance than did the salt-sensitive cultivar Xinjiang Daye. Under salinity stress, the defense responses of Xinjiang Daye were repressed, whereas Zhongmu-1 did not show changes in resistance levels. It is likely that salinity influenced the resistance of Xinjiang Daye through suppressing the accumulation of jasmonic acid-isoleucine (JA-Ile), which is the bioactive hormone inducing herbivore defense responses, leading to attenuated trypsin proteinase inhibitor (TPI) activity. Furthermore, exogenous ABA supplementation suppressed the insect herbivory-induced JA/JA-Ile accumulation and levels of JAR1 (jasmonate resistant 1) and TPI, and further decreased the resistance of Xinjiang Daye, whereas Zhongmu-1 showed very little response to the increased ABA level. We propose a mechanism, in which high levels of abscisic acid induced by salt treatment may affect the expression levels of JAR1 and consequently decrease JA-Ile accumulation and thus partly suppress the defense of Xinjiang Daye against insects under salt stress. This study provides new insight into the mechanism by which alfalfa responds to concurrent abiotic and biotic stresses. PMID:28719628

  11. Salt-tolerant and -sensitive alfalfa (Medicago sativa) cultivars have large variations in defense responses to the lepidopteran insect Spodoptera litura under normal and salt stress condition.

    PubMed

    Lei, Yunting; Liu, Qing; Hettenhausen, Christian; Cao, Guoyan; Tan, Qing; Zhao, Weiye; Lin, Honghui; Wu, Jianqiang

    2017-01-01

    In nature, plants are often exposed to multiple stress factors at the same time. Yet, little is known about how plants modulate their physiology to counteract simultaneous abiotic and biotic stresses, such as soil salinity and insect herbivory. In this study, insect performance bioassays, phytohormone measurements, quantification of transcripts, and protein determination were employed to study the phenotypic variations of two alfalfa (Medicago sativa) cultivars in response to insect Spodoptera litura feeding under normal and salt stress condition. When being cultivated in normal soil, the salt-tolerant alfalfa cultivar Zhongmu-1 exhibited lower insect resistance than did the salt-sensitive cultivar Xinjiang Daye. Under salinity stress, the defense responses of Xinjiang Daye were repressed, whereas Zhongmu-1 did not show changes in resistance levels. It is likely that salinity influenced the resistance of Xinjiang Daye through suppressing the accumulation of jasmonic acid-isoleucine (JA-Ile), which is the bioactive hormone inducing herbivore defense responses, leading to attenuated trypsin proteinase inhibitor (TPI) activity. Furthermore, exogenous ABA supplementation suppressed the insect herbivory-induced JA/JA-Ile accumulation and levels of JAR1 (jasmonate resistant 1) and TPI, and further decreased the resistance of Xinjiang Daye, whereas Zhongmu-1 showed very little response to the increased ABA level. We propose a mechanism, in which high levels of abscisic acid induced by salt treatment may affect the expression levels of JAR1 and consequently decrease JA-Ile accumulation and thus partly suppress the defense of Xinjiang Daye against insects under salt stress. This study provides new insight into the mechanism by which alfalfa responds to concurrent abiotic and biotic stresses.

  12. Strong oviposition preference for Bt over non-Bt maize in Spodoptera frugiperda and its implications for the evolution of resistance.

    PubMed

    Téllez-Rodríguez, Pilar; Raymond, Ben; Morán-Bertot, Ivis; Rodríguez-Cabrera, Lianet; Wright, Denis J; Borroto, Carlos G; Ayra-Pardo, Camilo

    2014-06-16

    Transgenic crops expressing Bt toxins have substantial benefits for growers in terms of reduced synthetic insecticide inputs, area-wide pest management and yield. This valuable technology depends upon delaying the evolution of resistance. The 'high dose/refuge strategy', in which a refuge of non-Bt plants is planted in close proximity to the Bt crop, is the foundation of most existing resistance management. Most theoretical analyses of the high dose/refuge strategy assume random oviposition across refugia and Bt crops. In this study we examined oviposition and survival of Spodoptera frugiperda across conventional and Bt maize and explored the impact of oviposition behavior on the evolution of resistance in simulation models. Over six growing seasons oviposition rates per plant were higher in Bt crops than in refugia. The Cry1F Bt maize variety retained largely undamaged leaves, and oviposition preference was correlated with the level of feeding damage in the refuge. In simulation models, damage-avoiding oviposition accelerated the evolution of resistance and either led to requirements for larger refugia or undermined resistance management altogether. Since larval densities affected oviposition preferences, pest population dynamics affected resistance evolution: larger refugia were weakly beneficial for resistance management if they increased pest population sizes and the concomitant degree of leaf damage. Damaged host plants have reduced attractiveness to many insect pests, and crops expressing Bt toxins are generally less damaged than conventional counterparts. Resistance management strategies should take account of this behavior, as it has the potential to undermine the effectiveness of existing practice, especially in the tropics where many pests are polyvoltinous. Efforts to bring down total pest population sizes and/or increase the attractiveness of damaged conventional plants will have substantial benefits for slowing the evolution of resistance.

  13. Comprehensive Analysis of Gene Expression Profiles of the Beet Armyworm Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Vip3Aa Toxin

    PubMed Central

    Bel, Yolanda; Jakubowska, Agata K.; Costa, Juliana; Herrero, Salvador; Escriche, Baltasar

    2013-01-01

    Host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. Vip proteins, which are Bacillus thuringensis (Bt) insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. This new group of Bt proteins represents an interesting alternative to the classical Bt Cry toxins because current data suggests that they do not share the same mode of action. We have designed and developed a genome-wide microarray for the beet armyworm Spodoptera exigua, a serious lepidopteran pest of many agricultural crops, and used it to better understand how lepidopteran larvae respond to the treatment with the insecticidal protein Vip3Aa. With this approach, the goal of our study was to evaluate the changes in gene expression levels caused by treatment with sublethal doses of Vip3Aa (causing 99% growth inhibition) at 8 and 24 h after feeding. Results indicated that the toxin provoked a wide transcriptional response, with 19% of the microarray unigenes responding significantly to treatment. The number of up- and down-regulated unigenes was very similar. The number of genes whose expression was regulated at 8 h was similar to the number of genes whose expression was regulated after 24 h of treatment. The up-regulated sequences were enriched for genes involved in innate immune response and in pathogen response such as antimicrobial peptides (AMPs) and repat genes. The down-regulated sequences were mainly unigenes with homology to genes involved in metabolism. Genes related to the mode of action of Bt Cry proteins were found, in general, to be slightly overexpressed. The present study is the first genome-wide analysis of the response of lepidopteran insects to Vip3Aa intoxication. An insight into the molecular mechanisms and components related to Vip intoxication will allow designing of more effective management strategies for pest control. PMID:24312604

  14. Evidence of field-evolved resistance of Spodoptera frugiperda to Bt corn expressing Cry1F in Brazil that is still sensitive to modified Bt toxins.

    PubMed

    Monnerat, Rose; Martins, Erica; Macedo, Cristina; Queiroz, Paulo; Praça, Lilian; Soares, Carlos Marcelo; Moreira, Helio; Grisi, Isabella; Silva, Joseane; Soberon, Mario; Bravo, Alejandra

    2015-01-01

    Brazil ranked second only to the United States in hectares planted to genetically modified crops in 2013. Recently corn producers in the Cerrado region reported that the control of Spodoptera frugiperda with Bt corn expressing Cry1Fa has decreased, forcing them to use chemicals to reduce the damage caused by this insect pest. A colony of S. frugiperda was established from individuals collected in 2013 from Cry1Fa corn plants (SfBt) in Brazil and shown to have at least more than ten-fold higher resistance levels compared with a susceptible colony (Sflab). Laboratory assays on corn leaves showed that in contrast to SfLab population, the SfBt larvae were able to survive by feeding on Cry1Fa corn leaves. The SfBt population was maintained without selection for eight generations and shown to maintain high levels of resistance to Cry1Fa toxin. SfBt showed higher cross-resistance to Cry1Aa than to Cry1Ab or Cry1Ac toxins. As previously reported, Cry1A toxins competed the binding of Cry1Fa to brush border membrane vesicles (BBMV) from SfLab insects, explaining cross-resistance to Cry1A toxins. In contrast Cry2A toxins did not compete Cry1Fa binding to SfLab-BBMV and no cross-resistance to Cry2A was observed, although Cry2A toxins show low toxicity to S. frugiperda. Bioassays with Cry1AbMod and Cry1AcMod show that they are highly active against both the SfLab and the SfBt populations. The bioassay data reported here show that insects collected from Cry1Fa corn in the Cerrado region were resistant to Cry1Fa suggesting that resistance contributed to field failures of Cry1Fa corn to control S. frugiperda.

  15. Pretreated Glehnia littoralis Extract Prevents Neuronal Death Following Transient Global Cerebral Ischemia through Increases of Superoxide Dismutase 1 and Brain-derived Neurotrophic Factor Expressions in the Gerbil Hippocampal Cornu Ammonis 1 Area

    PubMed Central

    Park, Joon Ha; Lee, Tae-Kyeong; Yan, Bing-Chun; Shin, Bich-Na; Ahn, Ji Hyeon; Kim, In Hye; Cho, Jeong Hwi; Lee, Jae-Chul; Hwang, In Koo; Kim, Jong Dai; Hong, Seongkweon; Lee, Young Joo; Won, Moo-Ho; Kang, Il Jun

    2017-01-01

    Background: Glehnia littoralis, as a traditional herbal medicine to heal various health ailments in East Asia, displays various therapeutic properties including antioxidant effects. However, neuroprotective effects of G. littoralis against cerebral ischemic insults have not yet been addressed. Therefore, in this study, we first examined its neuroprotective effects in the hippocampus using a gerbil model of transient global cerebral ischemia (TGCI). Methods: Gerbils were subjected to TGCI for 5 min. G. littoralis extract (GLE; 100 and 200 mg/kg) was administrated orally once daily for 7 days before ischemic surgery. Neuroprotection was examined by neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. Gliosis was observed by immunohistochemistry for glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1. For neuroprotective mechanisms, immunohistochemistry for superoxide dismutase (SOD) 1 and brain-derived neurotrophic factor (BDNF) was done. Results: Pretreatment with 200 mg/kg of GLE protected pyramidal neurons in the cornu ammonis 1 (CA1) area from ischemic insult area (F = 29.770, P < 0.05) and significantly inhibited activations of astrocytes (F = 22.959, P < 0.05) and microglia (F = 44.135, P < 0.05) in the ischemic CA1 area. In addition, pretreatment with GLE significantly increased expressions of SOD1 (F = 28.561, P < 0.05) and BDNF (F = 55.298, P < 0.05) in CA1 pyramidal neurons of the sham- and ischemia-operated groups. Conclusions: Our findings indicate that pretreatment with GLE can protect neurons from ischemic insults, and we suggest that its neuroprotective mechanism may be closely associated with increases of SOD1 and BDNF expressions as well as attenuation of glial activation. PMID:28748852

  16. Phenrica littoralis (Bechyné, 1955) (Coleoptera: Chrysomelidae) a potential candidate for the biological control of alligator weed, Alternantheraphiloxeroides (Martius) Grisebach (Amaranthaceae): redescription of the adult, first description of immature stages, and biological notes.

    PubMed

    Cabrera, Nora; Sosa, Alejandro J; Julien, Mic

    2013-01-01

    Flea beetles of alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay, and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby, Systena Chevrolat and Phenrica Bechyné were frequently found on this weed. Phenrica littoralis (Bechyn6) was the most abundant within this genus. The male is described and the holotype female is redescribed adding new diagnostic characters of the mouthparts, hind wings, metendosternite, and male and female genitalia. Larva and pupa are described and illustrated for the first time providing data for future phylogenetic studies in the subtribe Disonychina.

  17. EPA OIG's RSS Feed

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  18. Ectopic Expression of Aeluropus littoralis Plasma Membrane Protein Gene AlTMP1 Confers Abiotic Stress Tolerance in Transgenic Tobacco by Improving Water Status and Cation Homeostasis.

    PubMed

    Ben Romdhane, Walid; Ben-Saad, Rania; Meynard, Donaldo; Verdeil, Jean-Luc; Azaza, Jalel; Zouari, Nabil; Fki, Lotfi; Guiderdoni, Emmanuel; Al-Doss, Abdullah; Hassairi, Afif

    2017-03-24

    We report here the isolation and functional analysis of AlTMP1 gene encoding a member of the PMP3 protein family. In Aeluropus littoralis, AlTMP1 is highly induced by abscisic acid (ABA), cold, salt, and osmotic stresses. Transgenic tobacco expressing AlTMP1 exhibited enhanced tolerance to salt, osmotic, H₂O₂, heat and freezing stresses at the seedling stage. Under greenhouse conditions, the transgenic plants showed a higher level of tolerance to drought than to salinity. Noteworthy, AlTMP1 plants yielded two- and five-fold more seeds than non-transgenic plants (NT) under salt and drought stresses, respectively. The leaves of AlTMP1 plants accumulated lower Na⁺ but higher K⁺ and Ca(2+) than those of NT plants. Tolerance to osmotic and salt stresses was associated with higher membrane stability, low electrolyte leakage, and improved water status. Finally, accumulation of AlTMP1 in tobacco altered the regulation of some stress-related genes in either a positive (NHX1, CAT1, APX1, and DREB1A) or negative (HKT1 and KT1) manner that could be related to the observed tolerance. These results suggest that AlTMP1 confers stress tolerance in tobacco through maintenance of ion homeostasis, increased membrane integrity, and water status. The observed tolerance may be due to a direct or indirect effect of AlTMP1 on the expression of stress-related genes which could stimulate an adaptive potential not present in NT plants.

  19. Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis).

    PubMed

    Funk, W Chris; Lovich, Robert E; Hohenlohe, Paul A; Hofman, Courtney A; Morrison, Scott A; Sillett, T Scott; Ghalambor, Cameron K; Maldonado, Jesus E; Rick, Torben C; Day, Mitch D; Polato, Nicholas R; Fitzpatrick, Sarah W; Coonan, Timothy J; Crooks, Kevin R; Dillon, Adam; Garcelon, David K; King, Julie L; Boser, Christina L; Gould, Nicholas; Andelt, William F

    2016-05-01

    The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction-site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1-89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome-wide divergence. Nonetheless, outlier tests identified 3.6-6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential. © 2016 John Wiley & Sons Ltd.

  20. Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis)

    PubMed Central

    FUNK, W. CHRIS; LOVICH, ROBERT E.; HOHENLOHE, PAUL A.; HOFMAN, COURTNEY A.; MORRISON, SCOTT A.; SILLETT, T. SCOTT; GHALAMBOR, CAMERON K.; MALDONADO, JESUS E.; RICK, TORBEN C.; DAY, MITCH D.; POLATO, NICHOLAS R.; FITZPATRICK, SARAH W.; COONAN, TIMOTHY J.; CROOKS, KEVIN R.; DILLON, ADAM; GARCELON, DAVID K.; KING, JULIE L.; BOSER, CHRISTINA L.; GOULD, NICHOLAS; ANDELT, WILLIAM F.

    2016-01-01

    The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of 6 subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction-site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland gray foxes, and vice versa, indicating genetic drift drives genome-wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness, and reduced adaptive potential. PMID:26992010

  1. Ectopic Expression of Aeluropus littoralis Plasma Membrane Protein Gene AlTMP1 Confers Abiotic Stress Tolerance in Transgenic Tobacco by Improving Water Status and Cation Homeostasis

    PubMed Central

    Ben Romdhane, Walid; Ben-Saad, Rania; Meynard, Donaldo; Verdeil, Jean-Luc; Azaza, Jalel; Zouari, Nabil; Fki, Lotfi; Guiderdoni, Emmanuel; Al-Doss, Abdullah; Hassairi, Afif

    2017-01-01

    We report here the isolation and functional analysis of AlTMP1 gene encoding a member of the PMP3 protein family. In Aeluropus littoralis, AlTMP1 is highly induced by abscisic acid (ABA), cold, salt, and osmotic stresses. Transgenic tobacco expressing AlTMP1 exhibited enhanced tolerance to salt, osmotic, H2O2, heat and freezing stresses at the seedling stage. Under greenhouse conditions, the transgenic plants showed a higher level of tolerance to drought than to salinity. Noteworthy, AlTMP1 plants yielded two- and five-fold more seeds than non-transgenic plants (NT) under salt and drought stresses, respectively. The leaves of AlTMP1 plants accumulated lower Na+ but higher K+ and Ca2+ than those of NT plants. Tolerance to osmotic and salt stresses was associated with higher membrane stability, low electrolyte leakage, and improved water status. Finally, accumulation of AlTMP1 in tobacco altered the regulation of some stress-related genes in either a positive (NHX1, CAT1, APX1, and DREB1A) or negative (HKT1 and KT1) manner that could be related to the observed tolerance. These results suggest that AlTMP1 confers stress tolerance in tobacco through maintenance of ion homeostasis, increased membrane integrity, and water status. The observed tolerance may be due to a direct or indirect effect of AlTMP1 on the expression of stress-related genes which could stimulate an adaptive potential not present in NT plants. PMID:28338609

  2. [Effects of adult feeding on the reproduction and longevity of Noctuidae, Crambidae, Tortricidae and Elachistidae species].

    PubMed

    Milano, Patrícia; Berti Filho, Evoneo; Parra, José R P; Oda, Melissa L; Cônsoli, Fernando L

    2010-01-01

    This research evaluates the effect of the adult diet on the reproduction of Anticarsia gemmatalis Hübner, Heliothis virescens (Fabr.), Spodoptera frugiperda (J. E. Smith) (Noctuidae), Diatraea saccharalis (Fabr.) (Crambidae), Gymnandrosoma aurantianum Lima (Tortricidae) and Stenoma catenifer Walsingham (Elachistidae). Adults of all species were fed either water or a 10% honey solution. The egg viability for the 1st and 2nd egg masses, adult fecundity, longevity, number of mating and the ovigeny index (OI) (degree of ovarian maturation) were evaluated. Fecundity of A. gemmatalis and H. virescens was drastically reduced when females were fed only on water. Egg viability from both 1st and 2nd egg masses was variable between treatments. Females of A. gemmatalis, H. virescens and S. frugiperda, and males of some species had a reduced longevity when fed only on water. The number of matings was higher for A. gemmatalis and D. saccharalis when fed on water only. The OI was < 1.0 for all species evaluated indicating that all females may develop new oocytes as they age. Based on the OI and the reduced fecundity of A. gemmatalis and H. virescens, one observes that adult feeding is important for the reproduction of both species, and the IO is not a good parameter to indicate such condition. Spodoptera frugiperda, G. aurantianum, D. saccharalis and S. catenifer do not require any source of carbohydrates as adults to sustain their reproduction.

  3. Identification and localization of two sensory neuron membrane proteins from Spodoptera litura (Lepidoptera: Noctuidae).

    PubMed

    Zhang, Jin; Liu, Yang; Walker, William B; Dong, Shuang-Lin; Wang, Gui-Rong

    2015-03-01

    Sensory neuron membrane proteins (SNMPs), which are located on the dendritic membrane of olfactory sensory neurons (OSNs), are proposed to be associated with odor reception in insects. Recent studies have demonstrated that SNMP1 is essential for electrophysiological responses of OSNs to the sex pheromone, cis-vaccenyl acetate (cVA) in Drosophila melanogaster. To investigate the function of Lepidoptera SNMPs, we cloned two SNMP genes, SlituSNMP1 and SltiuSNMP2, from Spodoptera litura (Lepidoptera: Noctuidae). Sequence alignment and phylogenetic analysis showed that both genes bear the general characteristics of SNMPs, including six conserved cysteine residues and two transmembrane domains. Further expression profile experiments showed that SlituSNMP1 is mainly expressed in the antenna, while SlituSNMP2 is broadly expressed in various tissues. By in situ hybridization experiments, it was found that SlituSNMP1 expressing cells are surrounded by the SlituSNMP2 expressing cells in the pheromone sensitive sensilla, suggesting different functions of the two SNMPs in insect olfaction. © 2014 Institute of Zoology, Chinese Academy of Sciences.

  4. Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera: Noctuidae)

    PubMed Central

    Baskar, Kathirvelu; Muthu, Chellaiah; Raj, Gnanaprakasam Antony; Kingsley, Selvadurai; Ignacimuthu, Savarimuthu

    2012-01-01

    Objective To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura). Methods Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0% and 0.5% for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculated using probit analysis. Results Hexane crude extract showed maximum ovicidal activity of 61.94% at 5.0% concentration with a correlation value of r2=0.81, and least LC50 value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61% at 1 000 mg/kg with the LC50 value of 318.65 mg/kg and LC90 value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r2=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction. Conclusions As per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests. PMID:23593580

  5. Geographic Origin and Host Cultivar Influence on Digestive Physiology of Spodoptera exigua (Lepidoptera: Noctuidae) Larvae

    PubMed Central

    Golikhajeh, Neshat; Naseri, Bahram; Razmjou, Jabraeil

    2017-01-01

    Digestive enzymatic activity in three geographic strains (Miandiab, Kalposh and Moghan regions) of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) reared on different sugar beet cultivars (Dorothea, Rozier, Persia and Perimer) was studied under laboratory conditions (25 ± 1 °C, 65 ± 5% RH, and a photo period of 16:8 (L:D) h photoperiod). The results of this study demonstrated that digestive protease and amylase activity of S. exigua larvae was affected by both geographic origin of the pest and host plant cultivar. Three strains reared on the same sugar beet cultivars demonstrated different levels of proteolytic and amylolytic activities in fourth and fifth instars. The highest proteolytic and amylolytic activity, in most cases, was observed in larvae collected from Kalposh region. Among different sugar beet cultivars, the highest protease activity in three strains was observed on cultivars Rozier and Perimer. Nevertheless, the highest amylase activity was seen on cultivar Dorothea, and the lowest activity was seen on cultivar Rozier. This study suggested that variations in digestive enzymatic activity of three geographic strains of S. exigua might be attributed to local adaptation with their local host plant and environmental conditions inherent by larvae. PMID:28069730

  6. Effect of Host Age and Nematode Strain on Susceptibility of Spodoptera frugiperda to Steinernema feltiae

    PubMed Central

    Fuxa, James R.; Richter, Arthur R.; Acudelo-Silva, Fernando

    1988-01-01

    Median lethal concentrations (LC₅₀) were determined for four nematode populations (two strains of Steinernema feltiae, a S. feltiae hybrid, and S. bibionis) against fifth-instar fall armyworm (Spodoptera frugiperda) larvae and for the most virulent of these nematodes against different instars and stages of the insect. Based on lack of overlap of 95% fiducial limits, there were significant differences in virulence among the four nematodes. The LC₅₀ ranged from 7.6 to 33.3 nematodes/ 0.7 ml water, and slopes of the log dose-probit regression lines were similar except for the S. feltiae All strain. First-instar fall armyworms suffered virtually 100% mortality from the S. feltiae Mexican strain at 1.0 nematode/0.7 ml, and LC₅₀ were 2.3 and 7.9 nematodes/0.7 ml in third-instar and fifth-instar larvae, respectively. Pupae had 7-20% mortality at doses ranging from 30 to 60 nematodes/0.7 ml. PMID:19290189

  7. [BIO-INSECTICIDAL ACTIVITY OF ALPINIA GALANGA (L.) ON LARVAL DEVELOPMENT OF SPODOPTERA LITURA (LEPIDOPTERA: NOCTUIDAE).

    PubMed

    Pumchan, A; Puangsomchit, A; Temyarasilp, P; Pluempanupat, W; Bullangpoti, V

    2015-01-01

    The aim of the study was to assess the bio-efficacy of four Alpinia galanga rhizome crude extracts against the second and third instars of Spodoptera litura, an important field pest. The growth of younger larvae was significantly affected while that of the older larval stage was less influenced. In both stages, the methanol crude extract showed the greatest efficiency which caused the highest number of abnormal adults to occur and produced a large LD₅₀ value (12.816 µg/ larvae) pupicidal percentage after treatment, whereas, hexane extract caused the highest mortality during the larval-pupal stage after treatment with an LD₅₀ value of 6.354 µg/ larvae. However, the larval development was not significantly different among all treated larvae compared to the control. This study suggests that secondary larval instars of S. litura are more susceptible to the larval growth inhibitory action of Alpinia galanga extracts and these extracts could also be applied for use in the management of pests.

  8. Molecular characterization and expression of vitellogenin gene from Spodoptera exigua exposed to cadmium stress.

    PubMed

    Zhao, Jing; Sun, Yang; Xiao, Liubin; Tan, Yongan; Bai, Lixin

    2016-11-15

    In this study, we cloned a full-length cDNA encoding vitellogenin (Vg) in Spodoptera exigua. The complete Vg cDNA consists of 5694 nucleotides with a long open reading frame encoding 1761 amino acid residues. The deduced amino acid sequence shared high similarity with the Vgs of other lepidopteran insects, particularly in the C-terminal region including the GL/ICG motif, five cysteine residues and DGXR motif. We analyzed the spatiotemporal expression of Vg transcripts in S. exigua by RT-PCR and Real-time Quantitative PCR. The results revealed that Vg was expressed specifically in the female fat body and was detectable after 5th day female pupae. The maximum level of Vg mRNA appeared in 48-h-old female adults and started to decrease quickly. When exposed to cadmium (Cd) (25-100mg/kg), there was a significantly decreased Vg level in female adults. The information presented in this study suggested the Vg in S. exigua could be significantly affected by Cd pressure. Copyright © 2016. Published by Elsevier B.V.

  9. Susceptibility of Spodoptera frugiperda and S. exigua to Bacillus thuringiensis Vip3Aa insecticidal protein.

    PubMed

    Chakroun, Maissa; Bel, Yolanda; Caccia, Silvia; Abdelkefi-Mesrati, Lobna; Escriche, Baltasar; Ferré, Juan

    2012-07-01

    The Vip3Aa protein is an insecticidal protein secreted by Bacillus thuringiensis during the vegetative stage of growth. The activity of this protein has been tested after different steps/protocols of purification using Spodoptera frugiperda as a control insect. The results showed that the Vip3Aa protoxin was stable and retained full toxicity after being subjected to common biochemical steps used in protein purification. Bioassays with the protoxin in S. frugiperda and S. exigua showed pronounced differences in LC(50) values when mortality was measured at 7 vs. 10d. At 7d most live larvae were arrested in their development. LC(50) values of "functional mortality" (dead larvae plus larvae remaining in the first instar), measured at 7d, were similar or even lower than the LC(50) values of mortality at 10d. This strong growth inhibition was not observed when testing the trypsin-activated protein (62 kDa) in either species. S. exigua was less susceptible than S. frugiperda to the protoxin form, with LC(50) values around 10-fold higher. However, both species were equally susceptible to the trypsin-activated form. Processing of Vip3Aa protoxin to the activated form was faster with S. frugiperda midgut juice than with S. exigua midgut juice. The results strongly suggest that the differences in the rate of activation of the Vip3Aa protoxin between both species are the basis for the differences in susceptibility towards the protoxin form.

  10. Population Variation of the Fall Armyworm, Spodoptera frugiperda, in the Western Hemisphere

    PubMed Central

    Clark, Pete L.; Molina-Ochoa, Jaime; Martinelli, Samuel; Skoda, Steven R.; Isenhour, David J.; Lee, Donald J.; Krumm, Jeffrey T.; Foster, John E.

    2007-01-01

    Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), the fall armyworm is the most economically important maize pest in the western hemisphere. This research focused on the genetic variability of the maize host strain because there is a lack of information in this area of S. frugiperda research. Amplified fragment length polymorphism (AFLP) was used to assess the genetic variability of S. frugiperda over a large geographic area. Twenty populations were collected from the maize, one population was collected from princess tree, one population was collected from lemon tree, and one population was collected from bermudagrass. The 23 populations were from Mexico, the continental United States, Puerto Rico, Brazil, and Argentina. The objective of this research was to evaluate whether the majority of genetic variability was within populations or between populations. The AFLP results showed that the majority of the genetic variability is within populations and not between populations, indicating minor gene flow and suggesting that S. frugiperda in the Western Hemisphere are an interbreeding population. PMID:20334595

  11. Virulence of Entomopathogenic Fungi Metarhizium anisopliae and Paecilomyces fumosoroseus for the Microbial Control of Spodoptera exigua

    PubMed Central

    Han, Ji Hee; Jin, Byung Rae; Lee, Sang Yeob

    2014-01-01

    The beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) is difficult to control using chemical insecticides because of the development of insecticide resistance. Several pest control agents are used to control the beet armyworm. Entomopathogenic fungi are one of the candidates for eco-friendly pest control instead of chemical control agents. In this study, among various entomopathogenic fungal strains isolated from soil two isolates were selected as high virulence pathogens against larva of beet armyworm. Control efficacy of fungal conidia was influenced by conidia concentration, temperature, and relative humidity (RH). The isolates Metarhizium anisopliae FT83 showed 100% cumulative mortality against second instar larvae of S. exigua 3 days after treatment at 1 × 107 conidia/mL and Paecilomyces fumosoroseus FG340 caused 100% mortality 6 days after treatment at 1 × 104 conidia/mL. Both M. anisopliae FT83 and P. fumosoroseus FG340 effectively controlled the moth at 20~30℃. M. anisopliae FT83 was significantly affected mortality by RH: mortality was 86.7% at 85% RH and 13.4% at 45% RH. P. fumosoroseus FG340 showed high mortality as 90% at 45% RH and 100% at 75% RH 6 days after conidia treatments. These results suggest that P. fumosoroseus FG340 and M. anisopliae FT83 have high potential to develop as a biocontrol agent against the beet armyworm. PMID:25606011

  12. Antifeedant activity of an anthraquinone aldehyde in Galium aparine L. against Spodoptera litura F.

    PubMed

    Morimoto, Masanori; Tanimoto, Kumiko; Sakatani, Akiko; Komai, Koichiro

    2002-05-01

    The insect antifeedant anthraquinone aldehyde nordamnacanthal (1,3-dihydroxy-anthraquinone-2-al) was identified in Galium aparine L., and isolated from the root powder of akane (Rubia akane), a member of the Rubiaceae. Structure-activity relationship (SAR) studies using a series of anthraquinone analogues suggested that the aldehyde group on the anthraquinone was more important than the quinone moiety for antifeedant activity against the common cutworm (Spodoptera litura). High levels of nordamnacanthal were found in the seed leaf stage and in callus tissue induced from seedlings of G. aparine, but its concentration decreased with plant development. Since these compounds are natural pigments for dying textiles, we also evaluated the antifeedant activity against the carpet beetle (Attagenus japonicus ), a textile pest was also evaluated. While nordamnacanthal had strong antifeedant activity against the common cutworm, it did not show any antifeedant activity against the carpet beetle. The most effective antifeedant against the carpet beetle was the major constituent in the extract of R. trictorum, lucidin-3-O-primeveroside, a food pigment.

  13. Pre-exposures to taro (Colocasia esculenta) leaf volatiles enhance the reproductive behaviors in Spodoptera litura.

    PubMed

    Wan, Xinlong; Bai, Jiaxiu; Lu, Rui; Zhang, Daogen; Lin, Huiyue

    2017-03-20

    Plant volatiles serve as sensory cues for insects to find food and habitats. They are also reported to affect many insect behaviors. In the current study, we determined how exposures to taro (Colocasia esculenta) for 24h affect reproductive behaviors in Spodoptera litura. Further, we investigated the mechanisms that regulate taro volatiles-induced reproductive behavior in S. litura by recording peripheral, behavioral, and neuronal responses of male moths to sex pheromone components (Z9,E11-14:OAc and Z9,E12-14:OAc) and their mixtures in different ratios, as well as gene expression levels of sex pheromone receptors. The results showed that the exposure to taro volatiles significantly enhanced male mating rate, mating duration, and egg hatching rates, but not mating times and the number of oviposition per female. Consistently, the peripheral and behavioral responses of pre-exposed males to sex pheromone components and their mixtures wherein Z9,E11-14:OAc owned higher proportions, as well as neuronal responses to those at low dosages were significantly increased compared to non-exposed males. The expression levels of sex pheromone receptor genes were also significantly increased in pre-exposed males compared to non-exposed ones. These results suggest that taro volatile pre-exposures could promote the reproductive performance of S. litura by enhancing the competitiveness of male mating and communications between male and females. These findings provide new insights for the management of this insect pest as well as other moths.

  14. Identification and Expression Profiles of Sex Pheromone Biosynthesis and Transport Related Genes in Spodoptera litura

    PubMed Central

    Zhang, Ya-Nan; Zhu, Xiu-Yun; Fang, Li-Ping; He, Peng; Wang, Zhi-Qiang; Chen, Geng; Sun, Liang; Ye, Zhan-Feng; Deng, Dao-Gui; Li, Jin-Bu

    2015-01-01

    Although the general pathway of sex pheromone synthesis in moth species has been established, the molecular mechanisms remain poorly understood. The common cutworm Spodoptera litura is an important agricultural pest worldwide and causes huge economic losses annually. The female sex pheromone of S. litura comprises Z9,E11-14:OAc, Z9,E12-14:OAc, Z9-14:OAc, and E11-14:OAc. By sequencing and analyzing the transcriptomic data of the sex pheromone glands, we identified 94 candidate genes related to pheromone biosynthesis (55 genes) or chemoreception (39 genes). Gene expression patterns and phylogenetic analysis revealed that two desaturase genes (SlitDes5 and SlitDes11) and one fatty acyl reductase gene (SlitFAR3) showed pheromone gland (PG) biased or specific expression, and clustered with genes known to be involved in pheromone synthesis in other moth species. Furthermore, 4 chemoreception related genes (SlitOBP6, SlitOBP11, SlitCSP3, and SlitCSP14) also showed higher expression in the PG, and could be additional candidate genes involved in sex pheromone transport. This study provides the first solid background information that should facilitate further elucidation of sex pheromone biosynthesis and transport, and indicates potential targets to disrupt sexual communication in S. litura for a novel pest management strategy. PMID:26445454

  15. Synthetic pheromones and plant volatiles alter the expression of chemosensory genes in Spodoptera exigua

    PubMed Central

    Wan, Xinlong; Qian, Kai; Du, Yongjun

    2015-01-01

    Pheromone and plant odorants are important for insect mating, foraging food sources and oviposition. To understand the molecular mechanisms regulating pheromone and odorant signaling, we employed qRT-PCR to study the circadian rhythms of ABP, OBP, PBP, and OR gene expression in the beet armyworm, Spodoptera exigua and their responses after a pre-exposure to sex pheromone compounds or plant volatiles. The neuronal responses of male S. exigua to 20 chemical compounds were recorded at three specific time periods using the electroantennogram. The results showed a circadian rhythm in the expression profiles of some chemosensory genes in the antennae similar to their behavioral rhythm. The expression profiles of OR3, OR6, OR11, OR13, OR16, OR18, Orco, ABP2, OBP1, OBP7, and PBP1, and EAG responses to chemical compounds, as well as their circadian rhythm were significantly affected after exposure to synthetic sex pheromones and plant volatiles. These findings provide the first evidence that the gene expression of chemosensory genes and olfactory sensitivity to sex pheromones are affected by pre-exposing insects to pheromone compounds and plant volatiles. It helps to understand the molecular mechanisms underlying pheromone activity, and the application of sex pheromones and plant volatiles in mating disruption or mass trapping. PMID:26611815

  16. The complete sequence of the first Spodoptera frugiperda Betabaculovirus genome: a natural multiple recombinant virus.

    PubMed

    Cuartas, Paola E; Barrera, Gloria P; Belaich, Mariano N; Barreto, Emiliano; Ghiringhelli, Pablo D; Villamizar, Laura F

    2015-01-20

    Spodoptera frugiperda (Lepidoptera: Noctuidae) is a major pest in maize crops in Colombia, and affects several regions in America. A granulovirus isolated from S. frugiperda (SfGV VG008) has potential as an enhancer of insecticidal activity of previously described nucleopolyhedrovirus from the same insect species (SfMNPV). The SfGV VG008 genome was sequenced and analyzed showing circular double stranded DNA of 140,913 bp encoding 146 putative ORFs that include 37 Baculoviridae core genes, 88 shared with betabaculoviruses, two shared only with betabaculoviruses from Noctuide insects, two shared with alphabaculoviruses, three copies of own genes (paralogs) and the other 14 corresponding to unique genes without representation in the other baculovirus species. Particularly, the genome encodes for important virulence factors such as 4 chitinases and 2 enhancins. The sequence analysis revealed the existence of eight homologous regions (hrs) and also suggests processes of gene acquisition by horizontal transfer including the SfGV VG008 ORFs 046/047 (paralogs), 059, 089 and 099. The bioinformatics evidence indicates that the genome donors of mentioned genes could be alpha- and/or betabaculovirus species. The previous reported ability of SfGV VG008 to naturally co-infect the same host with other virus show a possible mechanism to capture genes and thus improve its fitness.

  17. Interaction between Calcium Ions and Bacillus thuringiensis Toxin Activity against Sf9 Cells (Spodoptera frugiperda, Lepidoptera)

    PubMed Central

    Monette, R.; Potvin, L.; Baines, D.; Laprade, R.; Schwartz, J. L.

    1997-01-01

    The effects of calcium ions and modulators of calcium movement on Bacillus thuringiensis insecticidal protein toxicity were investigated with Sf9 cells (Spodoptera frugiperda, fall armyworm) by a new B. thuringiensis toxicity assay based on measurement of fluorescence of ethidium homodimer, a high-affinity DNA stain. CryIC toxicity was substantially stimulated by extracellular calcium in a dose-dependent way (in the millimolar range), while toxicity enhancement could not be replicated when calcium was replaced by barium. This incremental toxicity was reduced by cobalt and lanthanum ions, two inorganic-calcium transport inhibitors. Methoxyverapamil, a voltage-dependent calcium channel blocker, and nifedipine, an inhibitor of dihydropyridine-sensitive L-type calcium channels, had no effect on CryIC toxin activity, but BAY K 8644, an L-type calcium channel activator, increased CryIC activity at high concentrations of extracellular calcium. While A23187, a calcium ionophore, and TMB-8, an inhibitor of intracellular-calcium mobilization, did not change CryIC-induced mortality, thapsigargin, an inhibitor of calcium uptake in intracellular stores, and more particularly trifluoperazine, which inhibits calcium-calmodulin-dependent processes, increased CryIC-mediated toxicity. The incremental effect of extracellular calcium on CryIC-induced toxicity was consistent with an increased concentration of intracellular calcium. PMID:16535509

  18. The Complete Sequence of the First Spodoptera frugiperda Betabaculovirus Genome: A Natural Multiple Recombinant Virus

    PubMed Central

    Cuartas, Paola E.; Barrera, Gloria P.; Belaich, Mariano N.; Barreto, Emiliano; Ghiringhelli, Pablo D.; Villamizar, Laura F.

    2015-01-01

    Spodoptera frugiperda (Lepidoptera: Noctuidae) is a major pest in maize crops in Colombia, and affects several regions in America. A granulovirus isolated from S. frugiperda (SfGV VG008) has potential as an enhancer of insecticidal activity of previously described nucleopolyhedrovirus from the same insect species (SfMNPV). The SfGV VG008 genome was sequenced and analyzed showing circular double stranded DNA of 140,913 bp encoding 146 putative ORFs that include 37 Baculoviridae core genes, 88 shared with betabaculoviruses, two shared only with betabaculoviruses from Noctuide insects, two shared with alphabaculoviruses, three copies of own genes (paralogs) and the other 14 corresponding to unique genes without representation in the other baculovirus species. Particularly, the genome encodes for important virulence factors such as 4 chitinases and 2 enhancins. The sequence analysis revealed the existence of eight homologous regions (hrs) and also suggests processes of gene acquisition by horizontal transfer including the SfGV VG008 ORFs 046/047 (paralogs), 059, 089 and 099. The bioinformatics evidence indicates that the genome donors of mentioned genes could be alpha- and/or betabaculovirus species. The previous reported ability of SfGV VG008 to naturally co-infect the same host with other virus show a possible mechanism to capture genes and thus improve its fitness. PMID:25609309

  19. General up regulation of Spodoptera frugiperda trypsins and chymotrypsins allows its adaptation to soybean proteinase inhibitor.

    PubMed

    Brioschi, Daniela; Nadalini, Larissa D; Bengtson, Mario H; Sogayar, Mari Cleide; Moura, Daniel S; Silva-Filho, Marcio C

    2007-12-01

    The existence of a diverse serine proteinase gene family in lepidopteran insects suggests they play a significant role in the insect adaptation to plant proteinase inhibitors. These proteinases have been shown to be involved in the process of proteolytic digestion in insect larvae. We carried out a selective transcriptome study of midguts from Spodoptera frugiperda larvae fed on a diet supplemented with soybean proteinase inhibitor (SPI). Using subtracted cDNA libraries made of gut-expressed transcripts, a total of 2100 partial sequences were obtained, of those 38% were related to digestive process. Two large and diverse groups of chymotrypsins and trypsins were obtained, and some of these proteinase-encoding genes were further characterized by quantitative RT-PCR. The transcription analyses revealed two groups: one group of genes constitutively expressed in the control larvae that is up regulated by introducing SPI to the diet, and a second group that is absent in the control but is induced by the SPI-rich diet. This observation suggests that adaptation of S. frugiperda to SPI involves de novo synthesis and also up regulation of existing enzymes. Proteases from intestines of larvae reared on a diet with SPI showed insensitivity to the inhibitor. The proteases were also insensitive to a broad-spectrum potato proteinase inhibitor preparation. We propose that adaptation of S. frugiperda to SPI follows a "shotgun" approach, based on a general up regulation of a large set of endoproteinases.

  20. Differential expression of chemosensory-protein genes in midguts in response to diet of Spodoptera litura.

    PubMed

    Yi, Xin; Qi, Jiangwei; Zhou, Xiaofan; Hu, Mei Ying; Zhong, Guo Hua

    2017-03-22

    While it has been well characterized that chemosensory receptors in guts of mammals have great influence on food preference, much remains elusive in insects. Insect chemosensory proteins (CSPs) are soluble proteins that could deliver chemicals to olfactory and gustatory receptors. Recent studies have identified a number of CSPs expressed in midgut in Lepidoptera insects, which started to reveal their roles in chemical recognition and stimulating appetite in midgut. In this study, we examined expression patterns in midgut of 21 Spodoptera litura CSPs (SlitCSPs) characterized from a previously reported transcriptome, and three CSPs were identified to be expressed highly in midgut. The orthologous relationships between midgut expressed CSPs in S. litura and those in Bombyx mori and Plutella xylostella also suggest a conserved pattern of CSP expression in midgut. We further demonstrated that the expression of midgut-CSPs may change in response to different host plants, and SlitCSPs could bind typical chemicals from host plant in vitro. Overall, our results suggested midgut expressed SlitCSPs may have functional roles, likely contributing to specialization and adaption to different ecosystems. Better knowledge of this critical component of the chemsensation signaling pathways in midguts may improve our understanding of food preference processes in a new perspective.

  1. Impact of elevated CO₂ on tobacco caterpillar, Spodoptera litura on peanut, Arachis hypogea.

    PubMed

    Srinivasa Rao, M; Manimanjari, D; Vanaja, M; Rama Rao, C A; Srinivas, K; Rao, V U M; Venkateswarlu, B

    2012-01-01

    If the carbon dioxide (CO(2)) concentration in the atmosphere changes in the future, as predicted, it could influence crops and insect pests. The growth and development of the tobacco caterpillar, Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera), reared on peanut (Arachis hypogea L.) foliage grown under elevated CO(2) (550 ppm and 700 ppm) concentrations in open top chambers at Central Research Institute for Dryland Agriculture, Hyderabad, India, were examined in this study. Significantly lower leaf nitrogen, higher carbon, higher relative proportion of carbon to nitrogen and higher polyphenols content expressed in terms of tannic acid equivalents were observed in the peanut foliage grown under elevated CO(2) levels. Substantial influence of elevated CO(2) on S. litura was noticed, such as longer larval duration, higher larval weights, and increased consumption of peanut foliage by S. litura larvae under elevated CO(2) compared with ambient CO(2). Relative consumption rate was significantly higher for S. litura larva fed plants grown at 550 and 700 ppm than for larvae fed plants grown at ambient condition. Decreased efficiency of conversion of ingested food, decreased efficiency of conversion of digested food, and decreased relative growth rate of larvae was observed under elevated CO(2). The present results indicate that elevated CO(2) levels altered the quality of the peanut foliage, resulting in higher consumption, lower digestive efficiency, slower growth, and longer time to pupation (one day more than ambient).

  2. Characterization of bro-a gene of Spodoptera litura multicapsid nucleopolyhedrovirus.

    PubMed

    Gong, Yingxue; Li, Zhaofei; Pan, Lijing; Yu, Mei; Yang, Kai; Pang, Yi

    2004-04-01

    Spodoptera litura multicapsid nucleopolyhedrovirus (SpltMNPV) ORF120 (designated as the bro-a gene) is a member of the unique multigene family called the baculovirus repeated ORFs (bro) family. Computer-assisted analysis revealed that BRO-A does not contain the conserved Bro-N domain in its N-terminus, but contains a single-stranded DNA binding motif near its C-terminus. Transcriptional analysis indicated that bro-a transcript initiated within a baculovirus consensus early start site motif (ATCAGT). In vitro the bro-a gene transcript was present at 12 h post infection (p.i.) and remained detectable up to 96 h p.i. Western blot analysis of BRO-A expression in SpltMNPV infected S. litura cells showed that it was present from 72 h to 96 h p.i. in vitro. Analysis of extracts from nuclear structures indicated that BRO-A could not be extracted with DNA or proteins which bind to DNA.

  3. Characterization of bro-b gene of Spodoptera litura multicapsid nucleopolyhedrovirus.

    PubMed

    Gong, Yingxue; Li, Zhaofei; Wang, Lihua; Pan, Lijing; Yang, Kai; Pang, Yi

    2003-10-01

    Spodoptera litura multicapsid nucleopolyhedrovirus (SpltMNPV) ORF125 (designated as the bro-b gene) is a member of the unique multigene family called the baculovirus repeated ORFs (bro) family. Computer-assisted analysis revealed that BRO-B contains a conserved Bro-N domain in its N-terminus and a single-stranded DNA (ssDNA) binding motif in the middle region. In vitro the bro-b gene transcription was present at 12 h post-infection (p.i.) and remained detectable up to 96 h p.i. Western blot analysis of BRO-B expression with an antiserum made against 6xHis tagged BRO-B expressed in Escherichia coli showed that it was present from 12 h through 96 h p.i. in vitro. Structural localization revealed that BRO-B could be found in the nucleocapsid components of both occlusion-derived virus (ODV) and budded virus (BV). Immunofluorescence analysis indicated that BRO-B is located only in the nucleus of infected S. litura cells. Furthermore, Western blot analysis indicated that BRO-B was associated with nuclear structures. These results suggested that BRO-B might be a nuclear-associated protein.

  4. Potential of trap crops for integrated management of the tropical armyworm, Spodoptera litura in tobacco.

    PubMed

    Zhou, Zhongshi; Chen, Zepeng; Xu, Zaifu

    2010-01-01

    The tropical armyworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae), is an important pest of tobacco, Nicotiana tabacum L. (Solanales: Solanaceae), in South China that is becoming increasingly resistant to pesticides. Six potential trap crops were evaluated to control S. litura on tobacco. Castor bean, Ricinus communis L. (Malpighiales: Euphorbiaceae), and taro, Colocasia esculenta (L.) Schott (Alismatales: Araceae), hosted significantly more S. litura than peanut, Arachis hypogaea L. (Fabales: Fabaceae), sweet potato, Ipomoea batata Lam. (Solanales: Convolvulaceae) or tobacoo in a greenhouse trial, and tobacco field plots with taro rows hosted significantly fewer S. litura than those with rows of other trap crops or without trap crops, provided the taro was in a fast-growing stage. When these crops were grown along with eggplant, Solanum melongena L. (Solanales: Solanaceae), and soybean, Glycines max L. (Fabales: Fabaceae), in separate plots in a randomized matrix, tobacco plots hosted more S. litura than the other crop plots early in the season, but late in the season, taro plots hosted significantly more S. litura than tobacco, soybean, sweet potato, peanut or eggplant plots. In addition, higher rates of S. litura parasitism by Microplitis prodeniae Rao and Chandry (Hymenoptera: Bracondidae) and Campoletis chlorideae Uchida (Ichnumonidae) were observed in taro plots compared to other crop plots. Although taro was an effective trap crop for managing S. litura on tobacco, it did not attract S. litura in the seedling stage, indicating that taro should either be planted 20-30 days before tobacco, or alternative control methods should be employed during the seedling stage.

  5. A COMPREHENSIVE STUDY ON APOPTOSIS INDUCTION BY AZADIRACHTIN IN Spodoptera frugiperda CULTURED CELL LINE Sf9.

    PubMed

    Shu, Benshui; Wang, Wenxiang; Hu, Qingbo; Huang, Jingfei; Hu, Meiying; Zhong, Guohua

    2015-07-01

    The induction of apoptosis by azadirachtin, a well-known botanical tetranortriterpenoid isolated from the neem tree (Azadirachta indica A. Juss) and other members of the Meliaceae, was investigated in Spodoptera frugiperda cultured cell line (Sf9). Morphological changes in Sf9 cells treated by various concentrations of azadirachtin were observed at different times under light microscopy. Morphological and biochemical analysis indicated that Sf9 cells treated by 1.5 μg/mL azadirachtin showed typical morphological changes, which were indicative of apoptosis and a clear DNA ladder. The flow cytometry analysis showed the apoptosis rate reached a maximum value of 32.66% at 24 h with 1.5 μg/mL azadirachtin in Sf9 cells. The inhibition of Sf9 cell proliferation suggested that the effect of azadirachtin was dose dependent and the EC50 at 48 and 72 h was 2.727 × 10(-6) and 6.348 × 10(-9) μg/mL, respectively. The treatment of azadirachtin in Sf9 cells could significantly increase the activity of Sf caspase-1, but showed no effect on the activity of Topo I, suggesting that the apoptosis induced by azadirachtinin Sf9 cells is through caspase-dependent pathway. These results provided not only a series of morphological, biochemical, and toxicological comprehensive evidences for induction of apoptosis by azadirachtin, but also a reference model for screening insect cell apoptosis inducers from natural compounds.

  6. Functional analysis of Spodoptera frugiperda nucleopolyhedrovirus late expression factors in Sf9 cells.

    PubMed

    Berretta, Marcelo F; López, M Gabriela; Taboga, Oscar; Sciocco-Cap, Alicia; Romanowski, Víctor

    2013-02-01

    We used transient expression assays to assess the function of the baculovirus Spodoptera frugiperda M nucleopolyhedrovirus (SfMNPV) homologs of Autographa californica MNPV (AcMNPV) factors involved in late gene expression (lefs), in the Sf9 insect cell-line, which is permissive for both viruses. It is well-established that nineteen AcMNPV lefs support optimal levels of activity from a late promoter-reporter gene cassette in this assay. A subgroup of SfMNPV lefs predicted to function in transcription-specific events substituted the corresponding AcMNPV lefs very efficiently. When all SfMNPV lefs were assayed, including replication lefs, activity was low, but addition of two AcMNPV lefs not encoded in SfMNPV genome, resulted in augmented reporter activity. SfMNPV IE-1 was able to activate an early promoter cis-linked to an hr-derived element from SfMNPV but not from AcMNPV. However, the level of early promoter activation with SfMNPV IE-1 was lower compared to AcMNPV IE-1.

  7. Insecticidal activity of two proteases against Spodoptera frugiperda larvae infected with recombinant baculoviruses

    PubMed Central

    2010-01-01

    Background Baculovirus comprise the largest group of insect viruses most studied worldwide, mainly because they efficiently kill agricutural insect pests. In this study, two recombinant baculoviruses containing the ScathL gene from Sarcophaga peregrina (vSynScathL), and the Keratinase gene from the fungus Aspergillus fumigatus (vSynKerat), were constructed. and their insecticidal properties analysed against Spodoptera frugiperda larvae. Results Bioassays of third-instar and neonate S. frugiperda larvae with vSynScathL and vSynKerat showed a decrease in the time needed to kill the infected insects when compared to the wild type virus. We have also shown that both recombinants were able to increase phenoloxidase activity in the hemolymph of S. frugiperda larvae. The expression of proteases in infected larvae resulted in destruction of internal tissues late in infection, which could be the reason for the increased viral speed of kill. Conclusions Baculoviruses and their recombinant forms constitute viable alternatives to chemical insecticides. Recombinant baculoviruses containing protease genes can be added to the list of engineered baculoviruses with great potential to be used in integrated pest management programs. PMID:20587066

  8. Impact of Elevated CO2 on Tobacco Caterpillar, Spodoptera litura on Peanut, Arachis hypogea

    PubMed Central

    Srinivasa Rao, M; Manimanjari, D; Vanaja, M; Rama Rao, CA; Srinivas, K; Rao, Vum; Venkateswarlu, B

    2012-01-01

    If the carbon dioxide (CO2) concentration in the atmosphere changes in the future, as predicted, it could influence crops and insect pests. The growth and development of the tobacco caterpillar, Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera), reared on peanut (Arachis hypogea L.) foliage grown under elevated CO2 (550 ppm and 700 ppm) concentrations in open top chambers at Central Research Institute for Dryland Agriculture, Hyderabad, India, were examined in this study. Significantly lower leaf nitrogen, higher carbon, higher relative proportion of carbon to nitrogen and higher polyphenols content expressed in terms of tannic acid equivalents were observed in the peanut foliage grown under elevated CO2 levels. Substantial influence of elevated CO2 on S. litura was noticed, such as longer larval duration, higher larval weights, and increased consumption of peanut foliage by S. litura larvae under elevated CO2 compared with ambient CO2. Relative consumption rate was significantly higher for S. litura larva fed plants grown at 550 and 700 ppm than for larvae fed plants grown at ambient condition. Decreased efficiency of conversion of ingested food, decreased efficiency of conversion of digested food, and decreased relative growth rate of larvae was observed under elevated CO2. The present results indicate that elevated CO2 levels altered the quality of the peanut foliage, resulting in higher consumption, lower digestive efficiency, slower growth, and longer time to pupation (one day more than ambient). PMID:23437971

  9. Molecular cloning, expression pattern and comparative analysis of chitin synthase gene B in Spodoptera exigua.

    PubMed

    Kumar, N Senthil; Tang, Bin; Chen, Xiaofei; Tian, Honggang; Zhang, Wenqing

    2008-03-01

    The chitin synthase (CHS) gene B (4781 bp) of Spodoptera exigua (SeCHSB) was cloned by reverse-transcription PCR (RT-PCR) and 3'/5' RACE from the midgut. SeCHSB contains an open reading frame of 4572 nucleotides, encoding a protein of 1523 amino acids with a predicted molecular mass of approximately 174.6 kDa. Alignment of SeCHSB with class B CHSs of other insects showed a high degree of conservation in the putative catalytic domain region. The structure of the SeCHSB gene was analyzed and was found to be the same as that of Manduca sexta CHSB (MsCHSB), including 23 exons and 22 introns but without alternative exons. Southern blot analysis revealed that SeCHSB was a single copy gene and the presence of only two chitin synthase genes in S. exigua. Further investigation indicated that SeCHSB was specifically expressed in the midgut, and its transcript existed constitutively in the midgut from the 3rd instar larval stage to prepupae and reached highest expression on the 1st day of the fifth instar larval stage. These data suggest that SeCHSB is very important in midgut formation and development. Chitin synthase gene comparisons between different classes of insects using software tools revealed some interesting aspects of the similarity and divergence of the gene in the Class Insecta.

  10. Fitness costs and stability of Cry1Fa resistance in Brazilian populations of Spodoptera frugiperda.

    PubMed

    Santos-Amaya, Oscar F; Tavares, Clébson S; Rodrigues, João Victor C; Campos, Silverio O; Guedes, Raul Narciso C; Alves, Analiza P; Pereira, Eliseu José G

    2017-01-01

    The presence of fitness costs of resistance to Bacillus thuringiensis (Bt) insecticidal proteins in insect populations may delay or even reverse the local selection of insect resistance to Bt transgenic crops, and deserves rigorous investigation. Here we assessed the fitness costs associated with Cry1Fa resistance in two strains of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), derived from field collections in different Brazilian regions and further selected in the laboratory for high levels of resistance to Cry1Fa using leaves of TC1507 corn. Fitness components were compared using paired resistant and susceptible strains with similar genetic backgrounds and F1 generations from reciprocal crosses, all of them reared on non-transgenic corn leaves. No apparent life history costs in the larval stage were observed in the Bt-resistant strains. Moreover, the resistance remained stable for seven generations in the absence of selection, with no decrease in the proportion of resistant individuals. Larval respiration rates were also similar between resistant and susceptible homozygotes, and heterozygotes displayed respiration rates and demographic performance equal or superior to those of susceptible homozygotes. In combination, these results indicate the lack of strong fitness costs associated with resistance to Cry1Fa in the fall armyworm strains studied. These findings suggest that Cry1Fa resistance in S. frugiperda populations is unlikely to be counterselected in Cry1Fa-free environments. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Frequency of Cry1F resistance alleles in Spodoptera frugiperda (Lepidoptera: Noctuidae) in Brazil.

    PubMed

    Farias, Juliano R; Andow, David A; Horikoshi, Renato J; Bernardi, Daniel; Ribeiro, Rebeca da S; Nascimento, Antonio Rb do; Santos, Antonio C Dos; Omoto, Celso

    2016-12-01

    The frequency of resistance alleles is a major factor influencing the rate of resistance evolution. Here, we adapted the F2 screen procedure for Spodoptera frugiperda (J. E. Smith) with a discriminating concentration assay, and extended associated statistical methods to estimate the frequency of resistance to Cry1F protein in S. frugiperda in Brazil when resistance was not rare. We show that F2 screen is efficient even when the resistance frequency is 0.250. It was possible to screen 517 isoparental lines from 12 populations sampled in five states of Brazil during the first half of 2012. Western Bahia had the highest allele frequency of Cry1F resistance, 0.192, with a 95% confidence interval (CI) between 0.163 and 0.220. All other states had a similar and lower frequency varying from 0.042 in Paraná to 0.080 in Mato Grosso do Sul. The high frequency in western Bahia may be related to year-round availability of maize, the high population density of S. frugiperda, the lack of refuges and the high adoption rate of Cry1F maize. Cry1F resistance alleles were not rare and occurred at frequencies that have already compromised the useful life of TC1507 maize in western Bahia. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  12. An SSH library responsive to azadirachtin A constructed in Spodoptera litura Fabricius cell lines.

    PubMed

    Yan, Chao; Zhang, Zhi-Xiang; Xu, Han-Hong

    2012-05-31

    The present study revealed differentially expressed genes responsive to azadirachtin A (Aza) in Spodoptera litura cell line through suppression subtractive hybridization. In the Aza-responsive SSH library, approximately 270 sequences represent 53 different identified genes encoding proteins with various predicted functions, and the percentages of the gene clusters were 26.09% (genetic information processing), 11.41% (cell growth and death), 7.07% (metabolism), 6.52% (signal transduction/transport) and 2.72% (immunity), respectively. Eleven clones homologous to identified genes were selected to be confirmed through quantitative real time polymerase chain reaction. Among the eleven clones validated, all but one transcript of lipase showed an increase in SL cell line collected from ETA, whereas the transcripts of other genes were lower in the SL cell line collected from ETA compared with that of UETA. These genes were considered to be related to the response of SL cell line to Aza. These will provide a new clue to uncover the molecular mechanisms of Aza acting on SL cell line.

  13. Two genomes of highly polyphagous lepidopteran pests (Spodoptera frugiperda, Noctuidae) with different host-plant ranges.

    PubMed

    Gouin, Anaïs; Bretaudeau, Anthony; Nam, Kiwoong; Gimenez, Sylvie; Aury, Jean-Marc; Duvic, Bernard; Hilliou, Frédérique; Durand, Nicolas; Montagné, Nicolas; Darboux, Isabelle; Kuwar, Suyog; Chertemps, Thomas; Siaussat, David; Bretschneider, Anne; Moné, Yves; Ahn, Seung-Joon; Hänniger, Sabine; Grenet, Anne-Sophie Gosselin; Neunemann, David; Maumus, Florian; Luyten, Isabelle; Labadie, Karine; Xu, Wei; Koutroumpa, Fotini; Escoubas, Jean-Michel; Llopis, Angel; Maïbèche-Coisne, Martine; Salasc, Fanny; Tomar, Archana; Anderson, Alisha R; Khan, Sher Afzal; Dumas, Pascaline; Orsucci, Marion; Guy, Julie; Belser, Caroline; Alberti, Adriana; Noel, Benjamin; Couloux, Arnaud; Mercier, Jonathan; Nidelet, Sabine; Dubois, Emeric; Liu, Nai-Yong; Boulogne, Isabelle; Mirabeau, Olivier; Le Goff, Gaelle; Gordon, Karl; Oakeshott, John; Consoli, Fernando L; Volkoff, Anne-Nathalie; Fescemyer, Howard W; Marden, James H; Luthe, Dawn S; Herrero, Salvador; Heckel, David G; Wincker, Patrick; Kergoat, Gael J; Amselem, Joelle; Quesneville, Hadi; Groot, Astrid T; Jacquin-Joly, Emmanuelle; Nègre, Nicolas; Lemaitre, Claire; Legeai, Fabrice; d'Alençon, Emmanuelle; Fournier, Philippe

    2017-09-25

    Emergence of polyphagous herbivorous insects entails significant adaptation to recognize, detoxify and digest a variety of host-plants. Despite of its biological and practical importance - since insects eat 20% of crops - no exhaustive analysis of gene repertoires required for adaptations in generalist insect herbivores has previously been performed. The noctuid moth Spodoptera frugiperda ranks as one of the world's worst agricultural pests. This insect is polyphagous while the majority of other lepidopteran herbivores are specialist. It consists of two morphologically indistinguishable strains ("C" and "R") that have different host plant ranges. To describe the evolutionary mechanisms that both enable the emergence of polyphagous herbivory and lead to the shift in the host preference, we analyzed whole genome sequences from laboratory and natural populations of both strains. We observed huge expansions of genes associated with chemosensation and detoxification compared with specialist Lepidoptera. These expansions are largely due to tandem duplication, a possible adaptation mechanism enabling polyphagy. Individuals from natural C and R populations show significant genomic differentiation. We found signatures of positive selection in genes involved in chemoreception, detoxification and digestion, and copy number variation in the two latter gene families, suggesting an adaptive role for structural variation.

  14. An insensitive acetylcholinesterase confers resistance to methomyl in the beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae).

    PubMed

    Byrne, F J; Toscano, N C

    2001-04-01

    Two forms of acetylcholinesterase were identified in field populations of the beet armyworm, Spodoptera exigua (Hübner), collected from cotton in San Joaquin Valley, CA. Strains (BESS and BKRR) homogeneous for each variant were isolated and their relative susceptibilities to methomyl, chlorpyrifos, and chlorpyrifos-oxon assessed by topical application bioassay. In comparisons with a laboratory susceptible strain (DOW), BKRR and BESS expressed 68-fold and sevenfold resistance, respectively, to the carbamate methomyl. Neither strain was cross-resistant to chlorpyrifos or its oxygen analog (chlorpyrifos-oxon). In biochemical studies, the BKRR AChE enzyme was approximately 30-fold and sixfold more insensitive to methomyl and chlorpyrifos-oxon, respectively, compared with the DOW enzyme. The correlation between the toxicological and biochemical studies provides strong evidence that target-site insensitivity is an important mechanism of resistance to methomyl. The lack of significant cross-resistance to chlorpyrifos suggests that the insensitive AChE in these field populations was selected by methomyl alone and not by the organophosphate.

  15. Host association of Spodoptera frugiperda (Lepidoptera: Noctuidae) corn and rice strains in Argentina, Brazil, and Paraguay.

    PubMed

    Juárez, M Laura; Murúa, M Gabriela; García, M Gabriela; Ontivero, Marta; Vera, M Teresa; Vilardi, Juan C; Groot, Astrid T; Castagnaro, Atilio P; Gastaminza, Gerardo; Willink, Eduardo

    2012-04-01

    Spodoptera frugiperda (J.E. Smith) is composed of two genetically distinct strains, the so-called corn strain and the rice strain. Whether the two strains differ in their host use is unclear, because laboratory experiments have not been able to show consistent host performance or preference differences between them, and field studies showed high rates of hybridization, as well as some degree asymmetric host use. To determine the distribution of the two strains and their association with host plants, we collected fall armyworm larvae from different crops (corn, rice, alfalfa, and sorghum) and grasses in 15 different localities over 4 yr in Argentina, Brazil, and Paraguay. The strain identity was analyzed using two polymorphisms in the mitochondrial cytochrome oxidase subunit I gene. We identified the corn and rice haplotypes and three types of populations were characterized based on the frequencies of the individuals that belonged to any of these haplotypes: in 44% of populations the corn haplotype predominated, in 44% of populations the rice haplotype was the most frequent, and 11% of populations showed both haplotypes at similar proportions. In total, eight populations (47%) showed the expected pattern, two populations (12%) were polymorphic within the same field, and seven populations (41%) showed the inverse pattern. Taken together, there was no consistent pattern of host association between the two sympatric genotypes and their respective host plants. This investigation supports the need for additional studies to determine which other forces keep the genotypes separate, and what is the degree of genetic differentiation between these populations.

  16. Effects of zinc exposure on the reproduction of Spodoptera litura Fabricius (Lepidoptera: Noctuidae).

    PubMed

    Shu, Yinghua; Gao, Yuanyuan; Sun, Hongxia; Zou, Zhiwen; Zhou, Qiang; Zhang, Guren

    2009-11-01

    Reproductive toxicity of Zn to insects was investigated in this study. By exposing phytophagous insect Spodoptera litura Fabricius to Zn in artificial diets of larvae, we investigated the effects of Zn on reproduction at ecological and molecular levels. A significantly shorter period of laying eggs was observed in S. litura exposed to 300-750mg Zn/kg. The oviposition rate, fecundity and hatchability of female adults treated with 750mg Zn/kg were significantly lower than those of the controls (31.43%, 20.95% and 52%, respectively, compared to the control). The Zn accumulation and vitellin (Vn) content in eggs were tested by inductively coupled plasma-atomic emission spectrometry and Bradford combining Western-blot, respectively. The results showed that Zn accumulated in the eggs, which has affected the weight and Vn content of eggs with significant negative correlations. The down-regulated expression levels of vitellogenin (Vg) mRNA were detected by real-time polymerase chain reaction (RT-PCR): the relative quantity of Vg mRNA was less than half of the controls at higher than 450mg Zn/kg wet weight. These results indicated that excess Zn made expression of Vg gene down-regulated and caused poor accumulation of egg yolk, which led to a reduction in egg numbers and failure of eggs to hatch.

  17. Herbivore- and Elicitor- Induced Resistance in Groundnut to Asian armyworm, Spodoptera litura (Fab.) (Lepidoptera: Noctuidae)

    PubMed Central

    War, Abdul Rashid; Paulraj, Michael Gabriel; War, Mohd Yousf; Ignacimuthu, Savarimuthu

    2011-01-01

    Induced defense was studied in three groundnut genotypes ICGV 86699 (resistant), NCAc 343 (resistant) and TMV 2 (susceptible) in response to Spodoptera litura infestation and jasmonic acid (JA) application. The activity of the oxidative enzymes [peroxidase (POD) and polyphenol oxidase (PPO)] and the amounts other host plant defense components [total phenols, hydrogen peroxide (H2O2), malondialdehyde (MDA), and protein content] were recorded at 24, 48, 72 and 96 h in JA pretreated (one day before) plants and infested with S. litura, and JA application and simultaneous infestation with S. litura to understand the defense response of groundnut genotypes against S. litura damage. Data on plant damage, larval survival and larval weights were also recorded. There was a rapid increase in the activities of POD and PPO and in the quantities of total phenols, H2O2, MDA and protein content in the JA pretreated + S. litura infested plants. All the three genotypes showed quick response to JA application and S. litura infestation by increasing the defensive compounds. Among all the genotypes, higher induction was recorded in ICGV 86699 in most of the parameters. Reduced plant damage, low larval survival and larval weights were observed in JA pretreated plants. It suggests that pretreatment with elicitors, such as JA could provide more opportunity for plant defense against herbivores. PMID:22042128

  18. Proteomic analysis of Cry2Aa-binding proteins and their receptor function in Spodoptera exigua

    PubMed Central

    Qiu, Lin; Zhang, Boyao; Liu, Lang; Ma, Weihua; Wang, Xiaoping; Lei, Chaoliang; Chen, Lizhen

    2017-01-01

    The bacterium Bacillus thuringiensis produces Crystal (Cry) proteins that are toxic to a diverse range of insects. Transgenic crops that produce Bt Cry proteins are grown worldwide because of their improved resistance to insect pests. Although Bt “pyramid” cotton that produces both Cry1A and Cry2A is predicted to be more resistant to several lepidopteran pests, including Spodoptera exigua, than plants that produce Cry1Ac alone, the mechanisms responsible for the toxicity of Cry2Aa in S. exigua are not well understood. We identified several proteins that bind Cry2Aa (polycalin, V-ATPase subunits A and B, actin, 4-hydroxybutyrate CoA-transferase [4-HB-CoAT]), and a receptor for activated protein kinase C (Rack), in S. exigua. Recombinant, expressed versions of these proteins were able to bind the Cry2Aa toxin in vitro assays. RNA interference gene knockdown of the Se-V-ATPase subunit B significantly decreased the susceptibility of S. exigua larvae to Cry2Aa, whereas knockdown of the other putative binding proteins did not. Moreover, an in vitro homologous competition assay demonstrated that the Se-V-ATPase subunit B binds specifically to the Cry2Aa toxin, suggesting that this protein acts as a functional receptor of Cry2Aa in S. exigua. This the first Cry2Aa toxin receptor identified in S. exigua brush-border membrane vesicles. PMID:28067269

  19. Toxicity and kinetics of methoxyfenozide in greenhouse-selected Spodoptera exigua (Lepidoptera: Noctuidae).

    PubMed

    Smagghe, Guy; Pineda, Samuel; Carton, Bert; Del Estal, Pedro; Budia, Flor; Viñuela, Elisa

    2003-11-01

    Methoxyfenozide (RH-2485) was found to be 7.5-fold less toxic in terms of LD50 values against last-instar larvae of a greenhouse-selected strain of the beet armyworm Spodoptera exigua (Hübner) that was collected in July 2001 in an experimental greenhouse for resistance at Murcia in southern Spain, in comparison with a laboratory susceptible strain. To date, the compound is the newest member of this new group of moulting hormone accelerating IGRs to reach the marketplace against Lepidoptera. To understand this different potency in the greenhouse-selected S exigua, oxidative metabolism and acetylcholinesterase activities were measured in last-instar larvae and adults. In addition, we determined, by the use of 14C-labelled methoxyfenozide, the pattern of absorption in body tissues and excretion via faeces in last-instar larvae of the greenhouse-selected strain and compared the results with those from the laboratory susceptible strain. It was striking that the rate of excretion was about twice as high in the greenhouse-selected strain, resulting in a more rapid clearance of insecticide amounts from the insect body. Data are discussed in relation to mechanisms of lower toxicities for this new group of IGRs.

  20. REPAT, a new family of proteins induced by bacterial toxins and baculovirus infection in Spodoptera exigua.

    PubMed

    Herrero, Salvador; Ansems, Marleen; Van Oers, Monique M; Vlak, Just M; Bakker, Petra L; de Maagd, Ruud A

    2007-11-01

    Insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. In our study, suppression subtractive hybridization (SSH) was used to compare Spodoptera exigua midgut gene expression between larvae exposed to the Bacillus thuringiensis Cry1Ca toxin and non-exposed insects. Based on the SSH results, full cDNA sequences coding for four homologous proteins were obtained. Quantitative and semi-quantitative RT-PCR showed the increased expression of the genes coding for these proteins after exposure to different B. thuringiensis toxins as well as after infection with baculovirus. The proteins were named REPAT after their increased expression in Response to Pathogen. REPAT1, a member of this family, was recombinantly expressed using the baculovirus expression system, revealing the glycosylated nature of the protein. Recombinant baculoviruses expressing REPAT1 were used to infect larvae from S. exigua, showing that expression of REPAT1 was reducing the virulence of baculovirus to the infected larvae. Together, these results suggest a role for REPAT1 in mitigating pathological effects.

  1. Identification and Expression Profiles of Sex Pheromone Biosynthesis and Transport Related Genes in Spodoptera litura.

    PubMed

    Zhang, Ya-Nan; Zhu, Xiu-Yun; Fang, Li-Ping; He, Peng; Wang, Zhi-Qiang; Chen, Geng; Sun, Liang; Ye, Zhan-Feng; Deng, Dao-Gui; Li, Jin-Bu

    2015-01-01

    Although the general pathway of sex pheromone synthesis in moth species has been established, the molecular mechanisms remain poorly understood. The common cutworm Spodoptera litura is an important agricultural pest worldwide and causes huge economic losses annually. The female sex pheromone of S. litura comprises Z9,E11-14:OAc, Z9,E12-14:OAc, Z9-14:OAc, and E11-14:OAc. By sequencing and analyzing the transcriptomic data of the sex pheromone glands, we identified 94 candidate genes related to pheromone biosynthesis (55 genes) or chemoreception (39 genes). Gene expression patterns and phylogenetic analysis revealed that two desaturase genes (SlitDes5 and SlitDes11) and one fatty acyl reductase gene (SlitFAR3) showed pheromone gland (PG) biased or specific expression, and clustered with genes known to be involved in pheromone synthesis in other moth species. Furthermore, 4 chemoreception related genes (SlitOBP6, SlitOBP11, SlitCSP3, and SlitCSP14) also showed higher expression in the PG, and could be additional candidate genes involved in sex pheromone transport. This study provides the first solid background information that should facilitate further elucidation of sex pheromone biosynthesis and transport, and indicates potential targets to disrupt sexual communication in S. litura for a novel pest management strategy.

  2. Managing fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), with Bt maize and insecticides in southern Brazil.

    PubMed

    Burtet, Leonardo M; Bernardi, Oderlei; Melo, Adriano A; Pes, Maiquel P; Strahl, Thiago T; Guedes, Jerson Vc

    2017-07-11

    Maize plants expressing insecticidal proteins of Bacillus thuringiensis are valuable options for managing fall armyworm (FAW), Spodoptera frugiperda, in Brazil. However, control failures were reported, and therefore insecticides have been used to control this species. Based on these, we evaluated the use of Bt maize and its integration with insecticides against FAW in southern Brazil. Early-planted Agrisure TL, Herculex, Optimum Intrasect and non-Bt maize plants were severely damaged by FAW and required up to three insecticidal sprays. In contrast, YieldGard VT Pro, YieldGard VT Pro 3, PowerCore, Agrisure Viptera and Agrisure Viptera 3 showed little damage and did not require insecticides. Late-planted Bt maize plants showed significant damage by FAW and required up to four sprays, with the exceptions of Agrisure Viptera and Agrisure Viptera 3. Exalt (first and second sprays); Lannate + Premio (first spray) and Avatar (second spray); and Karate + Match (first spray) and Ampligo (second spray) were the most effective insecticides against FAW larvae in Bt and non-Bt maize. Maize plants expressing Cry proteins exhibited FAW control failures in southern Brazil, necessitating insecticidal sprays. In contrast, Bt maize containing the Vip3Aa20 protein remained effective against FAW. However, regardless of the insecticide used against FAW surviving on Bt maize, grain yields were similar. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. Distribution of elongation factor-1α in larval tissues of the fall armyworm, Spodoptera frugiperda

    PubMed Central

    Habibi, Javad; Goodman, Cynthia L.; Stuart, Melissa K.

    2006-01-01

    Elongation factor-1α (EF-1α) promotes the delivery of aminoacyl-tRNA to the acceptor site of the ribosome during protein synthesis. The enzyme has a number of additional functions, including regulation of apoptosis and interaction with the cytoskeleton. We determined the distribution of EF-1α in larval tissues of the fall armyworm, Spodoptera frugiperda, with a monoclonal antibody generated to EF-1α from Sf21 cells, a cell line developed from ovarian tissue of S. frugiperda. Enzyme-linked immunosorbent assay showed that EF-1α comprised 1.9–9.9 % of the total protein within the tissues that were examined, which included fat body, Malpighian tubules, midgut, muscle, salivary glands, trachea, and ventral nerve cord. To a certain extent, EF-1α concentrations reflected the expected metabolic activity level of each of the represented tissues. Closer examination by immunofluorescence microscopy revealed that EF-1α concentrations varied among different cell types within a given tissue, i.e. midgut columnar epithelial cells yielded strong signals, while goblet cells failed to react with the EF-1α -specific antibody. PMID:19537984

  4. Analysis and functional annotation of expressed sequence tags from the fall armyworm Spodoptera frugiperda

    PubMed Central

    Deng, Youping; Dong, Yinghua; Thodima, Venkata; Clem, Rollie J; Passarelli, A Lorena

    2006-01-01

    Background Little is known about the genome sequences of lepidopteran insects, although this group of insects has been studied extensively in the fields of endocrinology, development, immunity, and pathogen-host interactions. In addition, cell lines derived from Spodoptera frugiperda and other lepidopteran insects are routinely used for baculovirus foreign gene expression. This study reports the results of an expressed sequence tag (EST) sequencing project in cells from the lepidopteran insect S. frugiperda, the fall armyworm. Results We have constructed an EST database using two cDNA libraries from the S. frugiperda-derived cell line, SF-21. The database consists of 2,367 ESTs which were assembled into 244 contigs and 951 singlets for a total of 1,195 unique sequences. Conclusion S. frugiperda is an agriculturally important pest insect and genomic information will be instrumental for establishing initial transcriptional profiling and gene function studies, and for obtaining information about genes manipulated during infections by insect pathogens such as baculoviruses. PMID:17052344

  5. Inhibition of the responses to sex pheromone of the fall armyworm, Spodoptera frugiperda.

    PubMed

    Malo, Edi A; Rojas, Julio C; Gago, Rafael; Guerrero, Ángel

    2013-01-01

    Trifluoromethyl ketones reversibly inhibit pheromone-degrading esterases in insect olfactory tissues, affecting pheromone detection and behavior of moth males. In this work, (Z)-9-tetradecenyl trifluoromethyl ketone (Z9-14:TFMK), a closely-related analogue of the pheromone of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), was prepared and tested in electroantennogram and field tests as possible inhibitors of the pheromone action. The electroantennogram parameters, amplitude, and the repolarization time of the antennal responses of S. frugiperda males were affected by Z9-14:TFMK vapors. Exposure of male antennae to a stream of air passing through 100 μg of the ketone produced a significant reduction of the amplitude and an increase of 2/3 repolarization time signals to the pheromone. The effect was reversible and dose-dependent. In the field, the analogue significantly decreased the number of males caught when mixed with the pheromone in 10:1 ratio. The results suggest that Z9-14:TFMK is a mating disruptant of S. frugiperda and may be a good candidate to consider in future strategies to control this pest.

  6. Population variation of the fall armyworm, Spodoptera frugiperda, in the Western Hemisphere.

    PubMed

    Clark, Pete L; Molina-Ochoa, Jaime; Martinelli, Samuel; Skoda, Steven R; Isenhour, David J; Lee, Donald J; Krumm, Jeffrey T; Foster, John E

    2007-01-01

    Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), the fall armyworm is the most economically important maize pest in the western hemisphere. This research focused on the genetic variability of the maize host strain because there is a lack of information in this area of S. frugiperda research. Amplified fragment length polymorphism (AFLP) was used to assess the genetic variability of S. frugiperda over a large geographic area. Twenty populations were collected from the maize, one population was collected from princess tree, one population was collected from lemon tree, and one population was collected from bermudagrass. The 23 populations were from Mexico, the continental United States, Puerto Rico, Brazil, and Argentina. The objective of this research was to evaluate whether the majority of genetic variability was within populations or between populations. The AFLP results showed that the majority of the genetic variability is within populations and not between populations, indicating minor gene flow and suggesting that S. frugiperda in the Western Hemisphere are an interbreeding population.

  7. Inhibition of the Responses to Sex Pheromone of the Fall Armyworm, Spodoptera frugiperda

    PubMed Central

    Malo, Edi A.; Rojas, Julio C.; Gago, Rafael; Guerrero, Ángel

    2013-01-01

    Trifluoromethyl ketones reversibly inhibit pheromone-degrading esterases in insect olfactory tissues, affecting pheromone detection and behavior of moth males. In this work, (Z)-9-tetradecenyl trifluoromethyl ketone (Z9-14:TFMK), a closely-related analogue of the pheromone of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), was prepared and tested in electroantennogram and field tests as possible inhibitors of the pheromone action. The electroantennogram parameters, amplitude, and the repolarization time of the antennal responses of S. frugiperda males were affected by Z9-14:TFMK vapors. Exposure of male antennae to a stream of air passing through 100 ìg of the ketone produced a significant reduction of the amplitude and an increase of 2/3 repolarization time signals to the pheromone. The effect was reversible and dose-dependent. In the field, the analogue significantly decreased the number of males caught when mixed with the pheromone in 10:1 ratio. The results suggest that Z9-14:TFMK is a mating disruptant of S. frugiperda and may be a good candidate to consider in future strategies to control this pest. PMID:24766416

  8. Distribution of elongation factor-1alpha in larval tissues of the fall armyworm, Spodoptera frugiperda.

    PubMed

    Habibi, Javad; Goodman, Cynthia L; Stuart, Melissa K

    2006-01-01

    Elongation factor-1alpha (EF-1alpha) promotes the delivery of aminoacyl-tRNA to the acceptor site of the ribosome during protein synthesis. The enzyme has a number of additional functions, including regulation of apoptosis and interaction with the cytoskeleton. We determined the distribution of EF-1alpha in larval tissues of the fall armyworm, Spodoptera frugiperda , with a monoclonal antibody generated to EF-1alpha from Sf21 cells, a cell line developed from ovarian tissue of S. frugiperda. Enzyme-linked immunosorbent assay showed that EF-1alpha comprised 1.9-9.9% of the total protein within the tissues that were examined, which included fat body, Malpighian tubules, midgut, muscle, salivary glands, trachea, and ventral nerve cord. To a certain extent, EF-1alpha concentrations reflected the expected metabolic activity level of each of the represented tissues. Closer examination by immunofluorescence microscopy revealed that EF-1alpha concentrations varied among different cell types within a given tissue, i.e. midgut columnar epithelial cells yielded strong signals, while goblet cells failed to react with the EF-1alpha-specific antibody.

  9. Cytochrome P450s from the fall armyworm (Spodoptera frugiperda): responses to plant allelochemicals and pesticides.

    PubMed

    Giraudo, M; Hilliou, F; Fricaux, T; Audant, P; Feyereisen, R; Le Goff, G

    2015-02-01

    Spodoptera frugiperda is a polyphagous lepidopteran pest that encounters a wide range of toxic plant metabolites in its diet. The ability of this insect to adapt to its chemical environment might be explained by the action of major detoxification enzymes such as cytochrome P450s (or CYP). Forty-two sequences coding for P450s were identified and most of the transcripts were found to be expressed in the midgut, Malpighian tubules and fat body of S. frugiperda larvae. Relatively few P450s were expressed in the established cell line Sf9. In order to gain information on how these genes respond to different chemical compounds, larvae and Sf9 cells were exposed to plant secondary metabolites (indole, indole-3-carbinol, quercetin, 2-tridecanone and xanthotoxin), insecticides (deltamethrin, fipronil, methoprene, methoxyfenozide) or model inducers (clofibrate and phenobarbital). Several genes were induced by plant chemicals such as P450s from the 6B, 321A and 9A subfamilies. Only a few genes responded to insecticides, belonging principally to the CYP9A family. There was little overlap between the response in vivo measured in the midgut and the response in vitro in Sf9 cells. In addition, regulatory elements were detected in the promoter region of these genes. In conclusion, several P450s were identified that could potentially be involved in the adaptation of S. frugiperda to its chemical environment. © 2014 The Royal Entomological Society.

  10. Characterization of a novel peptide with allatotropic activity in the fall armyworm Spodoptera frugiperda.

    PubMed

    Abdel-latief, Mohatmed; Meyering-Vos, Martina; Hoffmann, Klaus H

    2004-10-15

    A cDNA that encodes 53 amino acids, including one copy of the RVRGNPISCF-OH peptide, was cloned from Spodoptera frugiperda. This peptide strongly stimulates the synthesis and release of juvenile hormone (JH) in vitro by the corpora allata (CA) of S. frugiperda and was code-named Spofr-AT 2. Northern blotting and reverse transcriptase polymerase chain reaction (RT-PCR) analyses revealed that the preprohormone is expressed as one transcript in the brain, midgut (Mg) and ovary (Ov) in a tissue- and developmental-specific manner. Whole-mount in situ hybridization confirmed the gene expression in the suboesophageal ganglion (SOG) and in the ovary of adult females. Treating the CA with the synthetic peptide caused an up to tenfold increase in the release of JH. The stimulation was dose-dependent with an apparent EC(50) of ca. 10(-7) M. CA that were activated with Spofr-AT 2 could be inhibited by the addition of synthetic allatostatin type-C from Manduca sexta (Manse-AS). This is the first report on the presence and function of two different peptides with allatotropic activity in an insect species.

  11. Feeding underground: kinematics of feeding in caecilians.

    PubMed

    Herrel, Anthony; Measey, G John

    2012-11-01

    Caecilians are limbless amphibians that have evolved distinct cranial and postcranial specializations associated with a burrowing lifestyle. Observations on feeding behavior are rare and restricted to above-ground feeding in laboratory conditions. Here we report data on feeding in tunnels using both external video and X-ray recordings of caecilians feeding on invertebrate prey. Our data show feeding kinematics similar to those previously reported, including the pronounced neck bending observed during above-ground feeding. Our data illustrate, however, that caecilians may be much faster than previously suspected, with lunge speeds of up to 7 cm sec(-1). Although gape cycles are often slow (0.67 ± 0.29 sec), rapid jaw closure is observed during prey capture, with cycle times and jaw movement velocities similar to those observed in other terrestrial tetrapods. Finally, our data suggest that gape angles may be large (64.8 ± 18°) and that gape profiles are variable, often lacking distinct slow and fast opening and closing phases. These data illustrate the importance of recording naturalistic feeding behavior and shed light on how these animals are capable of capturing and processing prey in constrained underground environments. Additional data on species with divergent cranial morphologies would be needed to better understand the co-evolution between feeding, burrowing, and cranial design in caecilians.

  12. Identification of α-tocopherol and α-tocopheryl acetate from the cuticle of soybean pods armyworm (Spodoptera cosmioides).

    PubMed

    Fronza, Edegar; Migues, Ignacio; Specht, Alexandre; de Barros, Neiva Monteiro; Heinzen, Horacio

    2013-01-01

    The chemical composition of the soybean pods armyworm Spodoptera cosmioides (Walker, 1858) (Lepidoptera: Noctuidae) and Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Erebidae) larval cuticles was evaluated using gas chromatography coupled to a mass detector (GC-MS). Among the usual lipids found in the insect cuticle, α-tocopherol and α-tocopheryl acetate were also isolated from S. cosmioides. On the other hand, no vitamin E derivative was found in A. gemmatalis exuvia. This is the first report of vitamin E occurrence in the insect's cuticle.

  13. Sustainable synthesis of flavonoid derivatives, QSAR study and insecticidal activity against the fall armyworm, Spodoptera frugiperda (Lep.: Noctuidae).

    PubMed

    Romanelli, Gustavo P; Virla, Eduardo G; Duchowicz, Pablo R; Gaddi, Ana L; Ruiz, Diego M; Bennardi, Daniel O; Del Valle Ortiz, Erlinda; Autino, Juan C

    2010-05-26

    A simple, clean, solvent-free preparation of flavones by the use of a silica-supported Preyssler heteropolyacid as reusable catalyst is described. High selectivity and very good yields (87-94%) were obtained in short reaction times (7-13 min). Bioassays for insecticidal activity against Spodoptera frugiperda were carried out with a set of flavones. Bioassays showed that some of the flavones had moderate insecticidal activity. Quantitative structure-activity relationships were established on the available data with the purpose of predicting the insecticidal activity of a number of structurally related flavones. A relationship between the molecular structure and biological activity is proposed.

  14. Nasogastric feeding tube

    MedlinePlus

    Feeding - nasogastric tube; NG tube; Bolus feeding; Continuous pump feeding; Gavage tube ... If your child has an NG tube, try to keep your child from touching or pulling on the tube. After your nurse teaches you how to flush the tube ...

  15. Feeding Young Children.

    ERIC Educational Resources Information Center

    Poulton, Suzanne; Sexton, David

    1996-01-01

    Presents a digest of basic developmental information about children's feeding skills and behaviors, and gives general feeding recommendations. Also addresses requirements for feeding children with developmental disabilities and chronic medical conditions for which adapted environments or monitored nutrient intake may be necessary. (ET)

  16. Sex pheromone of the Spanish population of the beet armyworm Spodoptera exigua.

    PubMed

    Acín, Patricia; Rosell, Gloria; Guerrero, Angel; Quero, Carmen

    2010-07-01

    The pheromone composition of the Spanish population of the beet armyworm (BAW), Spodoptera exigua (Lepidoptera: Noctuidae), was identified. Analysis of female gland extracts showed the presence of compounds Z9,E12-14:Ac (1), Z9-14:Ac (2), Z11-16:Ac (3), Z9,E12-14:OH (4), Z9-14:OH (5), and Z11-16:OH (6) in a ratio of 26:11:1:22:31:9. The amount of compound per gland ranged from 2.08 ng for 5 to 0.09 ng for 3. However, analysis of female volatiles by SPME revealed only the presence of compounds, 1, 2, 3, and 5 in a 34:40:4:22 ratio. In electroantennogram assays, compound 1 elicited the highest response, and the C14 acetates evoked higher electrophysiological responses than the corresponding alcohols or C16 isomers. In a wind tunnel, no behavioral difference was observed between formulations based on the gland extracts and female volatiles. In both cases, males responded as when virgin females were used as the attractant source. Compound 1 alone elicited upwind flight by males, but required the presence of compound 5 in a 80:20 to 40:60 ratio for full activity. Ternary mixtures of 1, 5 and the minor components did not improve the performance of the 1+5 blend in a 60:40 ratio. In the field, the mixture 1+5+3 in a 56:37:7 ratio was the most attractive formulation, and is expected to be useful in future pest control strategies.

  17. Insecticide resistance status of field populations of Spodoptera exigua (Lepidoptera: Noctuidae) from China.

    PubMed

    Che, Wunan; Shi, Tian; Wu, Yidong; Yang, Yihua

    2013-08-01

    Beet armyworm, Spodoptera exigua (Hübner), is a serious pest of vegetables in China, and its control is heavily dependent on chemical insecticides. The current resistance status of nine insecticides was investigated in 16 field populations collected from seven provinces of China during 2009-2012. Compared with the susceptible strain WH-S, some field populations evolved various levels of resistance to eight of the nine insecticides tested: emamectin benzoate (4- to 348-fold), indoxacarb (2- to 41-fold), spinosad (5- to 38-fold), chlorantraniliprole (2- to 44-fold), tebufenozide (2- to 87-fold), chlorfluazuron (3- to 31-fold), cypermethrin (79- to 1240-fold), and chlorpyrifos (8- to 3,080-fold), but no significant resistance was detected to chlorfenapyr (0.4- to 7-fold). This indicates that chlorfenapyr has no cross-resistance with these other currently used insecticides. Four consecutive years' resistance screening at two places shows that resistance patterns were different between populations from Luhe (Jiangsu Province) and Fengxian (Shanghai), which are approximately 300 km apart. Resistance levels to chlorpyrifos were much higher in populations from Luhe (877- to 3,080-fold) than from Fengxian (8- to 110-fold). Fengxian populations developed moderate levels of resistance to tebufenozide (13- to 87-fold), but no resistance in Luhe populations (2- to 6-fold). However, Luhe populations developed moderate levels of resistance to chlorfluazuron (21- to 31-fold), but there was no resistance in Fengxian populations (3- to 5-fold). It is suggested that local insecticide selection determined resistance patterns although S. exigua has long-distance migratory potential. Adaptive resistance management tactics (such as rotations) should be designed and implemented based on the resistance patterns of S. exigua for each geographic area.

  18. Response of the Cutworm Spodoptera litura to Sesame Leaves or Crude Extracts in Diet

    PubMed Central

    Ofosuhene Sintim, Henry; Tashiro, Toru; Motoyama, Naoki

    2009-01-01

    The effects of extracts of sesame, Sesamum indicum L. (Liamiales: Pedaliaceae), and whole leaves of some selected cultivars of sesame were tested using a natural host Spodoptera litura (F.) (Lepidoptera: Noctuidae). Indices taken using the immature stages include; diet utilization, growth and development and induction of detoxification enzymes. The results indicate that S. litura generally selects its food amongst cultivars within 6 hours after food presentation. Growth and development of the insect is controlled also by plant acceptability and quality. Although all the cultivars tested significantly limit insect growth and development the variety 56S-radiatum did not allow a complete life cycle as pupation from first instar stage was 0%. Generally the crucial period for immature S. litura was the larval period, especially the first two instars where the weight of an insect fed on an experimental diet was three times lower than that of a control diet. The larval developmental period was greater than 40 days as compared to 17 days for insects fed a control diet. S. litura also had lowered efficiency in utilizing ingested food, from a low of 13% in a sesame cultivar to 45% in the control diet. The key detoxification enzyme was a glutathione s-transferase that was confirmed by a 6-fold increase between S. litura fed a plant cultivar vs. a control diet towards the substrate 1,2-dichloro-4-nitrobenzene. First and second instars of S. litura have a relatively reduced detoxification of enzymes in response to plant cultivar diets leading to low survival. A 3% v/w crude extract of the cultivars increased enzyme induction towards all the tested substrates. PMID:20050772

  19. Cross-resistance and Inheritance of Resistance to Emamectin Benzoate in Spodoptera exigua (Lepidoptera: Noctuidae).

    PubMed

    Che, Wunan; Huang, Jianlei; Guan, Fang; Wu, Yidong; Yang, Yihua

    2015-08-01

    Beet armyworm, Spodoptera exigua (Hübner), is a worldwide pest of many crops. Chemical insecticides are heavily used for its control in China, and serious resistance has been evolved in the field to a variety of insecticides including emamectin benzoate. Through repeated backcrossing to a susceptible strain (WH-S) and selection with emamectin benzoate, the trait conferring resistance to emamectin benzoate in a field-collected population of S. exigua (moderately resistant to emamectin benzoate and strongly resistant to pyrethroids and indoxacarb) was introgressed into WH-S to generate a near-isogenic resistant strain (WH-EB). Compared with WH-S, the WH-EB strain developed a 1,110-fold resistance to emamectin benzoate and a high level of cross-resistance to abamectin (202-fold), with low levels of cross-resistance to cypermethrin (10-fold) and chlorfluazuron (7-fold), but no cross-resistance to representatives of another six different classes of insecticides (chlorantraniliprole, chlorfenapyr, indoxacarb, spinosad, tebufenozide, and chlorpyrifos). Resistance to emamectin benzoate in WH-EB was autosomal, incompletely dominant, and polygenic. Limited cross-resistance in WH-EB indicates that emamectin benzoate can be rotated with other classes of insecticides to which it does not show cross-resistance to delay the evolution of resistance in S. exigua. The incompletely dominant nature of resistance in S. exigua may explain the rapid evolution of resistance to emamectin benzoate in the field, and careful deployment of this chemical within a resistance management program should be considered. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Seasonal Pattern of Spodoptera litura (Lepidoptera: Noctuidae) Migration Across the Bohai Strait in Northern China.

    PubMed

    Fu, Xiaowei; Zhao, Xiaoyang; Xie, Bingtang; Ali, Abid; Wu, Kongming

    2015-04-01

    The common cutworm, Spodoptera litura (F.), is a serious crop pest with a strong migratory ability. Previous studies on the migration of S. litura were mostly carried out in its "year-round breeding region" (YBR) or "overwintering region" (OR). However, the pattern of seasonal movements in its "summer breeding region" (SBR; i.e., northern China where they cannot overwinter) remains unknown. Here, we present data from an 11-yr study of this species made by searchlight trapping on Beihuang (BH) Island in the center of the Bohai Strait, which provides direct evidence that S. litura regularly migrates across this sea. There was considerable yearly and monthly variation in the number of S. litura trapped on BH, with the vast majority trapped in the autumn. The mean time from the earliest trapping to the latest trapping within a year was 110±12 d during 2003-2013, with the shortest time span of 40 d in 2003 and the longest of 166 d in 2012. S. litura moths had downwind displacement rather than randomly by heading toward their seasonally favorable direction (i.e. toward southwest in the four autumn migration events by prevailing northeasterly winds). Some females trapped in July showed a relatively higher proportion of having mated and a degree of ovarian development, suggesting that the migration of this species is not completely bound by the "oogenesis-flight syndrome." These findings provide a good starting point of research on S. litura migration between its OR (or YBR) and SBR, which will help us develop more effective regional management strategies against this pest.

  1. In vivo recombination between two strains of the genus Nucleopolyhedrovirus in its natural host, Spodoptera exigua.

    PubMed Central

    Muñoz, D; Vlak, J M; Caballero, P

    1997-01-01

    The DNA restriction map for the enzymes BamHI, BglII, PstI, and XbaI of SeMNPV-US (Se-US), the best-studied Nucleopolyhedrovirus strain isolated from Spodoptera exigua in California, was used as a reference to construct that of SeMNPV-SP2 (Se-SP2), a closely related Spanish strain of the same virus. After coinfection of S. exigua with both the Se-US and Se-SP2 strains per os, a recombinant virus (SeMNPV-SUR1 [Se-SUR1]) was detected after one passage which quickly replaced the parental viruses. A physical map of Se-SUR1 DNA was constructed for BamHI, BglII, PstI, and XbaI and compared to that of the parental viruses, Se-US and Se-SP2. Se-SUR1 is the result of at least four crossover events between Se-US and Se-SP2 and not of selection of a minor variant in one of the parental viruses. Bioassays of the recombinant and parental strains against L2 beet armyworm larvae demonstrated that their 50% lethal dose values were not significantly different. The differences in median lethal time values are too small to explain the replacement of the parental viruses by the recombinant virus upon successive passage in vivo, although it cannot be ruled out as an explanation for the selective advantage of the recombinant strain, Se-SUR1. The consequences of the release of nonindigenous or recombinant baculovirus strains in agro-ecosystems are discussed. PMID:9251191

  2. Effects of Pyriproxyfen on Female Reproduction in the Common Cutworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae)

    PubMed Central

    Xu, Qi; Tang, Bin; Zou, Qi; Zheng, Huizhen; Liu, Xiaojun; Wang, Shigui

    2015-01-01

    The common cutworm, Spodoptera litura, is a rapidly reproducing pest of numerous agricultural ecosystems worldwide. The use of pesticides remains the primary means for controlling S. litura, despite their negative ecological impact and potential threat to human health. The use of exogenous hormone analogs may represent an alternative to insecticides. Juvenile hormones (JHs) play an important role in the reproductive systems of female insects, but the effects of pyriproxyfen, a JH analog, on reproduction in S. litura were poorly understood. In this paper, we topically treated the newly emerged females with 20, 60, or 100 μg of pyriproxyfen to determine its effects on reproduction. Then, we examined the expression of vitellogenin (Vg) and three hormone receptors, USP, HR3, and EcR, using quantitative reverse transcription and real-time polymerase chain reaction (qRT-PCR), and found that pyriproxyfen up-regulated the expression of Vg, USP, and HR3, whereas the expression of EcR was unaffected. An analysis of fecundity showed that the peak oviposition day, lifespan, and oviposition period were progressively shortened as the pyriproxyfen dosage increased. We also found that pyriproxyfen decreased egg laying amount, whereas the number of mature eggs that remained in the ovarioles of dead females increased as the pyriproxyfen dosage increased. We examined oocytes using transmission electron microscopy and found that treatment with 100 μg of pyriproxyfen increased the metabolism by increasing the amount of rough endoplasmic reticulum and mitochondria in the primary oocytes. Our results suggest that the topical application of pyriproxyfen on newly emerged females can efficiently reduce reproduction in S. litura and may represent an alternative to the use of insecticides for controlling the agricultural pest. PMID:26444432

  3. Testing the joint effects hypothesis of elemental defense using Spodoptera exigua.

    PubMed

    Cheruiyot, Dorothy J; Boyd, Robert S; Moar, William

    2015-02-01

    Metal hyperaccumulation may be an elemental defense, in which high concentrations of a metal in plant tissues decrease herbivore survival or growth rate. The Joint Effects Hypothesis suggests that a combination of metals, or a combination of a metal with an organic compound, may have an enhanced defensive effect. The enhancement may be additive or synergistic: in either case the concentration of a particular metal necessary to provide a defensive benefit for the plant is lowered. We tested the Joint Effects Hypothesis using Spodoptera exigua (beet armyworm) neonates fed artificial diets. Metal + metal experiments utilized diets amended with metal pairs, using four metals commonly hyperaccumulated by plants (Co, Cu, Ni, and Zn). We also conducted metal + organic compound experiments, pairing each metal with nicotine, mustard seed powder, or tannic acid. We tested for joint effects using both lethal (LC20 levels) and sublethal concentrations (10-25 % reduced larval weight) of the chemicals tested. For all experiments, either additive or synergistic effects were found. Of the metal + metal pairs tested, three (Co + Cu, Cu + Zn, and Ni + Zn) were synergistic in lethal concentration tests and only Co + Cu was synergistic in sublethal tests. For metal + organic combination lethal tests, synergism occurred for all combinations except for Co or Ni + nicotine, Ni + mustard seed powder, and Zn + nicotine. For sublethal tests, Zn + all three organic chemicals, Co + mustard seed powder or tannic acid, and Cu + nicotine, were synergistic. These results support the Joint Effects Hypothesis, suggesting that metals combined with other metals or organic compounds may be more effective against herbivores than individual metals.

  4. Constitutive Activation of the Midgut Response to Bacillus thuringiensis in Bt-Resistant Spodoptera exigua

    PubMed Central

    Hernández-Martínez, Patricia; Navarro-Cerrillo, Gloria; Caccia, Silvia; de Maagd, Ruud A.; Moar, William J.; Ferré, Juan; Escriche, Baltasar; Herrero, Salvador

    2010-01-01

    Bacillus thuringiensis is the most effective microbial control agent for controlling numerous species from different insect orders. The main threat for the long term use of B. thuringiensis in pest control is the ability of insects to develop resistance. Thus, the identification of insect genes involved in conferring resistance is of paramount importance. A colony of Spodoptera exigua (Lepidoptera: Noctuidae) was selected for 15 years in the laboratory for resistance to Xentari™, a B. thuringiensis-based insecticide, reaching a final resistance level of greater than 1,000-fold. Around 600 midgut ESTs were analyzed by DNA-macroarray in order to find differences in midgut gene expression between susceptible and resistant insects. Among the differentially expressed genes, repat and arylphorin were identified and their increased expression was correlated with B. thuringiensis resistance. We also found overlap among genes that were constitutively over-expressed in resistant insects with genes that were up-regulated in susceptible insects after exposure to Xentari™, suggesting a permanent activation of the response to Xentari™ in resistant insects. Increased aminopeptidase activity in the lumen of resistant insects in the absence of exposure to Xentari™ corroborated the hypothesis of permanent activation of response genes. Increase in midgut proliferation has been proposed as a mechanism of response to pathogens in the adult from several insect species. Analysis of S. exigua larvae revealed that midgut proliferation was neither increased in resistant insects nor induced by exposure of susceptible larvae to Xentari™, suggesting that mechanisms other than midgut proliferation are involved in the response to B. thuringiensis by S. exigua larvae. PMID:20862260

  5. Effects of green manure cover crops on Spodoptera litura (Lepidoptera: Noctuidae) populations.

    PubMed

    Tuan, Shu-Jen; Li, Nian-Jhen; Yeh, Chih-Chun; Tang, Li-Cheng; Chi, Hsin

    2014-06-01

    Spodoptera litura (F.) is an important pest of numerous agro-economic crops, including green manure cover crops. In Taiwan, sesbania (Sesbanin roxburghii Merr.), sunn hemp (Crotalaria juncea L.), and rapeseed (Brassicae campestris L. variety chinensis) are the most popular green manure crops; sesbania and sunn hemp are commonly planted in warm seasons, whereas rapeseed is grown in the winter. In this study, life-table data for S. litura reared on these three green manures were collected to evaluate their roles as refuges of this pest. The net reproductive rate, intrinsic rate of increase, and finite rate of increase of S. litura were the highest when reared on sesbania (1428.1 offspring, 0.2327 d(-1), 1.2621 d(-1)), followed by sunn hemp (778.4 offspring, 0.2070 d(-1), 1.2300 d(-1)) and rapeseed (737.6 offspring, 0.2040 d(-1), 1.2263 d(-1)). The high growth rates on these green manure crops show that they can serve as potential breeding sites for S. litura. Population projection demonstrated the rapid growth of S. litura on sesbania, sunn hemp, and rapeseed as well. Because most growers have traditionally ignored pest management in green manure fields, the mass emergence of S. litura in these fields may cause unexpected infestations in nearby vegetable, corn, and peanut crops. This study shows that the use of green manures as sources of nutrients should be critically reassessed and an area-wide pest management program should be instituted by taking the population of S. litura in green manure fields into consideration.

  6. MicroRNAome of Spodoptera frugiperda cells (Sf9) and its alteration following baculovirus infection.

    PubMed

    Mehrabadi, Mohammad; Hussain, Mazhar; Asgari, Sassan

    2013-06-01

    MicroRNAs (miRNAs) as small non-coding RNAs play important roles in many biological processes such as development, cell signalling and immune response. Studies also suggest that miRNAs are important in host-virus interactions where the host limits virus infection by differentially expressing miRNAs that target essential viral genes. Here, we identified conserved and new miRNAs from Spodoptera frugiperda cells (Sf9) using a combination of deep sequencing and bioinformatics as well as experimental approaches. S. frugiperda miRNAs share common features of miRNAs in other organisms, such as uracil (U) at the 5' end of miRNA. The 5' ends of the miRNAs were more conserved than the 3' ends, revealing evolutionary protection of the seed region in miRNAs. The predominant miRNAs were found to be conserved among arthropods. The majority of homologous miRNAs were found in Bombyx mori, with 76 of the 90 identified miRNAs. We found that seed shifting and arm switching have happened in this insect's miRNAs. Expression levels of the majority of miRNAs changed following baculovirus infection. Results revealed that baculovirus infection mainly led to an overall suppression of cellular miRNAs. We found four different genes being regulated by sfr-miR-184 at the post-transcriptional level. The data presented here further support conservation of miRNAs in insects and other organisms. In addition, the results reveal a differential expression of host miRNAs upon baculovirus infection, suggesting their potential roles in host-virus interactions. Seed shifting and arm switching happened during evolution of miRNAs in different insects and caused miRNA diversification, which led to changes in the target repository of miRNAs.

  7. Establishment of phagocytic cell lines from larval hemocytes of the beet armyworm, Spodoptera exigua.

    PubMed

    Chisa, Yasunaga-Aoki; Imanishi, Shigeo; Iiyama, Kazuhiro; Kawarabata, Takeshi

    2004-01-01

    Hemolymph was taken from beet armyworm (Spodoptera exigua) larvae and a new hemocyte cell line (SeHe920-1a) was established by supplementing the culture medium with a reduced form of glutathione to avoid the activation of prophenoloxidase cascade. To evaluate the phagocytic ability of the SeHe920-1a cells, polystyrene microspheres of two sizes (6.14 +/- 0.45 microm and 2.84 +/- 0.14 microm in diameter) and inactivated spores of an entomopathogenic microsporidium, Vairimorpha sp. NIS M12 (5.10 +/- 0.21 microm x 2.00 +/- 0.11 microm), were introduced into the cell culture. The SeHe920-1a cells had higher phagocytic ability than other lepidopteran cell lines that were not derived from the hemocytes. When microsporidian spores were inoculated, 27% of SeHe920-1a cells were observed to take up spores (average 1.7 spores per cell). By cloning SeHe920-1a cells, 12 cell lines were established and designated SeHe920Y1 to SeHe920Y12. In comparison with the parental cell line, phagocytic activity was enhanced in SeHe920Y6, SeHe920Y10, and SeHe920Y11 cell lines and especially in the SeHe920Y7 cell line, where approximately 50% of cells were phagocytic and the average number of microsporidian spores engulfed per cell was twice that of the SeHe920-1a cell line.

  8. Effects of Pyriproxyfen on Female Reproduction in the Common Cutworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae).

    PubMed

    Xu, Qi; Tang, Bin; Zou, Qi; Zheng, Huizhen; Liu, Xiaojun; Wang, Shigui

    2015-01-01

    The common cutworm, Spodoptera litura, is a rapidly reproducing pest of numerous agricultural ecosystems worldwide. The use of pesticides remains the primary means for controlling S. litura, despite their negative ecological impact and potential threat to human health. The use of exogenous hormone analogs may represent an alternative to insecticides. Juvenile hormones (JHs) play an important role in the reproductive systems of female insects, but the effects of pyriproxyfen, a JH analog, on reproduction in S. litura were poorly understood. In this paper, we topically treated the newly emerged females with 20, 60, or 100 μg of pyriproxyfen to determine its effects on reproduction. Then, we examined the expression of vitellogenin (Vg) and three hormone receptors, USP, HR3, and EcR, using quantitative reverse transcription and real-time polymerase chain reaction (qRT-PCR), and found that pyriproxyfen up-regulated the expression of Vg, USP, and HR3, whereas the expression of EcR was unaffected. An analysis of fecundity showed that the peak oviposition day, lifespan, and oviposition period were progressively shortened as the pyriproxyfen dosage increased. We also found that pyriproxyfen decreased egg laying amount, whereas the number of mature eggs that remained in the ovarioles of dead females increased as the pyriproxyfen dosage increased. We examined oocytes using transmission electron microscopy and found that treatment with 100 μg of pyriproxyfen increased the metabolism by increasing the amount of rough endoplasmic reticulum and mitochondria in the primary oocytes. Our results suggest that the topical application of pyriproxyfen on newly emerged females can efficiently reduce reproduction in S. litura and may represent an alternative to the use of insecticides for controlling the agricultural pest.

  9. Characterization of putative virulence factors of Serratia marcescens strain SEN for pathogenesis in Spodoptera litura.

    PubMed

    Aggarwal, Chetana; Paul, Sangeeta; Tripathi, Vishwas; Paul, Bishwajeet; Khan, Md Aslam

    2017-02-01

    Two Serratia marcescens strains, SEN and ICC-4, isolated from diseased insect cadavers were observed to differ considerably in their virulence towards Spodoptera litura. The present study was aimed to characterize the possible virulence factors present in the virulent Serratia marcescens strain SEN. Both the S. marcescens strains were evaluated for the presence of various lytic enzymes such as chitinase, lipase, protease and phospholipase. The virulent S. marcescens strain SEN was observed to possess considerably higher activity of chitinase and protease enzymes; activity of phospholipase enzyme was also higher. Although, all the three toxin genes shlA, phlA and swr could be detected in both the S. marcescens strains, there was a higher expression of these genes in the virulent strain SEN. S. marcescens strain ICC-4 showed greater reduction in overall growth yield in the post-exponential phase in the presence of midgut juice and hemolymph of S. litura larvae, as compared to S. marcescens strain SEN. Proliferation of the S. marcescens strain SEN was also considerably higher in foregut, midgut and hemolymph of S. litura larvae, as compared to strain ICC-4. Peritrophic membrane treated with broth culture of the S. marcescens strain SEN showed higher damage as compared to strain ICC-4. The peritrophic membrane of larvae fed on diet treated with the virulent strain showed considerable damage while the peritrophic membrane of larvae fed on diet treated with the non-virulent strain showed no damage. This is the first report documenting the fate of ingested S. marcescens in S. litura gut and the relative expression of toxin genes from two S. marcescens strains differing in their virulence towards S. litura. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Fitness costs associated with field-evolved resistance to Bt maize in Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Jakka, S R K; Knight, V R; Jurat-Fuentes, J L

    2014-02-01

    Increasing adoption of transgenic crops expressing cry toxin genes from Bacillus thuringiensis (Bt crops) represents an augmented risk for development of insect resistance. While fitness costs can greatly influence the rate of resistance evolution, most available data related to Bt resistance have been obtained from laboratory-selected insect strains. In this article, we test the existence of fitness costs associated with high levels of field-evolved resistance to Bt maize event TC1507 in a strain of Spodoptera frugiperda (JE Smith) originated from maize fields in Puerto Rico. Fitness costs in resistant S. frugiperda were evaluated by comparing biological performance to susceptible insects when reared on meridic diet, maize or soybean leaf tissue, or cotton reproductive tissues. Parameters monitored included larval survival, larval and pupal weights, developmental time (larval and pupal), adult longevity, reproductive traits (fecundity and fertility), and sex ratio. We found that all monitored parameters were influenced to a similar extent by the host, independently of susceptibility to Bt maize. The only parameter that significantly differed between strains for all hosts was a longer larval developmental period in resistant S. frugiperda, which resulted in emergence asynchrony between susceptible and resistant adults. To test the relevance of fitness costs in resistant S. frugiperda, we performed a selection experiment to monitor the stability of resistance in a heterogeneous strain through 12 generations of rearing on meridic diet. Our data demonstrate lack of fitness costs relevant to stability of field-evolved resistance to Bt maize and help explain reported stability of field-evolved resistance in Puerto Rican populations of S. frugiperda.

  11. Increased efficacy and extended shelf life of spinosad formulated in phagostimulant granules against Spodoptera frugiperda.

    PubMed

    Tamez-Guerra, Patricia; Tamayo-Mejía, Fernando; Gomez-Flores, Ricardo; Rodríguez-Padilla, Cristina; Damas, Gabriela; Tamez-Guerra, Reyes S; Ek-Ramos, Maria J; Williams, Trevor

    2017-06-30

    Spinosad is recommended for control of Spodoptera frugiperda (J.E. Smith) larvae; its application with phagostimulants may reduce the quantity of active ingredient required for effective pest control. Spinosad (Tracer®) was formulated in maize flour matrix granules and three field tests compared 10-100 ppm a.i. granules (equivalent to 0.24-2.4 g a.i. ha(-1) ) with Tracer as an aqueous spray (200 ppm a.i.; 60 g a.i. ha(-1) ), and the recommended application rates of Bacillus thuringiensis, a chemical and an untreated controls were performed. The 100 ppm spinosad granules resulted in similar S. frugiperda mortality compared with the chemical treatments in all three field trials, and resulted in a significantly higher maize grain yield compared with unformulated and control treatments (4141 vs. 2857 and 2407 kg ha(-1) , respectively) that was similar to the chemical treatment (3778 kg ha(-1) ). Bioassays of granules stored at room and cold temperatures showed that after 5 years, ∼ 70% of the original activity remained (OAR) of spinosad when formulated as granules. Nevertheless, after 9 years, efficacy was reduced (26.2% and 48.5% OAR) at both room (25 °C) and refrigerated temperatures (4 °C). Spinosad, in the granular phagostimulant formulations evaluated in this study, had advantages measured as high efficacy and long shelf life. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. The expression of Spodoptera exigua P450 and UGT genes: tissue specificity and response to insecticides.

    PubMed

    Hu, Bo; Zhang, Shu-Heng; Ren, Miao-Miao; Tian, Xiang-Rui; Wei, Qi; Mburu, David Kibe; Su, Jian-Ya

    2017-09-07

    Cytochrome P450 and UDP-glucosyltransferase as phase I and phase II metabolism enzymes respectively, play vital roles in the breakdown of endobiotics and xenobiotics. Insects can increase the expression of detoxification enzymes to cope with the stress from xenobiotics including insecticides. However, the molecular mechanisms for insecticide detoxification in Spodoptera exigua remain elusive, and the genes conferred insecticide metabolisms in this species are less reported. In this study, 68 P450 and 32 UGT genes were identified. Phylogenetic analysis showed gene expansions in CYP3 and CYP4 clans of P450 genes and UGT33 family of this pest. P450 and UGT genes exhibited specific tissue expression pattern. Insecticide treatments in fat body cells of S. exigua revealed that the expression levels of P450 and UGT genes were significantly influenced by challenges of abamectin, lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb respectively. Multiple genes for detoxification were affected in expression levels after insecticide exposures. The results demonstrated that lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb induced similar response in the expression of P450 and UGT genes in fat body cells, eight P450 genes and four UGT genes were co-up-regulated significantly, and no or only a few CYP/UGT genes were down-regulated significantly by these four insecticides. However, abamectin triggered a distinct response for P450 and UGT gene expression, more P450 and UGT genes were down-regulated by abamectin than by other four compounds. In conclusion, P450 and UGT genes from S. exigua were identified, and difference responses to abamectin suggest a different mechanism for insecticide detoxification. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. Differential immunosuppression by Campoletis chlorideae eggs and ichnovirus in larvae of Helicoverpa armigera and Spodoptera exigua.

    PubMed

    Han, Li-Bin; Yin, Li-Hong; Huang, Ling-Qiao; Wang, Chen-Zhu

    2015-09-01

    The ichneumonid wasp, Campoletis chlorideae Uchida, successfully develops in the cotton bollworm Helicoverpa armigera (Hübner), but rarely survives in the beet armyworm Spodoptera exigua (Hübner) due to the encapsulation by host immunity. In this study, we investigated the role of C. chlorideae ichnovirus (CcIV) and eggs in the evasion of the host immune system. Washed eggs of different types, immature, mature, newly laid, or pretreated with protease K, were injected alone or with the calyx fluid containing CcIV into the larvae of H. armigera and S. exigua. In H. armigera, when injected with washed eggs alone, only 9.5% of the mature eggs were encapsulated at 24h post-injection. This is much lower than that of the immature eggs (100%), mature eggs pretreated with protease K (100%) and newly laid eggs (54.4%). No encapsulation was observed when the washed eggs were co-injected with calyx fluid at 24h post-injection. Conversely, the eggs in all treatments were encapsulated in S. exigua. Electron microscopic observations of parasitoid eggs showed structural differences between the surfaces of the mature and other kinds of eggs. The injected CcIV decreased the numbers of host hemocytes and suppressed the spreading ability of plasmatocytes and granulocytes in H. armigera, but had little effect on the hemocytes from S. exigua. In conclusion, the C. chlorideae egg provides a passive protection against encapsulation by itself, and CcIV supplies an active protection through disrupting host immune responses. These coordinated protections are host-specific, implying their role in host range determination. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Demography and Consumption of Spodoptera litura (Lepidoptera: Noctuidae) Reared on Cabbage and Taro.

    PubMed

    Tuan, Shu-Jen; Yeh, Chih-Chun; Atlihan, Remzi; Chi, Hsin; Tang, Li-Cheng

    2016-04-01

    Spodoptera litura (F.) causes considerable economic damage to multiple agro-crops annually in many countries. In this study, the demography of S. litura reared on cabbage and taro was investigated using the age-stage, two-sex life table at 25±1°C, 60±10% relative humidity, and a photoperiod of 12: 12 (L:D) h. Our results showed that the net reproductive rate, intrinsic rate, and finite rate of population increase on cabbage (1893.1 offspring, 0.2374 d(−1), and 1.2679 d(−1)) were all not significantly different from those on taro (1361.0 offspring, 0.2298 d(−1), and 1.2584 d(−1)). The net consumption rate on cabbage (439.1 cm2) was, however, three times higher than that on taro (141.7 cm2). According to the population parameters, both cabbage and taro are suitable host plants for S. litura. When both the population growth rate and the consumption rate were taken into consideration, the finite consumption rate on cabbage (ω=3.8054) was significantly higher than that on taro (ω=1.3184). In Taiwan, taro and cabbage are commonly planted in adjacent farm plots, with taro being grown from March to November and cabbage from October to April. Because of the overlapping growth periods of the two crops, S. litura can easily propagate throughout the year by switching between the adjacent crops during the overlap periods. Pest management strategies for controlling S. litura must be thoroughly reevaluated based on ecological characteristics, including its life table and consumption rate on its major host plants.

  15. Identification and functional characterization of sex pheromone receptors in beet armyworm Spodoptera exigua (Hübner).

    PubMed

    Liu, Chengcheng; Liu, Yang; Walker, William B; Dong, Shuanglin; Wang, Guirong

    2013-08-01

    In moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (ORNs) on the antennae. Four candidate pheromone receptors (PR) with seven transmembrane domains were identified by homology cloning from the antennae of Spodoptera exigua (Sexi). Phylogenetic analyses reveal that all four odorant receptors (OR) belong to pheromone receptor subtypes. Expression patterns revealed that PRs were male-specific in the antenna except for SexiOR11, which was female antenna-biased. Functional analyses of these PRs were conducted using heterologous expression in Xenopus oocytes. SexiOR13 and SexiOR16 were all broadly activated by multiple pheromone components. SexiOR13 responded robustly to the critical pheromone component, Z9, E12-14:OAc and the minor pheromone component, Z9-14:OAc at a concentration of 10(-4) M. Dose-response studies indicate that SexiOR13 was approximately 4 times more sensitive to Z9,E12-14:OAc (EC50 = 3.158 × 10(-6) M) compared to Z9-14:OAc (EC50 = 1.203 × 10(-5) M). While, SexiOR16 responded robustly to the secondary pheromone component Z9-14:OH with high sensitivity (EC50 = 9.690 × 10(-7) M). However, similar tests of the five pheromones with SexiOR6 and SexiOR11 failed to elicit any response. These results provide basic knowledge to further advance research on the molecular mechanisms of pheromone reception. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Potential of Trap Crops for Integrated Management of the Tropical Armyworm, Spodoptera litura in Tobacco

    PubMed Central

    Zhou, Zhongshi; Chen, Zepeng; Xu, Zaifu

    2010-01-01

    The tropical armyworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae), is an important pest of tobacco, Nicotiana tabacum L. (Solanales: Solanaceae), in South China that is becoming increasingly resistant to pesticides. Six potential trap crops were evaluated to control S. litura on tobacco. Castor bean, Ricinus communis L. (Malpighiales: Euphorbiaceae), and taro, Colocasia esculenta (L.) Schott (Alismatales: Araceae), hosted significantly more S. litura than peanut, Arachis hypogaea L. (Fabales: Fabaceae), sweet potato, Ipomoea batata Lam. (Solanales: Convolvulaceae) or tobacoo in a greenhouse trial, and tobacco field plots with taro rows hosted significantly fewer S. litura than those with rows of other trap crops or without trap crops, provided the taro was in a fast-growing stage. When these crops were grown along with eggplant, Solanum melongena L. (Solanales: Solanaceae), and soybean, Glycines max L. (Fabales: Fabaceae), in separate plots in a randomized matrix, tobacco plots hosted more S. litura than the other crop plots early in the season, but late in the season, taro plots hosted significantly more S. litura than tobacco, soybean, sweet potato, peanut or eggplant plots. In addition, higher rates of S. litura parasitism by Microplitis prodeniae Rao and Chandry (Hymenoptera: Bracondidae) and Campoletis chlorideae Uchida (Ichnumonidae) were observed in taro plots compared to other crop plots. Although taro was an effective trap crop for managing S. litura on tobacco, it did not attract S. litura in the seedling stage, indicating that taro should either be planted 20–30 days before tobacco, or alternative control methods should be employed during the seedling stage. PMID:20874598

  17. Genetic Structure of a Spodoptera frugiperda Nucleopolyhedrovirus Population: High Prevalence of Deletion Genotypes

    PubMed Central

    Simón, Oihane; Williams, Trevor; López-Ferber, Miguel; Caballero, Primitivo

    2004-01-01

    A Nicaraguan field isolate (SfNIC) of Spodoptera frugiperda nucleopolyhedrovirus was purified by plaque assay on Sf9 cells. Nine distinct genotypes, A to I, were identified by their restriction endonuclease profiles. Variant SfNIC-B was selected as the standard because its restriction profile corresponded to that of the wild-type isolate. Physical maps were generated for each of the variants. The differences between variants and the SfNIC-B standard were confined to the region between map units 9 and 32.5. This region included PstI-G, PstI-F, PstI-L, PstI-K and EcoRI-L fragments. Eight genotypes presented a deletion in their genome compared with SfNIC-B. Occlusion body-derived virions of SfNIC-C, -D and -G accounted for 41% of plaque-purified clones. These variants were not infectious per os but retained infectivity by injection into S. frugiperda larvae. Median 50% lethal concentration values for the other cloned genotypes were significantly higher than that of the wild type. The variants also differed in their speed of kill. Noninfectious variants SfNIC-C and -D lacked the pif and pif-2 genes. Infectivity was restored to these variants by plasmid rescue with a plasmid comprising both pif and pif-2. Transcription of an SfNIC-G gene was detected by reverse transcription-PCR in insects, but no fatal disease developed. Transcription was not detected in SfNIC-C or -D-inoculated larvae. We conclude that the SfNIC population presents high levels of genetic diversity, localized to a 17-kb region containing pif and pif-2, and that interactions among complete and deleted genotypic variants will likely influence the capacity of this virus to control insect pests. PMID:15345446

  18. Identification and Characterization of Candidate Chemosensory Gene Families from Spodoptera exigua Developmental Transcriptomes.

    PubMed

    Liu, Nai-Yong; Zhang, Ting; Ye, Zhan-Feng; Li, Fei; Dong, Shuang-Lin

    2015-01-01

    Insect chemosensory genes have been considered as potential molecular targets to develop alternative strategies for pest control. However, in Spodoptera exigua, a seriously polyphagous agricultural pest, only a small part of such genes have been identified and characterized to date. Here, using a bioinformatics screen a total of 79 chemosensory genes were identified from a public transcriptomic data of different developmental stages (eggs, 1st to 5th instar larvae, pupae, female and male adults), including 34 odorant binding proteins (OBPs), 20 chemosensory proteins (CSPs), 22 chemosensory receptors (10 odorant receptors (ORs), six gustatory receptors (GRs) and six ionotropic receptors (IRs)) and three sensory neuron membrane proteins (SNMPs). Notably, a new group of lepidopteran SNMPs (SNMP3 group) was found for the first time in S. exigua, and confirmed in four other moth species. Further, reverse transcription PCR (RT-PCR) and quantitative real time PCR (qPCR) were employed respectively to validate the sequences and determine the expression patterns of 69 identified chemosensory genes regarding to sexes, tissues and stages. Results showed that 67 of these genes could be detected and reconstructed in at least one tissue tested. Further, 60 chemosensory genes were expressed in adult antennae and 52 in larval heads with the antennae, whereas over half of the genes were also detected in non-olfactory tissues like egg and thorax. Particularly, S. exigua OBP2 showed a predominantly larval head-biased expression, and functional studies further indicated its potentially olfactory roles in guiding food searching of larvae. This work suggests functional diversities of S. exigua chemosensory genes and could greatly facilitate the understanding of olfactory system in S. exigua and other lepidopteran species.

  19. SfDronc, an initiator caspase involved in apoptosis in the fall armyworm Spodoptera frugiperda.

    PubMed

    Huang, Ning; Civciristov, Srgjan; Hawkins, Christine J; Clem, Rollie J

    2013-05-01

    Initiator caspases are the first caspases that are activated following an apoptotic stimulus, and are responsible for cleaving and activating downstream effector caspases, which directly cause apoptosis. We have cloned a cDNA encoding an ortholog of the initiator caspase Dronc in the lepidopteran insect Spodoptera frugiperda. The SfDronc cDNA encodes a predicted protein of 447 amino acids with a molecular weight of 51 kDa. Overexpression of SfDronc induced apoptosis in Sf9 cells, while partial silencing of SfDronc expression in Sf9 cells reduced apoptosis induced by baculovirus infection or by treatment with UV or actinomycin D. Recombinant SfDronc exhibited several expected biochemical characteristics of an apoptotic initiator caspase: 1) SfDronc efficiently cleaved synthetic initiator caspase substrates, but had very little activity against effector caspase substrates; 2) mutation of a predicted cleavage site at position D340 blocked autoprocessing of recombinant SfDronc and reduced enzyme activity by approximately 10-fold; 3) SfDronc cleaved the effector caspase Sf-caspase-1 at the expected cleavage site, resulting in Sf-caspase-1 activation; and 4) SfDronc was strongly inhibited by the baculovirus caspase inhibitor SpliP49, but not by the related protein AcP35. These results indicate that SfDronc is an initiator caspase involved in caspase-dependent apoptosis in S. frugiperda, and as such is likely to be responsible for the initiator caspase activity in S. frugiperda cells known as Sf-caspase-X. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Cry1F resistance in fall armyworm Spodoptera frugiperda: single gene versus pyramided Bt maize.

    PubMed

    Huang, Fangneng; Qureshi, Jawwad A; Meagher, Robert L; Reisig, Dominic D; Head, Graham P; Andow, David A; Ni, Xinzi; Kerns, David; Buntin, G David; Niu, Ying; Yang, Fei; Dangal, Vikash

    2014-01-01

    Evolution of insect resistance to transgenic crops containing Bacillus thuringiensis (Bt) genes is a serious threat to the sustainability of this technology. However, field resistance related to the reduced efficacy of Bt maize has not been documented in any lepidopteran pest in the mainland U.S. after 18 years of intensive Bt maize planting. Here we report compelling evidence of field resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith), to Cry1F maize (TC 3507) in the southeastern region of the U.S. An F2 screen showed a surprisingly high (0.293) Cry1F resistance allele frequency in a population collected in 2011 from non-Bt maize in south Florida. Field populations from non-Bt maize in 2012-2013 exhibited 18.8-fold to >85.4-fold resistance to purified Cry1F protein and those collected from unexpectedly damaged Bt maize plants at several locations in Florida and North Carolina had >85.4-fold resistance. In addition, reduced efficacy and control failure of Cry1F maize against natural populations of S. frugiperda were documented in field trials using Cry1F-based and pyramided Bt maize products in south Florida. The Cry1F-resistant S. frugiperda also showed a low level of cross-resistance to Cry1A.105 and related maize products, but not to Cry2Ab2 or Vip3A. The occurrence of Cry1F resistance in the U.S. mainland populations of S. frugiperda likely represents migration of insects from Puerto Rico, indicating the great challenges faced in achieving effective resistance management for long-distance migratory pests like S. frugiperda.

  1. Natural distribution of parasitoids of larvae of the fall armyworm, Spodoptera frugiperda, in Argentina.

    PubMed

    Gabriela Murúa, M; Molina-Ochoa, Jaime; Fidalgo, Patricio

    2009-01-01

    To develop a better understanding of the natural distribution of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), and to update the knowledge of the incidence of its complex of parasitoids. S. frugiperda, samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. S. frugiperda larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from S. frugiperda larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The S. frugiperda parasitoids collected were Campoletis grioti (Blanchard) (Hymenoptera: Ichneumonidae), Chelonus insularis (Cresson) (Hymenoptera: Braconidae), Archytas marmoratus (Townsend) (Diptera Tachinidae) and/or A. incertus (Macquart), Ophion sp. (Hymenoptera: Ichneumonidae), Euplectrus platyhypenae Howard (Hymenoptera: Eulophidae), and Incamyia chilensis (Aldrich) (Diptera Tachinidae). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae that were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. These results demonstrate that hymenopteran and dipteran parasitoids of S. frugiperda occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the S. frugiperda larval

  2. Juvenile hormone biosynthesis in the fall armyworm, Spodoptera frugiperda (Lepidoptera, Noctuidae).

    PubMed

    Range, Sebastian; Oeh, Uwe; Lorenz, Matthias W; Etzel, Winfried; Nauen, Ralf; Hoffmann, Klaus H

    2002-05-01

    The in vitro production of juvenile hormones (JH) was investigated by using corpora allata (CA) of larvae and corpora cardiaca-corpora allata (CC-CA) complexes of adult females of the fall armyworm Spodoptera frugiperda. In female moths, JH release was high compared to that in 5th and 6th instar larvae. Concentrations of 0.11-0.12 mM methionine, 180-200 mM Na(+), 5.8-8.3 mM K(+), 10-50 mM Ca(2+) and a pH range of 5.7-6.3 yielded optimal incorporation of L-[methyl-(3)H] methionine in vitro by CC-CA complexes. The highest hourly incorporation occurred during a 9-h incubation period following a 1.5-h lag-phase. JH release from CC-CA complexes of adult females was shown to be age-dependent with a peak value on day 2 (approx. 4 pmol h(-1) CA(-1)). By a combination of reversed phase (RP)- and normal phase (NP)-high performance liquid chromatography (HPLC), two major labelled products released by the complex were separated. One compound co-migrated with chemically synthesized JH II diol, the second compound with JH III diol. Only traces of JH II and III could be detected in some samples. Gland extracts also contained both the major radiolabelled products. Double labelling experiments using [3H]methionine and [14C]acetate confirmed their de novo synthesis in CC-CA complexes of female moths. The nature of chemically synthesized reference JH III diol was proved by LC-MS (ESI mass spectrometry) and 1H-NMR (nuclear magnetic resonance spectroscopy).

  3. Natural Distribution of Parasitoids of Larvae of the Fall Armyworm, Spodoptera frugiperda, in Argentina

    PubMed Central

    Gabriela Murúa, M.; Molina-Ochoa, Jaime; Fidalgo, Patricio

    2009-01-01

    To develop a better understanding of the natural distribution of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), and to update the knowledge of the incidence of its complex of parasitoids. S. frugiperda, samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. S. frugiperda larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from S. frugiperda larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The S. frugiperda parasitoids collected were Campoletis grioti (Blanchard) (Hymenoptera: Ichneumonidae), Chelonus insularis (Cresson) (Hymenoptera: Braconidae), Archytas marmoratus (Townsend) (Diptera Tachinidae) and/or A. incertus (Macquart), Ophion sp. (Hymenoptera: Ichneumonidae), Euplectrus platyhypenae Howard (Hymenoptera: Eulophidae), and Incamyia chilensis (Aldrich) (Diptera Tachinidae). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae that were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. These results demonstrate that hymenopteran and dipteran parasitoids of S. frugiperda occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the S. frugiperda larval

  4. Cry1F Resistance in Fall Armyworm Spodoptera frugiperda: Single Gene versus Pyramided Bt Maize

    PubMed Central

    Huang, Fangneng; Qureshi, Jawwad A.; Meagher, Robert L.; Reisig, Dominic D.; Head, Graham P.; Andow, David A.; Ni, Xinzi; Kerns, David; Buntin, G. David; Niu, Ying; Yang, Fei; Dangal, Vikash

    2014-01-01

    Evolution of insect resistance to transgenic crops containing Bacillus thuringiensis (Bt) genes is a serious threat to the sustainability of this technology. However, field resistance related to the reduced efficacy of Bt maize has not been documented in any lepidopteran pest in the mainland U.S. after 18 years of intensive Bt maize planting. Here we report compelling evidence of field resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith), to Cry1F maize (TC 3507) in the southeastern region of the U.S. An F2 screen showed a surprisingly high (0.293) Cry1F resistance allele frequency in a population collected in 2011 from non-Bt maize in south Florida. Field populations from non-Bt maize in 2012–2013 exhibited 18.8-fold to >85.4-fold resistance to purified Cry1F protein and those collected from unexpectedly damaged Bt maize plants at several locations in Florida and North Carolina had >85.4-fold resistance. In addition, reduced efficacy and control failure of Cry1F maize against natural populations of S. frugiperda were documented in field trials using Cry1F-based and pyramided Bt maize products in south Florida. The Cry1F-resistant S. frugiperda also showed a low level of cross-resistance to Cry1A.105 and related maize products, but not to Cry2Ab2 or Vip3A. The occurrence of Cry1F resistance in the U.S. mainland populations of S. frugiperda likely represents migration of insects from Puerto Rico, indicating the great challenges faced in achieving effective resistance management for long-distance migratory pests like S. frugiperda. PMID:25401494

  5. Genetic and biological variation among nucleopolyhedrovirus isolates from the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Rowley, Daniel L; Farrar, Robert R; Blackburn, Michael B; Harrison, Robert L

    2010-06-01

    A PCR-based method was used to identify and distinguish among 40 uncharacterized nucleopolyhedrovirus (NPV) isolates from larvae of the moth Spodoptera frugiperda that were part of an insect virus collection. Phylogenetic analysis was carried out with sequences amplified from two strongly conserved loci (polh and lef-8) from the 40 isolates in the collection and from eight previously studied S. frugiperda NPV (SfMNPV) isolates. To further distinguish these isolates, analysis was also carried out with sequences from two less-conserved loci, hr4 and hr5. Phylogenetic inference from the sequence data could distinguish among several of the individual isolates and between different groups of isolates from Georgia (USA) and Colombia, South America. A stronger degree of bootstrap support for the phylogenetic trees was obtained with the hr4 and hr5 homologous repeat sequences. Sequencing and phylogenetic analysis detected a relatively high degree of larva-to-larva sequence divergence occurring among isolates of SfMNPV collected from the same field in Missouri, USA. Restriction endonuclease analysis of viral DNA from larvae infected with five isolates from Georgia, Missouri, Louisiana, Florida (USA), and Colombia allowed for further comparison with other previously reported isolates of SfMNPV. Bioassays with these five geographically distinct isolates detected minor differences in virulence. This study highlights the use of PCR to rapidly distinguish and characterize large numbers of historical baculovirus isolates from the same host using minimal quantities of material, and the use of sequences from homologous repeat regions to distinguish closely related isolates of the same NPV species.

  6. Cloning of the heat shock protein 90 and 70 genes from the beet armyworm, Spodoptera exigua, and expression characteristics in relation to thermal stress and development

    USDA-ARS?s Scientific Manuscript database

    Two full-length complementary DNAs (cDNAs) of heat shock protein (HSP) genes (Se-hsp90 and Se-hsp70) were cloned from the beet armyworm, Spodoptera exigua, and their expression was investigated in relation to cold shock, heat shock, and development. The open reading frames of Se-hsp90 and Sehsp70 ar...

  7. A novel cytochrome P450 CYP6AB14 gene in Spodoptera litura (Lepidoptera: Noctuidae) and its potential role in plant allelochemical detoxification

    USDA-ARS?s Scientific Manuscript database

    Cytochrome P450 monooxygenases (P450) play a prominent role in the adaptation of insects to host plant chemical defenses. To investigate the potential role of P450s in adaptation of the lepidopteran pest Spodoptera litura to host plant allelochemicals, an expressed sequence data set derived from 6th...

  8. Metatranscriptomic Analysis of Larval Guts from Field-Collected and Laboratory-Reared Spodoptera frugiperda from the South American Subtropical Region

    PubMed Central

    Cabrera, Natalia A.; Virla, Eduardo G.

    2015-01-01

    This is the first study to report a high-throughput approach integrating gene expression data from Spodoptera frugiperda guts and their associated metatranscriptomes. Our datasets provide information on the potential effects of environmental conditions on the expression profile of S. frugiperda larval guts, their associated metatranscriptome, and putative interactions between them. PMID:26184938

  9. A novel cytochrome P450 CYP6AB14 gene in spodoptera litura (Lepidoptera: Noctuidae) and its potential role in plant allelochemical detoxification

    USDA-ARS?s Scientific Manuscript database

    Cytochrome P450 monooxygenases (P450) play a prominent role in the adaptation of insects to host plant chemical defenses. To investigate the potential role of P450s in adaptation of the lepidopteran pest Spodoptera litura to host plant allelochemicals, an expressed sequence data set derived from 6th...

  10. F2 screen for resistance to Bacillus thuringiensis Cry2Ab2-maize in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) from the southern United States

    USDA-ARS?s Scientific Manuscript database

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target of transgenic maize and cotton expressing Bacillus thuringiensis (Bt) proteins in both North and South America. In 2013 and 2014, a total of 215 F2 two-parent families of S. frugiperda were established usin...

  11. Feeding Practices and NEC

    PubMed Central

    Ramani, Manimaran

    2012-01-01

    Synopsis Necrotizing enterocolitis (NEC) is a multifactorial disorder that primarily affects premature infants. Human milk as compared to formula reduces the incidence of NEC. Feeding practices such as minimal enteral nutrition (versus complete fasting) before progressive advancement of feeds, early introduction of feeds (before day 4 of life as compared to later), and a more rapid advancement of feeds (30–35 ml/kg/day as compared to 15–20 ml/kg/day) do not increase the incidence of NEC in preterm infants. There is no evidence supporting continuous over intermittent tube feedings in preterm infants. In a feed-intolerant preterm infant without any other clinical and radiological evidence of NEC, minimal enteral nutrition rather than complete suspension of enteral feeding may be an alternative. Human milk-based fortifier as compared to bovine-based fortifier may reduce the incidence of NEC but additional studies are required. PMID:23415260

  12. Interaction of Bacillus thuringiensis vegetative insecticidal protein with ribosomal S2 protein triggers larvicidal activity in Spodoptera frugiperda.

    PubMed

    Singh, Gatikrushna; Sachdev, Bindiya; Sharma, Nathilal; Seth, Rakesh; Bhatnagar, Raj K

    2010-11-01

    Vegetative insecticidal protein (Vip3A) is synthesized as an extracellular insecticidal toxin by certain strains of Bacillus thuringiensis. Vip3A is active against several lepidopteran pests of crops. Polyphagous pest, Spodoptera frugiperda, and its cell line Sf21 are sensitive for lyses to Vip3A. Screening of cDNA library prepared from Sf21 cells through yeast two-hybrid system with Vip3A as bait identified ribosomal protein S2 as a toxicity-mediating interacting partner protein. The Vip3A-ribosomal-S2 protein interaction was validated by in vitro pulldown assays and by RNA interference-induced knockdown experiments. Knockdown of expression of S2 protein in Sf21 cells resulted in reduced toxicity of the Vip3A protein. These observations were further extended to adult fifth-instar larvae of Spodoptera litura. Knockdown of S2 expression by injecting corresponding double-stranded RNA resulted in reduced mortality of larvae to Vip3A toxin. Intracellular visualization of S2 protein and Vip3A through confocal microscopy revealed their interaction and localization in cytoplasm and surface of Sf21 cells.

  13. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for uranium...

  14. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for uranium...

  15. Secretions from the ventral eversible gland of Spodoptera exigua caterpillars activate defense-related genes and induce emission of volatile organic compounds in tomato, Solanum lycopersicum.

    PubMed

    Zebelo, Simon; Piorkowski, Jill; Disi, Joseph; Fadamiro, Henry

    2014-05-20

    Plant induced defense against herbivory are generally associated with metabolic costs that result in the allocation of photosynthates from growth and reproduction to the synthesis of defense compounds. Therefore, it is essential that plants are capable of sensing and differentiating mechanical injury from herbivore injury. Studies have shown that oral secretions (OS) from caterpillars contain elicitors of induced plant responses. However, studies that shows whether these elicitors originated from salivary glands or from other organs associated with feeding, such as the ventral eversible gland (VEG) are limited. Here, we tested the hypothesis that the secretions from the VEG gland of Spodoptera exigua caterpillars contain elicitors that induce plant defenses by regulating the expression of genes involved in the biosynthesis of volatile organic compounds (VOCs) and other defense-related genes. To test this hypothesis, we quantified and compared the activity of defense-related enzymes, transcript levels of defense-related genes and VOC emission in tomato plants damaged by S. exigua caterpillars with the VEG intact (VEGI) versus plants damaged by caterpillars with the VEG ablated (VEGA). The quantified defense-related enzymes (i.e. peroxidase, polyphenol oxidase, and lipoxigenase) were expressed in significantly higher amounts in plants damaged by VEGI caterpillars than in plants damaged by VEGA caterpillars. Similarly, the genes that encode for the key enzymes involved in the biosynthesis of jasmonic acid and terpene synthase genes that regulate production of terpene VOCs, were up-regulated in plants damaged by VEGI caterpillars. Moreover, the OS of VEGA caterpillars were less active in inducing the expression of defense genes in tomato plants. Increased emissions of VOCs were detected in the headspace of plants damaged by VEGI caterpillars compared to plants damaged by VEGA caterpillars. These results suggest that the VEG of S. exigua caterpillars contains elicitors

  16. Secretions from the ventral eversible gland of Spodoptera exigua caterpillars activate defense-related genes and induce emission of volatile organic compounds in tomato, Solanum lycopersicum

    PubMed Central

    2014-01-01

    Background Plant induced defense against herbivory are generally associated with metabolic costs that result in the allocation of photosynthates from growth and reproduction to the synthesis of defense compounds. Therefore, it is essential that plants are capable of sensing and differentiating mechanical injury from herbivore injury. Studies have shown that oral secretions (OS) from caterpillars contain elicitors of induced plant responses. However, studies that shows whether these elicitors originated from salivary glands or from other organs associated with feeding, such as the ventral eversible gland (VEG) are limited. Here, we tested the hypothesis that the secretions from the VEG gland of Spodoptera exigua caterpillars contain elicitors that induce plant defenses by regulating the expression of genes involved in the biosynthesis of volatile organic compounds (VOCs) and other defense-related genes. To test this hypothesis, we quantified and compared the activity of defense-related enzymes, transcript levels of defense-related genes and VOC emission in tomato plants damaged by S. exigua caterpillars with the VEG intact (VEGI) versus plants damaged by caterpillars with the VEG ablated (VEGA). Results The quantified defense-related enzymes (i.e. peroxidase, polyphenol oxidase, and lipoxigenase) were expressed in significantly higher amounts in plants damaged by VEGI caterpillars than in plants damaged by VEGA caterpillars. Similarly, the genes that encode for the key enzymes involved in the biosynthesis of jasmonic acid and terpene synthase genes that regulate production of terpene VOCs, were up-regulated in plants damaged by VEGI caterpillars. Moreover, the OS of VEGA caterpillars were less active in inducing the expression of defense genes in tomato plants. Increased emissions of VOCs were detected in the headspace of plants damaged by VEGI caterpillars compared to plants damaged by VEGA caterpillars. Conclusion These results suggest that the VEG of S. exigua

  17. Fractionator feed section

    SciTech Connect

    Sampath, V.R.; Bachmann, D.E.

    1993-07-27

    A fractionator feed section in a fractionator to which is fed a feed mixture comprising a vapor component and a liquid component and which fractionator comprises a tray above said feed section which passes liquid reflux to said feed section, said feed section comprising: (a) a downwardly extending, elongated first baffle; (b) a downwardly extending, elongated second baffle; (c) a seal pan below said first baffle and said second baffle, said seal pan comprising a seal pan mixture of liquids into which a portion of said first baffle and a portion of said second baffle extend to form a mixing zone; (d) a feed nozzle which introduces said liquid component and said vapor component downward into said mixing zone; and, (e) a trough which introduces said liquid reflux to said mixing zone, wherein said liquid component and said liquid reflux mix to form said seal pan mixture of liquids.

  18. Nanotoxicological Effects of SiO2 Nanoparticles on Spodoptera frugiperda Sf9 Cells.

    PubMed

    Santo-Orihuela, Pablo L; Foglia, Maria L; Targovnik, Alexandra M; Miranda, Maria V; Desimone, Martin F

    2016-01-01

    The application of silica nanoparticles (NPs) in the biomedical field experienced a great development. The driving forces for these and future developments are the possibility to design NPs with homogeneous size and structure amenable to specific grafting. Moreover, it is possible to tune the characteristics of the NPs to meet the requirements of each specific cell and desired application. Herein, we analyzed the effect of silica NPs of various sizes and surface charge on the viability of Spodoptera frugiperda cells (Sf9 cell line) with the aim of extending the knowledge of possible toxicity of the NPs in the environment and development of new tools for insect control. Moreover, these results will also contribute to develop more effective systems for gene vectors delivery and recombinant proteins expression. Bare silica NPs of 14 nm, 380 nm and 1430 nm as well as amine-modified silica NPs of 131 nm and 448 nm were obtained by the Stöber method. The NPs were characterized by DLS and zeta potential measurements. The cell viability was assessed by the MTT test. It was observed that the 14 nm NPs possess the highest toxic effect. Indeed, after 24 h, the viability of the cells exposed to the lower concentration of NPs (0.12 mg/ml) was about 40% of the value obtained for the control cells not exposed to NPs. Moreover, the exposure to other negative charged NPs also causes a lower activity when compared with the control. Alternatively, lower concentrations of positive charged NPs (i.e.: 0.12 or 0.6 mg/ml) demonstrated to stimulate the proliferation of the cells and higher concentrations (i.e.: 7.2 mg/ml) did not present significant differences with the control. In conclusion, we have demonstrated that the NPs possess an effect that is highly influenced by the size, charge and concentration. Although, silica NPs are being used in the biomedical field, these results contribute to further understanding the risk that could be associated to nanoparticles and how these can be

  19. Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize.

    PubMed

    Sousa, Fernanda F; Mendes, Simone M; Santos-Amaya, Oscar F; Araújo, Octávio G; Oliveira, Eugenio E; Pereira, Eliseu J G

    2016-01-01

    Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50-70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations

  20. Effects of four host plants on biology and food utilization of the cutworm, Spodoptera litura.

    PubMed

    Xue, Ming; Pang, Yun-Hong; Wang, Hong-Tao; Li, Qing-Liang; Liu, Tong-Xian

    2010-01-01

    Effects of four host plants, tobacco, Chinese cabbage, cowpea and sweet potato, on larval and pupal development and survival, and longevity and fecundity of adults of Spodoptera litura (F) (Lepidoptera: Noctuidae), were studied under laboratory conditions (26 degrees C, 60-80% RH), as was the utilization of the four host plants and adaptation on tobacco. All of the biological parameters included in the study were affected by the host plants. In a choice test, S. litura females oviposited most on Chinese cabbage, least on tobacco, and intermediate on cowpea and sweet potato. S. litura larvae developed differently on the four host plants, from shortest to longest in the following order: Chinese cabbage, cowpea, sweet potato, and tobacco. Pupal development was shorter on cowpea than on the other three host plants, and males generally developed longer than females. More females than males were found among emerged adults, and male adults lived 1-2 d longer than females. Larvae survived best on cowpea (81.6%), followed by Chinese cabbage (75.5%), then sweet potato (66.1%), and worst on tobacco (49.2%). Pupal survival rates were relatively high (91.4-95.9%) in all four host plant treatments, although that on sweet potato was lower than those on the other three host plants. Pupal weights on tobacco and sweet potato were similar, but both were lower than those on Chinese cabbage and cowpea. Generally, male pupae weighed less than female pupae. Numbers of eggs oviposited by female S. litura were highest on sweet potato, followed by those on cowpea, Chinese cabbage, and lowest on tobacco. Relative food consumption rate was highest on sweet potato, followed by that on cowpea, Chinese cabbage, and lowest on tobacco. In contrast, S. litura larvae that fed on tobacco had higher efficiency of conversion of digested food, highest efficiency of conversion of ingested food, and lowest approximate digestibility as compared with larvae that fed on other host plants. The potential

  1. Regioselective biotransformation of (+)- and (-)-citronellene by the larvae of common cutworm ( Spodoptera litura ).

    PubMed

    Miyazawa, Mitsuo; Marumoto, Shinsuke; Masuda, Atsunori; Kano, Haruki; Takechi, Hiromune

    2009-09-09

    Terpenoids, which have many biological activities and have occurred widely in nature, can be artificially synthesized. However, regioselective oxidation of terpenoids is difficult by chemical methods. In this study, (+)- and (-)-citronellene were biotransformed with Spodoptera litura to define the mechanism of metabolism of citronellene and gain a new natural terpenoid. (+)-Citronellene was converted to (2S,3S)-3,7-dimethyl-6-octene-1,2-diol and (2R,3S)-3,7-dimethyl-6-octene-1,2-diol (89.7%), (3S,6S)-(-)-3,7-dimethyl-1-octene-6,7-diol (3.8%), (3S)-(6E)-(+)-3,7-dimethyl-1,6-octadien-8-ol (4.2%), and (3S)-(6E)-(+)-3,7-dimethyl-1,6-octadien-8-oic acid (2.3%). In contrast, (-)-citronellene was converted to (2R,3R)-3,7-dimethyl-6-octene-1,2-diol and (2S,3R)-3,7-dimethyl-6-octene-1,2-diol (56.3%), (+)-iridan-7,8-diol (3.5%), and (3R)-(6E)-(-)-3,7-dimethyl-1,6-octadien-8-oic acid (40.2%). The main metabolic pathway of (+)- and (-)-citronellene by larvae of S. litura was oxidized at the terminal double bond and trans-allylic methyl position. Particularly on (+)-citronellene, the regioselective reaction was shown. On the oxidation of C-6, C-7, and C-8 positions, four new compounds (3S,6S)-(-)-3,7-dimethyl-1-octene-6,7-diol, (3S)-(6E)-(+)-3,7-dimethyl-1,6-octadien-8-oic acid, (+)-iridan-7,8-diol, and (3R)-(6E)-(-)-3,7-dimethyl-1,6-octadien-8-oic acid were produced in regioselective oxidation. It noted that stereoselective oxidation occurred between the enantiomers. The C-6 position was oxidized on the (+)-(3S) form, whereas cyclized and the C-7 position were oxidized on the (-)-(3R) form.

  2. Investigating the molecular mechanisms of organophosphate and pyrethroid resistance in the fall armyworm Spodoptera frugiperda.

    PubMed

    Carvalho, Renato A; Omoto, Celso; Field, Linda M; Williamson, Martin S; Bass, Chris

    2013-01-01

    The fall armyworm Spodoptera frugiperda is an economically important pest of small grain crops that occurs in all maize growing regions of the Americas. The intensive use of chemical pesticides for its control has led to the selection of resistant populations, however, to date, the molecular mechanisms underlying resistance have not been characterised. In this study the mechanisms involved in the resistance of two S. frugiperda strains collected in Brazil to chlorpyrifos (OP strain) or lambda-cyhalothrin (PYR strain) were investigated using molecular and genomic approaches. To examine the possible role of target-site insensitivity the genes encoding the organophosphate (acetylcholinesterase, AChE) and pyrethroid (voltage-gated sodium channel, VGSC) target-site proteins were PCR amplified. Sequencing of the S. frugiperda ace-1 gene identified several nucleotide changes in the OP strain when compared to a susceptible reference strain (SUS). These result in three amino acid substitutions, A201S, G227A and F290V, that have all been shown previously to confer organophosphate resistance in several other insect species. Sequencing of the gene encoding the VGSC in the PYR strain, identified mutations that result in three amino acid substitutions, T929I, L932F and L1014F, all of which have been shown previously to confer knockdown/super knockdown-type resistance in several arthropod species. To investigate the possible role of metabolic detoxification in the resistant phenotype of the OP and PYR stains all EST sequences available for S. frugiperda were used to design a gene-expression microarray. This was then used to compare gene expression in the resistant strains with the susceptible reference strain. Members of several gene families, previously implicated in metabolic resistance in other insects were found to be overexpressed in the resistant strains including glutathione S-transferases, cytochrome P450s and carboxylesterases. Taken together these results provide

  3. Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize

    PubMed Central

    Sousa, Fernanda F.; Mendes, Simone M.; Santos-Amaya, Oscar F.; Araújo, Octávio G.; Oliveira, Eugenio E.

    2016-01-01

    Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50–70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations

  4. Investigating the Molecular Mechanisms of Organophosphate and Pyrethroid Resistance in the Fall Armyworm Spodoptera frugiperda

    PubMed Central

    Carvalho, Renato A.; Omoto, Celso; Field, Linda M.; Williamson, Martin S.; Bass, Chris

    2013-01-01

    The fall armyworm Spodoptera frugiperda is an economically important pest of small grain crops that occurs in all maize growing regions of the Americas. The intensive use of chemical pesticides for its control has led to the selection of resistant populations, however, to date, the molecular mechanisms underlying resistance have not been characterised. In this study the mechanisms involved in the resistance of two S. frugiperda strains collected in Brazil to chlorpyrifos (OP strain) or lambda-cyhalothrin (PYR strain) were investigated using molecular and genomic approaches. To examine the possible role of target-site insensitivity the genes encoding the organophosphate (acetylcholinesterase, AChE) and pyrethroid (voltage-gated sodium channel, VGSC) target-site proteins were PCR amplified. Sequencing of the S. frugiperda ace-1 gene identified several nucleotide changes in the OP strain when compared to a susceptible reference strain (SUS). These result in three amino acid substitutions, A201S, G227A and F290V, that have all been shown previously to confer organophosphate resistance in several other insect species. Sequencing of the gene encoding the VGSC in the PYR strain, identified mutations that result in three amino acid substitutions, T929I, L932F and L1014F, all of which have been shown previously to confer knockdown/super knockdown-type resistance in several arthropod species. To investigate the possible role of metabolic detoxification in the resistant phenotype of the OP and PYR stains all EST sequences available for S. frugiperda were used to design a gene-expression microarray. This was then used to compare gene expression in the resistant strains with the susceptible reference strain. Members of several gene families, previously implicated in metabolic resistance in other insects were found to be overexpressed in the resistant strains including glutathione S-transferases, cytochrome P450s and carboxylesterases. Taken together these results provide

  5. Xenon Feed System Progress

    DTIC Science & Technology

    2006-01-01

    From - To) 13-06-2006 Technical Paper 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER F04611-00-C-0055 Xenon Feed System Progress (Preprint) 5b. GRANT...propulsion xenon feed system for a flight technology demonstration program. Major accomplishments include: 1) Utilization of the Moog...successfully fed xenon to a 200 watt Hall Effect Thruster in a Technology Demonstration Program. The feed system has demonstrated throttling of xenon

  6. FEED FORWARD EQUATIONS.

    DTIC Science & Technology

    and feed forward stabilization) have been implemented. An on-mount gyro system consists of gyroscopes mounted on the radar antenna which sense...antenna motion and send compensating signals back to the antenna servo mechanism. Feed forward stabilization consists of determining antenna angular rates...caused by ships attitude changes, as measured by a stable platform (such as SINS), and feeding compensating signals back to the antenna servo

  7. Fiber Optic Feed

    DTIC Science & Technology

    1990-11-06

    Naval Research Laboratory IIK Washington, DC,20375 5000 NRL Memorandum Report 6741 0 N Fiber Optic Feed DENZIL STILWELL, MARK PARENT AND LEw GOLDBERG...SUBTITLE S. FUNDING NUMBERS Fiber Optic Feed 53-0611-A0 6. AUTHOR(S) P. D. Stilwell, M. G. Parent, L. Goldberg 7. PERFORMING ORGANIZATION NAME(S) AND...DISTRIBUTION CODE Approved for public release; distribution unlimited. 13. ABSTRACT (Maximum 200 words) This report details a Fiber Optic Feeding

  8. Mixed feed evaporator

    DOEpatents

    Vakil, Himanshu B.; Kosky, Philip G.

    1982-01-01

    In the preparation of the gaseous reactant feed to undergo a chemical reaction requiring the presence of steam, the efficiency of overall power utilization is improved by premixing the gaseous reactant feed with water and then heating to evaporate the water in the presence of the gaseous reactant feed, the heating fluid utilized being at a temperature below the boiling point of water at the pressure in the volume where the evaporation occurs.

  9. Characterization of volatiles of necrotic Stenocereus thurberi and Opuntia littoralis and toxicity and olfactory preference of Drosophila melanogster, D. mojavensis wrigleyi, and D. mojavensis sonorensis to necrotic cactus volatiles.

    PubMed

    Wright, Cynthia R; Setzer, William N

    2014-08-01

    Drosophila mojavensis wrigleyi and D. mojavensis sonorensis are geographically separated races of cactophilic fruit flies. D. mojavensis sonorensis inhabits the Sonoran Desert and utilizes necrotic rots of Stenocereus thurberi Engelm. as a food source and to oviposit while D. mojavensis wrigleyi inhabits Santa Catalina Island, California and utilizes the necrotic rots of Opuntia littoralis (Engelm.) Cockerell. The objectives of this study were to determine the volatile compositions of the necrotic cacti and to determine if the volatile components show either selective toxicity or attraction toward the fruit flies. The volatile chemical compositions of field-rot specimens of both necrotic cacti were obtained by dynamic headspace (purge-and-trap) and hydrodistillation techniques and analyzed by gas chromatography - mass spectrometry. The volatile fraction of necrotic S. thurberi early rot was dominated by carboxylic acids (84.8%) and the late rot by p-cresol (32.6% in the dynamic headspace sample and 55.9% in the hydrodistilled sample). O. littoralis volatiles were dominated by carboxylic acids (86% in the dynamic headspace sample and 89.1% in the hydrodistilled sample). Fifteen compounds that were identified in the necrotic rot volatiles were used to test insecticidal activity and olfactory preference on the cactophilic Drosophila species, as well as D. melanogaster. Differences in toxicity and olfactory preference were observed between the different taxa. Both races of D. mojavensis exhibited toxicity to benzaldehyde and 2-nonanone, while butanoic acid and palmitic acid were tolerated at high concentrations. D. m. wrigleyi demonstrated a greater olfactory preference for anisole, butanoic acid, 2-heptanone, and palmitic acid than did D. m. sonorensis, while D. m. sonorensis demonstrated a greater preference for hexadecane, octanoic acid, and oleic acid than did D. m. wrigleyi.

  10. VLBI2010 Feed Comparison

    NASA Technical Reports Server (NTRS)

    Petrachenko, Bill

    2013-01-01

    VLBI2010 requires a feed that simultaneously has high efficiency over the full 2.2-14 GHz frequency range. The simultaneity requirement implies that the feed must operate at high efficiency over the full frequency range without the need to adjust its focal position to account for frequency dependent phase centre variations. Two feeds meet this specification: The Eleven Feed developed at Chalmers University. (For more information, contact Miroslav Pantaleev, miroslav.pantaleev@chalmers.se. The Eleven Feed, integrated with LNA's in a cryogenic receiver, is available as a product from Omnisys Instruments, info@omnisys.se). The Quadruple Ridged Flared Horn (QRFH) developed at the California Institute of Technology. (For more information please contact Ahmed Akgiray, aakgiray@ieee.org or Sander Weinreb, sweinreb@caltech.edu) Although not VLBI2010 compliant, two triband S/X/Ka feeds are also being developed for the commissioning of VLBI2010 antennas, for S/X observations during the VLBI2010 transition period, and to support X/Ka CRF observations. The two feeds are: The Twin Telescopes Wettzell (TTW) triband feed developed by Mirad Microwave. (For more information please contact Gerhard Kronschnabl, Gerhard.Kronschnabl@bkg.bund.de) The RAEGE (Spain) triband feed developed at Yebes Observatory. (For more information please contact Jose Antonio Lopez Perez, ja.lopezperez@oan.es)

  11. Infectious waste feed system

    DOEpatents

    Coulthard, E. James

    1994-01-01

    An infectious waste feed system for comminuting infectious waste and feeding the comminuted waste to a combustor automatically without the need for human intervention. The system includes a receptacle for accepting waste materials. Preferably, the receptacle includes a first and second compartment and a means for sealing the first and second compartments from the atmosphere. A shredder is disposed to comminute waste materials accepted in the receptacle to a predetermined size. A trough is disposed to receive the comminuted waste materials from the shredder. A feeding means is disposed within the trough and is movable in a first and second direction for feeding the comminuted waste materials to a combustor.

  12. Feed up, Feedback, and Feed Forward

    ERIC Educational Resources Information Center

    Fisher, Douglas; Frey, Nancy

    2011-01-01

    "Feeding up" establishes a substantive line of inquiry that compels learners to engage in investigation and inquire. It also forms the basis for the assessments that follow. Once students understand the purpose and begin to work, they receive "feedback" that is timely and scaffolds their understanding. Based on their responses, the teacher gains a…

  13. Feed up, Feedback, and Feed Forward

    ERIC Educational Resources Information Center

    Fisher, Douglas; Frey, Nancy

    2011-01-01

    "Feeding up" establishes a substantive line of inquiry that compels learners to engage in investigation and inquire. It also forms the basis for the assessments that follow. Once students understand the purpose and begin to work, they receive "feedback" that is timely and scaffolds their understanding. Based on their responses, the teacher gains a…

  14. By-Product Feeds

    USDA-ARS?s Scientific Manuscript database

    By-product feeds are generated from the production of food, fiber, and bio-energy products for human consumption. They include plant feedstuffs such as hulls, stalks, peels, and oil seed meals, and animal by-products such as blood meal, fats, bone meal, or processed organ meats. Some feed by-product...

  15. Infant Feeding and Attachment.

    ERIC Educational Resources Information Center

    Ainsworth, Mary D. Salter; Tracy, Russel L.

    This paper has two major purposes: first, to consider how infant feeding behavior may fit into attachment theory; and second, to cite some evidence to show how an infant's early interaction with his mother in the feeding situation is related to subsequent development. It was found that sucking and rooting are precursor attachment behaviors that…

  16. Testing Feeds for Salmonella.

    USDA-ARS?s Scientific Manuscript database

    Human salmonellosis outbreaks have been linked to contamination of animal feeds. Thus it is crucial to employ sensitive Salmonella detection methods for animal feeds. Based on a review of the literature, Salmonella sustains acid injury at about pH 4.0 to5.0. Low pH can also alter the metabolism of S...

  17. Feeding biology of Cerambycids

    Treesearch

    Robert A. Haack

    2017-01-01

    There are more than 36,000 species of Cerambycidae recognized throughout the world (see Chapter 1), occurring on all continents except Antarctica (Linsley 1959). Given such numbers, it is not surprising that cerambycids display great diversity in their feeding habits. Both adults and larvae are almost exclusively phytophagous. Some adults appear not to feed at all,...

  18. Sensory suppression during feeding

    PubMed Central

    Foo, H.; Mason, Peggy

    2005-01-01

    Feeding is essential for survival, whereas withdrawal and escape reactions are fundamentally protective. These critical behaviors can compete for an animal's resources when an acutely painful stimulus affects the animal during feeding. One solution to the feeding-withdrawal conflict is to optimize feeding by suppressing pain. We examined whether rats continue to feed when challenged with a painful stimulus. During feeding, motor withdrawal responses to noxious paw heat either did not occur or were greatly delayed. To investigate the neural basis of sensory suppression accompanying feeding, we recorded from brainstem pain-modulatory neurons involved in the descending control of pain transmission. During feeding, pain-facilitatory ON cells were inhibited and pain-inhibitory OFF cells were excited. When a nonpainful somatosensory stimulus preactivated ON cells and preinhibited OFF cells, rats interrupted eating to react to painful stimuli. Inactivation of the brainstem region containing ON and OFF cells also blocked pain suppression during eating, demonstrating that brainstem pain-modulatory neurons suppress motor reactions to external stimulation during homeostatic behaviors. PMID:16275919

  19. Infant feeding: a review.

    PubMed

    Poskitt, E M

    1983-08-01

    Ideas on how infants should be fed have changed dramatically over the past ten years. This has led to some confusion, amongst both the public and those concerned with advising mothers, on safe and acceptable infant feeding practices. A contemporary view of infant feeding and its problems is presented.

  20. Development of Wideband Feed

    NASA Astrophysics Data System (ADS)

    Ujihara, Hideki; Takefuji, Kazuhiro; Sekido, Mamoru; Kondo, Tetsuro

    2015-08-01

    Wideband feeds have developed for Kashima 34m antenna and new 2.4m portable VLBI antennas. Prototypes of the wideband feeds are multimode horns, first one was set on 34m in the end of 2013, and then replaced next one with 6.5-15.0GHz receiving frequency. Now, a new feed for 3.2GHz-14.4GHz will be installed in 2.4m and 34m antennas in this spring, which are named NINJA feed, because of its design flexibility in beam shpae. Next, IGUANA feed is now under design and fabrication, which is aimed for 2.2-22GHz and covers VGOS(VLBI2010) specification. This has coaxial structure, the smaller "daughter feed" for 6.4-22GHz is placed in the center of the larger "Mother feed" for 2.2-6.4GHz.They are used for our project of time and frequency transfer between remote atomic clocks by wideband VLBI, named Gala-V(Garapagos VLBI), and will also be used wideband VLBI observation for astronmy and geodesy.Prototype feeds were tested in measurement of aperture efficiency, SEFD and Tsys of 34m "Super Kashima Antenna" and both 6.7/12.2GHz methanol maser detection in one reciever system, and then better one is used for wideband VLBI observations.

  1. Tube Feeding Transition Plateaus

    ERIC Educational Resources Information Center

    Klein, Marsha Dunn

    2007-01-01

    The journey children make from tube feeding to oral feeding is personal for each child and family. There is a sequence of predictable plateaus that children climb as they move toward orally eating. By better understanding this sequence, parents and children can maximize the development, learning, enjoyment and confidence at each plateau. The…

  2. Biocidal Compounds from Mentha sp. Essential Oils and Their Structure-Activity Relationships.

    PubMed

    Kimbaris, Athanasios C; González-Coloma, Azucena; Andrés, Maria Fe; Vidali, Veroniki P; Polissiou, Moschos G; Santana-Méridas, Omar

    2017-03-01

    Essential oils from Greek Mentha species showed different chemical compositions for two populations of M. pulegium, characterized by piperitone and pulegone. Mentha spicata essential oil was characterized by endocyclic piperitenone epoxide, piperitone epoxide, and carvone. The bioactivities of these essential oils and their components have been tested against insect pests (Leptinotarsa decemlineata, Spodoptera littoralis and Myzus persicae), root-knot nematodes (Meloydogine javanica) and plants (Lactuca sativa, Lolium perenne, Solanum lycopersicum). The structure-activity relationships of these compounds have been studied including semi-synthetic endocyclic trans-carvone epoxide, exocyclic carvone epoxide, a new exocyclic piperitenone epoxide and trans-pulegone epoxide. Leptinotarsa decemlineata feeding was affected by piperitenone and piperitone epoxide. Spodoptera littoralis was affected by piperitone epoxide and pulegone. The strongest nematicidal agent was piperitenone epoxide, followed by piperitone epoxide, piperitenone and carvone. Germination of S. lycopersicum and L. perenne was significantly affected by piperitenone epoxide. This compound and carvone epoxide inhibited L. perenne root and leaf growth. Piperitenone epoxide also inhibited the root growth of S. lycopersicum. The presence of a C(1) epoxide resulted in strong antifeedant, nematicidal and phytotoxic compounds regardless of the C(4) substituent. New natural crop protectants could be developed through appropriate structural modifications in the p-menthane skeleton. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  3. High Bacterial Agglutination Activity in a Single-CRD C-Type Lectin from Spodoptera exigua (Lepidoptera: Noctuidae)

    PubMed Central

    Gasmi, Leila; Ferré, Juan; Herrero, Salvador

    2017-01-01

    Lectins are carbohydrate-interacting proteins that play a pivotal role in multiple physiological and developmental aspects of all organisms. They can specifically interact with different bacterial and viral pathogens through carbohydrate-recognition domains (CRD). In addition, lectins are also of biotechnological interest because of their potential use as biosensors for capturing and identifying bacterial species. In this work, three C-type lectins from the Lepidoptera Spodoptera exigua were produced as recombinant proteins and their bacterial agglutination properties were characterized. The lowest protein concentration producing bacterial agglutination against a panel of different Gram+ and Gram− as well as their carbohydrate binding specificities was determined for the three lectins. One of these lectins, BLL2, was able to agglutinate cells from a broad range of bacterial species at an extremely low concentration, becoming a very interesting protein to be used as a biosensor or for other biotechnological applications involving bacterial capture. PMID:28257054

  4. Inga laurina trypsin inhibitor (ILTI) obstructs Spodoptera frugiperda trypsins expressed during adaptive mechanisms against plant protease inhibitors.

    PubMed

    Machado, Suzy Wider; de Oliveira, Caio Fernando Ramalho; Zério, Neide Graciano; Parra, José Roberto Postali; Macedo, Maria Lígia Rodrigues

    2017-08-01

    Plant protease inhibitors (PIs) are elements of a common plant defense mechanism induced in response to herbivores. The fall armyworm, Spodoptera frugiperda, a highly polyphagous lepidopteran pest, responds to various PIs in its diet by expressing genes encoding trypsins. This raises the question of whether the PI-induced trypsins are also inhibited by other PIs, which we posed as the hypothesis that Inga laurina trypsin inhibitor (ILTI) inhibits PI-induced trypsins in S. frugiperda. In the process of testing our hypothesis, we compared its properties with those of selected PIs, soybean Kunitz trypsin inhibitor (SKTI), Inga vera trypsin inhibitor (IVTI), Adenanthera pavonina trypsin inhibitor (ApTI), and Entada acaciifolia trypsin inhibitor (EATI). We report that ILTI is more effective in inhibiting the induced S. frugiperda trypsins than SKTI and the other PIs, which supports our hypothesis. ILTI may be more appropriate than SKTI for studies regarding adaptive mechanisms to dietary PIs. © 2017 Wiley Periodicals, Inc.

  5. Behavioral and biological responses ofCotesia marginiventris to kairomones of the fall armyworm,Spodoptera frugiperda.

    PubMed

    Loke, W H; Ashley, T R

    1984-03-01

    Potential kairomone sources of the fall armyworm (FAW),Spodoptera frugiperda (J.E. Smith), were bioassayed with females ofCotesia marginiventris (Cresson) in Petri dishes (10 cm diam). MatedC. marginiventris females, ranging in age from 1 to 3 days exhibited the most intense bioassay responses to potential sources of kairomone. Contacting a FAW-damaged corn leaf modified the pattern of movement inC. marginiventris from random to one exhibiting a significant increase in klinokinesis. No significant differences were present in kairomone responses of nonconditioned and conditioned parasitoids and parasitoid response to kairomones did not change throughout the photophase (0800-1800 hr). Removal of one, both, or the first eight antennal segments reduced or eliminated the response of the parasitoid to kairomones. Female parasitoids did not exhibit a preference for corn leaves damaged by a particular fall armyworm instar and parasitization rates were highest in larvae 48 hr old.

  6. Radar observations of the autumn migration of the beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) and other moths in northern China.

    PubMed

    Feng, H-Q; Wu, K-M; Cheng, D-F; Guo, Y-Y

    2003-04-01

    The autumn return migration of the beet armyworm Spodoptera exigua Hübner and other insects in northern China was observed with radar and with a simultaneously-operated searchlight trap and ground light-trap at a site in Langfang, near Beijing. The searchlight trap was found to be an efficient tool for trapping migrants and, operated alongside a ground light-trap, could distinguish migrant from locally-flying species. It was confirmed that S. exigua and some other species were high-altitude nocturnal windborne migrants during September and October in northern China. Maximum density of moths typically occurred below 500 m, and strong layering was often observed at about 200 m above ground level in airflows that would carry the moths towards the south. Descent of S. exigua in the vicinity of the radar site in late September was often associated with rain.

  7. "Click" reaction based synthesis of nimbolide derivatives and study of their insect antifeedant activity against Spodoptera litura Larvae.

    PubMed

    Siva, Bandi; Devi, Amujuri; Venkanna, Arramsetti; Poornima, Borra; Sukumar, Genji; Reddy, Solipeta Divya; Vijaya, Movva; Ummanni, Ramesh; Babu, Katragadda Suresh

    2017-09-06

    A series of Nimbolide-triazole conjugates were synthesized through copper(I)- catalyzed azide-alkyne "click" chemistry approach and these derivatives (2-4, 2a-2l) were characterized using modern spectroscopic techniques. Antifeedant activities of these derivatives were studied on Tobacco Caterpillar, Spodoptera litura (F.) using no-choice leaf disk bioassay. Interestingly, the synthesized derivatives were more effective in reducing feedancy by insect species when compared to the parent nimbolide. Among the tested compounds, 2a, 2c, and 2d showed potent antifeedancy with ED50 values of 0.49, 0.95 and 0.97mg/cm(2) against S. litura. Several of the analogs were also toxic or caused developmental abnormalities following leaf disc assay. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. High Bacterial Agglutination Activity in a Single-CRD C-Type Lectin from Spodoptera exigua (Lepidoptera: Noctuidae).

    PubMed

    Gasmi, Leila; Ferré, Juan; Herrero, Salvador

    2017-03-01

    Lectins are carbohydrate-interacting proteins that play a pivotal role in multiple physiological and developmental aspects of all organisms. They can specifically interact with different bacterial and viral pathogens through carbohydrate-recognition domains (CRD). In addition, lectins are also of biotechnological interest because of their potential use as biosensors for capturing and identifying bacterial species. In this work, three C-type lectins from the Lepidoptera Spodoptera exigua were produced as recombinant proteins and their bacterial agglutination properties were characterized. The lowest protein concentration producing bacterial agglutination against a panel of different Gram+ and Gram- as well as their carbohydrate binding specificities was determined for the three lectins. One of these lectins, BLL2, was able to agglutinate cells from a broad range of bacterial species at an extremely low concentration, becoming a very interesting protein to be used as a biosensor or for other biotechnological applications involving bacterial capture.

  9. Spodoptera frugiperda (J.E. Smith) with field-evolved resistance to Bt maize are susceptible to Bt pesticides.

    PubMed

    Jakka, S R K; Knight, V R; Jurat-Fuentes, J L

    2014-10-01

    Field-evolved resistance to maize event TC1507 expressing the Cry1Fa toxin from Bacillus thuringiensis (Bt) was detected in populations of Spodoptera frugiperda from Puerto Rico. We tested for cross-resistance to purified Cry1A toxins and commercial Bt pesticides in susceptible (Benzon) and TC1507-resistant (456) strains of S. frugiperda. Larvae from the 456 strain exhibited cross-resistance to Cry1Ab and Cry1Ac toxins, while no differences in susceptibility to XenTari WG and DiPel ES pesticides were detected. These data support cross-resistance to toxins that share binding sites with Cry1Fa and no cross-resistance to Bt pesticides in S. frugiperda with field-evolved resistance to Bt maize.

  10. Changes in midgut endopeptidase activity of Spodoptera frugiperda (Lepidoptera: Noctuidae) are responsible for adaptation to soybean proteinase inhibitors.

    PubMed

    Paulillo, L C; Lopes, A R; Cristofoletti, P T; Parra, J R; Terra, W R; Silva-Filho, M C

    2000-06-01

    The development of transgenic maize plants expressing soybean proteinase inhibitors could reduce the economic damage of one of the major maize pests in Brazil, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797). We examined the influence of soybean proteinase inhibitors on digestive enzyme properties and development of S. frugiperda larvae. The inhibition of trypsin and chymotrypsin activities in vitro by soybean proteinase inhibitors suggested that either Kunitz (SBTI) or Bowman-Birk (SBBI) would have a potential antimetabolic effect when ingested by insect larvae. However, chronic ingestion of semipurified soybean inhibitors did not result in a significant reduction of growth and development of fall armyworm. Therefore, digestive serine proteinase activities (trypsin and chymotrypsin) of fall armyworm larvae were characterized. The results suggest that S. frugiperda was able to physiologically adapt to dietary proteinase inhibitors by altering the complement of proteolytic enzymes in the insect midguts.

  11. Suthi feeding: an experience.

    PubMed

    Gupta, B D; Jain, P; Mandowara, S L

    1995-06-01

    In cases in which expressed breast milk is given or breast feeding cannot be done at all, a suitable alternative to breast feeding is still in question. Bottle feeding poses many hazards. Spoon and bowl have been proposed as a reasonable alternative since users can achieve better cleanliness. Yet it is impractical for staff in health facility nurseries to feed every newborn with the spoon and bowl method since it requires so much time. On average, they need to provide oral feeds to at least 10 babies a day. In India, maternal grandparents present the family of a newborn with the traditional Sindhi silver or stainless steel utensil to provide the infant drinking water. It is called Suthi. It holds either 10 or 20 cc, making it easier to quantify the amount of milk/feed. It has a long semicircular beak and curved rounded margins. Advantages of the Suthi over other alternative feeding methods include: it is a shallow container with a broad upper surface, allowing the user to clean it thoroughly and easily; its narrow beak can go directly into the mouth of the newborn, particularly premature infants and low birth weight infants, with relative ease, reducing the likelihood of spilling milk, and the Suthi feeding procedure is less messy and faster (7-10 vs. 15-20 minutes for spoon) than other procedures. The Suthi method allows nursery staff to spend less time per feed for 8-10 babies (minimum time needed, 1 vs. 3 hours). It can also be used at home. Its use will reduce the likelihood of aspiration since it cannot be used lying down. Since it is a traditional container, the community will accept Suthi. When breast feeding is not possible, the Suthi should be used.

  12. Challenges in measuring feed efficiency

    USDA-ARS?s Scientific Manuscript database

    The term feed efficiency is vague, and is defined differently by people. Historically, feed efficiency has been defined as the feed:gain (F:G) ratio or the inverse (G:F). Indexes have been developed to rank animals for feed efficiency. These indexes include residual feed intake (RFI) and residual...

  13. Baculovirus p35 gene is oppositely regulated by P53 and AP-1 like factors in Spodoptera frugiperda

    SciTech Connect

    Mohareer, Krishnaveni; Sahdev, Sudhir; Hasnain, Seyed E.

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Baculovirus p35 is regulated by both viral and host factors. Black-Right-Pointing-Pointer Baculovirus p35 is negatively regulated by SfP53-like factor. Black-Right-Pointing-Pointer Baculovirus p35 is positively regulated by SfAP-1-like factor. -- Abstract: Baculovirus p35 belongs to the early class of genes of AcMNPV and requires viral factors like Immediate Early protein-1 for its transcription. To investigate the role of host factors in regulating p35 gene expression, the putative transcription factor binding sites were examined in silico and the role of these factors in influencing the transcription of p35 gene was assessed. We focused our studies on AP-1 and P53-like factors, which are activated under oxidative stress conditions. The AP-1 motif is located at -1401 while P53 motif is at -1912 relative to p35 translation start site. The predicted AP-1 and P53 elements formed specific complexes with Spodoptera frugiperda nuclear extracts. Both AP-1 and P53 motif binding proteins were down regulated as a function of AcMNPV infection in Spodoptera cells. To address the question whether during an oxidative outburst, the p35 transcription is enhanced; we investigated the role of these oxidative stress induced host transcription factors in influencing p35 gene transcription. Reporter assays revealed that AP-1 element enhances the transcription of p35 by a factor of two. Interestingly, P53 element appears to repress the transcription of p35 gene.

  14. Phylogenetic Molecular Species Delimitations Unravel Potential New Species in the Pest Genus Spodoptera Guenée, 1852 (Lepidoptera, Noctuidae)

    PubMed Central

    Dumas, Pascaline; Barbut, Jérôme; Le Ru, Bruno; Silvain, Jean-François; Clamens, Anne-Laure; d’Alençon, Emmanuelle; Kergoat, Gael J.

    2015-01-01

    Nowadays molecular species delimitation methods promote the identification of species boundaries within complex taxonomic groups by adopting innovative species concepts and theories (e.g. branching patterns, coalescence). As some of them can efficiently deal with large single-locus datasets, they could speed up the process of species discovery compared to more time consuming molecular methods, and benefit from the existence of large public datasets; these methods can also particularly favour scientific research and actions dealing with threatened or economically important taxa. In this study we aim to investigate and clarify the status of economically important moths species belonging to the genus Spodoptera (Lepidoptera, Noctuidae), a complex group in which previous phylogenetic analyses and integrative approaches already suggested the possible occurrence of cryptic species and taxonomic ambiguities. In this work, the effectiveness of innovative (and faster) species delimitation approaches to infer putative species boundaries has been successfully tested in Spodoptera, by processing the most comprehensive dataset (in terms of number of species and specimens) ever achieved; results are congruent and reliable, irrespective of the set of parameters and phylogenetic models applied. Our analyses confirm the existence of three potential new species clusters (for S. exigua (Hübner, 1808), S. frugiperda (J.E. Smith, 1797) and S. mauritia (Boisduval, 1833)) and support the synonymy of S. marima (Schaus, 1904) with S. ornithogalli (Guenée, 1852). They also highlight the ambiguity of the status of S. cosmiodes (Walker, 1858) and S. descoinsi Lalanne-Cassou & Silvain, 1994. This case study highlights the interest of molecular species delimitation methods as valuable tools for species discovery and to emphasize taxonomic ambiguities. PMID:25853412

  15. Clearing obstructed feeding tubes.

    PubMed

    Marcuard, S P; Stegall, K L; Trogdon, S

    1989-01-01

    This is a report of an in vitro study evaluating the ability of six solutions to dissolve clotted enteral feeding, which can cause feeding tube occlusion. The following clotted enteral feeding products were tested: Ensure Plus, Ensure Plus with added protein (Promod 20 g/liter), Osmolite, Enrich, and Pulmocare. Clot dissolution was then tested by adding Adolf's Meat Tenderizer, Viokase, Sprite, Pepsi, Coke, or Mountain Dew. Distilled water served as control. Dissolution score for each mixture was assessed blindly. Best dissolution was observed with Viokase in pH 7.9 solution (p less than 0.01). Similar results were obtained when feeding tube patency was restored in eight in vitro occluded feeding tubes (Dobbhoff, French size 8) by using first Pepsi (two/eight successful) and then Viokase in pH 7.9 (six/six successful). We also report our experience in the first 10 patients with occluded feeding tubes using this Viokase solution injected through a Drum catheter into the feeding tube. In seven patients, this method proved to be successful, and the reasons for failure in three patients include a knotted tube, impacted tablet powder, and a formula clot fo 24 hr duration and 45 cm in length.

  16. Feeding regulation in Drosophila

    PubMed Central

    Pool, Allan-Hermann; Scott, Kristin

    2014-01-01

    Neuromodulators play a key role in adjusting animal behavior based on environmental cues and internal needs. Here, we review the regulation of Drosophila feeding behavior to illustrate how neuromodulators achieve behavioral plasticity. Recent studies have made rapid progress in determining molecular and cellular mechanisms that translate the metabolic needs of the fly into changes in neuroendocrine and neuromodulatory states. These neuromodulators in turn promote or inhibit discrete feeding behavioral subprograms. This review highlights the links between physiological needs, neuromodulatory states, and feeding decisions. PMID:24937262

  17. FRACTIONAL CRYSTALLIZATION FEED ENVELOPE

    SciTech Connect

    HERTING DL

    2008-03-19

    Laboratory work was completed on a set of evaporation tests designed to establish a feed envelope for the fractional crystallization process. The feed envelope defines chemical concentration limits within which the process can be operated successfully. All 38 runs in the half-factorial design matrix were completed successfully, based on the qualitative definition of success. There is no feed composition likely to be derived from saltcake dissolution that would cause the fractional crystallization process to not meet acceptable performance requirements. However, some compositions clearly would provide more successful operation than other compositions.

  18. Coal feed lock

    DOEpatents

    Pinkel, I. Irving

    1978-01-01

    A coal feed lock is provided for dispensing coal to a high pressure gas producer with nominal loss of high pressure gas. The coal feed lock comprises a rotor member with a diametral bore therethrough. A hydraulically activated piston is slidably mounted in the bore. With the feed lock in a charging position, coal is delivered to the bore and then the rotor member is rotated to a discharging position so as to communicate with the gas producer. The piston pushes the coal into the gas producer. The rotor member is then rotated to the charging position to receive the next load of coal.

  19. Sublethal Effects of Essential Oils From Eucalyptus staigeriana (Myrtales: Myrtaceae), Ocimum gratissimum (Lamiales: Laminaceae), and Foeniculum vulgare (Apiales: Apiaceae) on the Biology of Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Cruz, G S; Wanderley-Teixeira, V; Oliveira, J V; Lopes, F S C; Barbosa, D R S; Breda, M O; Dutra, K A; Guedes, C A; Navarro, D M A F; Teixeira, A A C

    2016-04-01

    Spodoptera frugiperda (Smith 1797) (Lepidoptera: Noctuidae) is a major pest of maize, Zea mays L. Its control is often achieved through repeated applications per season of insecticides, which may lead to adverse effects on the ecosystem. Thus, the study of alternative methods with less environmental impact has expanded to include the use of essential oils. These oils are products of the secondary metabolism in plants, and their insecticidal activity has been widely demonstrated in populations of many pest insects. This study evaluated the insecticidal activities of essential oils from Eucalyptus staigeriana, Ocimum gratissimum, and Foeniculum vulgare on Spodoptera frugiperda. Gas chromatography–mass spectrometry profiles and contact toxicity of these oils as well as their sublethal effects on larvae and reproductive parameters in adults were evaluated. All three oils had sublethal effects on S. frugiperda; however, the oil of O. gratissimum showed the best results at all doses tested. These essential oils may have promise for control of S. frugiperda.

  20. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000803.htm Breastfeeding vs. Formula Feeding To use the sharing features ... best for you and your family. Benefits of Breastfeeding Breastfeeding is a wonderful way to bond with ...

  1. Feeding Your Newborn

    MedlinePlus

    ... you choose to breastfeed or formula feed. About Breastfeeding Breastfeeding your newborn has many advantages. Perhaps most ... to care for her newborn. continue Limitations of Breastfeeding With all the good things known about breastfeeding, ...

  2. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... Habits for TV, Video Games, and the Internet Breastfeeding vs. Formula Feeding KidsHealth > For Parents > Breastfeeding vs. ... for you and your baby. continue All About Breastfeeding Nursing can be a wonderful experience for both ...

  3. Gastrostomy feeding tube - pump

    MedlinePlus

    ... before use. DO NOT add more formula or solid foods before you talk to your nurse. Feeding ... MD, gastroenterologist with Gastrointestinal Specialists of Georgia, Austell, GA. Review provided by VeriMed Healthcare Network. Also reviewed ...

  4. Feeding tube - infants

    MedlinePlus

    ... NG - infants Images Feeding tube References Kim YS. Nasogastric and nasoenteric tube insertion. In: Pfenninger JL, Fowler GC, eds. Pfenninger and Fowler's Procedures for Primary Care . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2011:chap ...

  5. On-Plant Larval Movement and Feeding Behavior of Fall Armyworm (Lepidoptera: Noctuidae) on Reproductive Corn Stages.

    PubMed

    Pannuti, L E R; Baldin, E L L; Hunt, T E; Paula-Moraes, S V

    2016-02-01

    Spodoptera frugiperda J.E. Smith (fall armyworm) is considered one of the most destructive pests of corn throughout the Americas. Although this pest has been extensively studied, little is known about its larval movement and feeding behavior on reproductive compared to vegetative corn stages. Thus, we conducted studies with two corn stages (R1 and R3) and four corn plant zones (tassel, above ear, ear zone, and below ear) in the field at Concord, NE (USA), and in the field and greenhouse at Botucatu, SP (Brazil), to investigate on-plant larval movement. The effects of different corn tissues (opened tassel, closed tassel, silk, kernel, and leaf), two feeding sequence scenarios (closed tassel-leaf-silk-kernel and leaf-silk-kernel), and artificial diet (positive control) on larval survival and development were also evaluated in the laboratory. Ear zone has a strong effect on feeding choice and survival of fall armyworm larvae regardless of reproductive corn stage. Feeding site choice is made by first-instar. Corn leaves of reproductive plants were not suitable for early instar development, but silk and kernel tissues had a positive effect on survival and development of fall armyworm larvae on reproductive stage corn. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Breast feeding in IMD.

    PubMed

    MacDonald, A; Depondt, E; Evans, S; Daly, A; Hendriksz, C; Chakrapani A, A; Saudubray, J-M

    2006-01-01

    Breast feeding has proven benefits for many infants with inherited metabolic disorders (IMDs) but, with the exception of phenylketonuria, there are few reports in other conditions. A questionnaire, completed by dietitians and clinicians from 27 IMD centres from 15 countries (caring for a total of over 8000 patients with IMDs on diet) identified breast feeding experience in IMD. Successful, demand breast feeding (in combination with an infant amino acid formula free of precursor amino acids) was reported in 17 infants with MSUD, 14 with tyrosinaemia type I, and 5 with homocystinuria. Eighty-nine per cent were still breast fed at 16 weeks. Fewer infants with organic acidaemias were demand breast fed (7 with propionic acidaemia; 6 with methylmalonic acidaemia and 13 with isovaleric acidaemia) (usually preceded by complementary feeds of a protein-free infant formula or infant amino acid formula free of precursor amino acids). Only 12 infants with urea cycle disorders were given demand breast feeds, but this was unsuccessful beyond 8 days in CPS deficiency. Further work is needed in developing guidelines for feeding and for clinical and biochemical monitoring for breast-fed infants with IMDs.

  7. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  8. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  9. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  10. Spatial patterns of aflatoxin levels in relation to ear-feeding insect damage in pre-harvest corn.

    PubMed

    Ni, Xinzhi; Wilson, Jeffrey P; Buntin, G David; Guo, Baozhu; Krakowsky, Matthew D; Lee, R Dewey; Cottrell, Ted E; Scully, Brian T; Huffaker, Alisa; Schmelz, Eric A

    2011-07-01

    Key impediments to increased corn yield and quality in the southeastern US coastal plain region are damage by ear-feeding insects and aflatoxin contamination caused by infection of Aspergillus flavus. Key ear-feeding insects are corn earworm, Helicoverpa zea, fall armyworm, Spodoptera frugiperda, maize weevil, Sitophilus zeamais, and brown stink bug, Euschistus servus. In 2006 and 2007, aflatoxin contamination and insect damage were sampled before harvest in three 0.4-hectare corn fields using a grid sampling method. The feeding damage by each of ear/kernel-feeding insects (i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs), and maize weevil population were assessed at each grid point with five ears. The spatial distribution pattern of aflatoxin contamination was also assessed using the corn samples collected at each sampling point. Aflatoxin level was correlated to the number of maize weevils and stink bug-discolored kernels, but not closely correlated to either husk coverage or corn earworm damage. Contour maps of the maize weevil populations, stink bug-damaged kernels, and aflatoxin levels exhibited an aggregated distribution pattern with a strong edge effect on all three parameters. The separation of silk- and cob-feeding insects from kernel-feeding insects, as well as chewing (i.e., the corn earworm and maize weevil) and piercing-sucking insects (i.e., the stink bugs) and their damage in relation to aflatoxin accumulation is economically important. Both theoretic and applied ramifications of this study were discussed by proposing a hypothesis on the underlying mechanisms of the aggregated distribution patterns and strong edge effect of insect damage and aflatoxin contamination, and by discussing possible management tactics for aflatoxin reduction by proper management of kernel-feeding insects. Future directions on basic and applied research related to aflatoxin contamination are also discussed.

  11. [Enteral tube feeding].

    PubMed

    Haller, Alois

    2014-03-01

    Tube feeding is an integral part of medical therapies, and can be easily managed also in the outpatient setting. Tube feeding by the stomach or small intestine with nasogastral or nasojejunal tubes is common in clinical practice. Long-term nutrition is usually provided through a permanent tube, i. e. a percutaneous endoscopic gastrostomy (PEG). Modern portable nutrition pumps are used to cover the patient's nutritional needs. Enteral nutrition is always indicated if patients can not or should not eat or if nutritional requirements cannot be covered within 3 days after an intervention, e. g. after abdominal surgery. Industrially produced tube feedings with defined substrate concentrations are being used; different compositions of nutrients, such as glutamine fish oil etc., are used dependent on the the condition of the patient. Enteral nutrition may be associated with complications of the tube, e. g. dislocation, malposition or obstruction, as well as the feeding itself, e. g.hyperglycaemia, electrolyte disturbances, refeeding syndrome diarrhea or aspiration). However, the benefit of tube feeding usually exceeds the potential harm substantially.

  12. Naturally Occurring Deletion Mutants Are Parasitic Genotypes in a Wild-Type Nucleopolyhedrovirus Population of Spodoptera exigua

    PubMed Central

    Muñoz, Delia; Castillejo, Juan I.; Caballero, Primitivo

    1998-01-01

    A wild-type nucleopolyhedrovirus (NPV) isolate from Spodoptera exigua from Florida (Se-US2) is a variant of the SeMNPV type strain since it has a unique DNA profile but is closely related to other known geographical isolates of SeMNPV. It consists of several genotypic variants, of which seven were identified in a Se-US2 virus stock by a modification of the in vivo cloning method developed by Smith and Crook (Virology 166:240–244, 1988). The US2A variant was the most prevalent genotype, and it was designated the prototype Se-US2 variant, while four of the variants (US2B, US2D, US2F, and US2H) were found at low frequency. US2C and US2E were also very abundant, and their diagnostic bands were easily observed in wild-type isolate restriction endonuclease patterns. The analysis of each variant, compared to the prototype US2A, showed that US2B and US2H presented minor differences, while US2D and US2F contained slightly larger insertions or deletions. Variants US2C and US2E contained major deletions of 21.1 and 14 kb, respectively, mapping at the same genomic region (between 14.5 and 30.2 map units [m.u.] and between 12.8 and 23 m.u., respectively). This is the first report of such deletion mutants in a natural baculovirus population. Variants US2A, US2B, US2D, US2F, and US2H were isolated as pure genotypes, but we failed to clone US2C and US2E in vivo. When these two variants appeared without apparent contamination with any other variant, they lost their pathogenicity for Spodoptera exigua larvae. A further biological characterization showed evidence that these two naturally occurring deletion mutants act as parasitic genotypes in the virus population. Bioassay data also demonstrated that pure US2A is significantly more pathogenic against second-instar S. exigua larvae than the wild-type isolate. The need for precise genotypic characterization of a baculovirus prior to its development as a bioinsecticide is discussed. PMID:9797293

  13. Commutating Feed Assembly.

    DTIC Science & Technology

    1979-12-01

    AD-AOBS 567 ITT GILFILLAN VAN NUYS CA F/6 17/9 CONF4UTATING FEED ASSEMBLY. 1W DEC 79 R WOL.FSON F19628-79-C-OOSS UNCLASSIFIED RADC -TR79303 NI. 1i.ll...INTRODUCTION 9 2 COMMUTATING FEED ASSEMBLY REQUIREMENTS 10 . 3 TECHNICAL PROBLEMS 11 1: 3.1 System Design 12 3.1.1 Radius of Circular Array 12 3.1.2 Design...Support Structure 16 3.3 Annular Rotary Coupler 16 3.4 Stripline Feed Network 17 w V.3.4.1 Range of Coupling Values vs. Percent Power into Load 17 3.4.2

  14. Cytokines and feeding.

    PubMed

    Plata-Salamán, C R

    2001-12-01

    Various categories of cytokines participate in the control of feeding, including interleukin-1 and -6 and other activators of gp 130, leptin (ob protein), interleukin-8 and other chemokines, tumor necrosis factor-alpha, and interferon-alpha. These feeding-inhibitory cytokines may play a role in the regulation of food intake during physiological (eg a role proposed for leptin) and pathophysiological (eg proinflammatory cytokines) conditions. Data show that various cytokines participate in acute and chronic disease-associated anorexia such as during infection, inflammation or malignancy. Food intake suppression (reported as anorexia) is also a common central manifestation observed during cytokine immunotherapy in humans. The concept of local production of various cytokines within specific brain regions in response to peripheral challenges and pathophysiological processes has broad implications for the interpretation of brain cytokines as mediators or participants in CNS modulation of feeding and anorexia.

  15. Infant-feeding Practices

    PubMed Central

    Oates, R. K.

    1973-01-01

    A survey of mothers attending infant welfare clinics showed that 26% changed their infant's milk in the first two weeks after birth and that multiple changes were common. Twenty-two per cent. were preparing a milk formula more concentrated than the recommended strength by using either heaped or packed scoops instead of level scoops of powder or by giving extra scoops. The commonest age for starting solid feeding was between 3 and 4 weeks and the practice of adding rusk or cereal to the bottle was common. There are obvious dangers of hypernatraemia from taking concentrated milk feeds and problems of obesity which may follow the early introduction of cereals. PMID:4740463

  16. High efficiency multifrequency feed

    NASA Technical Reports Server (NTRS)

    Ajioka, J. S.; Tsuda, G. I.; Leeper, W. A. (Inventor)

    1974-01-01

    Antenna systems and particularly compact and simple antenna feeds which can transmit and receive simultaneously in at least three frequency bands, each with high efficiency and polarization diversity are described. The feed system is applicable for frequency bands having nominal frequency bands with the ratio 1:4:6. By way of example, satellite communications telemetry bands operate in frequency bands 0.8 - 1.0 GHz, 3.7 - 4.2 GHz and 5.9 - 6.4 GHz. In addition, the antenna system of the invention has monopulse capability for reception with circular or diverse polarization at frequency band 1.

  17. Xanthophylls in Poultry Feeding

    NASA Astrophysics Data System (ADS)

    Breithaupt, Diemar R.

    Since most consumers associate an intense colour of food with healthy animals and high food quality, xanthophylls are widely used as feed additives to generate products that meet consumers' demands. An important large-scale application is in poultry farming, where xanthophylls are added to feed to give the golden colour of egg yolk that is so much appreciated. Now, with numerous new applications in human food, in the pharmaceutical industry, and in cosmetic products, there is an increasing demand for xanthophylls on the international market (Volume 5, Chapter 4).

  18. Specific response to herbivore-induced de novo synthesized plant volatiles provides reliable information for host plant selection in a moth.

    PubMed

    Zakir, Ali; Bengtsson, Marie; Sadek, Medhat M; Hansson, Bill S; Witzgall, Peter; Anderson, Peter

    2013-09-01

    Animals depend on reliable sensory information for accurate behavioural decisions. For herbivorous insects it is crucial to find host plants for feeding and reproduction, and these insects must be able to differentiate suitable from unsuitable plants. Volatiles are important cues for insect herbivores to assess host plant quality. It has previously been shown that female moths of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae), avoid oviposition on damaged cotton Gossypium hirsutum, which may mediated by herbivore-induced plant volatiles (HIPVs). Among the HIPVs, some volatiles are released following any type of damage while others are synthesized de novo and released by the plants only in response to herbivore damage. In behavioural experiments we here show that oviposition by S. littoralis on undamaged cotton plants was reduced by adding volatiles collected from plants with ongoing herbivory. Gas chromatography-electroantennographic detection (GC-EAD) recordings revealed that antennae of mated S. littoralis females responded to 18 compounds from a collection of headspace volatiles of damaged cotton plants. Among these compounds, a blend of the seven de novo synthesized volatile compounds was found to reduce oviposition in S. littoralis on undamaged plants under both laboratory and ambient (field) conditions in Egypt. Volatile compounds that are not produced de novo by the plants did not affect oviposition. Our results show that ovipositing females respond specifically to the de novo synthesized volatiles released from plants under herbivore attack. We suggest that these volatiles provide reliable cues for ovipositing females to detect plants that could provide reduced quality food for their offspring and an increased risk of competition and predation.

  19. Juvenile hormone analog technology: effects on larval cannibalism and the production of Spodoptera exigua (Lepidoptera: Noctuidae) nucleopolyhedrovirus.

    PubMed

    Elvira, Sonia; Williams, Trevor; Caballero, Primitivo

    2010-06-01

    The production of a multiple nucleopolyhedrovirus (SeMNPV) of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), has been markedly increased by using juvenile hormone analog (JHA) technology to generate a supernumerary sixth instar in the species. In the current study we compared the incidence of cannibalism in S. exigua fifth and sixth instars reared at low (two larvae per dish) and a high density (10 larvae per dish). The incidence of cannibalism was significantly higher in fifth instars compared with sixth instars and increased with rearing density on both instars. Infected larvae were more prone to become victims of cannibalism than healthy individuals in mixed groups comprising 50% healthy + 50% infected larvae in both instars reared at high density. Instar had a marked effect on occlusion body (OB) production because JHA-treated insects produced between 4.8- and 5.6-fold increase in OB production per dish compared with fifth instars at high and low densities, respectively. The insecticidal characteristics of OBs produced in JHA-treated insects, as indicated by LD50 values, were similar to those produced in untreated fourth or fifth instars. Because JHA technology did not increase the prevalence of cannibalism and had no adverse effect on the insecticidal properties of SeMNPV OBs, we conclude that the use of JHAs to generate a supernumerary instar is likely to be compatible with mass production systems that involve gregarious rearing of infected insects.

  20. Structural and biochemical characteristics of chitin-binding protein SeCBP66 from Spodoptera exigua (Hübner).

    PubMed

    Zhao, D; Liu, B; Zhang, Y K; Guo, W; Li, S Y; Lu, X J; Li, R J

    2016-08-12

    Peritrophic membrane proteins are important components of the insect peritrophic membrane. A novel cDNA gene encoding a chitin-binding protein, named secbp66, was identified by immunization screening of the cDNA library of Spodoptera exigua. The full length of secbp66 is 1806 bp, which encodes 602 amino acids. The predicted weight of the protein is 64.2 kDa. Bioinformatic analysis showed that a signal peptide composed of 17 amino acids located at the N-terminal of SeCBP66 contained seven tandem putative Type-II functional chitin-binding domains and five potential N-glycosylation sites, but no O-linked glycosylation sites. To study the properties of SeCBP66, recombinant SeCBP66 was successfully expressed in the insect cell line BTI-Tn-5B1-4 with a Bac-to-Bac expression system. A chitin binding experiment showed that the recombinant SeCBP66 protein could bind to chitin strongly. This study of the novel chitin-binding protein SeCBP66 provides a basis for developing new control targets for S. exigua.

  1. Field resistance of Spodoptera litura (Lepidoptera: Noctuidae) to organophosphates, pyrethroids, carbamates and four newer chemistry insecticides in Hunan, China.

    PubMed

    Tong, Hong; Su, Qi; Zhou, Xiaomao; Bai, Lianyang

    2013-01-01

    The present studies were carried out to evaluate resistance in the populations of Spodoptera litura Fab. (Lepidoptera, Noctuidae) from five districts of Hunan Province in China to various insecticides from 2010 to 2012 using a standard leaf dip bioassay method. For organophosphates and pyrethroids, resistance ratios compared with a susceptible Lab-BJ strain were in the range of 14-229-fold for organophosphates and 12-227-fold for pyrethroids. Similarly, relative low levels of resistance to emamectin, indoxacarb, and chlorfenapyr were observed in all five populations. In contrast, the resistance to carbamates (thiodicarb or methomyl) was significantly higher than that of organophosphates, pyrethroids and newer chemistry insecticides. The pairwise correlation coefficients of LC50 values indicated that the newer chemistry insecticides and old generation insecticides were not significant except abamectin, which was negatively significantly correlated with methomyl. A significant correlation was observed between thiodicarb, methomyl, and deltamethrin, whereas resistance to bifenthrin showed no correlations with resistance to other insecticides except deltamethrin. The results are discussed in relation to integrated pest management for S. litura with special reference to management of field evolved resistance to insecticides.

  2. Responses of the cutworm Spodoptera litura (Lepidoptera: Noctuidae) to two Bt corn hybrids expressing Cry1Ab.

    PubMed

    Yinghua, Shu; Yan, Du; Jin, Chen; Jiaxi, Wei; Jianwu, Wang

    2017-02-10

    To examine the responses of the secondary lepidopteran pest Spodoptera litura to two Bacillus thuringiensis (Bt) corn hybrids [5422Bt1 (Event Bt11), 5422CBCL (MON810)] expressing Cry1Ab, larval bioassays with Cry1Ab toxin, corn leaves or kernels and bagging on corn plants were conducted. The results showed that larvae displayed a similar performance when fed kernels, but not leaves of 5422Bt1, 5422CBCL and their near-isogenic non-Bt corn (5422). Significantly higher Cry1Ab amounts were detected in larvae fed leaves than kernels of both Bt hybrids, with different molecular weights of protein band in plants (72 and 90 kDa for 5422Bt1 and 5422CBCL, respectively), gut contents (65 kDa), feces (50 kDa), which indicated that larvae had lower ingestion, higher degradation and excretion of Cry1Ab when fed kernels not leaves of both Bt hybrids. Significantly higher levels of cadherin-like receptors and alkaline phosphatase transcripts were detected in larvae fed leaves than kernels of two Bt hybrids. Catalase, superoxide dismutase and glutathione-S-transferase activities in larvae fed 5422Bt1 leaves were significantly higher than that of 5422 treatments. Therefore, S. litura had low susceptibility to 5422Bt1 and 5422CBCL when larvae fed kernels not leaves of Bt corn. Additionally, S. litura presented a much stronger tolerance to 5422CBCL than 5422Bt1.

  3. Azadirachtin-induced apoptosis involves lysosomal membrane permeabilization and cathepsin L release in Spodoptera frugiperda Sf9 cells.

    PubMed

    Wang, Zheng; Cheng, Xingan; Meng, Qianqian; Wang, Peidan; Shu, Benshui; Hu, Qiongbo; Hu, Meiying; Zhong, Guohua

    2015-07-01

    Azadirachtin as a kind of botanical insecticide has been widely used in pest control. We previously reported that azadirachtin could induce apoptosis of Spodoptera litura cultured cell line Sl-1, which involves in the up-regulation of P53 protein. However, the detailed mechanism of azadirachtin-induced apoptosis is not clearly understood in insect cultured cells. The aim of the present study was to address the involvement of lysosome and lysosomal protease in azadirachtin-induced apoptosis in Sf9 cells. The result confirmed that azadirachtin indeed inhibited proliferation and induced apoptosis. The lysosomes were divided into different types as time-dependent manner, which suggested that changes of lysosomes were necessarily physiological processes in azadirachtin-induced apoptosis in Sf9 cells. Interestingly, we noticed that azadirachtin could trigger lysosomal membrane permeabilization and cathepsin L releasing to cytosol. Z-FF-FMK (a cathepsin L inhibitor), but not CA-074me (a cathepsin B inhibitor), could effectively hinder the apoptosis induced by azadirachtin in Sf9 cells. Meanwhile, the activity of caspase-3 could also be inactivated by the inhibition of cathepsin L enzymatic activity induced by Z-FF-FMK. Taken together, our findings suggest that azadirachtin could induce apoptosis in Sf9 cells in a lysosomal pathway, and cathepsin L plays a pro-apoptosis role in this process through releasing to cytosol and activating caspase-3. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Gene knockout demonstrates that vip3A contributes to the pathogenesis of Bacillus thuringiensis toward Agrotis ipsilon and Spodoptera exigua.

    PubMed

    Donovan, W P; Donovan, J C; Engleman, J T

    2001-07-01

    Vip3A is an 89-kDa protein secreted by Bacillus thuringiensis during vegetative growth. To determine the importance of Vip3A for the insect pathogenicity of B. thuringiensis the vip3A gene was deleted from strain HD1, yielding strain HD1Deltavip3A. Compared with HD1, strain HD1Deltavip3A was one-fourth as toxic to Agrotis ipsilon larvae and less than one-tenth as toxic to Spodoptera exigua larvae. When streptomycin was included in the S. exigua diet the toxicity of HD1Deltavip3A was approximately half that of HD1. Addition of HD1 spores increased the toxicity of purified Cry1 protein more than 600-fold against S. exigua, whereas addition of HD1Deltavip3A spores increased toxicity of Cry1 protein approximately 10-fold. These results demonstrate that an important component of B. thuringiensis insecticidal activity against S. exigua is the synthesis of Vip3A protein by B. thuringiensis cells after ingestion of spores and crystal proteins by insect larvae.

  5. Detection on emamectin benzoate-induced apoptosis and DNA damage in Spodoptera frugiperda Sf-9 cell line.

    PubMed

    Wu, Xiwei; Zhang, Lei; Yang, Chao; Zong, Mimi; Huang, Qingchun; Tao, Liming

    2016-01-01

    Emamectin benzoate (EMB), an important macrocyclic lactone insecticide that belongs to the avermectin family and possesses excellent potency in controlling pests, is non-carcinogenic and non-mutagenic conducted in rats and mice, but EMB-induced cytotoxicity and genotoxicity in arthropod insect have been seldom reported yet. In the present paper, we quantified the cytotoxicity of EMB through the detections on cell viability, DNA damage, and cell apoptosis in Spodoptera frugiperda Sf-9 cells in vitro. The results showed that EMB caused a concentration- and time-dependent reduction on the viability of Sf-9 cells, and the median inhibitory concentrations (IC50) were 3.34μM at 72h of exposure. The dual acridine orange/ethidium bromide staining showed that exposure to EMB induced a significant time- and concentration-dependent increase on cell apoptosis. The alkaline comet assay revealed that EMB induced significant increases on single-strand DNA breaks, and the percentage of γH2AX-positive cells represented a time- and concentration-dependent formation of DNA double-strand breaks in Sf-9 cells. Interestingly, the similar cytotoxic actions of EMB also went for the human cancerous HeLa cells as a control cell group. Data demonstrated the potential cytotoxic effect of EMB on Sf-9 cells that was significantly greater than the effect of hydrogen peroxide at the same concentrations. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Cross-resistance, mode of inheritance and stability of resistance to emamectin in Spodoptera litura (Lepidoptera: Noctuidae).

    PubMed

    Shad, Sarfraz Ali; Sayyed, Ali H; Saleem, Mushtaq A

    2010-08-01

    Spodoptera litura (F.) is a cosmopolitan pest that has developed resistance to several insecticides. The aim of the present study was to establish whether an emamectin-selected (Ema-SEL) population could render cross-resistance to other insecticides, and to investigate the genetics of resistance. Bioassays at G(1) gave resistance ratios (RRs) of 80-, 2980-, 3050- and 2800-fold for emamectin, abamectin, indoxacarb and acetamiprid, respectively, compared with a laboratory susceptible population Lab-PK. After three rounds of selection, resistance to emamectin in Ema-SEL increased significantly, with RRs of 730-fold and 13-fold compared with the Lab-PK and unselected (UNSEL) population respectively. Further studies revealed that three generations were required for a tenfold increase in resistance to emamectin. Resistance to abamectin, indoxacarb, acetamiprid and emamectin in UNSEL declined significantly compared with the field population at G(1). Furthermore, selection with emamectin reduced resistance to abamectin, indoxacarb and acetamiprid on a par with UNSEL. Crosses between Ema-SEL and Lab-PK indicated autosomal and incomplete dominance of resistance. A direct test of a monogenic model and Land's method suggested that resistance to emamectin was controlled by more than one locus. Instability of resistance and lack of cross-resistance to other insecticides suggest that insecticides with different modes of action should be recommended to reduce emamectin selection pressure. Copyright (c) 2010 Society of Chemical Industry.

  7. Transgenics in groundnut (Arachis hypogaea L.) expressing cry1AcF gene for resistance to Spodoptera litura (F.).

    PubMed

    Keshavareddy, G; Rohini, S; Ramu, S V; Sundaresha, S; Kumar, A R V; Kumar, P Ananda; Udayakumar, M

    2013-07-01

    Large number of primary transgenic events were generated in groundnut by an Agrobacterium mediated, in planta transformation method to assess the efficacy of cry1AcF against the Spodoptera litura. The amplification of required size fragment of 750 bp with npt II primers and 901 bp with cry1AcF gene primers confirmed the integration of the gene. The expression of the cry gene was ascertained by ELISA in T2 generation, and the maximum concentration of cry protein in transgenic plants reached approximately 0.82 μg/g FW. Further, Southern blot analysis of ten T2 transgenic plants proved that transgene had been integrated in the genome of all the plants and Northern analysis of the same plants demonstrated the active expression of cry1AcF gene. The highest mean % larval mortalities 80.0 and 85.0 with an average mean % larval mortalities 16.25 (n = 369) and 26.0 (n = 80) were recorded in T1 and T2 generations, respectively. Segregation analysis of the selected lines in the T3 generation demonstrated homozygous nature. This clearly proved that though there is considerable improvement in average mean % larval mortality in T2 generation, the cry1AcF gene was effective against S. litura only to some extent.

  8. Assessment of electron beam-induced abnormal development and DNA damage in Spodoptera litura (F.) (Lepidoptera: Noctuidae)

    NASA Astrophysics Data System (ADS)

    Yun, Seung-Hwan; Lee, Seon-Woo; Koo, Hyun-Na; Kim, Gil-Hah

    2014-03-01

    The armyworm, Spodoptera litura (F.) is a polyphagous and important agricultural pest worldwide. In this study, we examined the effect of electron beam irradiation on developmental stages, reproduction, and DNA damage of S. litura. Eggs (0-24 h old), larvae (3rd instar), pupae (3 days old after pupation), and adults (24 h after emergence) were irradiated with electron beam irradiation of six levels between 30 and 250 Gy. When eggs were irradiated with 100 Gy, egg hatching was completely inhibited. When the larvae were irradiated, the larval period was significantly delayed, depending on the doses applied. At 150 Gy, the fecundity of adults that developed from irradiated pupae was entirely inhibited. However, electron beam irradiation did not induce the instantaneous death of S. litura adults. Reciprocal crosses between irradiated and unirradiated moths demonstrated that females were more radiosensitive than males. We also conducted the comet assay immediately after irradiation and over the following 5 days period. Severe DNA fragmentation in S. litura cells was observed just after irradiation and the damage was repaired during the post-irradiation period in a time-dependent manner. However, at more than 100 Gy, DNA damage was not fully recovered.

  9. Recombinant destabilase-lysozyme: synthesis de novo in E. coli and action mechanism of the enzyme expressed in Spodoptera frugiperda.

    PubMed

    Zavalova, L L; Baskova, I P; Barsova, E V; Snezhkov, E V; Akopov, S B; Lopatin, S A

    2004-07-01

    Destabilase-lysozyme (DL) from salivary gland secretion of the medicinal leech (Hirudo medicinalis) is as a member of the invertebrate lysozyme family, which sharply differs from other lysozyme families. In this study, DL lysozyme function was confirmed during expression of a gene encoding DL in Escherichia coli. Several constructs of the expression vectors pKK OmpA and pET-3A with or without bacterial, leech, or yeast signal peptides (SP) were used. The use of a construct without signal peptide genes resulted in normal growth of the transformed cells. Transformation of E. coli cells with the constructs containing SP was accompanied by the disruption of the forming cells. The use of the expression vector pET-32 LTC-System for production of DL as a fusion protein with thioredoxin also resulted in normal cell growth. However, specific activity of DL isolated from such cells was significantly lower than that of enzyme purified from extracts of Spodoptera frugiperda cells, which were infected with the baculovirus vector carrying DL cDNA. It is shown that the action mechanism of invertebrate lysozyme does not differ from that of other families: recombinant DL from S. frugiperda extracts catalyzed cleavage of synthetic substrate, hexamer of N-acetylglucosamine, to di- and tetramers, which is typical for enzymatic function of other lysozyme families.

  10. Responses of the cutworm Spodoptera litura (Lepidoptera: Noctuidae) to two Bt corn hybrids expressing Cry1Ab

    PubMed Central

    Yinghua, Shu; Yan, Du; Jin, Chen; Jiaxi, Wei; Jianwu, Wang

    2017-01-01

    To examine the responses of the secondary lepidopteran pest Spodoptera litura to two Bacillus thuringiensis (Bt) corn hybrids [5422Bt1 (Event Bt11), 5422CBCL (MON810)] expressing Cry1Ab, larval bioassays with Cry1Ab toxin, corn leaves or kernels and bagging on corn plants were conducted. The results showed that larvae displayed a similar performance when fed kernels, but not leaves of 5422Bt1, 5422CBCL and their near-isogenic non-Bt corn (5422). Significantly higher Cry1Ab amounts were detected in larvae fed leaves than kernels of both Bt hybrids, with different molecular weights of protein band in plants (72 and 90 kDa for 5422Bt1 and 5422CBCL, respectively), gut contents (65 kDa), feces (50 kDa), which indicated that larvae had lower ingestion, higher degradation and excretion of Cry1Ab when fed kernels not leaves of both Bt hybrids. Significantly higher levels of cadherin-like receptors and alkaline phosphatase transcripts were detected in larvae fed leaves than kernels of two Bt hybrids. Catalase, superoxide dismutase and glutathione-S-transferase activities in larvae fed 5422Bt1 leaves were significantly higher than that of 5422 treatments. Therefore, S. litura had low susceptibility to 5422Bt1 and 5422CBCL when larvae fed kernels not leaves of Bt corn. Additionally, S. litura presented a much stronger tolerance to 5422CBCL than 5422Bt1. PMID:28186125

  11. The Mechanism by Which Dodecyl Dimethyl Benzyl Ammonium Chloride Increased the Toxicity of Chlorpyrifos to Spodoptera exigua

    PubMed Central

    Cui, Li; Yuan, Huizhu; Yang, Daibin; Rui, Changhui; Mu, Wei

    2017-01-01

    Beet armyworm, Spodoptera exigua (Hübner) is one of the most destructive pests that causes significant losses in crops. Unfortunately, S. exigua have developed resistance toward the majority of insecticides. Synergists may provide an important choice to deal with the resistance problems. Dodecyl dimethyl benzyl ammonium chloride (DDBAC) is a cationic surfactant, which displayed enhancement effect when combined with chlorpyrifos against S. exigua, giving enhancement factors of 1.50 and 1.57 at the concentrations of 90 and 810 mg L−1. In order to clarify the possible mechanisms, we investigate the effects of DDBAC on detoxification enzymes. However, DDBAC showed no inhibition on these enzymes activities. Meanwhile, scanning electron microscope images indicated DDBAC did not affect the cuticle super micro structure of S. exigua. The alterations in cuticular penetration rate have also been observed; indeed, it has been suggested that synergism is obtained by an acceleration of insecticide penetration through the cuticle. The chlorpyrifos penetration increased sharply when combined with 90 and 810 mg L−1 DDBAC, with only 12.6 and 8.5% of the initial chlorpyrifos recovered by external rinsing after 8 h. In contrast, when there was no DDBAC, more than 23.3% of the initial dose was recovered after 8 h. PMID:28769805

  12. Cytomegalovirus immediate-early promoter efficiently drives heterogeneous gene expression in Spodoptera frugiperda (Sf9) insect cells.

    PubMed

    Li, S; Zhang, Q N; Zhang, X T; Zheng, X Y; Lv, Y F; Hao, Z M

    2014-03-05

    Recently, wide attention has been given to the potential of recombinant baculovirus as a gene transfer vehicle for mammalian gene therapy. In this study, we packaged the recombinant baculoviruses with cytomegalovirus immediate-early (CMV-IE) promoter in Spodoptera frugiperda (Sf9) insect cells, and found that the CMV-IE promoter could efficiently drive the exogenic gene expression in the cells 12 h post-infection (h.p.i.). The expression level at 72 h.p.i. was only around half of that driven by polyhedrin promoter (Ppolh). However, the biological activity of the reporter proteins at 72 h.p.i. were similar with that driven by Ppolh. In addition, the Sf9 cells transfected with CMV-IE-containing plasmids also expressed foreign genes, suggesting that the CMV-IE-directed heterogeneous gene expression in the Sf9 cells was baculovirus-independent. These results demonstrate that the CMV-IE promoter might be used as a regular promoter in Sf9 cells.

  13. Spinosad induces programmed cell death involves mitochondrial dysfunction and cytochrome C release in Spodoptera frugiperda Sf9 cells.

    PubMed

    Yang, Mingjun; Wang, Bo; Gao, Jufang; Zhang, Yang; Xu, Wenping; Tao, Liming

    2017-02-01

    Spinosad, a reduced-risk insecticide, acts on the nicotinic acetylcholine receptors and the gamma-aminobutyric acid receptor in the nervous system of target insects. However, its mechanism of action in non-neural insect cells is unclear. This study aimed to evaluate mitochondrial functional changes associated with spinosad in Spodoptera frugiperda (Sf9) insect cells. Our results indicate that in Sf9 cells, spinosad induces programmed cell death and mitochondrial dysfunction through enhanced reactive oxygen species production, mitochondrial permeability transition pore (mPTP) opening, and mitochondrial membrane potential collapse, eventually leading to cytochrome C release and apoptosis. The cytochrome C release induced by spinosad treatment was partly inhibited by the mPTP inhibitors cyclosporin A and bongkrekic acid. Subsequently, we found that spinosad downregulated Bcl-2 expression and upregulated p53 and Bax expressions, activated caspase-9 and caspase-3, and triggered PARP cleavage in Sf9 cells. These findings suggested that spinosad-induced programmed cell death was modulated by mitochondrial dysfunction and cytochrome C release.

  14. Dominance of Cry1F resistance in Spodoptera frugiperda (Lepidoptera: Noctuidae) on TC1507 Bt maize in Brazil.

    PubMed

    Farias, Juliano R; Andow, David A; Horikoshi, Renato J; Sorgatto, Rodrigo J; dos Santos, Antonio C; Omoto, Celso

    2016-05-01

    Dominance of resistance has been one of the major parameters affecting the rate of evolution of resistance to Bt crops. High dose is the capacity of Bt crops to kill heterozygous insects and has been an essential component of the most successful strategy to manage resistance to these crops. Experiments were conducted to evaluate directly and indirectly whether the TC1507 event is high dose to Spodoptera frugiperda (JE Smith). About 8% of heterozygote neonate larvae were able to survive, complete larval development and emerge as normal adults on TC1507 leaves, while susceptible larvae could not survive for 5 days. The estimated dominance of resistance was 0.15 ± 0.09 and significantly higher than zero; therefore, the resistance to Cry1F expressed in TC1507 was not completely recessive. A 25-fold dilution of TC1507 maize leaf tissue in an artificial diet was able to cause a maximum mortality of only 37%, with growth inhibition of 82% at 7 days after larval infestation. Resistance to Cry1F in TC1507 maize is incompletely recessive in S. frugiperda. TC1507 maize is not high dose for S. frugiperda. Additional or alternative resistance management strategies, such as the replacement of single-trait Bt maize with pyramided Bt maize, which produces multiple proteins targeting the same insect pests, should be implemented wherever this technology is in use and S. frugiperda is the major pest. © 2015 Society of Chemical Industry.

  15. Nerium oleander indirect leaf photosynthesis and light harvesting reductions after clipping injury or Spodoptera eridania herbivory: high sensitivity to injury.

    PubMed

    Delaney, Kevin J

    2012-04-01

    Variable indirect photosynthetic rate (P(n)) responses occur on injured leaves after insect herbivory. It is important to understand factors that influence indirect P(n) reductions after injury. The current study examines the relationship between gas exchange and chlorophyll a fluorescence parameters with injury intensity (% single leaf tissue removal) from clipping or Spodoptera eridania Stoll (Noctuidae) herbivory on Nerium oleander L. (Apocynaceae). Two experiments showed intercellular [CO(2)] increases but P(n) and stomatal conductance reductions with increasing injury intensity, suggesting non-stomatal P(n) limitation. Also, P(n) recovery was incomplete at 3d post-injury. This is the first report of a negative exponential P(n) impairment function with leaf injury intensity to suggest high N. oleander leaf sensitivity to indirect P(n) impairment. Negative linear functions occurred between most other gas exchange and chlorophyll a fluorescence parameters with injury intensity. The degree of light harvesting impairment increased with injury intensity via lower (1) photochemical efficiency indicated lower energy transfer efficiency from reaction centers to PSII, (2) photochemical quenching indicated reaction center closure, and (3) electron transport rates indicated less energy traveling through PSII. Future studies can examine additional mechanisms (mesophyll conductance, carbon fixation, and cardenolide induction) to cause N. oleander indirect leaf P(n) reductions after injury. Published by Elsevier Ireland Ltd.

  16. Antimicrobial activity of conditioned medium fractions from Spodoptera frugiperda Sf9 and Trichoplusia ni Hi5 insect cells.

    PubMed

    Svensson, Ingrid; Calles, Karin; Lindskog, Eva; Henriksson, Hongbin; Eriksson, Ulrika; Häggström, Lena

    2005-11-01

    Concentrated conditioned medium (CM) fractions from Spodoptera frugiperda Sf9 and Trichoplusia ni cells, eluting from a gel filtration column at around 10 kDa, were found to exhibit strong antibacterial activity against Bacillus megaterium and Escherichia coli. The B. megaterium cells incubated in the CM fraction from Sf9 cells rapidly lost viability: after 8 min the viability had decreased to 0.7%, as compared with the control. Addition of the CM fraction to E. coli cells resulted in a less drastic drop in viability: 65% viability was lost after 60 min of incubation. Further, exposure to the CM fraction caused a substantial leakage of intracellular proteins, as demonstrated by SDS-PAGE analysis. Cell lysis was confirmed by optical density measurements, microscopic investigations and flow cytometry. B. megaterium exposed to a CM fraction from T. ni cells lost 97% of their viability in about 40 min. Ubiquitin, thioredoxin and cyclophilin were identified in the antibacterial fraction from Sf9 cells by mass spectrometry and N-terminal amino acid sequencing. Other proteins in the fraction gave no matches in a database search. Since ubiquitin was shown not to cause the antimicrobial effect and thioredoxin and cyclophilin were likely not involved, the responsible agent may be an unknown protein, not yet registered in databases. The antimicrobial effect of the CM fraction from T. ni cells most probably comes from a lysozyme precursor protein.

  17. Purification and characterization of biliverdin-binding vitellogenin from the hemolymph of the common cutworm, Spodoptera litura.

    PubMed

    Maruta, Kousei; Yoshiga, Toyoshi; Katagiri, Chihiro; Ochiai, Masanori; Tojo, Sumio

    2002-06-01

    Biliverdin-binding vitellogenin (Vg) was purified from adult female hemolymph of the common cutworm, Spodoptera litura, by using gel filtration and ion exchange chromatographies. The molecular mass of the protein was 490 kDa and it was composed of two 188-kDa subunits. Three internal amino acid sequences obtained by digestion of the protein with lysylendopeptidase showed high similarity to those of Bombyx mori Vg, supporting the purified blue protein to be vitellogenin. latroscan analyses demonstrated the presence of biliverdin in Vg that occupied 2.4% of total lipid components. Among the lipids of Vg (9.5 micrograms total lipids per 100 micrograms protein), diacylglycerol was the most predominant, followed by phospholipid, hydrocarbons, and then triacylglycerol, while in biliverdin-binding proteins (BPs) purified from larval hemolymph (3.1 micrograms total lipids per 100 micrograms protein), phospholipid was the most abundant lipid followed by diacylglycerol; hydrocarbons and triacylglycerol were minor components. Vg was first detected in the hemolymph of female pupae one day before eclosion, but injection of 5 micrograms of methoprene into a 3-day-old pupa induced Vg in the hemolymph 4 days earlier than in the control. Methoprene also induced a faster decline in BP-A and BP-B titers in the hemolymph with a corresponding increase of the Vg titer. These results suggest that juvenile hormone (JH) induces not only vitellogenesis but also the uptake of these proteins by stimulating the metamorphosis of fat body during the pupal stage.

  18. Recombinant Cry1Ia protein is highly toxic to cotton boll weevil (Anthonomus grandis Boheman) and fall armyworm (Spodoptera frugiperda).

    PubMed

    Martins, E S; Aguiar, R W D S; Martins, N F; Melatti, V M; Falcão, R; Gomes, A C M M; Ribeiro, B M; Monnerat, R G

    2008-05-01

    To evaluate the activity of cry1Ia gene against cotton pests, Spodoptera frugiperda and Anthonomus grandis. Had isolated and characterized a toxin gene from the Bacillus thuringiensis S1451 strain which have been previously shown to be toxic to S. frugiperda and A. grandis. The toxin gene (cry1Ia) was amplified by PCR, sequenced, and cloned into the genome of a baculovirus. The Cry1Ia protein was expressed in baculovirus infected insect cells, producing protein inclusions in infected cells. The Cry1Ia protein has used in bioassays against to S. frugiperda and A. grandis. Bioassays using the purified recombinant protein showed high toxicity to S. frugiperda and A. grandis larvae. Molecular modelling of the Cry1Ia protein translated from the DNA sequence obtained in this work, showed that this protein possibly posses a similar structure to the Cry3A protein. Ultrastructural analysis of midgut cells from A. grandis incubated with the Cry1Ia toxin, showed loss of microvilli integrity. The results indicate that the cry1Ia is a good candidate for the construction of transgenic plants resistant to these important cotton pests.

  19. Aminopeptidase N1 is involved in Bacillus thuringiensis Cry1Ac toxicity in the beet armyworm, Spodoptera exigua

    PubMed Central

    Qiu, Lin; Cui, Songhe; Liu, Lang; Zhang, Boyao; Ma, Weihua; Wang, Xiaoping; Lei, Chaoliang; Chen, Lizhen

    2017-01-01

    Understanding how insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) interact with their hosts is crucial to fully explain the molecular bases of Bt specificity and insecticidal activity. Previous studies support ATP binding cassette transporters (ABCC2/3) and one cadherin-like protein are Cry1Ac functional receptors in the beet armyworm (Spodoptera exigua). In this study, a combined one-dimensional gel electrophoresis and immunoblotting approach identified aminopeptidase N (APNs) as putative Cry1Ac binding proteins in the midgut brush border membrane of S. exigua larvae. Functional analyses by gene silencing of six different S. exigua APN genes (SeAPN1, SeAPN2, SeAPN3, SeAPN4, SeAPN5 and SeAPN6) showed that only suppression of SeAPN1 resulted in decreased larval susceptibility to Cry1Ac toxin. These results support that SeAPN1 plays important functional role in Cry1Ac toxicity in S. exigua. PMID:28327568

  20. Time-shifted reproductive behaviours among fall armyworm (Noctuidae: Spodoptera frugiperda) host strains: evidence for differing modes of inheritance.

    PubMed

    Schöfl, Gerhard; Heckel, D G; Groot, A T

    2009-07-01

    The noctuid moth Spodoptera frugiperda consists of two strains associated with different larval host plants (most notably corn and rice). These strains exhibit differential temporal patterns of female calling and copulation during scotophase, with the corn strain more active earlier in the night. We investigated strain-specific constraints in reproductive timing, mating interactions between the two strains, and the mode of inheritance of timing of female calling, male calling, copulation and oviposition. We observed an allochronic shift of all reproductive behaviours by approximately 3 h and a parallel shift of nonreproductive locomotor activity, suggesting involvement of the circadian clock. The corn strain was more variable in the timing of calling and copulation than the rice strain. Rice strain females were more restricted in the timing of copulation than rice strain males, while such differences between the sexes were not apparent in the corn strain. There were significant interactions between the strains affecting onset times of copulation and male calling. The four investigated reproductive traits differed in their modes of inheritance: timing of female and male calling exhibited strong maternal effects, timing of copulation was controlled by a combination of maternal effects and corn strain dominant autosomal factors, and timing of oviposition was inherited in a corn strain dominant fashion. We conclude that the allochronic separation of reproduction between fall armyworm strains is asymmetric, less pronounced than previously thought, and under complex genetic control.

  1. Resistance to dual-gene Bt maize in Spodoptera frugiperda: selection, inheritance, and cross-resistance to other transgenic events

    PubMed Central

    Santos-Amaya, Oscar F.; Rodrigues, João V. C.; Souza, Thadeu C.; Tavares, Clébson S.; Campos, Silverio O.; Guedes, Raul N.C.; Pereira, Eliseu J.G.

    2015-01-01

    Transgenic crop “pyramids” producing two or more Bacillus thuringiensis (Bt) toxins active against the same pest are used to delay evolution of resistance in insect pest populations. Laboratory and greenhouse experiments were performed with fall armyworm, Spodoptera frugiperda, to characterize resistance to Bt maize producing Cry1A.105 and Cry2Ab and test some assumptions of the “pyramid” resistance management strategy. Selection of a field-derived strain of S. frugiperda already resistant to Cry1F maize with Cry1A.105 + Cry2Ab maize for ten generations produced resistance that allowed the larvae to colonize and complete the life cycle on these Bt maize plants. Greenhouse experiments revealed that the resistance was completely recessive (Dx = 0), incomplete, autosomal, and without maternal effects or cross-resistance to the Vip3Aa20 toxin produced in other Bt maize events. This profile of resistance supports some of the assumptions of the pyramid strategy for resistance management. However, laboratory experiments with purified Bt toxin and plant leaf tissue showed that resistance to Cry1A.105 + Cry2Ab2 maize further increased resistance to Cry1Fa, which indicates that populations of fall armyworm have high potential for developing resistance to some currently available pyramided maize used against this pest, especially where resistance to Cry1Fa was reported in the field. PMID:26675246

  2. Type-A allatostatins from the fall armyworm, Spodoptera frugiperda: molecular cloning, expression and tissue-specific localization.

    PubMed

    Abdel-Latief, Mohatmed; Meyering-Vos, Martina; Hoffmann, Klaus H

    2004-07-01

    The gene encoding the Spodoptera frugiperda allatostatin type-A peptide family (Y/FXFGL-amides) was isolated from S. frugiperda brain cDNA. The gene encodes a precursor of 231 amino acids containing nine (or ten) Y/FXFGL-a peptides that are tandemly arranged in three blocks. The comparison of the Spofr-AST A precursor with the respective precursor genes from two other lepidopteran species, Helicoverpa armigera and Bombyx mori, shows high homology in size, sequence (84 and 57%, respectively), and organisation of the allatostatins. One-step RT-PCR analysis using a Spofr-AST A-6 to A-9 probe shows that the gene is not only expressed as one transcript in the brain and midgut of larvae and adults in a time- and tissue-specific manner, but also in the reproductive tissues of adult S. frugiperda. Data confirm the nature of the allatostatin type-A peptides as brain/gut myoregulatory hormones, whereas their function(s) in ovaries, oviduct, and testes still have to be resolved. The cell-specific localization of the preprohormone expression, as demonstrated by whole mount in situ hybridization, confirms the overall distribution of the Spofr-AST A preprohormone as shown by RT-PCR and supports the pleiotropic functions of the peptides. Copyright 2004 Wiley-Liss, Inc.

  3. Frequency of Cry1F Non-Recessive Resistance Alleles in North Carolina Field Populations of Spodoptera frugiperda (Lepidoptera: Noctuidae)

    PubMed Central

    Li, Guoping; Reisig, Dominic; Miao, Jin; Gould, Fred; Huang, Fangneng; Feng, Hongqiang

    2016-01-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a target species of transgenic corn (Zea mays L.) that expresses single and pyramided Bacillus thuringiensis (Bt) toxin. In 2014, S. frugiperda were collected from a light trap in North Carolina, and a total of 212 F1/F2 isofemale lines of S. frugiperda were screened for resistance to Bt and non-Bt corn. All of the 212 isolines were susceptible to corn tissue expressing Cry1A.105 + Cry2Ab, Cry1F + Cry1A.105 + Cry2Ab, and Cry1F + Cry1Ab + Vip3Aa20. Growth rate bioassays were performed to isolate non-recessive Bt resistance alleles. Seven individuals out of the 212 isofemale lines carried major non-recessive alleles conferring resistance to Cry1F. A pooled colony was created from the seven individuals. This colony was 151.21 times more resistant to Cry1F than a known-susceptible population and was also resistant to Cry1A.105, but was not resistant to Cry2Ab and Vip3Aa20. The results demonstrate that field populations of S. frugiperda collected from North Carolina are generally susceptible to Cry1F, but that some individuals carry resistant alleles. The data generated in this study can be used as baseline data for resistance monitoring. PMID:27119741

  4. Mechanism and DNA-based detection of field-evolved resistance to transgenic Bt corn in fall armyworm (Spodoptera frugiperda).

    PubMed

    Banerjee, Rahul; Hasler, James; Meagher, Robert; Nagoshi, Rodney; Hietala, Lucas; Huang, Fangneng; Narva, Kenneth; Jurat-Fuentes, Juan Luis

    2017-09-07

    Evolution of resistance threatens sustainability of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). The fall armyworm (Spodoptera frugiperda) is a devastating pest of corn in the Western Hemisphere initially controlled by transgenic Bt corn producing the Cry1Fa insecticidal protein (event TC1507). However field-evolved resistance to TC1507 was observed in Puerto Rico in 2007 and has subsequently been reported in a number of locations in North and South America. Early studies on Puerto Rico fall armyworm populations found that the resistance phenotype was associated with reduced expression of alkaline phosphatase. However, in this work we show that field-evolved resistance to Cry1Fa Bt corn in Puerto Rico is closely linked to a mutation in an ATP Binding Cassette subfamily C2 (ABCC2) gene that functions as a Cry1Fa receptor in susceptible insects. Furthermore, we report a DNA-based genotyping test used to demonstrate the presence of the resistant (SfABCC2mut) allele in Puerto Rico populations in 2007, coincident with the first reports of damage to TC1507 corn. These DNA-based field screening data provide strong evidence that resistance to TC1507 in fall armyworm maps to the SfABCC2 gene and provides a useful molecular marker for detecting the SfABCC2mut allele in resistant fall armyworm.

  5. [Morphology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae (Lepidoptera: Noctuidae) fed on neem-treated leaves].

    PubMed

    Correia, Alicely A; Wanderley-Teixeira, Valéria; Teixeira, Alvaro A C; Oliveira, José V de; Torres, Jorge B

    2009-01-01

    Research involving plants with insecticide activity evolved significantly in the last decades. Among these plants, the neem tree, Azadirachta indica, is commonly used against several insects, mainly Lepidoptera. The neem efficiency depends on the target insect and on the concentration used. A barrier against potential toxic agents ingested together with the food is the alimentary canal. Thus, this research aimed to describe the histology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae fed on leaves treated with neem (Neemseto) at a concentration of 0.5% and 1.0% and non treated, at different intervals (48, 96, 144, 192 and 240 h), by quantifying the regenerative cells and analyzing the secretion of the mesenteron histochemically. Larvae were immobilized at low temperatures (-4 degrees C), the alimentary canal was removed, fixed in Boüin s aqueous, embedded in paraplast and historesin, sectioned and stained with hematoxilin-eosin and periodic acid- Schiff. The histology of the alimentary canal of S. frugiperda was similar to other lepidopterans. Neem effects on morphology were seen only in the mesenteron, depending on the time and concentration used, such as: epithelium, reduction on regenerative cells and on the secretory activity in this region, confirmed by the histochemistry in both neem concentrations. These alterations were observed after 96 h at 1.0%, and 144 h at 0.5%. These results indicate that neem (Neemseto), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron.

  6. Induction of Autophagy and Apoptosis via PI3K/AKT/TOR Pathways by Azadirachtin A in Spodoptera litura Cells

    PubMed Central

    Shao, Xuehua; Lai, Duo; Zhang, Ling; Xu, Hanhong

    2016-01-01

    Azadirachtin is one of the most effective botanical insecticides and has been widely used in pest control. Toxicological reports show that azadirachtin can induce apoptosis in various insect cell lines. However, studies of azadirachtin-induced autophagy in cultured insect cells are lacking. This study reports that azadirachtin A significantly inhibits cell proliferation by inducing autophagic and apoptotic cell death in Spodoptera litura cultured cell line (SL-1 cell). Characteristic autophagolysosome and Atg8-PE (phosphatidylethanolamine) accumulation were observed by electron microscopy and western blotting, indicating that azadirachtin triggered autophagy in SL-1 cell. Furthermore, azadirachtin inhibited survival signaling by blocking the activation of PI3K, AKT and the down-stream target of rapamycin. Similar to the positive control of starvation, azadirachtin induced the activation of insulin receptor (InR) via a cellular feedback mechanism. In addition, the autophagy-related 5 (Atg5), a molecular switch of autophagy and apoptosis, was truncated (tAtg5) to trigger cytochrome c release into the cytoplasm under azadirachtin stress, which indicated that azadirachtin induced apoptosis through autophagy. Our findings suggest that azadirachtin primarily induced autophagy in SL-1 cell by dysregulating InR- and PI3K/AKT/TOR pathways, then stimulated apoptosis by activating tAtg5. PMID:27752103

  7. Jejunostomy feeding tube

    MedlinePlus

    Feeding - jejunostomy tube; G-J tube; J-tube; Jejunum tube ... Q-tip to clean the skin around the J-tube 1 to 3 times a day with ... To flush the J-tube, follow the instructions your nurse gave you. You will use the syringe to slowly push warm water into ...

  8. Feed Your Brain!

    ERIC Educational Resources Information Center

    Failmezger, Tammie L.

    2006-01-01

    Language arts teachers and library media specialists bear the responsibility of teaching students how to properly feed their brains. In this article, the author describes how she teaches her students to make wise choices when selecting books. Furthermore, she presents the "Brain Food Pyramid" model that looks similar to the food pyramid but it…

  9. Infant feeding and vision

    USDA-ARS?s Scientific Manuscript database

    Over the past several years, a number of randomized controlled trials have compared the effects of breastfeeding and formula feeding and the effects of docosahexaenoic acid (DHA)–supplemented and non-supplemented formulas on visual function in both preterm and term infants. Some studies have shown b...

  10. Feeding of Diarmis Proboscis

    ERIC Educational Resources Information Center

    Young, Jocelyn

    2005-01-01

    The feeding of Diarmis proboscis is an exciting outdoor laboratory activity that demonstrates a single concept of adaptations--cryptic colorations. The students are "transformed" into D. proboscis (no Harry Potter magic needed) in order to learn how adaptations work in the natural world. Prior to beginning this activity, students should have a…

  11. 2011 Feds Feed Families

    NASA Image and Video Library

    2011-07-01

    NASA employees Anita Douglas (l to r), Amy Grose, Aaron Brooks and Cabrina Bell sort through early contributions to the 2011 Feds Feed Families Food Drive at Stennis Space Center. Each summer for three years, federal agencies across the nation have worked together to collect nonperishable food for local food banks across the country.

  12. Feeding DDGS to Finfish

    USDA-ARS?s Scientific Manuscript database

    Globally, aquaculture has been growing at a rapid pace (currently 8.5% per year) over the past two decades, and is recognized as the fastest growing food production sector of agriculture in the U.S. Growth of aquaculture and other industries (e.g., other monogastric and ruminant livestock feed appl...

  13. Dust feed mechanism

    DOEpatents

    Milliman, Edward M.

    1984-01-01

    The invention is a dust feed device for delivery of a uniform supply of dust for long periods of time to an aerosolizing means for production of a dust suspension. The device utilizes at least two tandem containers having spiral brushes within the containers which transport the dust from a supply to the aerosolizer means.

  14. Feed Your Brain!

    ERIC Educational Resources Information Center

    Failmezger, Tammie L.

    2006-01-01

    Language arts teachers and library media specialists bear the responsibility of teaching students how to properly feed their brains. In this article, the author describes how she teaches her students to make wise choices when selecting books. Furthermore, she presents the "Brain Food Pyramid" model that looks similar to the food pyramid but it…

  15. Feeding of Diarmis Proboscis

    ERIC Educational Resources Information Center

    Young, Jocelyn

    2005-01-01

    The feeding of Diarmis proboscis is an exciting outdoor laboratory activity that demonstrates a single concept of adaptations--cryptic colorations. The students are "transformed" into D. proboscis (no Harry Potter magic needed) in order to learn how adaptations work in the natural world. Prior to beginning this activity, students should have a…

  16. ASDC RSS Feeds

    Atmospheric Science Data Center

    2013-03-08

    ... Features ASDC's RSS feed with highlights about Earth Science Data at NASA Langley Research Center ASDC Scheduled ... one of them to see what's new. When you sign up, you receive breaking news on your computer as soon as it is released. How can ...

  17. [History of complementary feeding].

    PubMed

    Turck, D

    2010-12-01

    Complementary feeding, which embraces all solid and liquid foods other than breast milk or infant formula, is strongly influenced by cultural, familial and economic factors. For many times, there was a strong taboo on the use of colostrum ("the white blood") during the first week after delivery, sometimes even the first month. Therefore, the newborn baby received complementary foods as gruel, or panada. However, in the Greek civilization, wet nurses were asked by contract to breastfeed exclusively for the first 6 months and to start complementary feeding thereafter. From the sixteenth century onwards, many writers deplored the practice of giving gruel and panada during the first six months before the teeth erupted. In 1921, a Swedish pediatrician, Jundell, reported for the first time that starting complementary feeding at 6 months of age was associated with a better growth and resistance to infections. The recommendation of the World Health Organization to start complementary feeding after a 6-month period of exclusive breastfeeding is often in contradiction with the habits of the populations to propose very early other food sources than breast milk. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  18. Effect of feed presentation on feeding patterns of dairy calves.

    PubMed

    Miller-Cushon, E K; Bergeron, R; Leslie, K E; Mason, G J; DeVries, T J

    2013-01-01

    The objectives of this study were to determine the effect of feed presentation on meal frequency and duration, as well as diurnal feeding patterns of dairy calves, and to assess any longer-term differences in feeding patterns resulting from previous experience. Twenty Holstein bull calves were exposed from wk 1 to 8 of life to 1 of 2 feed presentation treatments: concentrate and chopped grass hay (<2.5 cm) offered at a ratio of 7:3 as a mixture (MIX), or as separate components (COM). Feed was provided ad libitum. Calves received 8L/d of milk replacer (1.2 kg of dry matter), with the amount progressively reduced after 5 wk to facilitate weaning by the end of wk 7. At the beginning of wk 9, all calves received the MIX diet and remained on trial for an additional 3 wk. Feeding behavior was recorded from video for 4d during wk 6, 8, 9, and 11. In wk 6, calves fed MIX spent more time feeding than calves fed COM (56.7 vs. 46.8 min/d). In wk 8, calves fed MIX spent more time feeding (174.0 vs. 139.1 min/d) and had a lower rate of intake (11.5 vs. 14.7 g/min) compared with calves fed COM. Meal frequency was similar between treatments (12.2 meals/d). Diurnal feeding patterns in wk 8 were also affected by feed presentation, with calves fed MIX spending less time feeding at time of feed delivery and more time feeding throughout the rest of the daylight hours than calves fed COM. Diurnal feeding patterns of hay and concentrate in wk 8 differed for calves fed COM, with more time spent consuming hay at time of feed delivery and less time spent consuming hay throughout the rest of the day. Once calves previously fed COM were transitioned to the MIX diet in wk 9, meal frequency, meal duration, and diurnal feeding patterns were similar between treatments: both treatments spent similar amounts of time feeding (173.9 min/d) and had similar peaks in feeding activity at time of feed delivery, sunrise, and sunset. Provision of hay and concentrate to young calves as a mixed ration

  19. Feeding rate as valuable information in primate feeding ecology.

    PubMed

    Nakagawa, Naofumi

    2009-04-01

    In this review I outline studies on wild non-human primates using information on feeding rate, which is defined as the food intake per minute on a dry-weight basis; further, I summarize the significance of feeding rate in primate feeding ecology. The optimal foraging theory has addressed three aspects of animal feeding: (1) optimal food patch choice, (2) optimal time allocation to different patches, and (3) optimal food choice. In order to gain a better understanding of these three aspects, the feeding rate itself or its relevance indices (e.g., rates of calorie and protein intake) could be appropriate measures to assess the quality of food and food patches. Moreover, the feeding rate plays an essential role in estimation of total food intake, because it varies greatly for different food items and the feeding time is not a precise measure. The feeding rate could also vary across individuals who simultaneously feed on the same food items in the same food patch. Body size-dependent and rank-dependent differences in the feeding rate sometimes cause individuals to take strategic behavioral options. In the closing remarks, I discuss the usefulness of even limited data on feeding rate obtained under adverse observational conditions in understanding primate feeding ecology.

  20. Prospects of complete feed system in ruminant feeding: A review

    PubMed Central

    Beigh, Yasir Afzal; Ganai, Abdul Majeed; Ahmad, Haidar Ali

    2017-01-01

    Effective utilization of available feed resources is the key for economical livestock rearing. Complete feed system is one of the latest developments to exploit the potential of animal feed resources in the best possible way. The complete feed is a quantitative mixture of all dietary ingredients, blended thoroughly to prevent separation and selection, fed as a sole source of nutrients except water and is formulated in a desired proportion to meet the specific nutrient requirements. The concentrate and roughage levels may vary according to the nutrient requirement of ruminants for different production purposes. The complete feed with the use of fibrous crop residue is a noble way to increase the voluntary feed intake and thus animal’s production performance. In this system of feeding, the ruminant animals have continuous free choice availability of uniform feed mixture, resulting in more uniform load on the rumen and less fluctuation in release of ammonia which supports more efficient utilization of ruminal non-protein nitrogen. Feeding complete diet stabilizes ruminal fermentation, thereby improves nutrient utilization. This feeding system allows expanded use of agro-industrial by­products, crop residues and nonconventional feeds in ruminant ration for maximizing production and minimizing feeding cost, thus being increasingly appreciated. However, to extend the concept extensively to the field and make this technology successful and viable for farmers, more efforts are needed to be taken. PMID:28507415

  1. Islam and infant feeding.

    PubMed

    Shaikh, Ulfat; Ahmed, Omar

    2006-01-01

    Few physicians in the United States receive formal education related to principles of infant care in Islamic families. Breastfeeding has a religious basis in Islam and it is recommended that the mother suckle her offspring for 2 years if possible. Weaning from the breast before that period is allowed if mutually decided on by both parents. The infant's father has an obligation to support his wife through any circumstances that may affect breastfeeding and, in case of divorce, provide shelter and financial support to the mother-infant dyad for as long as breastfeeding continues. By showing understanding and respect of Islamic beliefs related to infant feeding, clinicians can help support healthy early feeding of Muslim infants.

  2. Representing infant feeding: content analysis of British media portrayals of bottle feeding and breast feeding

    PubMed Central

    Henderson, Lesley; Kitzinger, Jenny; Green, Josephine

    2000-01-01

    Objective To examine how breast feeding and bottle feeding are represented by the British media. Design Content analysis. Subjects Television programmes and newspaper articles that made reference to infant feeding during March 1999. Setting UK mass media. Main outcome measures Visual and verbal references to breast or bottle feeding in newspapers and television programmes. Results Overall, 235 references to infant feeding were identified in the television sample and 38 in the newspaper sample. Bottle feeding was shown more often than breast feeding and was presented as less problematic. Bottle feeding was associated with “ordinary” families whereas breast feeding was associated with middle class or celebrity women. The health risks of formula milk and the health benefits of breast feeding were rarely mentioned. Conclusions The media rarely present positive information on breast feeding, even though this feeding practice is associated with the most health benefits. Health professionals and policy makers should be aware of patterns in media coverage and the cultural background within which women make decisions about infant feeding. PMID:11073512

  3. First Report of Outbreaks of the Fall Armyworm Spodoptera frugiperda (J E Smith) (Lepidoptera, Noctuidae), a New Alien Invasive Pest in West and Central Africa.

    PubMed

    Goergen, Georg; Kumar, P Lava; Sankung, Sagnia B; Togola, Abou; Tamò, Manuele

    2016-01-01

    The fall armyworm Spodoptera frugiperda is a prime noctuid pest of maize on the American continents where it has remained confined despite occasional interceptions by European quarantine services in recent years. The pest has currently become a new invasive species in West and Central Africa where outbreaks were recorded for the first time in early 2016. The presence of at least two distinct haplotypes within samples collected on maize in Nigeria and São Tomé suggests multiple introductions into the African continent. Implications of this new threat to the maize crop in tropical Africa are briefly discussed.

  4. First Report of Outbreaks of the Fall Armyworm Spodoptera frugiperda (J E Smith) (Lepidoptera, Noctuidae), a New Alien Invasive Pest in West and Central Africa

    PubMed Central

    Sankung, Sagnia B.; Togola, Abou; Tamò, Manuele

    2016-01-01

    The fall armyworm Spodoptera frugiperda is a prime noctuid pest of maize on the American continents where it has remained confined despite occasional interceptions by European quarantine services in recent years. The pest has currently become a new invasive species in West and Central Africa where outbreaks were recorded for the first time in early 2016. The presence of at least two distinct haplotypes within samples collected on maize in Nigeria and São Tomé suggests multiple introductions into the African continent. Implications of this new threat to the maize crop in tropical Africa are briefly discussed. PMID:27788251

  5. Overview of FEED, the Feeding Experiments End-user Database

    PubMed Central

    Wall, Christine E.; Vinyard, Christopher J.; Williams, Susan H.; Gapeyev, Vladimir; Liu, Xianhua; Lapp, Hilmar; German, Rebecca Z.

    2011-01-01

    The Feeding Experiments End-user Database (FEED) is a research tool developed by the Mammalian Feeding Working Group at the National Evolutionary Synthesis Center that permits synthetic, evolutionary analyses of the physiology of mammalian feeding. The tasks of the Working Group are to compile physiologic data sets into a uniform digital format stored at a central source, develop a standardized terminology for describing and organizing the data, and carry out a set of novel analyses using FEED. FEED contains raw physiologic data linked to extensive metadata. It serves as an archive for a large number of existing data sets and a repository for future data sets. The metadata are stored as text and images that describe experimental protocols, research subjects, and anatomical information. The metadata incorporate controlled vocabularies to allow consistent use of the terms used to describe and organize the physiologic data. The planned analyses address long-standing questions concerning the phylogenetic distribution of phenotypes involving muscle anatomy and feeding physiology among mammals, the presence and nature of motor pattern conservation in the mammalian feeding muscles, and the extent to which suckling constrains the evolution of feeding behavior in adult mammals. We expect FEED to be a growing digital archive that will facilitate new research into understanding the evolution of feeding anatomy. PMID:21700574

  6. Overview of FEED, the feeding experiments end-user database.

    PubMed

    Wall, Christine E; Vinyard, Christopher J; Williams, Susan H; Gapeyev, Vladimir; Liu, Xianhua; Lapp, Hilmar; German, Rebecca Z

    2011-08-01

    The Feeding Experiments End-user Database (FEED) is a research tool developed by the Mammalian Feeding Working Group at the National Evolutionary Synthesis Center that permits synthetic, evolutionary analyses of the physiology of mammalian feeding. The tasks of the Working Group are to compile physiologic data sets into a uniform digital format stored at a central source, develop a standardized terminology for describing and organizing the data, and carry out a set of novel analyses using FEED. FEED contains raw physiologic data linked to extensive metadata. It serves as an archive for a large number of existing data sets and a repository for future data sets. The metadata are stored as text and images that describe experimental protocols, research subjects, and anatomical information. The metadata incorporate controlled vocabularies to allow consistent use of the terms used to describe and organize the physiologic data. The planned analyses address long-standing questions concerning the phylogenetic distribution of phenotypes involving muscle anatomy and feeding physiology among mammals, the presence and nature of motor pattern conservation in the mammalian feeding muscles, and the extent to which suckling constrains the evolution of feeding behavior in adult mammals. We expect FEED to be a growing digital archive that will facilitate new research into understanding the evolution of feeding anatomy.

  7. Nutritional content of modular feeds: how accurate is feed production?

    PubMed

    Evans, Sharon; Daly, Anne; Ashmore, Catherine; Gokmen-Ozel, Hulya; Dileva, Rosemary; Dumbleton, Belinda; Chahal, Satnam; Macdonald, Anita

    2013-03-01

    This prospective, observational study examined the accuracy of modular feed preparation for children with complex medical conditions requiring specialist feeds. Participants who regularly prepare special feeds at home were observed preparing two feeds with equivalent nutrient composition: a 2-ingredient (2-IF) and 6-ingredient feed (6-IF) under research-conditions, and 8 weeks later under home-conditions. The same feeds (2-IF and 6-IF) prepared by a trained feed-maker served as controls. Biochemical analysis of nutrient content was performed as an objective measure of feed preparation accuracy. 52 participants were studied: one patient and 51 caregivers. Biochemical nutrient analysis was inaccurate for both feeds including control-feeds but was better for the 2-IF. Both feeds were lower in fat than the expected calculation but more so in the 6-IF than the 2-IF (median: 34% vs 84% of calculated research-condition values and 66% vs 90% home-conditions; p<0.0001). Conversely zinc was higher in the 6-IF than the 2-IF (median: 127% vs 87% research-conditions and 130% vs 89% home-conditions; p<0.0001). Preparation errors included: incorrect use of equipment, poor recipe adherence and ingredient measurement mistakes. Even in control-feeds there was equipment inaccuracy, poor ingredient emulsification and ingredient residue left in mixing/measuring containers. Fewer errors occurred with powdered than liquid ingredients. Many errors associated with special feed production are difficult to control. Carers of children with complex medical conditions require improved preparation equipment and techniques and the development of premeasured or combined ingredient preparations to maximise feed accuracy and minimise clinical risk.

  8. Three heat shock proteins from Spodoptera exigua: Gene cloning, characterization and comparative stress response during heat and cold shocks.

    PubMed

    Xu, Qi; Zou, Qi; Zheng, Huizhen; Zhang, Fan; Tang, Bin; Wang, Shigui

    2011-06-01

    To gain insight into the comparative function in stress response of HSPs in insects, three HSP cDNAs were cloned from the fat body of the beet armyworm Spodoptera exigua (Lepidoptera, Noctuidae). SexHSP70, SexHSP74 and SexHSP83 cDNAs encoding the protein of 667, 685 and 717 amino acids, with the pI of 5.52, 5.75 and 5.02, respectively. Northern blotting revealed that all three SexHSP mRNAs are expressed in the fat body, mid-gut, spermary and tracheae. SexHSP70, SexHSP74and SexHSP83 mRNAs were expressed in the fat body and whole body at different levels during different developmental stages. The three SexHSP transcripts were highly expressed in the fat body on the first day of fifth instar larvae, on the fourth and seventh days of the pupa stage, and in the whole body on the initial stages of larvae. Under heat and cold shock conditions, SexHSP70 and SexHSP83 mainly functioned during heat shock and cooling and SexHSP83 also had a function in the recovery stage. SexHSP74 had important functions in short-term heat shock and recovery, as well as long-term cooling. The results revealed that long-term shocking can affect SexHSP74 and SexHSP83 expression and long-term cooling can influence SexHSP83 expression during the recovery stage.

  9. Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculovirus.

    PubMed

    Crava, Cristina M; Jakubowska, Agata K; Escriche, Baltasar; Herrero, Salvador; Bel, Yolanda

    2015-01-01

    Antimicrobial peptides (AMPs) and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae), a polyphagous pest that is commonly controlled by products based on Bacillus thuringiensis (Bt) or baculovirus. First, we comprehensively characterized the transcripts encoding AMPs and lysozymes expressed in S. exigua larval midgut, identifying 35 transcripts that represent the S. exigua arsenal against microbial infection. Secondly, we analyzed their expression in the midgut after ingestion of sub-lethal doses of two different pore-forming B. thuringiensis toxins, Cry1Ca and Vip3Aa, and the S. exigua nucleopolyhedrovirus (SeMNPV). We observed that both Bt toxins triggered a similar, wide and in some cases high transcriptional activation of genes encoding AMPs and lysozymes, which was not reflected in the activation of the classical systemic immune-marker phenoloxidase in hemolymph. Baculovirus ingestion resulted in the opposed reaction: Almost all transcripts coding for AMPs and lysozymes were down-regulated or not induced 96 hours post infection. Our results shed light on midgut response to different virulence factors or pathogens used nowadays as microbial control agents and point out the importance of the midgut immune response contribution to the larval immunity.

  10. Spore stage expression of a vegetative insecticidal gene increase toxicity of Bacillus thuringiensis subsp. aizawai SP41 against Spodoptera exigua.

    PubMed

    Thamthiankul Chankhamhaengdecha, S; Tantichodok, A; Panbangred, Watanalai

    2008-09-10

    To enhance the toxicity of the Bacillus thuringiensis subsp. aizawai strain SP41 (SP41), the vegetative insecticidal protein (Vip) gene vip3A from SP41 was redirected to the sporulation stage by replacing its native promoter with the strong promoter P19 of the cry11Aa operon. Compared to the wild type, SP41 with PVIP (vip3A with its native promoter and ter) had the relative expression ratios of 457, 548, and 290 at 8, 14, and 20 h of cultivation, respectively, as measured by quantitative reverse transcription polymerase chain reaction (PCR). SP41 transformed by P19VIP (vip3A controlled by P19 promoter with vip3A ter) showed higher expressions (23, 2055, 1831) at the same time points. SP41 with P19VIP20 (vip3A controlled by P19 promoter and containing P20 and operon ter) had the lowest expression levels (3, 11, 9) at any time point. SDS-PAGE analysis of proteins in the culture supernatant of the P19VIP at 8, 14, and 20 h demonstrated a significant increase in Vip3A at the sporulation stage. Using the surface contamination bioassay, the 50% lethal concentration (LC(50)) of whole culture of PVIP, P19VIP, and P19VIP20 at 20 and 48 h of cultivation against Spodoptera exigua larvae were (68.3, 21.2, and 60.2 microg cm(-2)) and (69.8, 41.8, and 74.6 microg cm(-2)), respectively, compared with 86.6 and 104.4 microg cm(-2) for SP41. The results showed that Vip from P19VIP, expressed at spore stage at 20 and 48 h, can increase the toxicity of SP41 for 4.1- and 2.5-fold, respectively.

  11. Effective dominance of resistance of Spodoptera frugiperda to Bt maize and cotton varieties: implications for resistance management.

    PubMed

    Horikoshi, Renato J; Bernardi, Daniel; Bernardi, Oderlei; Malaquias, José B; Okuma, Daniela M; Miraldo, Leonardo L; Amaral, Fernando S de A E; Omoto, Celso

    2016-10-10

    The resistance of fall armyworm (FAW), Spodoptera frugiperda, has been characterized to some Cry and Vip3A proteins of Bacillus thuringiensis (Bt) expressed in transgenic maize in Brazil. Here we evaluated the effective dominance of resistance based on the survival of neonates from selected Bt-resistant, heterozygous, and susceptible (Sus) strains of FAW on different Bt maize and cotton varieties. High survival of strains resistant to the Cry1F (HX-R), Cry1A.105/Cry2Ab (VT-R) and Cry1A.105/Cry2Ab/Cry1F (PW-R) proteins was detected on Herculex, YieldGard VT PRO and PowerCore maize. Our Vip3A-resistant strain (Vip-R) exhibited high survival on Herculex, Agrisure Viptera and Agrisure Viptera 3 maize. However, the heterozygous from HX-R × Sus, VT-R × Sus, PW-R × Sus and Vip-R × Sus had complete mortality on YieldGard VT PRO, PowerCore, Agrisure Viptera, and Agrisure Viptera 3, whereas the HX-R × Sus and Vip-R × Sus strains survived on Herculex maize. On Bt cotton, the HX-R, VT-R and PW-R strains exhibited high survival on Bollgard II. All resistant strains survived on WideStrike, but only PW-R and Vip-R × Sus survived on TwinLink. Our study provides useful data to aid in the understanding of the effectiveness of the refuge strategy for Insect Resistance Management of Bt plants.

  12. Inheritance of Cry1F resistance, cross-resistance and frequency of resistant alleles in Spodoptera frugiperda (Lepidoptera: Noctuidae).

    PubMed

    Vélez, A M; Spencer, T A; Alves, A P; Moellenbeck, D; Meagher, R L; Chirakkal, H; Siegfried, B D

    2013-12-01

    Transgenic maize, Zea maize L., expressing the Cry1F protein from Bacillus thuringiensis has been registered for Spodoptera frugiperda (J. E. Smith) control since 2003. Unexpected damage to Cry1F maize was reported in 2006 in Puerto Rico and Cry1F resistance in S. frugiperda was documented. The inheritance of Cry1F resistance was characterized in a S. frugiperda resistant strain originating from Puerto Rico, which displayed >289-fold resistance to purified Cry1F. Concentration-response bioassays of reciprocal crosses of resistant and susceptible parental populations indicated that resistance is recessive and autosomal. Bioassays of the backcross of the F1 generation crossed with the resistant parental strain suggest that a single locus is responsible for resistance. In addition, cross-resistance to Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba, Cry2Aa and Vip3Aa was assessed in the Cry1F-resistant strain. There was no significant cross-resistance to Cry1Aa, Cry1Ba and Cry2Aa, although only limited effects were observed in the susceptible strain. Vip3Aa was highly effective against susceptible and resistant insects indicating no cross-resistance with Cry1F. In contrast, low levels of cross-resistance were observed for both Cry1Ab and Cry1Ac. Because the resistance is recessive and conferred by a single locus, an F1 screening assay was used to measure the frequency of Cry1F-resistant alleles from populations of Florida and Texas in 2010 and 2011. A total frequency of resistant alleles of 0.13 and 0.02 was found for Florida and Texas populations, respectively, indicating resistant alleles could be found in US populations, although there have been no reports of reduced efficacy of Cry1F-expressing plants.

  13. Enhancement of supercooling capacity and survival by cold acclimation, rapid cold and heat hardening in Spodoptera exigua.

    PubMed

    Zheng, Xialin; Cheng, Wenjie; Wang, Xiaoping; Lei, Chaoliang

    2011-12-01

    Insects can increase their resistance to cold stress by prior exposure to non-lethal cold temperatures. Here, we investigated the supercooling capacity and survival of eggs, 3rd and 5th instar larvae, and pupae of Spodoptera exigua (Lepidoptera: Noctuidae) during CA, and responses to various pre-treatment protocols, including constant temperatures, thermoperiods, and RCH, RHH, RCH+RHH and RHH+RCH combined with thermoperiods. Only acclimated eggs demonstrated a significant decrease in SCP, from -20.7±0.3 to -22.9±0.3°C, among all experimental groups compared to non-acclimated stages. Survival increased by 17.5% for eggs, 40.0% and 13.3% for 3rd and 5th instar larvae, and by 20.0% for pupae after CA. Compared to controls, survival of eggs under the conditions of thermoperiod (5:15°C), thermoperiod (5:15°C)+RHH, and thermoperiod (5:15, 10:20, and 15:25°C)+RCH significantly increased. In addition, survival of 3rd and 5th instar larvae and pupae increased under the conditions of thermoperiod (5:15°C) and thermoperiod (5:15°C)+RCH, possibly due to the induction of heat shock proteins or cryoprotectants. However, the pre-treatments of thermoperiod+RCH+RHH and thermoperiod+RHH+RCH did not significantly enhance survival of any developmental stage. These adaptive responses may allow S. exigua to enhance supercooling capacity and survival in response to seasonal or unexpected diurnal decreases in environmental temperatures.

  14. A cytochrome P450 gene plays a role in the recognition of sex pheromones in the tobacco cutworm, Spodoptera litura.

    PubMed

    Feng, B; Zheng, K; Li, C; Guo, Q; Du, Y

    2017-08-01

    Cytochrome P450 (P450 or CYP) genes are involved in fundamental physiological functions, and might be also associated with the olfactory recognition of sex pheromones in beetles and moths. A P450 gene, Spodoptera litura CYP4L4 (SlituCYP4L4), was cloned for the first time from the antennae of S. litura. SlituCYP4L4 was almost exclusively expressed in the adult stage and predominantly expressed in the adult antennae. In situ hybridization showed that SlituCYP4L4 localized mainly at the base of the long sensilla trichoidea, which responds to sex pheromone components. Pretreatment with an S. litura sex pheromone significantly reduced the expression levels of SlituCYP4L4, consistent with other genes involved in sex pheromone recognition. The expression level of SlituCYP4L4 was different in moths collected with different ratios of sex pheromone lures and collected in different geographical locations. After gene knockdown of SlituCYP4L4 in the antennae, the electroantennogram (EAG) responses of male and female moths to (9Z,11E)-tetradecadienyl acetate or (9Z,12E)-tetradecadienyl acetate were significantly decreased. In contrast, EAG responses to plant volatiles and sex pheromones of other moth species were not significantly influenced in these moths. SlituCYP4L4 was also expressed in the gustatory tissues and sensilla, which suggests that SlituCYP4L4 may have other functions in the chemosensory system. Our results have shown for the first time the function of a CYP gene with appendage-specific expression in insect sex pheromone recognition, especially in adult moths. © 2017 The Royal Entomological Society.

  15. Knockout of a P-glycoprotein gene increases susceptibility to abamectin and emamectin benzoate in Spodoptera exigua.

    PubMed

    Zuo, Y-Y; Huang, J-L; Wang, J; Feng, Y; Han, T-T; Wu, Y-D; Yang, Y-H

    2017-07-28

    P-glycoprotein [P-gp or the ATP-binding cassette transporter B1 (ABCB1)] is an important participant in multidrug resistance of cancer cells, yet the precise function of this arthropod transporter is unknown. The aim of this study was to determine the importance of P-gp for susceptibility to insecticides in the beet armyworm (Spodoptera exigua) using clustered regularly interspaced short palindromic repeats/CRISPR-associated 9 (CRISPR/Cas9) gene-editing technology. We cloned an open reading frame (ORF) encoding the S. exigua P-gp protein (SeP-gp) predicted to display structural characteristics common to P-gp and other insect ABCB1 transporters. A knockout line with a frame shift deletion of four nucleotides in the SeP-gp ORF was established using the CRISPR/Cas9 gene-editing system to test its potential role in determining susceptibility to chemical insecticides or insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). Results from comparative bioassays demonstrate that knockout of SeP-gp significantly increases susceptibility of S. exigua by around threefold to abamectin and emamectin benzoate (EB), but not to spinosad, chlorfenapyr, beta-cypermethrin, carbosulfan indoxacarb, chlorpyrifos, phoxim, diafenthiuron, chlorfluazuron, chlorantraniliprole or two Bt toxins (Cry1Ca and Cry1Fa). Our data support an important role for SeP-gp in susceptibility of S. exigua to abamectin and EB and imply that overexpression of SeP-gp may contribute to abamectin and EB resistance in S. exigua. © 2017 The Royal Entomological Society.

  16. Characterization of Spodoptera litura (Lepidoptera: Noctuidae) Takeout Genes and Their Differential Responses to Insecticides and Sex Pheromone