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Sample records for pseudococcus longispinus targioni-tozzetti

  1. Description of a new soft scale insect of the genus Pulvinaria Targioni Tozzetti (Hemiptera, Coccoidea, Coccidae) from Bogota, Colombia

    PubMed Central

    Tanaka, Hirotaka; Kondo, Takumasa

    2015-01-01

    Abstract A new soft scale (Hemiptera: Coccoidea: Coccidae) species, Pulvinaria caballeroramosae Tanaka & Kondo, sp. n., is described from specimens collected on twigs of Ficus soatensis Dugand (Moraceae) in Bogota, Colombia. The new species resembles Pulvinaria drymiswinteri Kondo & Gullan, described from Chile on Drimys winteri J.R. Forst. & G. Forst. (Winteraceae), but differs in the distribution of preopercular pores on the dorsum, the presence of dorsal tubular ducts, dorsal microducts, and reticulation on the anal plates; and in its feeding habits, i.e., Pulvinaria caballeroramosae feeds on the twigs whereas Pulvinaria drymiswinteri feeds on the leaves of its host. A key to the Colombian species of Pulvinaria Targioni Tozzetti is provided. PMID:25829845

  2. Pheromone-based monitoring of Pseudococcus maritimus (Hemiptera: Pseudococcidae) populations in concord grape vineyards.

    PubMed

    Bahder, B W; Naidu, R A; Daane, K M; Millar, J G; Walsh, D B

    2013-02-01

    The grape mealybug, Pseudococcus maritimus (Ehrhorn), is the dominant mealybug in Washington's Concord grape vineyards (Vitis labrusca L.). It is a direct pest of fruit clusters and a vector of grapevine leafroll-associated viruses. Using traps baited with the sex pheromone of Ps. maritimus, we determined the optimal trap density for monitoring Ps. maritimus, with the goal of providing a more rapid monitoring method for Ps. maritimus than visual surveys. Varying densities of pheromone-baited traps (one, four, and eight traps per 12.14 ha) were deployed in Concord vineyards to monitor Ps. maritimus seasonal phenology in 2010 and 2011. In both years, flights of adult males were detected in early May and captures peaked twice per season in mid-June and mid-August, indicating two generations each year. Trap data were analyzed using Taylor's Power Law, Iwao's patchiness regression, and the K parameter of the negative binomial model to determine optimal sample size. The formula using the K parameter provided the lowest required sample size, showing that four to eight traps per 12.14 ha were needed to provide 30% sampling precision efficiency throughout the entire season. Fewer traps were needed during flight peaks when trap capture numbers were great. Only one pheromone-baited trap per 12.14 ha was sufficient to provide Ps. maritimus flight phenology data to make informed management decisions. Species-specific pheromone-baited traps deployed for Planococcus ficus (Signoret), Pseudococcus longispinus (Targioni Tozzetti), and Pseudococcus viburni (Signoret) did not detect any of these species in the vineyards sampled. PMID:23448065

  3. Pheromone-baited traps for assessment of seasonal activity and population densities of mealybug species (Hemiptera: Pseudococcidae) in nurseries producing ornamental plants.

    PubMed

    Waterworth, Rebeccah A; Redak, Richard A; Millar, Jocelyn G

    2011-04-01

    Operational parameters of traps baited with the pheromones of three mealybug species were optimized in nurseries producing ornamental plants. All pheromone doses (1-320 microg) attracted Pseudococcus longispinus (Targioni Tozzetti) and Pseudococcus viburni (Signoret) males, with the lowest dose (1 microg) attracting the fewest males for both species. Doses of 3.2-100 microg were as attractive to male P. longispinus as the highest dose (320 microg); doses from 10 to 320 microg were equally attractive for P. viburni males. Lures containing 25-microg doses of either pheromone had effective field lifetimes of at least 12 wk. Experiments were performed to test the efficacy of combining multiple pheromones to attract several species of mealybugs simultaneously. Lures loaded with a mixture of the pheromones of P. longispinus, P. viburni, and Planococcus citri (Risso) were as attractive to P. viburni and P. citri as lures with their individual pheromones. Response of P. longispinus to the blend was decreased by 38% compared with its pheromone as a single component. A subsequent trial with two-component blends showed that the pheromone ofP. citri was responsible for this modest decrease in P. longispinus response. This should not affect the overall efficacy of using these lures for monitoring the presence of all three mealybug species simultaneously. Pheromone traps were used to detect infestations of P. longispinus throughout the season and to track population cycles. When pheromone-baited traps for P. longispinus were compared with manual sampling, trap counts of male mealybugs were significantly correlated with mealybugs counted on plants in the vicinity of the traps. PMID:21510204

  4. Molecular and morphological characterization of mealybugs (Hemiptera: Pseudococcidae) from Chilean vineyards.

    PubMed

    Correa, M C G; Germain, J-F; Malausa, T; Zaviezo, T

    2012-10-01

    Mealybugs are major pests of grapevines worldwide. They cause economic losses by lowering the cosmetic value of fruits, reducing yields, transmitting viruses and resulting in the quarantine or rejection of produce in international trade. Knowledge of the species present in a vineyard is important for the adjustment of management strategies. We surveyed and accurately characterized the mealybugs infesting vineyards in one of the main production areas of Chile; 164 mealybugs were sampled from 26 vineyards in four regions of Chile and identified by DNA sequencing for two markers (cytochrome oxidase I and internal transcribed spacer 2) and morphological examination. Pseudococcus viburni (Signoret) was the most common species, followed by Pseudococcus meridionalis Prado and Pseudococcus cribata González. Molecular variability at the COI and ITS2 loci was observed in both P. viburni and P. cribata. A comparison of haplotypes of P. viburni worldwide provides support for a recent hypothesis that this species is native to South America, a finding with direct consequences for management. Neither Pseudococcus longispinus (Targioni & Tozzetti) nor Planococcus ficus Signoret were found. PMID:22361038

  5. Identification of mealybug pest species (Hemiptera: Pseudococcidae) in Egypt and France, using a DNA barcoding approach.

    PubMed

    Abd-Rabou, S; Shalaby, H; Germain, J-F; Ris, N; Kreiter, P; Malausa, T

    2012-10-01

    Pseudococcidae (mealybugs) is a large taxonomic group, including a number of agronomic pests. Taxonomic identification of mealybug species is a recurrent problem and represents a major barrier to the establishment of adequate pest management strategies. We combined molecular analysis of three DNA markers (28S-D2, cytochrome oxidase I and internal transcribed spacer 2) with morphological examination, for the identification of 176 specimens collected from 40 mealybug populations infesting various crops and ornamental plants in Egypt and France. This combination of DNA and morphological analyses led to the identification of 17 species: seven in Egypt (Planococcus citri (Risso), Planococcus ficus (Signoret), Maconellicoccus hirsutus (Green), Ferrisia virgata (Cockerell), Phenacoccus solenopsis Tinsley, Phenacoccus parvus Morrison and Saccharicoccus sacchari (Cockerell)) and 11 in France (Planococcus citri, Pseudococcus viburni Signoret, Pseudococcus longispinus (Targioni-Tozzetti), Pseudococcus comstocki (Kuwana), Rhizoecus amorphophalli Betrem, Trionymus bambusae (Green), Balanococcus diminutus (Leonardi), Phenacoccus madeirensis Green, Planococcus vovae (Nasonov), Dysmicoccus brevipes (Cockerell) and Phenacoccus aceris Signoret), Pl. citri being found in both countries. We also found genetic variation between populations considered to belong to the same species, justifying further investigation of the possible occurrence of complexes of cryptic taxa. PMID:22360997

  6. Natural enemies of three mealybug species (Hemiptera: Pseudococcidae) found on citrus and effects of some insecticides on the mealybug parasitoid Coccidoxenoides peregrinus (Hymenoptera: Encyrtidae) in South Africa.

    PubMed

    Wakgari, W M; Giliomee, J H

    2003-06-01

    The population density of mealybug species in some South African citrus orchards has increased to pest status in recent years. The characterization of the natural enemy complex and quantification of their contribution to the control of Planococcus citri (Risso), Pseudococcus longispinus (Targioni-Tozzetti) and Pseudococcus calceolariae (Maskell) on Citrus limon (L.) and Citrus reticulata (Blanco) was investigated through intensive sampling. Eight primary and four secondary parasitoids, and two predator species were identified from P. citri and P. calceolariae. Anagyrus pseudococci (Girault) and Coccidoxenoides peregrinus (Timberlake) were the most common species, accounting for 44% and 21% of the total. Of the five primary parasitoids reared from P. longispinus, A. pseudococci and Anagyrus sp. were predominant, comprising 41% and 30%. Nymphal and adult parasitism (range = 0-26% vs. 0-66%) and predation (range = 0-5.6% vs. 0-4.1%) varied significantly between host trees and mealybug species (P < 0.001). The numbers of nymphal instars and adult stages of P. calceolariae and P. longispinus and the nymphal stage of P. citri that were parasitized and killed by predators correlated significantly with the total number of hosts on which they acted (P < 0.01), suggesting a density-dependent association. Laboratory bioassay of nine contact insecticides (methidathion, methomyl, methyl-parathion, parathion, profenofos and prothiofos) against C. peregrinus indicated that all were highly toxic, causing 98-100% mortality in < 6 h of treatment. The IGRs fenoxycarb and triflumuron did not cause significant parasitoid mortality (P > 0.05). However, a mixture of pyriproxyfen and mineral oil caused a marginally significant mortality (P < 0.05). PMID:12762866

  7. Mealybug species from Chilean agricultural landscapes and main factors influencing the genetic structure of Pseudococcus viburni.

    PubMed

    Correa, Margarita C G; Lombaert, Eric; Malausa, Thibaut; Crochard, Didier; Alvear, Andrés; Zaviezo, Tania; Palero, Ferran

    2015-01-01

    The present study aimed to characterize the distribution of mealybug species along Chilean agro-ecosystems and to determine the relative impact of host plant, management strategy, geography and micro-environment on shaping the distribution and genetic structure of the obscure mealybug Pseudococcus viburni. An extensive survey was completed using DNA barcoding methods to identify Chilean mealybugs to the species level. Moreover, a fine-scale study of Ps. viburni genetic diversity and population structure was carried out, genotyping 529 Ps. viburni individuals with 21 microsatellite markers. Samples from 16 localities were analyzed using Bayesian and spatially-explicit methods and the genetic dataset was confronted to host-plant, management and environmental data. Chilean crops were found to be infested by Ps. viburni, Pseudococcus meridionalis, Pseudococcus longispinus and Planococcus citri, with Ps. viburni and Ps. meridionalis showing contrasting distribution and host-plant preference patterns. Ps. viburni samples presented low genetic diversity levels but high genetic differentiation. While no significant genetic variance could be assigned to host-plant or management strategy, climate and geography were found to correlate significantly with genetic differentiation levels. The genetic characterization of Ps. viburni within Chile will contribute to future studies tracing back the origin and improving the management of this worldwide invader. PMID:26559636

  8. Mealybug species from Chilean agricultural landscapes and main factors influencing the genetic structure of Pseudococcus viburni

    PubMed Central

    Correa, Margarita C. G.; Lombaert, Eric; Malausa, Thibaut; Crochard, Didier; Alvear, Andrés; Zaviezo, Tania; Palero, Ferran

    2015-01-01

    The present study aimed to characterize the distribution of mealybug species along Chilean agro-ecosystems and to determine the relative impact of host plant, management strategy, geography and micro-environment on shaping the distribution and genetic structure of the obscure mealybug Pseudococcus viburni. An extensive survey was completed using DNA barcoding methods to identify Chilean mealybugs to the species level. Moreover, a fine-scale study of Ps. viburni genetic diversity and population structure was carried out, genotyping 529 Ps. viburni individuals with 21 microsatellite markers. Samples from 16 localities were analyzed using Bayesian and spatially-explicit methods and the genetic dataset was confronted to host-plant, management and environmental data. Chilean crops were found to be infested by Ps. viburni, Pseudococcus meridionalis, Pseudococcus longispinus and Planococcus citri, with Ps. viburni and Ps. meridionalis showing contrasting distribution and host-plant preference patterns. Ps. viburni samples presented low genetic diversity levels but high genetic differentiation. While no significant genetic variance could be assigned to host-plant or management strategy, climate and geography were found to correlate significantly with genetic differentiation levels. The genetic characterization of Ps. viburni within Chile will contribute to future studies tracing back the origin and improving the management of this worldwide invader. PMID:26559636

  9. Potential of temperature, controlled atmospheres, and ozone fumigation to control thrips and mealybugs on ornamental plants for export.

    PubMed

    Hollingsworth, Robert G; Armstrong, John W

    2005-04-01

    Ozone (O3) fumigation is a potential quarantine treatment alternative for controlling stored-product pests and surface insect pests on fresh agricultural commodities. We explored the effects of temperature, treatment time, controlled atmospheres, and vacuum in combination with O3 to control two important pests of ornamental crops: western flower thrips, Frankliniella occidentalis (Pergande), and longtailed mealybug, Pseudococcus longispinus Targioni Tozzetti. Treatment parameters tested were O3 concentrations from 0 to 3,800 ppm, treatment durations were from 30 to 120 min, vacuums were from 0 to 0.41 bar below ambient, temperatures were from 32.2 to 40.6 degrees C, and controlled atmospheres were composed primarily of nitrogen, carbon dioxide, or breathing air [BA]. Treatment efficacy was enhanced by higher O3 concentration and temperature, lower oxygen, and longer treatment times. Reduced pressure was not an important factor. Mealybugs were more difficult to kill than thrips. A 30-min treatment of O3 at approximately 200 ppm in 100% CO2 at 37.8 degrees C killed 47.9 and 98.0% of mealybugs and adult female thrips, respectively. All of the ornamentals tested were damaged to some degree by O3 treatments. However, crops with thick leaves such as orchids exhibited little damage, and the waxy portions of certain flowers were not damaged. The results suggest that O3 has potential as a quarantine treatment to control thrips and mealybugs on selected commodities. PMID:15889716

  10. Activity of an essential oil derived from Chenopodium ambrosioides on greenhouse insect pests.

    PubMed

    Cloyd, Raymond A; Chiasson, Helene

    2007-04-01

    This study involved both greenhouse and laboratory experiments evaluating the effect of an essential oil product (QRD 400) derived from Chenopodium ambrosioides variety nr. Ambrosioides L. (Chenopodiaceae) on greenhouse insect pests that feed on different plant parts: citrus mealybug, Planococcus citri (Risso); longtailed mealybug, Pseudococcus longispinus (Targioni Tozzetti); western flower thrips, Frankliniella occidentalis (Pergande), and fungus gnats (Bradysia spp.). Treatments were applied to coleus, Solenostemon scutellarioides plants; transvaal daisy, Gerbera jamesonii flowers; or growing medium, depending on the insect pest. The essential oil was most effective, based on adult emergence, on both the second and third instars of the fungus gnat Bradysia sp. nr. coprophila when applied as a drench to growing medium. In addition, there was a significant rate response for QRD 400 on fungus gnats. The QRD 400 treatment had the highest percentage of mortality on longtailed mealybug (55%) compared with the other treatments. However, the essential oil was less effective against citrus mealybug (3% mortality) and western flower thrips adults (18-34% mortality) compared with standard insecticides, such as acetamiprid (TriStar) and spinosad (Conserve), which are typically used by greenhouse producers. This lack of efficacy may be associated with volatility and short residual properties of the essential oil or with the essential oil taking longer to kill insect pests. Other insecticides and miticides evaluated, including sesame oil, garlic, paraffinic oil, and Bacillus thuringiensis subsp. israelensis, provided minimal control of the designated insect pests. In addition, adult rove beetle Atheta coriaria Kraatz adults were not effective in controlling the larval instars of fungus gnats when applied at a rate of five adults per container. PMID:17461071

  11. A Survey of Scale Insects (Sternorryncha: Coccoidea) Occurring on Table Grapes in South Africa

    PubMed Central

    Walton, Vaughn M.; Krüger, Kerstin; Saccaggi, Davina L.; Millar, Ian M.

    2009-01-01

    Increasing international trade and tourism have led to an increase in the introduction of exotic pests that pose a considerable economic threat to the agro-ecosystems of importing countries. Scale insects (Sternorryncha: Coccoidea) may be contaminants of export consignments from the South African deciduous fruit industry to the European Union, Israel, United Kingdom and the United States, for example. Infestations of immature scale insects found on South African fruit destined for export have resulted in increasing rates of rejection of such consignments. To identify the risk posed by scale insect species listed as phytosanitary pests on table grapes to the abovementioned importing countries, a field survey was undertaken in 2004–2005 in vineyards throughout all grape-producing regions in South Africa. Coccoidea species found during the current field survey were Planococcus ficus (Signoret), Pseudococcus longispinus (Targioni Tozzetti), Coccus hesperidum L. and Nipaecoccus viridis (Newstead). With the exception of Pl. ficus, which has only been collected from Vitis vinifera (Vitaceae) and Ficus carica (Moraceae) in South Africa, these species are polyphagous and have a wide host range. None of the scale insect species found to occur in vineyards in South Africa pose a phytosanitary risk to countries where fruit are exported except for Ferrisia malvastra (McDaniel) and N. viridis that have not been recorded in the USA. All scale insects previously found in vineyards in South Africa are listed and their phytosanitary status discussed. The results of the survey show that the risk of exporting scale insect pests of phytosanitary importance on table grapes from South Africa is limited. PMID:20050816

  12. A new mealybug in the genus Pseudococcus Westwood (Hemiptera: Coccomorpha: Pseudococcidae) from North America, with a key to species of Pseudococcus from the New World.

    PubMed

    Ellenrieder, Natalia Von; Watson, Gillian

    2016-01-01

    A mealybug species that feeds on Agave spp., Pseudococcus variabilis sp. n. (Hemiptera: Coccomorpha: Pseudococcidae), is described from North America. Its entry into the United States was likely via the horticultural trade on its host plants in the genus Agave (Liliales: Agavaceae). Descriptions and illustrations of the adult female and male, diagnosis from congeners in the New World, and a molecular characterization based on COI are provided, as well as a key to adult females of all Pseudococcus species recorded from the New World. PMID:27394765

  13. Longspine Sandbur, Cenchrus longispinus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Longspine sandbur found in the Pacific Northwest is a warm-season, annual grass that may behave as a perennial in areas with mild winters. It disperses primarily by attachment of seed to humans, animals, and equip¬ment. Sandbur is a North American native that has spread northward from its subtropica...

  14. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France

    PubMed Central

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M. Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  15. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France.

    PubMed

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  16. Monitoring Pseudococcus calceolariae (Hemiptera: Pseudococcidae) in Fruit Crops Using Pheromone-Baited Traps.

    PubMed

    Flores, M Fernanda; Romero, Alda; Oyarzun, M Soledad; Bergmann, Jan; Zaviezo, Tania

    2015-10-01

    The citrophilus mealybug, Pseudococcus calceolariae (Maskell), is an important pest of fruit crops in many regions of the world. Recently, its sex pheromone has been identified and synthesized. We carried out field experiments with the goal of developing monitoring protocols for P. calceolariae using pheromone-baited traps. Traps checked hourly for 24 hours showed a distinct diel pattern of male flight, between 18:00 and 21:00 h. The presence of unnatural stereoisomers did not affect trap captures, with isomeric mixtures capturing similar amounts of males as the biological active isomer. Dose of isomeric mixture pheromone (0-100 µg) had a nonlinear effect on male captures, with 10, 30, and 50 µg capturing similar amounts. The effective range of pheromone traps was determined by placing traps at different distances (15, 40, and 80 m) from an infested blueberry field, loaded with 0, 1 and 25 µg of the pheromone. For all distances, 25 µg dose captured more males, and was highly attractive up to 40 m. There was a significant effect of lure age on male captures (0-150 d), with similar amount of males captured up to 90-day-old lure, and lower captures in the 150-day-old lure compared with fresh ones. We found significant positive correlations between P. calceolariae males caught in pheromone traps with female abundance and fruit infestation at harvest. Our results show the usefulness of P. calceolariae pheromones for monitoring at field level and provide information for the design of monitoring protocols. PMID:26453728

  17. Characterization of microsatellite DNA libraries from three mealybug species and development of microsatellite markers for Pseudococcus viburni (Hemiptera: Pseudococcidae).

    PubMed

    Correa, M C G; Zaviezo, T; Le Maguet, J; Herrbach, E; Malausa, T

    2014-04-01

    Mealybugs (Hemiptera: Pseudococcidae) are important pests for crops worldwide. Different species, cryptic taxa under the same species name or even populations within a species can differ in biological characteristics, such as phenology, resistance to insecticides, virus transmission and susceptibility to natural enemies. Therefore, their management efficacy depends on their accurate identification. Microsatellite genetic markers are efficient in revealing the fine-scale taxonomic status of insects, both at inter- and intra-specific level. Despite their potential uses, microsatellites have been developed only for one mealybug species so far. Hence, it is unclear whether microsatellites may be useful to assess mealybug population differentiation and structuring. In this work, we tested the feasibility of developing microsatellite markers in mealybugs by: (i) producing and characterizing microsatellite DNA libraries for three species: Pseudococcus viburni, Pseudococcus comstocki and Heliococcus bohemicus, and (ii) by developing and testing markers for Ps. viburni. The obtained libraries contained balanced percentages of dinucleotide (ranging from 15 to 25%) and trinucleotide (from 5 to 17%) motifs. The marker setup for Ps. viburni was successful, although 70% of the primers initially tested were discarded for a lack of polymorphism. Finally, 25 markers were combined in two multiplex polymerase chain reactions with 21 displaying no evidence of deviation from Hardy-Weinberg equilibrium. Ps. viburni markers were tested on one population from France and one from Chile. The markers revealed a significant genetic differentiation between the two populations with an Fst estimate of 0.266. PMID:24345408

  18. INSECTICIDAL ACTIVITY OF PROTEIN EXTRACTS OBTAINED FROM BULBS OF CHILEAN AMARYLLIDACEAE AGAINST TRIALEURODES VAPORARIORUM WESTWOOD AND PSEUDOCOCCUS VIBURNI SIGNORET.

    PubMed

    Zapata, N; Vargas, M; Coronado, A; Van Damme, E J M; Smagghe, G

    2015-01-01

    Entomotoxic proteins are produced by plants in defence against insect herbivory. Some carbohydrate-binding proteins exhibit strong insecticidal activity affecting the survival, growth, development and feeding behavior of phytophagous insects. The occurrence of entomotoxic lectins is well documented in the Amaryllidaceae, a plant family spread world-wide. In Chile, this family is represented by numerous species, many of which are also of high ornamental value. Protein extracts were obtained from bulbs of five different species of Chilean Amaryllidaceae. A dose-response assay was carried out with two important pests: the greenhouse whitefly Trialeurodes vaporariorum Westwood and the mealybug Pseudococcus viburni Signoret. The extracts were offered to insects in a liquid artificial diet for three days and the mortality was scored. The Phycella australis Ravenna extract caused the highest insecticidal activity (T. vaporariorum LC₅₀: 7200 µg/mL; P. viburni LC₅₀: 9500 µg/mL). Applied at 1000 µg/mL in the diet the P. australis extract did not repel feeding of these pests. A mannose-binding lectin isolated from the bulbs of P. australis proved to be moderately toxic for these pests (T. vaporariorum LC₅₀: 1127 µg/mL; P. viburni LC₅₀: 2320 µg/mL). PMID:27145586

  19. IRRADIATION AS A PHYTOSANITARY TREATMENT FOR WHITE PEACH SCALE (HOMOPTERA: DIASPIDIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation was examined as a potential phytosanitary treatment to control white peach scale, Pseudaulacaspis pentagona (Targioni-Tozzetti) (Homoptera: Diaspididae), a serious quarantine pest of papaya in Hawaii. Dose response tests were conducted with 2nd stage nymphs, adult females without eggs, a...

  20. Effect of papaya trunk angle on infestation by white peach scale, Pseudaulacaspis pentagona (Hemiptera: Diaspididae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two papaya (Carica papaya L.) seedlings growing in one planting hole often results in angular or non-vertical growth of the trees. Data on trunk angularity, or leaning, (deviation from the vertical line of reference) and white peach scale, Pseudaulacaspis pentagona Targioni-Tozzetti (Hemiptera: Dias...

  1. Slowing the Spread of Grapevine Leafroll-Associated Viruses in Commercial Vineyards With Insecticide Control of the Vector, Pseudococcus maritimus (Hemiptera: Pseudococcidae)

    PubMed Central

    Fuchs, M. F.; Martinson, T.; Hesler, S.; Loeb, G. M.

    2015-01-01

    Vineyards were surveyed for grapevine leafroll-associated viruses and their insect vectors in New York State’s Finger Lakes region in 2006–2008. Grape mealybug, Pseudococcus maritimus (Erhorn) (Hemiptera: Pseudococcidae), European Fruit Lecanium, Parthenolecanium corni (Bouche), and Cottony Maple Scale, Pulvinaria acericola (Walsh and Riley) (Hemiptera: Coccidae) were identified as vector species in this region. An increase in the incidence of Grapevine leafroll-associated virus 1 (GLRaV-1) and GLRaV-3 was observed in 8 of the 20 vineyards surveyed, which implies transmission by these insect vectors. Two of the vineyards for which a temporal increase in disease incidence was documented were then used to evaluate the efficacy of foliar applications of horticultural oil and two classes of insecticides for control of P. maritimus and for slowing virus spread over 2 years of vine protection. Delayed dormant applications of horticultural oil contributed to control of early season crawlers; however, this was not the case for control of summer populations. Applications of acetamiprid and spirotetramat achieved control in summer populations; however, spirotetramat outperformed acetamiprid in percent reduction of treated compared with control vines and in a side-by-side trial. Vines treated with spirotetramat had a lower percentage of new vines testing positive for GLRaV-1 than control vines after 2 years, while no other spray program altered the increase in incidence of GLRaV-1 or -3. PMID:26223949

  2. Slowing the Spread of Grapevine Leafroll-Associated Viruses in Commercial Vineyards With Insecticide Control of the Vector, Pseudococcus maritimus (Hemiptera: Pseudococcidae).

    PubMed

    Wallingford, A K; Fuchs, M F; Martinson, T; Hesler, S; Loeb, G M

    2015-01-01

    Vineyards were surveyed for grapevine leafroll-associated viruses and their insect vectors in New York State's Finger Lakes region in 2006-2008. Grape mealybug, Pseudococcus maritimus (Erhorn) (Hemiptera: Pseudococcidae), European Fruit Lecanium, Parthenolecanium corni (Bouche), and Cottony Maple Scale, Pulvinaria acericola (Walsh and Riley) (Hemiptera: Coccidae) were identified as vector species in this region. An increase in the incidence of Grapevine leafroll-associated virus 1 (GLRaV-1) and GLRaV-3 was observed in 8 of the 20 vineyards surveyed, which implies transmission by these insect vectors. Two of the vineyards for which a temporal increase in disease incidence was documented were then used to evaluate the efficacy of foliar applications of horticultural oil and two classes of insecticides for control of P. maritimus and for slowing virus spread over 2 years of vine protection. Delayed dormant applications of horticultural oil contributed to control of early season crawlers; however, this was not the case for control of summer populations. Applications of acetamiprid and spirotetramat achieved control in summer populations; however, spirotetramat outperformed acetamiprid in percent reduction of treated compared with control vines and in a side-by-side trial. Vines treated with spirotetramat had a lower percentage of new vines testing positive for GLRaV-1 than control vines after 2 years, while no other spray program altered the increase in incidence of GLRaV-1 or -3. PMID:26223949

  3. Molecular-based approach to the differentiation of mealybug (Hemiptera: Pseudococcidae) species.

    PubMed

    Beuning, L L; Murphy, P; Wu, E; Batchelor, T A; Morris, B A

    1999-04-01

    The rDNA internal transcribed spacer (ITS) region of 4 mealybug species, Pseudococcus viburni (Signoret), P. longispinus (Targiono-Tozzetti), P. calceolariae (Maskell), and P. similans (Lidgett), was isolated by polymerase chain reaction (PCR) amplification, cloned, and sequenced. In this region of the genome there were numerous differences, including nucleotide substitutions, insertions, or deletions between P. viburni, P. longispinus, and P. calceolariae, whereas P. calceolariae and P. similans were very similar. Based on sequence differences between the ITS regions, we designed PCR primers that were able to differentiate the 4 mealybug species and that correlated with morphological differences found between adult females of these species. The PCR amplification by using the species-specific primers enabled the differentiation of not only adult females but also eggs, juveniles, and adult males, which was not previously possible by using conventional identification methods. PMID:10333754

  4. Development of a multiplex PCR for identification of vineyard mealybugs.

    PubMed

    Daane, Kent M; Middleton, Mathew C; Sforza, René; Cooper, Monica L; Walton, Vaughn M; Walsh, Douglas B; Zaviezo, Tania; Almeida, Rodrigo P P

    2011-12-01

    A simple molecular tool was developed and tested to identify seven mealybug species found in North American vineyards: Pseudococcus maritimus Ehrhorn, Pseudococcus viburni (Signoret), Pseudococcus longispinus (Targioni-Tozzeti), Pseudococcus calceolariae (Maskell), Planococcus ficus (Signoret), Planococcus citri (Risso), and Ferrisia gilli Gullan. The developed multiplex PCR is based on the mitochondrial cytochrome c oxidase subunit one gene. In tests, this single-step multiplex PCR correctly identified 95 of 95 mealybug samples, representing all seven species and collected from diverse geographic regions. To test the sensitivity, single specimen samples with different Pl. ficus developmental stages (egg to adult female and adult male) were processed PCR and the resulting output provided consistent positive identification. To test the utility of this protocol for adult males caught in sex baited pheromone traps, Pl. ficus adult males were placed in pheromone traps, aged at a constant temperature of 26±2°C, and processed with the multiplex each day thereafter for 8 d. Results showed consistent positive identification for up to 6 d (range, 6-8 d). Results are discussed with respect to the usefulness of this molecular tool for the identification of mealybugs in pest management programs and biosecurity of invasive mealybugs. PMID:22217778

  5. Molecular and histological characterization of primary (betaproteobacteria) and secondary (gammaproteobacteria) endosymbionts of three mealybug species.

    PubMed

    Gatehouse, Laurence N; Sutherland, Paul; Forgie, Shaun A; Kaji, Ryohei; Christeller, John T

    2012-02-01

    Microscopic localization of endosymbiotic bacteria in three species of mealybug (Pseudococcus longispinus, the long-tailed mealybug; Pseudococcus calceolariae, the citrophilus mealybug; and Pseudococcus viburni, the obscure mealybug) showed these organisms were confined to bacteriocyte cells within a bacteriome centrally located within the hemocoel. Two species of bacteria were present, with the secondary endosymbiont, in all cases, living within the primary endosymbiont. DNA from the dissected bacteriomes of all three species of mealybug was extracted for analysis. Sequence data from selected 16S rRNA genes confirmed identification of the primary endosymbiont as "Candidatus Tremblaya princeps," a betaproteobacterium, and the secondary endosymbionts as gammaproteobacteria closely related to Sodalis glossinidius. A single 16S rRNA sequence of the primary endosymbiont was found in all individuals of each mealybug species. In contrast, the presence of multiple divergent strains of secondary endosymbionts in each individual mealybug suggests different evolutionary and transmission histories of the two endosymbionts. Mealybugs are known vectors of the plant pathogen Grapevine leafroll-associated virus 3. To examine the possible role of either endosymbiont in virus transmission, an extension of the model for interaction of proteins with bacterial chaperonins, i.e., GroEL protein homologs, based on mobile-loop amino acid sequences of their GroES homologs, was developed and used for analyses of viral coat protein interactions. The data from this model are consistent with a role for the primary endosymbiont in mealybug transmission of Grapevine leafroll-associated virus 3. PMID:22156418

  6. Molecular and Histological Characterization of Primary (Betaproteobacteria) and Secondary (Gammaproteobacteria) Endosymbionts of Three Mealybug Species

    PubMed Central

    Sutherland, Paul; Forgie, Shaun A.; Kaji, Ryohei; Christeller, John T.

    2012-01-01

    Microscopic localization of endosymbiotic bacteria in three species of mealybug (Pseudococcus longispinus, the long-tailed mealybug; Pseudococcus calceolariae, the citrophilus mealybug; and Pseudococcus viburni, the obscure mealybug) showed these organisms were confined to bacteriocyte cells within a bacteriome centrally located within the hemocoel. Two species of bacteria were present, with the secondary endosymbiont, in all cases, living within the primary endosymbiont. DNA from the dissected bacteriomes of all three species of mealybug was extracted for analysis. Sequence data from selected 16S rRNA genes confirmed identification of the primary endosymbiont as “Candidatus Tremblaya princeps,” a betaproteobacterium, and the secondary endosymbionts as gammaproteobacteria closely related to Sodalis glossinidius. A single 16S rRNA sequence of the primary endosymbiont was found in all individuals of each mealybug species. In contrast, the presence of multiple divergent strains of secondary endosymbionts in each individual mealybug suggests different evolutionary and transmission histories of the two endosymbionts. Mealybugs are known vectors of the plant pathogen Grapevine leafroll-associated virus 3. To examine the possible role of either endosymbiont in virus transmission, an extension of the model for interaction of proteins with bacterial chaperonins, i.e., GroEL protein homologs, based on mobile-loop amino acid sequences of their GroES homologs, was developed and used for analyses of viral coat protein interactions. The data from this model are consistent with a role for the primary endosymbiont in mealybug transmission of Grapevine leafroll-associated virus 3. PMID:22156418

  7. The link between independent acquisition of intracellular gamma-endosymbionts and concerted evolution in Tremblaya princeps

    PubMed Central

    López-Madrigal, Sergio; Latorre, Amparo; Moya, Andrés; Gil, Rosario

    2015-01-01

    Many insect species establish mutualistic symbiosis with intracellular bacteria that complement their unbalanced diets. The betaproteobacterium “Candidatus Tremblaya” maintains an ancient symbiosis with mealybugs (Hemiptera: Pseudococcidae), which are classified in subfamilies Phenacoccinae and Pseudococcinae. Most Phenacoccinae mealybugs have “Candidatus Tremblaya phenacola” as their unique endosymbiont, while most Pseudococcinae mealybugs show a nested symbiosis (a bacterial symbiont placed inside another one) where every “Candidatus Tremblaya princeps” cell harbors several cells of a gammaproteobacterium. Genomic characterization of the endosymbiotic consortium from Planococcus citri, composed by “Ca. Tremblaya princeps” and “Candidatus Moranella endobia,” unveiled several atypical features of the former's genome, including the concerted evolution of paralogous loci. Its comparison with the genome of “Ca. Tremblaya phenacola” PAVE, single endosymbiont of Phenacoccus avenae, suggests that the atypical reductive evolution of “Ca. Tremblaya princeps” could be linked to the acquisition of “Ca. Moranella endobia,” which possess an almost complete set of genes encoding proteins involved in homologous recombination. In order to test this hypothesis, we performed comparative genomics between “Ca. Tremblaya phenacola” and “Ca. Tremblaya princeps” and searched for the co-occurrence of concerted evolution and homologous recombination genes in endosymbiotic consortia from four unexplored mealybug species, Dysmicoccus boninsis, Planococcus ficus, Pseudococcus longispinus, and Pseudococcus viburni. Our results support a link between concerted evolution and nested endosymbiosis. PMID:26161080

  8. The link between independent acquisition of intracellular gamma-endosymbionts and concerted evolution in Tremblaya princeps.

    PubMed

    López-Madrigal, Sergio; Latorre, Amparo; Moya, Andrés; Gil, Rosario

    2015-01-01

    Many insect species establish mutualistic symbiosis with intracellular bacteria that complement their unbalanced diets. The betaproteobacterium "Candidatus Tremblaya" maintains an ancient symbiosis with mealybugs (Hemiptera: Pseudococcidae), which are classified in subfamilies Phenacoccinae and Pseudococcinae. Most Phenacoccinae mealybugs have "Candidatus Tremblaya phenacola" as their unique endosymbiont, while most Pseudococcinae mealybugs show a nested symbiosis (a bacterial symbiont placed inside another one) where every "Candidatus Tremblaya princeps" cell harbors several cells of a gammaproteobacterium. Genomic characterization of the endosymbiotic consortium from Planococcus citri, composed by "Ca. Tremblaya princeps" and "Candidatus Moranella endobia," unveiled several atypical features of the former's genome, including the concerted evolution of paralogous loci. Its comparison with the genome of "Ca. Tremblaya phenacola" PAVE, single endosymbiont of Phenacoccus avenae, suggests that the atypical reductive evolution of "Ca. Tremblaya princeps" could be linked to the acquisition of "Ca. Moranella endobia," which possess an almost complete set of genes encoding proteins involved in homologous recombination. In order to test this hypothesis, we performed comparative genomics between "Ca. Tremblaya phenacola" and "Ca. Tremblaya princeps" and searched for the co-occurrence of concerted evolution and homologous recombination genes in endosymbiotic consortia from four unexplored mealybug species, Dysmicoccus boninsis, Planococcus ficus, Pseudococcus longispinus, and Pseudococcus viburni. Our results support a link between concerted evolution and nested endosymbiosis. PMID:26161080

  9. Molecular and morphological identification of mealybug species (Hemiptera: Pseudococcidae) in Brazilian vineyards.

    PubMed

    Pacheco da Silva, Vitor C; Bertin, Aline; Blin, Aurélie; Germain, Jean-François; Bernardi, Daniel; Rignol, Guylène; Botton, Marcos; Malausa, Thibaut

    2014-01-01

    Mealybugs (Hemiptera: Pseudococcidae) are pests constraining the international trade of Brazilian table grapes. They damage grapes by transmitting viruses and toxins, causing defoliation, chlorosis, and vigor losses and favoring the development of sooty mold. Difficulties in mealybug identification remain an obstacle to the adequate management of these pests. In this study, our primary aim was to identify the principal mealybug species infesting the major table grape-producing regions in Brazil, by morphological and molecular characterization. Our secondary aim was to develop a rapid identification kit based on species-specific Polymerase Chain Reactions, to facilitate the routine identification of the most common pest species. We surveyed 40 sites infested with mealybugs and identified 17 species: Dysmicoccus brevipes (Cockerell), Dysmicoccus sylvarum Williams and Granara de Willink, Dysmicoccus texensis (Tinsley), Ferrisia cristinae Kaydan and Gullan, Ferrisia meridionalis Williams, Ferrisia terani Williams and Granara de Willink, Phenacoccus baccharidis Williams, Phenacoccus parvus Morrison, Phenacoccus solenopsis Tinsley, Planococcus citri (Risso), Pseudococcus viburni (Signoret), Pseudococcus cryptus Hempel, four taxa closely related each of to Pseudococcus viburni, Pseudococcus sociabilis Hambleton, Pseudococcus maritimus (Ehrhorn) and Pseudococcus meridionalis Prado, and one specimen from the genus Pseudococcus Westwood. The PCR method developed effectively identified five mealybug species of economic interest on grape in Brazil: D. brevipes, Pl. citri, Ps. viburni, Ph. solenopsis and Planococcus ficus (Signoret). Nevertheless, it is not possible to assure that this procedure is reliable for taxa that have not been sampled already and might be very closely related to the target species. PMID:25062012

  10. Molecular and Morphological Identification of Mealybug Species (Hemiptera: Pseudococcidae) in Brazilian Vineyards

    PubMed Central

    Pacheco da Silva, Vitor C.; Bertin, Aline; Blin, Aurélie; Germain, Jean-François; Bernardi, Daniel; Rignol, Guylène; Botton, Marcos; Malausa, Thibaut

    2014-01-01

    Mealybugs (Hemiptera: Pseudococcidae) are pests constraining the international trade of Brazilian table grapes. They damage grapes by transmitting viruses and toxins, causing defoliation, chlorosis, and vigor losses and favoring the development of sooty mold. Difficulties in mealybug identification remain an obstacle to the adequate management of these pests. In this study, our primary aim was to identify the principal mealybug species infesting the major table grape-producing regions in Brazil, by morphological and molecular characterization. Our secondary aim was to develop a rapid identification kit based on species-specific Polymerase Chain Reactions, to facilitate the routine identification of the most common pest species. We surveyed 40 sites infested with mealybugs and identified 17 species: Dysmicoccus brevipes (Cockerell), Dysmicoccus sylvarum Williams and Granara de Willink, Dysmicoccus texensis (Tinsley), Ferrisia cristinae Kaydan and Gullan, Ferrisia meridionalis Williams, Ferrisia terani Williams and Granara de Willink, Phenacoccus baccharidis Williams, Phenacoccus parvus Morrison, Phenacoccus solenopsis Tinsley, Planococcus citri (Risso), Pseudococcus viburni (Signoret), Pseudococcus cryptus Hempel, four taxa closely related each of to Pseudococcus viburni, Pseudococcus sociabilis Hambleton, Pseudococcus maritimus (Ehrhorn) and Pseudococcus meridionalis Prado, and one specimen from the genus Pseudococcus Westwood. The PCR method developed effectively identified five mealybug species of economic interest on grape in Brazil: D. brevipes, Pl. citri, Ps. viburni, Ph. solenopsis and Planococcus ficus (Signoret). Nevertheless, it is not possible to assure that this procedure is reliable for taxa that have not been sampled already and might be very closely related to the target species. PMID:25062012

  11. (2,3,4,4-Tetramethylcyclopentyl)methyl acetate, a sex pheromone from the obscure mealybug: first example of a new structural class of monoterpenes.

    PubMed

    Millar, Jocelyn G; Midland, Sharon L; McElfresh, J Steven; Daane, Kent M

    2005-12-01

    The sex pheromone of the obscure mealybug, Pseudococcus viburni, consists of (1R*,2R*,3S*)-(2,3,4,4-tetramethylcyclopentyl)methyl acetate, the first example of a new monoterpenoid structural motif in which the two isoprene units forming the carbon skeleton are joined by 2'-2 and 3'-4 connections rather than the usual 1'-4, head-to-tail connections. This highly irregular terpenoid structure, and the irregular terpenoid structures of related mealybug species, suggest that these insects may have unique terpenoid biosynthetic pathways. PMID:16283090

  12. Three new species of mealybug (Hemiptera, Coccomorpha, Pseudococcidae) on persimmon fruit trees (Diospyros kaki) in southern Brazil.

    PubMed

    Pacheco da Silva, Vitor C; Kaydan, Mehmet Bora; Germain, Jean-François; Malausa, Thibaut; Botton, Marcos

    2016-01-01

    Brazil has the greatest insect diversity in the world; however, little is known about its scale insect species (Hemiptera: Coccomorpha). Mealybugs (Pseudococcidae) have been found in at least 50% of persimmon orchards Diospyros kaki L. in the southern part of the country. In this study three new mealybug species on persimmon trees located in the Serra Gaúcha Region, RS, Brazil, namely, Anisococcus granarae Pacheco da Silva & Kaydan, sp. n., Ferrisia kaki Kaydan & Pacheco da Silva, sp. n. and Pseudococcus rosangelae Pacheco da Silva & Kaydan, sp. n. are described. In addition, an identification key for the genera occurring on fruit orchards and vineyards in Brazil is provided, together with illustrations and molecular data for the new species. PMID:27199595

  13. Three new species of mealybug (Hemiptera, Coccomorpha, Pseudococcidae) on persimmon fruit trees (Diospyros kaki) in southern Brazil

    PubMed Central

    Pacheco da Silva, Vitor C.; Kaydan, Mehmet Bora; Germain, Jean-François; Malausa, Thibaut; Botton, Marcos

    2016-01-01

    Abstract Brazil has the greatest insect diversity in the world; however, little is known about its scale insect species (Hemiptera: Coccomorpha). Mealybugs (Pseudococcidae) have been found in at least 50% of persimmon orchards Diospyros kaki L. in the southern part of the country. In this study three new mealybug species on persimmon trees located in the Serra Gaúcha Region, RS, Brazil, namely, Anisococcus granarae Pacheco da Silva & Kaydan, sp. n., Ferrisia kaki Kaydan & Pacheco da Silva, sp. n. and Pseudococcus rosangelae Pacheco da Silva & Kaydan, sp. n. are described. In addition, an identification key for the genera occurring on fruit orchards and vineyards in Brazil is provided, together with illustrations and molecular data for the new species. PMID:27199595

  14. Microsporidian Parasites Found in the Hemolymph of Four Baikalian Endemic Amphipods

    PubMed Central

    Madyarova, Ekaterina V.; Adelshin, Renat V.; Dimova, Mariya D.; Axenov-Gribanov, Denis V.; Lubyaga, Yulia A.; Timofeyev, Maxim A.

    2015-01-01

    At present, approximately 187 genera and over 1300 species of Microsporidia have been described, among which almost half infect aquatic species and approximately 50 genera potentially infect aquatic arthropods. Lake Baikal is the deepest and one of the oldest lakes in the world, and it has a rich endemic fauna with a predominance of arthropods. Among the arthropods living in this lake, amphipods (Crustacea) are the most dominant group and are represented by more than 350 endemic species. Baikalian amphipods inhabit almost all depths and all types of substrates. The age and geographical isolation of this group creates excellent opportunities for studying the diversity, evolution and genetics of host-parasite relationships. However, despite more than 150 years of study, data investigating the microsporidia of Lake Baikal remain incomplete. In this study, we used molecular genetic analyses to detect microsporidia in the hemolymph of several endemic species of amphipods from Lake Baikal. We provide the first evidence that microsporidian species belonging to three genera (Microsporidium, Dictyocoela and Nosema) are present in the hemolymph of Baikalian endemic amphipods. In the hemolymph of Eulimnogammarus verrucosus, we detected SSU rDNA of microsporidia belonging to the genus Nozema. In the hemolymph of Pallasea cancellous, we found the DNA of Microsporidium sp. similar to that in other Baikalian endemic amphipods; Dictyocoela sp. was found in the hemolymph of Eulimnogammarus marituji and Acanthogammarus lappaceus longispinus. PMID:26087136

  15. Fungus-insect gall of Phlebopus portentosus.

    PubMed

    Zhang, Chun-Xia; He, Ming-Xia; Cao, Yang; Liu, Jing; Gao, Feng; Wang, Wen-Bing; Ji, Kai-Ping; Shao, Shi-Cheng; Wang, Yun

    2015-01-01

    Phlebopus portentosus is a popular edible wild mushroom found in the tropical Yunnan, China, and northern Thailand. In its natural habitats, a gall often has been found on some plant roots, around which fungal fruiting bodies are produced. The galls are different from common insect galls in that their cavity walls are not made from plant tissue but rather from the hyphae of P. portentosus. Therefore we have termed this phenomenon "fungus-insect gall". Thus far six root mealy bug species in the family Pseudococcidae that form fungus-insect galls with P. portentosus have been identified: Formicococcus polysperes, Geococcus satellitum, Planococcus minor, Pseudococcus cryptus, Paraputo banzigeri and Rastrococcus invadens. Fungus-insect galls were found on the roots of more than 21 plant species, including Delonix regia, Citrus maxima, Coffea arabica and Artocarpus heterophyllus. Greenhouse inoculation trials showed that fungus-insect galls were found on the roots of A. heterophyllus 1 mo after inoculation. The galls were subglobose to globose, fulvous when young and became dark brown at maturation. Each gall harbored one or more mealy bugs and had a chimney-like vent for ventilation and access to the gall. The cavity wall had three layers. Various shaped mealy bug wax deposits were found inside the wall. Fungal hyphae invaded the epidermis of plant roots and sometimes even the cortical cells during the late stage of gall development. The identity of the fungus inside the cavity was confirmed by molecular methods. PMID:25344264

  16. Preparation of Mealybugs (Hemiptera: Pseudococcidae) for Genetic Characterization and Morphological Examination.

    PubMed

    Bahder, B W; Bollinger, M L; Sudarshana, M R; Zalom, F G

    2015-01-01

    Mealybugs (Hemiptera: Pseudococcidae) are economically significant agricultural pests on many different crops. Because of their small size and lack of easily visible characters for identification, determination of their taxonomic status is difficult and requires technical competency to prepare a slide-mounted specimen. The standard mounting technique does not allow for analysis of the genome of the specimen. Conversely, preparatory techniques for genetic analysis of mealybugs cause either loss of the entire individual or physical damage that can make morphology-based identification difficult. This study describes a simple protocol that does not impact physical integrity of the specimen for fixation and microscopic examination yet enables simultaneous DNA extraction for DNA-based identification of four mealybug species. All species prepared yielded high quality slide mounts, identified as Planococcus citri Risso, Pseudococcus viburni Signoret, Rhizoecus kondonis Kuwana, or Rhizoecus californicus Ferris. DNA extracted in this manner had higher purity and yield in the final eluate than in samples extracted using standard methods. DNA extracted was successfully amplified by polymerase chain reaction using primers for the cytochrome oxidase I gene and subsequently sequenced for all specimens. This protocol is likely to be applicable to other Hemiptera taxa that are preserved by slide mounting, allowing for both the preparation of a high-quality voucher specimen for morphological identification and simultaneous analysis of DNA for the same specimen. The methods used are technically less challenging than current standard procedures. PMID:26198869

  17. Unusual microtubular patterns and three-dimensional movement of mealybug sperm and sperm bundles.

    PubMed

    Ross, J; Robison, W G

    1969-02-01

    The spermatozoon of the mealybug Pseudococcus obscurus Essig is a filamentous cell (0.25 micro by 300 micro) which exhibits three-dimensional flagellations throughout most of its length. It has microtubules (200 A diameter) and a threadlike nuclear core (0.07-0.09 micro diameter) which extend almost its entire length, but apparently it has no mitochondria, centrioles, typical flagellum, or acrosome. The microtubules are arranged in two and a half concentric rings and total 56 in the most actively motile region but form two or three concentric rings with totals of 28 or 56 tubules, respectively, in less active regions. The relation of unusual microtubular patterns to the 9 + 2 complex and to flagellar motion is discussed. Mealybug spermatozoa are transmitted to the female in motile bundles which are approximately 1.3 micro by 750 micro and have four regions: (1) an anterior corkscrew region; (2) a region which contains approximately 16 spermatozoa; (3) a region of amorphous content; and (4) an endpiece. Bundle motility originates from the synchronous movements of its spermatozoa which appear to be arranged in two concentric multistranded helices. The spermatozoa provide both forward and gyratory motions of the bundle, and the corkscrew complements bundle propulsion by converting part of the rotation into forward movement. PMID:5761921

  18. SYBR(®) Green-based real-time quantitative reverse-transcription PCR for detection and discrimination of grapevine viruses.

    PubMed

    Poojari, Sudarsana; Alabi, Olufemi J; Okubara, Patricia A; Naidu, Rayapati A

    2016-09-01

    A SYBR(®) Green-based real-time quantitative reverse transcription PCR (qRT-PCR) assay in combination with melt-curve analysis (MCA) was optimized for the detection of nine grapevine viruses. The detection limits for simplex qRT-PCR for all nine grapevine viruses were estimated to be in the range of 214-1112 copies of the virus genome. Amplicons with melting temperatures (Tm) separated by at least 2°C in the MCA could differentiate two viruses in the same reaction. Therefore, eight of the nine viruses could be co-diagnosed in five different combinations of duplex assays. Of 305 grape leaf samples from the field or greenhouse, 162 were positive for at least one of the nine grapevine viruses using the duplex qRT-PCR assays. In contrast, only 127 samples were positive using endpoint RT-PCR and PCR assays, indicating the enhanced sensitivity of duplex real-time PCR. In addition, the duplex qRT-PCR assays were be used to detect Grapevine leafroll associated virus 3 (GLRaV-3) in its vector, the grape mealybug (Pseudococcus maritimus Ehrhorn), and Grapevine red blotch-associated virus (GRBaV) in Virginia creeper leafhopper (Erythroneura ziczac Walsh). The simplex and duplex real-time PCR assays developed in this study can be used to examine transmission of co-occruing viruses by insect vectors as well as for rapid and sensitive detection of viruses in infected grapevines. PMID:27246908

  19. New species and geographical records of dactylogyrids (Monogenea) of catfish (Siluriformes) from the Peruvian Amazonia.

    PubMed

    Mendoza-Palmero, Carlos A; Scholz, Tomáš; Mendoza-Franco, Edgar F; Kuchta, Roman

    2012-06-01

    Three new species of gill monogeneans (Dactylogyridae: Ancyrocephalinae) are described from siluriform catfish from Iquitos, Peru: Demidospermus mortenthaleri n. sp. from Brachyplatystoma juruense (Boulenger), Demidospermus brevicirrus n. sp. from Pimelodus sp., and Aphanoblastella aurorae n. sp. from Goeldiella eques (Müller & Troschel). Demidospermus mortenthaleri is characterized by a male copulatory organ (MCO) with a small loop at its middle portion; 2 types of hooks, of which pairs 5 and 6 are longer than the remaining hooks; a proximal subunit round and highly depressed thumb; and a sclerotized vagina with a round pad at the vaginal aperture. Demidospermus brevicirrus is distinguished from other congeners by the presence of a short, straight, and robust MCO and boot-shaped accessory piece with a hooked projection directed posteriorly. Aphanoblastella aurorae is the only species of the genus that possesses an arrow-shaped sclerotized vagina and a medial process on the dorsal bar. Another 6 dactylogyrids described previously are recorded for the first time from the Peruvian Amazonia: Cosmetocleithrum bulbocirrus Kritsky, Thatcher and Boeger, 1986 ; Vancleaveus fungulus Kritsky, Thatcher and Boeger, 1986 ; V. janauacaensis Kritsky, Thatcher and Boeger, 1986 ; V. platyrhynchi Kritsky, Thatcher and Boeger, 1986 ; Unilatus unilatus Mizelle and Kritsky, 1967 ; and U. brittani Mizelle, Kritsky and Crane, 1968 . Based on observations of specimens collected in the Peruvian Amazonia, new morphological data for these species are provided. Comparison of new specimens of U. unilatus and U. brittani with those of Unilatus brevispinus Suriano, 1985 and Unilatus longispinus Suriano, 1985 , both originally described from Brazil, has shown that they are conspecific. Therefore, the latter species were synonymized with U. unilatus and U. brittani , respectively. In addition, 56 undescribed monogeneans found in catfish from the Peruvian Amazonia, some of them probably belonging

  20. Interactions Within Susceptible Hosts Drive Establishment of Genetically Distinct Variants of an Insect-Borne Pathogen.

    PubMed

    Blaisdell, G K; Zhang, S; Bratburd, J R; Daane, K M; Cooper, M L; Almeida, R P P

    2015-08-01

    Coinfections are common, leading to pathogen interactions during transmission and establishment in a host. However, few studies have tested the relative strengths of pathogen interactions in vectors and hosts that determine the outcome of infection. We tested interactions between two genetically distinct variants of the mealybug-transmitted Grapevine leafroll-associated virus 3. The transmission efficiency of each variant in single variant inoculations by two vector species was determined. The effects of vector species, a coinfected source, and simultaneous inoculation from multiple hosts to one host on variant establishment were examined. Within-vector interactions could have a role in transmission from hosts containing mixed infections, but not when vectors were moved from separate singly infected source plants to a single recipient plant. The invasive Planococcus ficus (Signoret) was a more efficient vector than Pseudococcus viburni (Signoret). Transmission efficiency of the two variants did not differ in single variant inoculations. Overall infections were the same whether from singly or coinfected source plants. In mixed inoculations, establishment of one variant was reduced. Mixed inoculations from two singly infected source plants resulted in fewer mixed infections than expected by chance. Therefore, the observed outcome was determined subsequent to host inoculation rather than in the vector. The outcome may be due to resource competition between pathogens. Alternatively apparent competition may be responsible; the pathogens' differential ability to overcome host defenses and colonize the host may determine the final outcome of new infections. Detailed knowledge of interactions between pathogens during transmission and establishment could improve understanding and management of disease spread. PMID:26470292

  1. High-pressure washing treatments to remove obscure mealybug (Homoptera: Pseudococcidae) and lightbrown apple moth (Lepidoptera: Tortricidae) from harvested apples.

    PubMed

    Whiting, D C; Hoy, L E; Maindonald, J H; Connolly, P G; McDonald, R M

    1998-12-01

    Mixed life stages of obscure mealybug, Pseudococcus viburni (Signoret), and late 1st-instar or early 2nd-instar lightbrown apple moth, Epiphyas postvittana (Walker), on 'Royal Gala' apples (Malus domestica Borkhausen) were exposed to standard packhouse processing with and without addition of high-pressure apple washer treatments. Insect removal and mortality were assessed. After standard packhouse processing approximately 60% of P. viburni remained on their host apples. The 2 high-pressure apple washer treatments (500 and 800 psi at 2.0 rods/s) were equally effective and significantly reduced the number of P. viburni on apples compared with the packhouse control. High-pressure apple washer removal by location decreased in the following order: calyx cavity outside the sepals > cheek approximately stem cavity > or = calyx beneath sepals. About half of the E. postvittana larvae infesting apples was removed by standard packhouse processing. Removal rates were similar for all locations on open-calyxed apples. However, no removal occurred from the calyx beneath the sepals if the apple calyx was closed. All 4 high-pressure apple washer treatments tested (500 and 800 psi at 1.0 and 2.0 rods/s) halved the number of larvae on the apple exterior relative to the packhouse control. The pattern of removal for larvae on open-calyxed apples was calyx outside sepals approximately stem cavity > calyx beneath the sepals approximately cheek. A similar pattern was evident for larvae on closed-calyxed apples, except insects beneath the sepals evaded removal. The persistence of insects on the apple cheek reflects the high proportion of larvae inside tunnels in this location compared with other apple locations. Removal of internally positioned insects was much lower than that of externally positioned insects. PMID:9887685

  2. Suppression of insect pest populations and damage to plants by vermicomposts.

    PubMed

    Arancon, Norman Q; Galvis, Paola A; Edwards, Clive A

    2005-07-01

    The effects of commercial vermicomposts, produced from food waste, on infestations and damage by aphids, mealy bugs and cabbage white caterpillars were studied in the greenhouse. Vermicomposts were used at substitution rates into a soil-less plant growth medium, MetroMix 360 (MM360), at rates of 100% MM360 and 0% vermicompost, 80% MM360 and 20% vermicompost, and 60% MM360 and 40% vermicompost to grow peppers (Capsicum annuum L.), tomatoes (Lycopersicon esculentum Mill.) and cabbages (Brassica oleracea L.), in pots. Groups of 10 pots containing young plants were distributed randomly in nylon mesh cages (40 cm x 40 cm x 40 cm). Groups of 10 pepper seedlings in a single cage were infested with either 100 aphids (Myzus persicae Sulz.) or 50 mealy bugs (Pseudococcus spp.) per cage. Similar groups of tomato seedlings were infested with 50 mealy bugs per cage. Groups of four cabbage seedlings in pots in cages were infested with 16 cabbage white caterpillars (Pieris brassicae L.). Populations of aphids and mealy bugs were counted after 20 days and the shoot dry weights of peppers, tomatoes and cabbages were measured at harvest. Numbers of cabbage white caterpillars and loss in shoot weights were measured after 15 days. The substitution rates of 20% and 40% vermicomposts suppressed populations of both aphids and mealy bugs on peppers, and mealy bugs on tomatoes, significantly. Substitutions with vermicomposts into MM360 decreased losses of dry weights of peppers, in response to both aphid and mealy bug infestations, decreased losses in shoot dry weights of tomatoes after mealy bug infestations significantly. There were significantly decreased losses in leaf areas of cabbage seedlings in response to the cabbage white caterpillar infestations. PMID:15683904

  3. Improving liquid bait programs for Argentine ant control: bait station density.

    PubMed

    Nelson, Erik H; Daane, Kent M

    2007-12-01

    Argentine ants, Linepithema humile (Mayr), have a positive effect on populations of mealybugs (Pseudococcus spp.) in California vineyards. Previous studies have shown reductions in both ant activity and mealybug numbers after liquid ant baits were deployed in vineyards at densities of 85-620 bait stations/ha. However, bait station densities may need to be <85 bait stations/ha before bait-based strategies for ant control are economically comparable to spray-based insecticide treatments-a condition that, if met, will encourage the commercial adoption of liquid baits for ant control. This research assessed the effectiveness of baits deployed at lower densities. Two field experiments were conducted in commercial vineyards. In experiment 1, baits were deployed at 54-225 bait stations/ha in 2005 and 2006. In experiment 2, baits were deployed at 34-205 bait stations/ha in 2006 only. In both experiments, ant activity and the density of mealybugs in grape fruit clusters at harvest time declined with increasing bait station density. In 2005 only, European fruit lecanium scale [Parthenolecanium corni (Bouché)] were also present in fruit clusters, and scale densities were negatively related to bait station density. The results indicate that the amount of ant and mealybug control achieved by an incremental increase in the number of bait stations per hectare is constant across a broad range of bait station densities. The results are discussed in the context of commercializing liquid ant baits to provide a more sustainable Argentine ant control strategy. PMID:18284776

  4. Oxygen enhances phosphine toxicity for postharvest pest control.

    PubMed

    Liu, Yong-Biao

    2011-10-01

    Phosphine fumigations under superatmospheric oxygen levels (oxygenated phosphine fumigations) were significantly more effective than the fumigations under the normal 20.9% atmospheric oxygen level against western flower thrips [Frankliniella occidentalis (Pergande)] adults and larvae, leafminer Liriomyza langei Frick pupae, grape mealybug [Pseudococcus maritimus (Ehrhorn)] eggs, and Indianmeal moth [Plodia interpunctella (Hübner)] eggs and pupae. In 5-h fumigations with 1,000 ppm phosphine at 5 degrees C, mortalities of western flower thrips increased significantly from 79.5 to 97.7% when oxygen was increased from 20.9 to 40% and reached 99.3% under 80% O2. Survivorships of leafminer pupae decreased significantly from 71.2% under 20.9% O2 to 16.2% under 40% O2 and reached 1.1% under 80% O2 in 24-h fumigations with 500 ppm phosphine at 5 degrees C. Complete control of leafminer pupae was achieved in 24-h fumigations with 1,000 ppm phosphine at 5 degrees C under 60% O2 or higher. Survivorships of grape mealybug eggs also decreased significantly in 48-h fumigations with 1,000 ppm phosphine at 2 degrees C under 60% O2 compared with the fumigations under 20.9% O2. Indian meal moth egg survivorships decreased significantly from 17.4 to 0.5% in responses to an oxygen level increase from 20.9 to 40% in 48-h fumigations with 1,000 ppm phosphine at 10 degrees C and reached 0.2% in fumigations under 80% O2. When the oxygen level was reduced from 20.9 to 15 and 10% in fumigations, survivorships of Indianmeal moth eggs increased significantly from 17.4 to 32.9 and 39.9%, respectively. Increased O2 levels also resulted in significantly lower survival rates of Indianmeal moth pupae in response to 24-h fumigations with 500 and 1,000 ppm phosphine at 10 degrees C and a complete control was achieved in the 1,000 ppm phosphine fumigations under 60% O2. Oxygenated phosphine fumigations have marked potential to improve insecticidal efficacy. Advantages and limitations of oxygenated