Science.gov

Sample records for aceria tosichella keifer

  1. Genetic characterization of North American populations of the wheat curl mite (Aceria tosichella) and dry bulb mite (Aceria tulipae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat curl mite, Aceria tosichella Keifer, transmits at least three harmful viruses, wheat streak mosaic virus (WSMV), high plains virus (HPV), and Triticum mosaic virus (TriMV) to wheat (Triticum aestivum L.) throughout the Great Plains. This virus complex is considered to be the most serious d...

  2. Thermal Niches of Two Invasive Genotypes of the Wheat Curl Mite Aceria tosichella: Congruence between Physiological and Geographical Distribution Data

    PubMed Central

    2016-01-01

    The wheat curl mite (WCM), Aceria tosichella Keifer, is a major pest of cereals worldwide. It is also a complex of well-defined genetic lineages with divergent physiological traits, which has not been accounted for in applied contexts. The aims of the study were to model the thermal niches of the two most pestiferous WCM lineages, designated MT-1 and MT-8, and to assess the extent to which temperature determines the distribution of these lineages. WCM population dynamics were modeled based on thermal niche data from March to November on the area of Poland (>311,000 km2). The most suitable regions for population development were predicted and compared to empirical field abundance data. Congruence between modeled parameters and field data for mite presence were observed for both WCM lineages although congruence between modeled thermal suitability and mite field abundance was observed only for MT-8. Thermal niche data for MT-1 and MT-8 provide biological insights and aid monitoring and management of WCM and the plant viruses it vectors. The presented models accurately estimate distributions of WCM and can be incorporated into management strategies for both current and predicted climate scenarios. PMID:27123590

  3. Colony establishment and maintenance of the eriophyid wheat curl mite Aceria tosichella for controlled transmission studies on a new virus-like pathogen.

    PubMed

    Skare, J M; Wijkamp, I; Rezende, J; Michels, G; Rush, C; Scholthof, K-B G; Scholthof, H B

    2003-03-01

    High plains disease (HPD) is of serious economic concern for wheat and corn production, but little is known about the virus-like causal agent. In the field, HPD is often associated with Wheat streak mosaic virus (WSMV) and both pathogens are transmitted by the same eriophyid wheat curl mite, Aceria tosichella Keifer. The objective of this study was to develop methods for establishing and maintaining HPD-transmitting wheat curl mite colonies for their use in studies on HPD. Towards this goal, mite colonies from a mixed infection source were separated into colonies either (i). not viruliferous; (ii). only transmitting WSMV; or (iii). only transmitting HPD. Maintenance of these colonies required strictly separated incubator facilities and adaptation of mite-suitable transfer techniques to permit frequent passages of mites to healthy plants. The established colonies provided reliable sources of infective material to study the progression of HPD and/or WSMV in plants using sensitive immuno-detection assays. In conclusion, we have developed reliable methods with a poorly studied arthropod vector to examine the biology and properties of a new virus-like disease. PMID:12565164

  4. [Can Euseius alatus DeLeon (Acari: Phytoseiidae) prey on Aceria guerreronis Keifer (Acari: Eriophyidae) in coconut palm?].

    PubMed

    Melo, José W da S; Domingos, Cleiton A; Gondim, Manoel G C; Moraes, Gilberto J de

    2009-01-01

    Mites of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae), and Tetranychus urticae Koch (Tetranychidae) + R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis in the field. PMID:19347108

  5. Status of Aceria guerreronis Keifer (Acari: Eriophyidae) as a pest of coconut in the state of Sao Paulo, southeastern Brazil.

    PubMed

    Oliveira, D C; de Moraes, G J; Dias, C T S

    2012-08-01

    The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of São Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in São Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development. PMID:23950068

  6. Winter wheat cultivars with temperature sensitive resistance to wheat streak mosaic virus do not recover from early season infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV), Triticum mosaic virus, and Wheat mosaic virus, all vectored by the wheat curl mite Aceria tosichella Keifer, frequently cause devastating losses to winter wheat production throughout the central and western Great Plains. Resistant 'Mace' and 'RonL' are commercially ...

  7. Economic impact of wheat streak mosaic virus in the Texas High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV), vectored by the wheat curl mite Aceria tosichella Keifer, is a major limiting factor in wheat production in the Texas Panhandle. It is the most frequently encountered virus in the region, affecting both shoot and root biomass, and consequently it can drastically red...

  8. Identification of the Wheat Curl Mite as the Vector of Triticum Mosaic Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Triticum mosaic virus (TriMV) is a newly discovered virus found infecting wheat (Triticum aestivum L.) in Kansas. This study was conducted to determine if the wheat curl mite (WCM, Aceria tosichella Keifer) and the bird cherry oat aphid (Rhopalosiphum padi L. ) could transmit TriMV. Using diffe...

  9. Effects of single and double infections of winter wheat by Triticum mosaic virus and Wheat streak mosaic virus on yield determinants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Triticum mosaic virus (TriMV) is a recently discovered virus infecting wheat (Triticum aestivum L.) in the Great Plains region of the United States. It is transmitted by wheat curl mites (Aceria tosichella Keifer) which also transmit Wheat streak mosaic virus (WSMV) and Wheat mosaic virus. In a gree...

  10. Amino acid substitutions of cysteine residues near the amino terminus of Wheat streak mosaic virus HC-Pro abolishes virus transmission by the wheat curl mite

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The amino-terminal half of HC-Pro of Wheat streak mosaic virus (WSMV) is required for semi-persistent transmission by the wheat curl mite (Aceria tosichella Keifer). The amino-proximal region of WSMV HC-Pro is cysteine-rich with a zinc finger-like motif. Amino acid substitutions were made in this re...

  11. Substitution of conserved cysteine residues in Wheat streak mosaic virus HC-Pro abolishes virus transmission by the wheat curl mite

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Substitutions in the amino-terminal region of Wheat streak mosaic virus (WSMV) HC-Pro were evaluated for effects on transmission by the wheat curl mite (Aceria tosichella Keifer). Alanine substitution at cysteine residues 16, 46 and 49 abolished vector transmission. Although alanine substitution a...

  12. Host finding behaviour of the coconut mite Aceria guerreronis.

    PubMed

    Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

    2014-12-01

    For the coconut mite, Aceria guerreronis Keifer, its host plant, the coconut palm, is not merely a source of food, but more generally a habitat to live in for several generations. For these minute organisms, finding a new plant is difficult and risky, especially because their main mode of dispersal is passive drifting with the wind and because they are highly specialized on their host plant. Consequently, the probability of landing on a suitable host is very low, let alone to land in their specific microhabitat within the host. How coconut mites manage to find their microhabitat within a host plant is still underexplored. We tested the hypothesis that they use volatile chemical information emanating from the plant to find a specific site within their host plants and/or use non-volatile plant chemicals to stay at a profitable site on the plant. This was investigated in a Y-tube olfactometer (i.e. under conditions of a directed wind flow) and on cross-shaped arenas (i.e. under conditions of turbulent air) that either allowed contact with odour sources or not. The mites had to choose between odours from specific parts (leaflet, spikelet or fruit) of a non-infested coconut plant and clean air as the alternative. In the olfactometer experiments, no mites were found to reach the upwind end of the Y-tube: <5 % of the mites were able to pass the bifurcation of the "Y". On the cross-shaped arenas, however, a large number of coconut mites was found only when the arm of the arena contained discs of fruit epidermis and contact with these discs was allowed. The results suggest that coconut mites on palm trees are not attracted to specific sites on the plant by volatile plant chemicals, but that they arrested once they contact the substrate of specific sites. Possibly, they perceive non-volatile chemicals, but these remain to be identified. PMID:25033768

  13. Nine eriophyoid mite species from Iran (Acari, Eriophyidae).

    PubMed

    Xue, Xiao-Feng; Sadeghi, Hussein; Hong, Xiao-Yue; Sinaie, Samira

    2011-01-01

    Nine eriophyoid mites, including two new species and five new records, from Iran are described and illustrated. They are Aceria acroptiloni Shevchenko & Kacalev, 1974, rec. n. on Rhaponticum repens (L.) Hidalgo (Asteraceae); Aceria anthocoptes (Nalepa, 1892), rec. n. on Cirsium arvense (L.) Scop. (Asteraceae); Aceria lactucae (Canestrini, 1893), rec. n. on Lactuca virosa L. (Asteraceae); Aceria pulicarissp. n. on Pulicaria gnaphalodes (Vent.) Boiss. (Asteraceae); Aceria tosichella Keifer, 1969 on Setaria viridis (L.) Beauv. (Poaceae); Eriophyes rotundae Mohanasundaram, 1983 on Cyperus rotundus L. (Cyperaceae); Aculops maroccensis Keifer, 1972, rec. n. on Mentha piperita L. (Lamiaceae); Aculus medicagersp. n. on Medicago sativa L. (Leguminosae); Tetra lycopersici Xue & Hong, 2005, rec. n. on Solanum nigrum L. (Solanaceae). PMID:22144865

  14. Acaricide-impaired functional predation response of the phytoseiid mite Neoseiulus baraki to the coconut mite Aceria guerreronis.

    PubMed

    Lima, D B; Melo, J W S; Gondim, M G C; Guedes, R N C; Oliveira, J E M; Pallini, A

    2015-07-01

    Acaricides may interfere with a myriad of interactions among arthropods, particularly predator-prey interactions. The coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae), and its phytoseiid predator, Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae), provide an opportunity to explore such interference because the former is a key coconut pest species that requires both predation and acaricide application for its management. The objective of the present study was to assess the effect of the acaricides abamectin, azadirachtin and fenpyroximate on the functional response of N. baraki to A. guerreronis densities. The following prey densities were tested: 5, 10, 20, 40 and 80 preys. The type of functional response and prey handling time (Th) were not altered by the acaricides. However, the attack rate (a') was modified by abamectin and fenpyroximate, and the consumption peak was reduced by abamectin. All of the acaricides allowed for the maintenance of the predator in the field, but exposure to abamectin and fenpyroximate compromised prey consumption. PMID:25847106

  15. Occurrence and seasonal prevalence of the coconut mite, Aceria guerreronis (Eriophyidae), and associated arthropods in Oman.

    PubMed

    Al-Shanfari, Abdulaziz; Hountondji, Fabien C C; Al-Zawamri, Hamid; Rawas, Hassan; Al-Mashiki, Yussef; de Moraes, Gilberto J; Moore, Dave; Gowen, Simon R

    2013-06-01

    The coconut palm is an important crop in the sub arid coastal plain of Dhofar, Oman, for the high demand for its nut water and its use as ornamental plant. Damage of coconut fruits by the eriophyid mite Aceria guerreronis Keifer was first reported in that region in the late 1980s, but background information about the ecology of the pest in Oman was missing. Four surveys were conducted in different seasons from 2008 to 2009, to assess the distribution and prevalence of the coconut mite and its damage as well as the presence of natural enemies. Infestation by the coconut mite was conspicuous on most (99.7 %) palm trees, with 82.5 % damaged fruits. The average (± SE) density of coconut mites per fruit was 750 ± 56; this level of infestation led to the incidence of over 25 % of surface damage on more than half of the fruits. The mite appeared more abundant at the end of the cold season through the summer. No significant differences were observed between infestation levels on local varieties, hybrids and on dwarf varieties. Neoseiulus paspalivorus (De Leon), Cydnoseius negevi (Swirski & Amitai) and Amblyseius largoensis (Muma) were the predatory mites found under the bracts of over 30 % of the coconut fruits and on 68 % of the coconut trees. Considering all sampling dates and all varieties together, average (± SE) phytoseiid density was 1.4 ± 1.19 per fruit. Other mites found in the same habitat as A. guerreronis included the tarsonemids Steneotarsonemus furcatus De Leon and Nasutitarsonemus omani Lofego & Moraes. The pathogenic fungus Hirsutella thompsonii Fisher was rarely found infecting the coconut mite in Dhofar. Other fungal pathogens, namely Cordyceps sp. and Simplicillium sp., were more prevalent. PMID:23435864

  16. Evidence of Amblyseius largoensis and Euseius alatus as biological control agent of Aceria guerreronis.

    PubMed

    Melo, J W S; Lima, D B; Staudacher, H; Silva, F R; Gondim, M G C; Sabelis, M W

    2015-11-01

    Amblyseius largoensis (Muma) (Acari: Phytoseiidae) and Euseius alatus De Leon (Acari: Phytoseiidae) are predatory mites that are mostly found on leaves and on the exposed fruit surface of coconut plants. Their morphology hampers the access to the microhabitat occupied by Aceria guerreronis Keifer (Acari: Eriophyidae), the most important pest of coconut fruits throughout the world. However, it was suggested that they can prey on A. guerreronis under natural conditions when this pest leaves its refuge to disperse. Since the trophic interactions between A. largoensis or E. alatus and A. guerreronis are unknown, we compare the frequencies of occurrence of A. largoensis and E. alatus under the bracts of coconut fruits and on coconut leaflets. In addition, because phytoseiids feed by liquid ingestion, we used molecular analysis to confirm the potential role of A. largoensis or E. alatus as predators of A. guerreronis and to assess how fast the A. guerreronis DNA fragment is degradated in the A. largoensis digestive tract. Our study demonstrated that E. alatus was only present on coconut leaflets whereas A. largoensis was found mostly on leaflets and, to a much lesser extent, under the bracts of coconuts. Species-specific ITS primers designed for A. guerreronis were shown to have a high degree of specificity for A. guerreronis DNA and did not produce any PCR product from DNA templates of the other insects and mites associated with the coconut agroecosystem. Based on molecular analysis, we confirmed that the predatory mites, A. largoensis and E. alatus, had preyed on the coconut mite in the field. Overall the predatory mites collected in the field exhibited low levels of predation (26.7% of A. largoensis and 8.9% of E. alatus tested positive for A. guerreronis DNA). The fragment of A. guerreronis DNA remained intact for a very short time (no more than 6 h after feeding) in the digestive tract of A. largoensis. PMID:26255279

  17. Olfactory response of predatory mites to vegetative and reproductive parts of coconut palm infested by Aceria guerreronis.

    PubMed

    Melo, José Wagner S; Lima, Debora B; Pallini, Angelo; Oliveira, José Eudes M; Gondim, Manoel G C

    2011-10-01

    The phytophagous mite Aceria guerreronis Keifer is an important pest of coconut worldwide. A promising method of control for this pest is the use of predatory mites. Neoseiulus baraki (Athias-Henriot) and Proctolaelaps bickleyi Bram are predatory mites found in association with A. guerreronis in the field. To understand how these predators respond to olfactory cues from A. guerreronis and its host plant, the foraging behavior of the predatory mites was investigated in a Y-tube olfactometer and on T-shaped arenas. The predators were subjected to choose in an olfactometer: (1) isolated parts (leaflet, spikelet or fruit) of infested coconut plant or clean air stream; (2) isolated parts of non-infested or infested coconut plant; and (3) two different plant parts previously shown to be attractive. Using T-shaped arenas the predators were offered all possible binary combinations of discs of coconut fruit epidermis infested with A. guerreronis, non-infested discs or coconut pollen. The results showed that both predators were preferred (the volatile cues from) the infested plant parts over clean air. When subjected to odours from different infested or non-infested plant parts, predators preferred the infested parts. Among the infested plant parts, the spikelets induced the greatest attraction to predators. On the arenas, both predators preferred discs of coconut fruits infested with A. guerreronis over every other alternative. The results show that both predators are able to locate A. guerreronis by olfactory stimuli. Foraging strategies and implications for biological control are discussed. PMID:21499777

  18. Exploration of the acarine fauna on coconut palm in Brazil with emphasis on Aceria guerreronis (Acari: Eriophyidae) and its natural enemies.

    PubMed

    Lawson-Balagbo, L M; Gondim, M G C; de Moraes, G J; Hanna, R; Schausberger, P

    2008-02-01

    Coconut is an important crop in tropical and subtropical regions. Among the mites that infest coconut palms, Aceria guerreronis Keifer is economically the most important. We conducted surveys throughout the coconut growing areas of Brazil. Samples were taken from attached coconuts, leaflets, fallen coconuts and inflorescences of coconut palms in 112 localities aiming to determine the occurrence and the distribution of phytophagous mites, particularly A. guerreronis, and associated natural enemies. Aceria guerreronis was the most abundant phytophagous mite followed by Steneotarsonemus concavuscutum Lofego & Gondim Jr. and Steneotarsonemus furcatus De Leon (Tarsonemidae). Infestation by A. guerreronis was recorded in 87% of the visited localities. About 81% of all predatory mites belonged to the family Phytoseiidae, mainly represented by Neoseiulus paspalivorus De Leon, Neoseiulus baraki Athias-Henriot and Amblyseius largoensis Muma; 12% were Ascidae, mainly Proctolaelaps bickleyi Bram, Proctolaelaps sp nov and Lasioseius subterraneus Chant. Neoseiulus paspalivorus and N. baraki were the most abundant predators on attached coconuts. Ascidae were predominant on fallen coconuts, while A. largoensis was predominant on leaflets; no mites were found on branches of inflorescences. Leaflets harboured higher mite diversity than the attached coconuts. Mite diversity was the highest in the state Pará and on palms surrounded by seasonal forests and Amazonian rain-forests. Neoseiulus paspalivorus, N. baraki and P. bickleyi were identified as the most promising predators of A. guerreronis. Analyses of the influence of climatic factors revealed that dry ambient conditions favour the establishment of A. guerreronis. Neoseiulus paspalivorus and N. baraki have differing climatic requirements; the former being more abundant in warm and dry areas, the latter prevailing in moderately tempered and humid areas. We discuss the significance of our findings for natural and biological

  19. Additional information regarding host specificity of Aceria salsolae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The petition submitted to USDA-APHIS Technical Advisory Group on Dec. 16, 2004 (No. 04-06) indicated that the eriophyid mite, Aceria salsolae, will infest all the weedy Salsola species (Russian thistle; tumbleweeds) in the Salsola kali section (S. tragus, S. collina, S. paulsenii, S. australis (=typ...

  20. The invasive coconut mite Aceria guerreronis (Acari: Eriophyidae): origin and invasion sources inferred from mitochondrial (16S) and nuclear (ITS) sequences.

    PubMed

    Navia, D; de Moraes, G J; Roderick, G; Navajas, M

    2005-12-01

    Over the past 30 years the coconut mite Aceria guerreronis Keifer has emerged as one of the most important pests of coconut and has recently spread to most coconut production areas worldwide. The mite has not been recorded in the Indo-Pacific region, the area of origin of coconut, suggesting that it has infested coconut only recently. To investigate the geographical origin, ancestral host associations, and colonization history of the mite, DNA sequence data from two mitochondrial and one nuclear region were obtained from samples of 29 populations from the Americas, Africa and the Indo-ocean region. Mitochondrial DNA 16S ribosomal sequences were most diverse in Brazil, which contained six of a total of seven haplotypes. A single haplotype was shared by non-American mites. Patterns of nuclear ribosomal internal transcribed spacer (ITS) variation were similar, again with the highest nucleotide diversity found in Brazil. These results suggest an American origin of the mite and lend evidence to a previous hypothesis that the original host of the mite is a non-coconut palm. In contrast to the diversity in the Americas, all samples from Africa and Asia were identical or very similar, consistent with the hypothesis that the mite invaded these regions recently from a common source. Although the invasion routes of this mite are still only partially reconstructed, the study rules out coconut as the ancestral host of A. guerreronis, thus prompting a reassessment of efforts using quarantine and biological control to check the spread of the pest. PMID:16336700

  1. Interaction of Aceria mangiferae with Fusarium mangiferae, the causal agent of mango malformation disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study examines the role of the mango bud mite, Aceria mangiferae, in carrying Fusarium mangiferae’s conidia, vectoring them into the penetration sites and assisting fungal penetration and dissemination. Conidia that were exposed to a green fluorescent protein (gfp)-marked isolate of F. mangifer...

  2. New records for Aceria anthocopes (Acari: Eriophyidae) occurring on Canada thistle in Colorado, Nebraska and Wyoming

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-two Canada thistle infestations in eastern Colorado and Wyoming and western Nebraska were surveyed in 2004 for the eriophyid mite Aceria anthocoptes (Nal.). Mites were abundant at 41% of the sites, present in lesser numbers at 53% of the sites, and no mites were found at 6% of the sites. In 2...

  3. Laboratory and field experimental evaluation of host plant specificity of Aceria solstitialis, a prospective biological control agent of yellow starthistle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow starthistle (Centaurea solstitialis) is an invasive annual weed in the western USA that is native to the Mediterranean Region and is a target for classical biological control. Aceria solstitialis is an eriophyid mite that has been found exclusively in association with yellow starthistle in I...

  4. A new species, of Aceria neopaederiae (Acari: Eriophyidae), infesting Paederia foetida L. (Rubiaceae) in Thailand, Hong Kong and Singapore

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aceria paederiae (Nalepa) infesting leaves of Paederia foetida L. (Family Rubiaceae) in Thailand, Hong Kong and Singapore is reported for the first time. The mite induces small, round galls on both leaf surfaces. The complete descriptions of both males and females, including line drawings and SEM ...

  5. Field garden experiments to assess the host specificity of Aceria solstitialis (Acari: Eriophyoidea), potential biocontrol agent for Centaurea solstitialis (Asteraceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Centaurea solstitialis (yellow starthistle) is an annual noxious weed that currently infests millions of acres of rangelands, non-cultivated and natural areas in the Western USA. It displaces native plant communities reducing plant diversity and forage production for livestock and wildlife. Aceria s...

  6. Field assessment of host plant specificity and potential effectiveness of a prospective biological control agent, Aceria salsolae, of Russian thistle, Salsola tragus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The eriophyid mite, Aceria salsolae attacks several species of invasive alien tumbleweeds, including Salsola tragus, S. collina, S. paulsenii and S. australis, in North America. Previous laboratory experiments to determine host specificity of the mite indicated that it could sometimes persist and m...

  7. Agistemus aimogastaensis sp. n. (Acari, Actinedida, Stigmaeidae), a recently discovered predator of eriophyid mites Aceria oleae and Oxycenus maxwelli, in olive orchards in Argentina

    PubMed Central

    Leiva, Sergio; Fernandez, Nestor; Theron, Pieter; Rollard, Christine

    2013-01-01

    Abstract A new species, Agistemus aimogastaensis, is described with the aid of optical and Scanning Electron Microscopy. This mite is an important predator of two eriophyid mites (Aceria oleae and Oxycenus maxwelli) in olive orchards (Olea europaea, variety Arauco) in La Rioja Province. The problems related to eriophyids in olive orchards in Argentina are highlighted and photos of the damage on leaves and fruit are included. PMID:23825448

  8. Planting Date and Variety Selection for Management of Viruses Transmitted by the Wheat Curl Mite (Acari: Eriophyidae).

    PubMed

    McMechan, Anthony J; Hein, Gary L

    2016-02-01

    Wheat is an important food grain worldwide, and it is the primary dryland crop in the western Great Plains. A complex of three viruses (Wheat streak mosaic, Wheat mosaic, and Triticum mosaic viruses) is a common cause of loss in winter wheat production in the Great Plains. All these viruses are transmitted by the wheat curl mite (Aceria tosichella Keifer). Once these viruses are established, there are no curative actions; therefore, prevention is the key to successful management. A study was designed to evaluate preventative management tactics (planting date, resistant varieties) for reducing the impact from this virus complex. The main plot treatments were three planting dates, and split-plot treatments were three wheat varieties. Varieties were planted at three different times during the fall to simulate early, recommended, and late planting dates. The varieties evaluated in this study were Mace (virus resistant), Millennium (mild tolerance), and Tomahawk (susceptible). Measurements of virus symptomology and yield were used to determine virus impact. Results consistently showed that the resistant Mace yielded more than Millennium or Tomahawk under virus pressure. In some years, delayed planting improved the yields for all varieties, regardless of their background; however, under the most severe virus pressure the combination of both management strategies was not sufficient to provide practical control of this complex. These results illustrate the importance of using a combination of management tactics for this complex, but also reinforce the importance for producers to use additional management strategies (e.g., control preharvest volunteer wheat) to manage this complex. PMID:26516091

  9. Wheat curl mite and dry bulb mite: untangling a taxonomic conundrum through a multidisciplinary approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The taxonomy of two economically important eriophyoid species, Aceria tosichella (wheat curl mite, WCM) and A. tulipae (dry bulb mite, DBM), was confounded in the world literature until the late 20th century due to their morphological similarity and ambiguous data from plant-transfer and virus-trans...

  10. Global spread of wheat curl mite by the most polyphagous and pestiferous lineages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat curl mite (WCM), Aceria tosichella, is an important pest of wheat and other cereal crops that transmits wheat streak mosaic virus and several other plant viruses. WCM has long been considered a single polyphagous species, but recent studies in Poland revealed a complex of genetically disti...

  11. Incidence of Wheat streak mosaic virus, Triticum mosaic virus, and Wheat mosaic virus in wheat curl mites recovered from maturing winter wheat spikes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat curl mites (WCM; Aceria tosichella) transmit Wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV), and Wheat mosaic virus (WMoV) to wheat (Triticum aestivum L.) in the Great Plains region of the United States. These viruses can be detected in single, double, or triple combinations i...

  12. The Effect of Temperature, Relative Humidity, and Virus Infection Status on off-host Survival of the Wheat Curl Mite (Acari: Eriophyidae).

    PubMed

    Wosula, E N; McMechan, A J; Hein, G L

    2015-08-01

    The wheat curl mite, Aceria tosichella Keifer, is an eriophyid pest of wheat, although its primary economic impact on wheat is due to the transmission of Wheat streak mosaic (WSMV), Wheat mosaic (also known as High Plains virus), and Triticum mosaic (TriMV) viruses. These viruses cause significant annual losses in winter wheat production throughout the western Great Plains. Temperature and humidity are factors that often influence arthropod survival, especially during dispersal from their hosts, yet the impact of these two factors on off-host survival has not been documented for wheat curl mite. Pathogen-infected host plants often influence the biology and behavior of vectors, yet it is not known if virus-infected wheat affects off-host survival of wheat curl mite. The objectives of this study were to 1) determine if temperature, relative humidity, and mite genotype impact off-host survival of wheat curl mite and 2) determine the effect of WSMV- and TriMV-infected host plants on off-host survival of wheat curl mite. Temperature and relative humidity significantly affected off-host survival of wheat curl mite. Length of survival decreased with increasing temperature (106.2 h at 10°C and 17.0 h at 30°C) and decreasing relative humidity (78.1 h at 95 and 21.3 h at 2%). Mites from TriMV-infected host plants had ∼20% reduction in survival at 20°C compared with those from WSMV-infected plants. The duration of off-host survival of wheat curl mite is influenced by environmental conditions. Management strategies that target a break in host presence will greatly reduce mite densities and virus spread and need to account for these limits. PMID:26470294

  13. Intraguild predation and cannibalism between the predatory mites Neoseiulus neobaraki and N. paspalivorus, natural enemies of the coconut mite Aceria guerreronis.

    PubMed

    Negloh, Koffi; Hanna, Rachid; Schausberger, Peter

    2012-11-01

    Neoseiulus neobaraki and N. paspalivorus are amongst the most common phytoseiid predators of coconut mite, Aceria guerreronis, found in the spatial niche beneath coconut fruit bracts. Both predators may occur on the same coconut palms in Benin and Tanzania and are therefore likely to interact with each other. Here, we assessed cannibalism and intraguild predation (IGP) of the two predators in the absence and presence of their primary prey A. guerreronis. In the absence of the shared extraguild prey, A. guerreronis, N. neobaraki killed 19 larvae of N. paspalivorus per day and produced 0.36 eggs/female/day, while the latter species killed only 7 larvae of the former and produced 0.35 eggs/female/day. Presence of A. guerreronis only slightly decreased IGP by N. neobaraki but strongly decreased IGP by N. paspalivorus, which consumed 4-7 times less IG prey than N. neobaraki. Resulting predator offspring to IG prey ratios were, however, 4-5 times higher in N. paspalivorus than N. neobaraki. Overall, provision of A. guerreronis increased oviposition in both species. In the cannibalism tests, in the absence of A. guerreronis, N. neobaraki and N. paspalivorus consumed 1.8 and 1.2 conspecific larvae and produced almost no eggs. In the presence of abundant herbivorous prey, cannibalism dramatically decreased but oviposition increased in both N. neobaraki and N. paspalivorus. In summary, we conclude that (1) N. neobaraki is a much stronger intraguild predator than N. paspalivorus, (2) cannibalism is very limited in both species, and (3) both IGP and cannibalism are reduced in the presence of the common herbivorous prey with the exception of IGP by N. neobaraki, which remained at high levels despite presence of herbivorous prey. We discuss the implications of cannibalism and IGP on the population dynamics of A. guerreronis and the predators in view of their geographic and within-palm distribution patterns. PMID:22669279

  14. Plant structural changes due to herbivory: Do changes in Aceria-infested coconut fruits allow predatory mites to move under the perianth?

    PubMed Central

    Aratchige, Nayanie S.; Lesna, Izabela

    2007-01-01

    Being minute in size, eriophyoid mites can reach places that are small enough to be inaccessible to their predators. The coconut mite, Aceria guerreronis, is a typical example; it finds partial refuge under the perianth of the coconut fruit. However, some predators can move under the perianth of the coconut fruits and attack the coconut mite. In Sri Lanka, the phytoseiid mite Neoseiulus baraki, is the most common predatory mite found in association with the coconut mite. The cross-diameter of this predatory mite is c. 3 times larger than that of the coconut mite. Nevertheless, taking this predator’s flat body and elongated idiosoma into account, it is—relative to many other phytoseiid mites—better able to reach the narrow space under the perianth of infested coconut fruits. On uninfested coconut fruits, however, they are hardly ever observed under the perianth. Prompted by earlier work on the accessibility of tulip bulbs to another eriophyoid mite and its predators, we hypothesized that the structure of the coconut fruit perianth is changed in response to damage by eriophyoid mites and as a result predatory mites are better able to enter under the perianth of infested coconut fruits. This was tested in an experiment where we measured the gap between the rim of the perianth and the coconut fruit surface in three cultivars (‘Sri Lanka Tall’, ‘Sri Lanka Dwarf Green’ and ‘Sri Lanka Dwarf Green × Sri Lanka Tall’ hybrid) that are cultivated extensively in Sri Lanka. It was found that the perianth-fruit gap in uninfested coconut fruits was significantly different between cultivars: the cultivar ‘Sri Lanka Dwarf Green’ with its smaller and more elongated coconut fruits had a larger perianth-fruit gap. In the uninfested coconut fruits this gap was large enough for the coconut mite to creep under the perianth, yet too small for its predator N. baraki. However, when the coconut fruits were infested by coconut mites, the perianth-rim-fruit gap was not

  15. Eriophyoid mites (Acari: Trombidiformes: Eriophyoidea) of Rosales trees in Iran: two new species and three new records.

    PubMed

    Lotfollahi, Parisa; Irani-Nejad, Karim Haddad; De Lillo, Enrico

    2014-01-01

    This paper describes two new species of Eriophyoidea associated with trees belonging to the order Rosales in the south-western portion of East Azerbaijan province, Iran, collected during a survey in 2011: Aceria lobolinguae n. sp. on Elaeagnus angustifolia L. (Elaeagnaceae) and Rhinophytoptus nemalobos n. sp. on Prunus domestica L. (Rosaceae). Additionally, Phyllocoptes abaenus Keifer on Prunus armeniaca L. (Rosaceae), Aculus fockeui (Nalepa & Trouessart) on Prunus amygdalus Stokes and Malus domestica Borkh. (Rosaceae), and Aceria mori (Keifer) on Morus alba L. (Moraceae) were collected and are new records for the mite fauna of Iran. New locality records and host plant data are provided for Eriophyes similis (Nalepa), Eriophyes pyri (Pagenstecher) and Calepitrimerus baileyi (Keifer) which are eriophyoid species previously known from Iran.  PMID:25283393

  16. Remote sensing to detect the movement of wheat curl mites through the spatial spread of virus symptoms, and identification of thrips as predators of wheat curl mites

    NASA Astrophysics Data System (ADS)

    Stilwell, Abby R.

    The wheat curl mite (WCM), Aceria tosichella Keifer, transmits three viruses to winter wheat: wheat streak mosaic virus, High Plains virus, and Triticum mosaic virus. This virus complex causes yellowing of the foliage and stunting of plants. WCMs disperse by wind, and an increased understanding of mite movement and subsequent virus spread is necessary in determining the risk of serious virus infections in winter wheat. These risk parameters will help growers make better decisions regarding WCM management. The objectives of this study were to evaluate the capabilities of remote sensing to identify virus infected plants and to establish the potential of using remote sensing to track virus spread and consequently, mite movement. Although the WCM is small and very hard to track, the viruses it vectors produce symptoms that can be detected with remote sensing. Field plots of simulated volunteer wheat were established between 2006 and 2009, infested with WCMs, and spread mites and virus into adjacent winter wheat. The virus gradients created by WCM movement allowed for the measurement of mite movement potential with both proximal and aerial remote sensing instruments. The ability to detect WCM-vectored viruses with remote sensing was investigated by comparing vegetation indices calculated from proximal remote sensing data to ground truth data obtained in the field. Of the ten vegetation indices tested, the red edge position (REP) index had the best relationship with ground truth data. The spatial spread of virus from WCM source plots was modeled with cokriging. Virus symptoms predicted by cokriging occurred in an oval pattern displaced to the southeast. Data from the spatial spread in small plots of this study were used to estimate the potential sphere of influence for volunteer wheat fields. The impact of thrips on WCM populations was investigated by a series of greenhouse, field, and observational studies. WCM populations in winter wheat increased more slowly when

  17. A New Species of Aculops Keifer (Acari: Prostigmata: Eriophyidae) on Dipsacus laciniatus L. (Dipsacaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Investigations have been conducted in Europe in the last decade in order to find potential agents for biological control of invasive teasels in North America. During surveys conducted in Serbia in May 2007, the new eriophyid mite species Aculops dipsaci n. sp. (Acari: Prostigmata: Eriophyidae) was ...

  18. Sequence diversity of wheat mosaic virus isolates.

    PubMed

    Stewart, Lucy R

    2016-02-01

    Wheat mosaic virus (WMoV), transmitted by eriophyid wheat curl mites (Aceria tosichella) is the causal agent of High Plains disease in wheat and maize. WMoV and other members of the genus Emaravirus evaded thorough molecular characterization for many years due to the experimental challenges of mite transmission and manipulating multisegmented negative sense RNA genomes. Recently, the complete genome sequence of a Nebraska isolate of WMoV revealed eight segments, plus a variant sequence of the nucleocapsid protein-encoding segment. Here, near-complete and partial consensus sequences of five more WMoV isolates are reported and compared to the Nebraska isolate: an Ohio maize isolate (GG1), a Kansas barley isolate (KS7), and three Ohio wheat isolates (H1, K1, W1). Results show two distinct groups of WMoV isolates: Ohio wheat isolate RNA segments had 84% or lower nucleotide sequence identity to the NE isolate, whereas GG1 and KS7 had 98% or higher nucleotide sequence identity to the NE isolate. Knowledge of the sequence variability of WMoV isolates is a step toward understanding virus biology, and potentially explaining observed biological variation. PMID:26590326

  19. Survival and behavioural response to acaricides of the coconut mite predator Neoseiulus baraki.

    PubMed

    Lima, Debora B; Melo, José W S; Guedes, Raul N C; Siqueira, Herbert A A; Pallini, Angelo; Gondim, Manoel G C

    2013-07-01

    The coconut mite, Aceria guerreronis Keifer, is a major pest of coconut palm in the world. The control of this pest species is done through acaricide applications at short time intervals. However, the predators of this pest may also be affected by acaricides. Among the predators of A. guerreronis, Neoseiulus baraki (Athias-Henriot) has potential for biological control. The objective of this study was to assess the effect of acaricides on the survival and behavior of N. baraki. The survivorship of N. baraki was recorded in surface-impregnated arenas. Choice and no-choice behavioral bioassays were carried out using a video tracking system to assess the walking behavior of the predator under acaricide exposure. Although all acaricides negatively affected the survival of N. baraki, chlorfenapyr and azadirachtin caused lower effect than the other acaricides. No significant differences in walking behavior were observed under exposure to fenpyroximate, chlorfenapyr and chlorpyrifos on fully-contaminated arenas. Azadirachtin and chlorpyrifos caused repellence. Irritability was observed for all acaricides, except for abamectin. Chlorfenapyr was the most suitable product for managing the coconut mite because of its low effect on survival and behavior of N. baraki. PMID:23224672

  20. Bioinsecticide-Predator Interactions: Azadirachtin Behavioral and Reproductive Impairment of the Coconut Mite Predator Neoseiulus baraki

    PubMed Central

    Lima, Debora B.; Melo, José Wagner S.; Guedes, Nelsa Maria P.; Gontijo, Lessando M.; Guedes, Raul Narciso C.; Gondim, Manoel Guedes C.

    2015-01-01

    Synthetic pesticide use has been the dominant form of pest control since the 1940s. However, biopesticides are emerging as sustainable pest control alternatives, with prevailing use in organic agricultural production systems. Foremost among botanical biopesticides is the limonoid azadirachtin, whose perceived environmental safety has come under debate and scrutiny in recent years. Coconut production, particularly organic coconut production, is one of the agricultural systems in which azadirachtin is used as a primary method of pest control for the management of the invasive coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae). The management of this mite species also greatly benefits from predation by Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae). Here, we assessed the potential behavioral impacts of azadirachtin on the coconut mite predator, N. baraki. We explored the effects of this biopesticide on overall predator activity, female searching time, and mating behavior and fecundity. Azadirachtin impairs the overall activity of the predator, reducing it to nearly half; however, female searching was not affected. In contrast, mating behavior was compromised by azadirachtin exposure particularly when male predators were exposed to the biopesticide. Consequently, predator fecundity was also compromised by azadirachtin, furthering doubts about its environmental safety and selectivity towards biological control agents. PMID:25679393

  1. Estimated crop loss due to coconut mite and financial analysis of controlling the pest using the acaricide abamectin.

    PubMed

    Rezende, Daniela; Melo, José W S; Oliveira, José E M; Gondim, Manoel G C

    2016-07-01

    Reducing the losses caused by Aceria guerreronis Keifer has been an arduous task for farmers. However, there are no detailed studies on losses that simultaneously analyse correlated parameters, and very few studies that address the economic viability of chemical control, the main strategy for managing this pest. In this study the objectives were (1) to estimate the crop loss due to coconut mite and (2) to perform a financial analysis of acaricide application to control the pest. For this, the following parameters were evaluated: number and weight of fruits, liquid albumen volume, and market destination of plants with and without monthly abamectin spraying (three harvests). The costs involved in the chemical control of A. guerreronis were also quantified. Higher A. guerreronis incidence on plants resulted in a 60 % decrease in the mean number of fruits harvested per bunch and a 28 % decrease in liquid albumen volume. Mean fruit weight remained unaffected. The market destination of the harvested fruit was also affected by higher A. guerreronis incidence. Untreated plants, with higher A. guerreronis infestation intensity, produced a lower proportion of fruit intended for fresh market and higher proportions of non-marketable fruit and fruit intended for industrial processing. Despite the costs involved in controlling A. guerreronis, the difference between the profit from the treated site and the untreated site was 18,123.50 Brazilian Real; this value represents 69.1 % higher profit at the treated site. PMID:27059867

  2. A new species of Leipothrix Keifer, 1966 (Acari: Eriophyidae) on Dipsacus spp. in Europe and reassignment of two Epitrimerus spp. (Acari: Eriophyidae) to the genus Leipothrix

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new species of eriophyid mite, Leipothrix dipsacivagus n. sp., collected from Dipsacus laciniatus L. (Dipsacaceae) and D. fullonum L. in Serbia and Montenegro, Bulgaria, and France, is described and illustrated. Differential diagnosis is provided in comparison with Leipothrix knautiae (Liro) n. co...

  3. Limits to ambulatory displacement of coconut mites in absence and presence of food-related cues.

    PubMed

    Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

    2014-04-01

    Ambulatory movement of plant-feeding mites sets limits to the distances they can cover to reach a new food source. In absence of food-related cues these limits are determined by survival, walking activity, walking path tortuosity and walking speed, whereas in presence of food the limits are also determined by the ability to orient and direct the path towards the food source location. For eriophyoid mites such limits are even more severe because they are among the smallest mites on earth, because they have only two pairs of legs and because they are very sensitive to desiccation. In this article we test how coconut mites (Aceria guerreronis Keifer) are constrained in their effective displacement by their ability to survive in absence of food (meristematic tissue under the coconut perianth) and by their ability to walk and orient in absence or presence of food-related cues. We found that the mean survival time decreased with increasing temperature and decreasing humidity. Under climatic conditions representative for the Tropics (27 °C and 75 % relative humidity) coconut mites survived on average for 11 h and covered 0.4 m, representing the effective linear displacement away from the origin. Within a period of 5 h, coconut mites collected from old fruits outside the perianth moved further away from the origin than mites collected under the perianth of young fruits. However, in the presence of food-related cues coconut mites traveled over 30 % larger distances than in absence of these cues. These results show that ambulatory movement of eriophyoid mites may well bring them to other coconuts within the same bunch and perhaps also to other bunches on the same coconut palm, but it is unlikely to help them move from palm to palm, given that palms usually do not touch each other. PMID:24233102

  4. Eriophyoid mites (Acari: Prostigmata: Eriophyidae) associated with Compositae in Iran.

    PubMed

    Lotfollahi, Parisa; Irani-Nejad, Karim Haddad; Khanjani, Mohamad; Moghadam, Mohamad; De Lillo, Enrico

    2013-01-01

    Five species of eriophyoid mites were identified during surveys of mite fauna associated with plant species of the family Compositae from Southwest of East Azerbaijan province during 2010 and 2011. Two of them, Aceria virgatae n. sp. from Centaurea virgata Lam. and Aceria xeranthenzis n. sp. from Xeranthemumn squarrosum Boiss., were found to be new to science. No damage symptoms were observed on their host plants. Aceria xeranthemis n. sp. is the first eriophyoid collected from the plant genus Xeranthenun. Aculops centaureae (Farkas, 1960) from Centaurea albonitens Turrill and Aceria cichorii Petanović et al. 2000 from Cichorium intybus L. are new records for Iranian mite fauna. The deutogyne female of Aceria anthocoptes (Nalepa) was recorded for the first time in Iran, too. A key to the species collected on Compositae in Iran is given. PMID:26266306

  5. Authentic Learning Experience Prepares Preservice Students to Teach Art to Children with Special Needs

    ERIC Educational Resources Information Center

    Bain, Christina; Hasio, Cindy

    2011-01-01

    Keifer-Boyd and Kraft's (2003) article "Inclusion Policy in Practice" inspired the creation of a new art education course as well as this article. In response to their claim that preservice training should provide greater exposure to experiences with students with special needs, during the summer of 2007 a group of University of North Texas (UNT)…

  6. Phenotypic Differences Among Leipothrix dipsacivagus Pet. et Rector and L. knautiae (Liro) (Acari: Prostigmata: Eriophyidae) Populations Inhabiting Dipsacus L. and Knautia L. (Dipsacaceae) Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Only three eriophyoid mite species of the genus Leipothrix Keifer are known to occur on dipsacaceous plants including hosts in the genera Knautia (L.) Succisa Haller, and Dipsacus L.. These three species are similar, but differ in few key characters. Description of eriophyoids includes over 250 char...

  7. Eriophyoid mites (Acari: Prostigmata: Eriophyoidea) from Turkey: description of five new species.

    PubMed

    Kiedrowicz, Agnieszka; Denizhan, Evsel; Bromberek, Klaudia; Szydło, Wiktoria; Skoracka, Anna

    2016-01-01

    Five new eriophyoid mite species (Eriophyidae) from Turkey are described and illustrated in this paper: Aceria vanensis n. sp., Aceria onosmae n. sp., Aculus lydii n. sp., Aculus gebeliae n. sp. and Aculus spectabilis n. sp.. The descriptions are based on the morphology of females collected from weedy plants, respectively: Amaranthus retroflexus L. (Amaranthaceae), Onosma isauricum Boiss. et Heldr. (Boraginaceae), Hypericum lydium Boiss. (Hypericaceae), Lotus gebelia Vent. (Fabaceae) and Stachys spectabilis Choisy ex DC. (Lamiaceae). The new species were found to be vagrant on their host plants with no visible damage symptoms observed. PMID:27395550

  8. Prospects for Biological Control of Russian thistle (tumbleweed)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    I submitted a petition to the APHIS Technical Advisory Group (TAG) requesting permission to release the blister mite (Aceria salsolae) to control Russian thistle (Salsola tragus) and its close relatives in December 2004. TAG recommended approval for release in Aug. 2005. APHIS-PPQ has not yet issu...

  9. Eriophyoid mites (Acari: Prostigmata: Eriophyoidea) from Hungary: a new species on Agrimonia eupatoria (Rosaceae) and new record on Convolvulus arvensis (Convolvulaceae).

    PubMed

    Ripka, Géza

    2014-01-01

    A new species of eriophyoid mite, Aculus castriferrei n. sp., associated with Agrimonia eupatoria (Rosaceae) is described and illustrated from Hungary. Morphological differences distinguishing this vagrant species from other rosaceous inhabiting congeners are discussed. Aceria malherbae Nuzzaci is a new record for the eriophyoid fauna of Hungary after it was found causing severe damage symptoms to Convolvulus arvensis L. (Convolvulaceae). PMID:25543737

  10. Biological Control of Russian thistle (tumbleweed)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We submitted a petition to the APHIS Technical Advisory Group (TAG) in December 2004 requesting permission to release the blister mite (Aceria salsolae) to control Russian thistle (Salsola tragus) and its close relatives. Host specificity experiments conducted in the USDA quarantine laboratory in ...

  11. Three eriophyoid mite species (Acari: Eriophyoidea: Eriophyidae) from Iran.

    PubMed

    Xue, Xiao-Feng; Sadeghi, Hussein; Honarmand, Arash

    2016-01-01

    Three mite species of the family Eriophyidae from Iran are described and illustrated. They are: Tegolophus marrubiumer sp. nov. on Marrubium vulgare L. (Lamiaceae); Phyllocoptes sp. cf. balasi Farkas, 1962 on Sanguisorba minor Scop. subsp. minor (Rosaceae) and Aceria fasciculifolis sp. nov. on Astragalus fasciculifolius Boiss. (Fabaceae). Both new species described herein are vagrants on their respective host plants. PMID:27395681

  12. The presence of eriophyid mites on native and weed Cirsium species in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aceria anthocoptes is an eriophyid mite that is known to feed on Canada thistle (Cirsium arvense). While this mite species has been considered to be host specific, a detailed evaluation of its host range has yet to be determined. To assess the risks associated with using this mite as a biological ...

  13. Prospects for biological control of Russian thistle (tumbleweed)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We submitted a petition to the APHIS Technical Advisory Group (TAG) requesting permission to release the blister mite (Aceria salsolae) to control Russian thistle (Salsola tragus) and its close relatives was submitted to TAG in December 2004. Host specificity experiments conducted in the quarantin...

  14. Effectiveness of eriophyid mites for biological control of weedy plants and challenges for future research.

    PubMed

    Smith, L; de Lillo, E; Amrine, J W

    2010-07-01

    Eriophyid mites have been considered to have a high potential for use as classical biological control agents of weeds. We reviewed known examples of the use of eriophyid mites to control weedy plants to learn how effective they have been. In the past 13 years, since Rosenthal's 1996 review, 13 species have undergone some degree of pre-release evaluation (Aceria genistae, A. lantanae, Aceria sp. [boneseed leaf buckle mite (BLBM)], A. salsolae, A. sobhiani, A. solstitialis, A. tamaricis, A. thalgi, A. thessalonicae, Cecidophyes rouhollahi, Floracarus perrepae, Leipothrix dipsacivagus and L. knautiae), but only four (A. genistae, Aceria sp. [BLBM], C. rouhollahi and F. perrepae) have been authorized for introduction. Prior to this, three species (Aceria chondrillae, A. malherbae and Aculus hyperici) were introduced and have become established. Although these three species impact the fitness of their host plant, it is not clear how much they have contributed to reduction of the population of the target weed. In some cases, natural enemies, resistant plant genotypes, and adverse abiotic conditions have reduced the ability of eriophyid mites to control target weed populations. Some eriophyid mites that are highly coevolved with their host plant may be poor prospects for biological control because of host plant resistance or tolerance of the plant to the mite. Susceptibility of eriophyids to predators and pathogens may also prevent them from achieving population densities necessary to reduce host plant populations. Short generation time, high intrinsic rate of increase and high mobility by aerial dispersal imply that eriophyids should have rapid rates of evolution. This raises concerns that eriophyids may be more likely to lose efficacy over time due to coevolution with the target weed or that they may be more likely to adapt to nontarget host plants compared to insects, which have a longer generation time and slower population growth rate. Critical areas for future

  15. Eriophyoid mite fauna (Acari: Trombidiformes: Eriophyoidea) of Turkey: new species, new distribution reports and an updated catalogue.

    PubMed

    Denizhan, Evsel; Monfreda, Rosita; Lillo, Enrico De; Çobanoğlu, Sultan

    2015-01-01

    More than one hundred species of Eriophyoidea have been recorded hitherto from Turkey. Within the last decade, a large plant survey was carried out in order to investigate the eriophyoid fauna present in Turkey, with particular emphasis on species affecting weeds and ornamental plants. In addition, the Turkish literature has been examined for previous records of eriophyoid mites. New species, Paraphytoptus intybi n. sp. on common cichory, Cichorium intybus (Compositae) and Phytoptus albae n. sp. on white poplar, Populus alba (Salicaceae), are described and illustrated herein. In addition, a further 31 species were found to be new records for the eriophyoid fauna of Turkey with Aceria calaceris, Phyllocoptes didelphis and Vasates immigrans being new reports for the Palaearctic region. All known eriophyoid species records from Turkey appearing in papers published up until March 2013 are listed in this catalogue along with remarks and information on their current distribution in Turkey and taxonomic status. PMID:26250255

  16. Eriocaenus (Acari: Trombidiformes: Eriophyoidea), a new genus from Equisetum spp. (Equisetaceae): morphological and molecular delimitation of two morphologically similar species.

    PubMed

    Petanović, Radmila U; Amrine, James W; Chetverikov, Philipp E; Cvrković, Tatjana K

    2015-01-01

    Surveys conducted on horsetails, Equisetum spp. (Equisetaceae), in Serbia led to the discovery of a new eriophyoid mite genus while searching for a classical biological control agent against these weeds in New Zealand. Eriocaenus gen. n. is described based on the type species Aceria equiseti Farkas, 1960 (transferred to Eriophyes by Farkas 1965; herein reassigned to the new genus) and Eriocaenus ramosissimi n. sp., a new species discovered on Equisetum ramosissimum Desf. in Serbia. Eriocaenus equiseti (Farkas, 1960), previously only known from Hungary, was found in Serbia for the first time on Equisetum arvense L. and Equisetum telmateia Ehrh., and is redescribed. Species descriptions include line drawings as well as phase contrast (PCLM), differential interference contrast (DIC) and scanning electron (SEM) micrographs. The differential diagnosis between the two Eriocaenus species is supplemented by molecular differentiation of 28S rDNA sequences including D2 fragments for both mites. PMID:26623881

  17. Influence of Life Diet on the Biology and Demographic Parameters of Agistemus olivi Romeih, a Specific Predator of Eriophyid Pest Mites (Acari: Stigmaeidae and Eriophyidae)

    PubMed Central

    Momen, Faten Mamdouh

    2012-01-01

    The influence of various life diets on the biology and demographic parameters of the predatory mite, Agistemus olivi Romeih, was studied under laboratory conditions. A. olivi successfully developed and reproduced on all of the tested eriophyid mites. Feeding on Aceria mangiferae Sayed enhanced the development of A. olivi, resulted in the shortest mean generation time and was the most commensurate food for the ovipostion of the predator, as exhibited by the highest fecundity and net reproductive rate. Preying on Aculops lycopersici (Massee) gave the lowest fecundity and net reproductive rate; therefore, this prey was the least suitable for the oviposition of A. olivi. Preying on Aculus fockeui (Nalepa et Trouessart) and A. mangiferae produced higher intrinsic rates of increase and finite rates of increase for the predator in comparison to A. lycopersici, which showed the lowest value. These differences in response to various eriophyid pests should be considered for the production of healthy cultures of A. olivi. PMID:24575223

  18. Seasonal phoresy as an overwintering strategy of a phytophagous mite.

    PubMed

    Liu, Sai; Li, Jianling; Guo, Kun; Qiao, Haili; Xu, Rong; Chen, Jianmin; Xu, Changqing; Chen, Jun

    2016-01-01

    Migration by attachment to insects is common among mites that live in temporary habitats. However, because plants provide relatively stable habitats, phytophagous mites are generally not dependent on other animals for dispersal, so whether these mites can consistently be phoretic on insects through a particular life stage remains unclear and controversial. Here, we describe an obligate phoresy of a wholly phytophagous mite, Aceria pallida, in which the mites accompanied the psyllid Bactericera gobica to its winter hibernation sites, thus successfully escaping unfavourable winter conditions, and returned to reach the buds of their host plant early the following spring. This finding provides evidence of a new overwintering strategy that has contributed to the evolutionary success of these tiny phytophagous mites. PMID:27150196

  19. Seasonal phoresy as an overwintering strategy of a phytophagous mite

    PubMed Central

    Liu, Sai; Li, Jianling; Guo, Kun; Qiao, Haili; Xu, Rong; Chen, Jianmin; Xu, Changqing; Chen, Jun

    2016-01-01

    Migration by attachment to insects is common among mites that live in temporary habitats. However, because plants provide relatively stable habitats, phytophagous mites are generally not dependent on other animals for dispersal, so whether these mites can consistently be phoretic on insects through a particular life stage remains unclear and controversial. Here, we describe an obligate phoresy of a wholly phytophagous mite, Aceria pallida, in which the mites accompanied the psyllid Bactericera gobica to its winter hibernation sites, thus successfully escaping unfavourable winter conditions, and returned to reach the buds of their host plant early the following spring. This finding provides evidence of a new overwintering strategy that has contributed to the evolutionary success of these tiny phytophagous mites. PMID:27150196

  20. Eriophyoid mites from Northeast China (Acari: Eriophyoidea).

    PubMed

    Xue, Xiao-Feng; Guo, Jing-Feng; Hong, Xiao-Yue

    2013-01-01

    mite records from China are provided, Acaphyllisa distasa (Keifer, 1961) rec. nov. on Betula costata Trautv. (Betulaceae), Shevtchenkella ulmi (Farkas, 1960) rec. nov. on Ulmus sp. (Ulmaceae), Calepitrimerus cariniferus Keifer, 1938, rec. nov. on Artemisia argyi H. Lev. & Vaniot (Asteraceae), Aculodes dubius (Nalepa, 1891) species complex, rec. nov. on Roegneria sp. (Poaceae). With this publication, the number of eriophyoid mite species in the region reaches 101. A list of these eriophyoid mites is provided. PMID:26146687

  1. Traditional and geometric morphometrics supporting the differentiation of two new Retracrus (Phytoptidae) species associated with heliconias.

    PubMed

    Navia, Denise; Ferreira, Cecília B S; Reis, Aleuny C; Gondim, Manoel G C

    2015-09-01

    Cryptic diversity has been confirmed for several phytophagous mites in the Eriophyoidea superfamily previously considered as presenting low host specificity. Among generalist eriophyoids is the phytoptid Retracrus johnstoni Keifer, which has been reported in 19 palm species belonging to 11 genera, causing severe damage on some of them. Surprisingly this species was recently reported on another monocot family, Heliconiaceae, infesting Heliconia plants in Costa Rica and Brazil, being the only in the tribe Mackiellini to not be associated with palm trees. This study aimed to investigate the occurrence of cryptic species in R. johnstoni and to clarify the taxonomic status of populations associated with heliconias in the Americas. With this purpose traditional and geometric morphometric analyses were conducted as well as a detailed morphological study. Measurable trait data were analysed via univariate and multivariate analyses. Shapes of specimens from different populations were compared via geometric morphometric landmark methods. Morphometric analysis supported occurrence of at least two cryptic species previously identified as R. johsntoni and suggested occurrence of cryptic species among populations associated with different palm trees. Taxonomic descriptions of two new taxa associated with heliconias, namely Retracrus costaricensis n. sp. Ferreira and Navia and Retracrus heliconiae n. sp. Ferreira and Navia are presented. Morphometric traits that can be useful in the taxonomic identification are noted and their value is discussed. Results of the traditional morphometry and geometric methods were compared and the advantages of their joint use for Eriophyoidea systematics are discussed. PMID:26089124

  2. Confocal microscopy refines generic concept of a problematic taxon: rediagnosis of the genus Neoprothrix and remarks on female anatomy of eriophyoids (Acari: Eriophyoidea).

    PubMed

    Chetverikov, Philipp E; Desnitskiy, Alexey G; Navia, Denise

    2015-01-01

    Due to the higher resolution, confocal microscopy (CLSM) can be applied to refine the origin of tiny structures of the autofluorescent exoskeletons of microarthropods (mites in particular) which are hard to visualize using traditional differential interference contract light microscopy (DIC LM) and phase contrast light microscopy (PC LM). Three-dimensional (3D) reconstructions of the prodorsal shield topography of eriophyoid mites using Neoprothrix hibiscus Reis and Navia as a model, suggest that the structures originally treated as paired setae vi are two internal rod-like apodemes. Based on this, the genus Neoprothrix is excluded from the subfamily Prothricinae Amrine and transferred to the subfamily Sierraphytoptinae Keifer. Observations on partially cleared specimens of N. hibiscus showed that remnants of the central nervous system, paired glands and developing oocytes can be visualized using DIC LM and CLSM methods. New high quality microscope images are provided of recently described "flower-shaped" structures and two main components of yolk inclusions of the mature eggs inside the oviduct. PMID:25781123

  3. Cryptic speciation within Phytoptus avellanae s.l. (Eriophyoidea: Phytoptidae) revealed by molecular data and observations on molting Tegonotus-like nymphs.

    PubMed

    Cvrković, Tatjana; Chetverikov, Philipp; Vidović, Biljana; Petanović, Radmila

    2016-01-01

    Hazelnut big bud mite, Phytoptus avellanae Nalepa, is one of the most harmful pests of Corylus spp. (Corylaceae) worldwide. Herein, we show that this species represents a complex of two cryptic species: one that lives and reproduces in buds causing their enlargement ('big buds') and drying, whereas the other is a vagrant living on leaves, under bud scales and in catkins, based on phylogenetic analyzes of mitochondrial cytochrome c oxidase subunit I (COI) DNA and the nuclear D2 region of 28S rDNA sequences. A molecular assessment based on mtCOI DNA and nuclear D2 28S rDNA revealed consistent differences of 16.8 and 3.5% between the two species, respectively. Molecular analysis also revealed that atypical flattened nymphs (Tegonotus-like nymphs sensu Keifer in Mites Injurious to Economic Plants, University of California Press, Berkeley, pp 327-562, 1975) with differently annulated opisthosoma, which appear in the life cycle of P. avellanae s.l., belong to the 'vagrant' lineage, i.e. vagrant cryptic species. Light microscopy images of Tegonotus-like nymphs molting into males and females are presented for the first time. Our results suggest that the name P. avellanae comprise two species. Big bud mite should keep the name P. avellanae, and the vagrant cryptic species should be re-named after a proper morphological description is made. PMID:26530992

  4. Acarological diagnostic research at the Diagnostic Centre for Plants during the period 2004-2006.

    PubMed

    Witters, J; De Bondt, G; Desamblanx, J; Casteels, H

    2007-01-01

    During the period 2004-2006, 1691 samples of different origin were examined at the Diagnostic Centre for Plants. We received 1046 samples of imported plant material for detection and identification of quarantine organisms. More than 200 samples were checked on mites and insects to get a phytosanitary certificate for export and 391 samples were investigated for diagnostic reason. The Berlese-funnel and dissecting microscopy technique were used to separate mites from the samples. For identification, the mites were slide mounted in Berlese-Hoyer's medium and examined by using phase-contrast microscopy. In 3% of the samples examined on the presence of quarantine organisms, phytophagous mites belonging to the superfamily Tetranychoidea were found, but none with the quarantine status in accordance with the EPPO A1/A2 list. Besides Tetranychus urticae detected on different crops, the cassava green mite Mononychellus progresivus was found on cassava (import Cameroon) in 2006. Tenuipalpus elegans (Tenuipalpidae) was found on cut foliage (import South Africa) in 2004. In 19.9% of the investigated samples for diagnostic reason mites were found. In 47.7% of the infested samples mites were definitely the reason for the damage; in 15.9% mites were secondary and in 36.4% the occurrence of mites was not relevant for the injury. An overview of the determined mites will be given. During this 3 years diagnostic research a few new pest mites belonging to families Tetranychidae and Eriophyidae can be reported. In 2006 Panonychus citri was found on Prunus laurocerasus and later on Eleaegnus sp. and Skimmia sp.. Aceria silvicola was determined on Rubus idaeus in 2006 and Aculus ulae and Aceria carpini on Carpinus betulus in 2005. Besides new pest mites, never seen problems with the broad mite Polyphagotarsonemus latus (Fam. Tarsonemidae) occurred in tree-nurseries in 2005 and 2006. Also 20 samples coming from private persons were investigated. The main problems indoor were caused by

  5. Secondary structure of expansion segment D1 in LSU rDNA from Arachnida and its phylogenetic application in Eriophyoid mites and in Acari.

    PubMed

    Wang, Zheng-Hang; Zhao, Ya-E; Xu, Yang; Hu, Li; Chen, Yi-Meng

    2015-12-01

    An increasing number of researchers have applied secondary-structure based multiple alignments of rDNA genes in phylogeny. These studies mostly depended on a few valuable divergent domains in LSU and SSU rDNA. Yet other divergent domains, e.g. D1, were poorly investigated and rarely used. However, these domains might contain additional evolutionary data and play a vital role in DNA-based phylogenetic study. Here, we investigated all available D1 sequences of Arachnida taxa and predicted corresponding secondary structures to help identify homologous positions in the D1 region. Long insertions were found exclusive to Eriophyoidea and folded into three newly proposed helices. Non-Acari taxa were all GC rich. In Acari, most Trombidiformes and all Mesostigmata (Parasitiformes) taxa were AT rich and Ixodida (Parasitiformes) GC rich; however there was no consistent base bias in Sarcoptiformes sequences. For Eriophyoid mites, genera Cecidophyopsis and Aceria were both well supported in MP, NJ, ME and ML tress based on D1 sequences, and clusters of Cecidophyopsis species were identical with former study. This demonstrated that the D1 region could act as a valuable molecular marker in phylogenetic reconstruction of Eriophyoidea. Additionally, D1 has been proven suitable in phylogenetic analysis at the family and genus level in Acari, but not in Opiliones. PMID:26420464

  6. Population-level effects of abamectin, azadirachtin and fenpyroximate on the predatory mite Neoseiulus baraki.

    PubMed

    Lima, Debora B; Melo, José W S; Gondim, Manoel G C; Guedes, Raul N C; Oliveira, José E M

    2016-10-01

    The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki. PMID:27495808

  7. Identification of Coupling and Repulsion Phase DNA Marker Associated With an Allele of a Gene Conferring Host Plant Resistance to Pigeonpea sterility mosaic virus (PPSMV) in Pigeonpea (Cajanus cajan L. Millsp.)

    PubMed Central

    Daspute, Abhijit; Fakrudin, B.

    2015-01-01

    Pigeonpea Sterility Mosaic Disease (PSMD) is an important foliar disease caused by Pigeonpea sterility mosaic virus (PPSMV) which is transmitted by eriophyid mites (Aceria cajani Channabasavanna). In present study, a F2 mapping population comprising 325 individuals was developed by crossing PSMD susceptible genotype (Gullyal white) and PSMD resistant genotype (BSMR 736). We identified a set of 32 out of 300 short decamer random DNA markers that showed polymorphism between Gullyal white and BSMR 736 parents. Among them, eleven DNA markers showed polymorphism including coupling and repulsion phase type of polymorphism across the parents. Bulked Segregant Analysis (BSA), revealed that the DNA marker, IABTPPN7, produced a single coupling phase marker (IABTPPN7414) and a repulsion phase marker (IABTPPN7983) co-segregating with PSMD reaction. Screening of 325 F2 population using IABTPPN7 revealed that the repulsion phase marker, IABTPPN7983, was co-segregating with the PSMD responsive SV1 at a distance of 23.9 cM for Bidar PPSMV isolate. On the other hand, the coupling phase marker IABTPPN7414 did not show any linkage with PSMD resistance. Additionally, single marker analysis both IABTPPN7983 (P<0.0001) and IABTPPN 7414 (P<0.0001) recorded a significant association with the PSMD resistance and explained a phenotypic variance of 31 and 36% respectively in F2 population. The repulsion phase marker, IABTPPN7983, could be of use in Marker-Assisted Selection (MAS) in the PPSMV resistance breeding programmes of pigeonpea. PMID:25774108

  8. Deep sequencing of dsRNAs recovered from mosaic-diseased pigeonpea reveals the presence of a novel emaravirus: pigeonpea sterility mosaic virus 2.

    PubMed

    Elbeaino, Toufic; Digiaro, Michele; Uppala, Mangala; Sudini, Harikishan

    2015-08-01

    Deep-sequencing analysis of double-stranded RNA extracted from a mosaic-diseased pigeonpea plant (Cajanus cajan L., family Fabaceae) revealed the complete sequence of six emaravirus-like negative-sense RNA segments of 7009, 2229, 1335, 1491, 1833 and 1194 nucleotides in size. In the order from RNA1 to RNA6, these genomic RNAs contained ORFs coding for the RNA-dependent RNA polymerase (RdRp, p1 of 266 kDa), the glycoprotein precursor (GP, p2 of 74.5 kDa), the nucleocapsid (NC, p3 of 34.9 kDa), and the putative movement protein (MP, p4 of 40.7 kDa), while p5 (55 kDa) and p6 (27 kDa) had unknown functions. All RNA segments showed distant relationships to viruses of the genus Emaravirus, and in particular to pigeonpea sterility mosaic virus (PPSMV), with which they shared nucleotide sequence identity ranging from 48.5 % (RNA3) to 62.5 % (RNA1). In phylogenetic trees constructed from the sequences of the proteins encoded by RNA1, RNA2 and RNA3 (p1, p2 and p3), this new viral entity showed a consistent grouping with fig mosaic virus (FMV) and rose rosette virus (RRV), which formed a cluster of their own, clearly distinct from PPSMV-1. In experimental greenhouse trials, this novel virus was successfully transmitted to pigeonpea and French bean seedlings by the eriophyid mite Aceria cajani. Preliminary surveys conducted in the Hyderabad region (India) showed that the virus in question is widespread in pigeonpea plants affected by sterility mosaic disease (86.4 %) but is absent in symptomless plants. Based on molecular, biological and epidemiological features, this novel virus is the second emaravirus infecting pigeonpea, for which the provisional name pigeonpea sterility mosaic virus 2 (PPSMV-2) is proposed. PMID:26060057

  9. Synaptic control of hindlimb motoneurones during three forms of the fictive scratch reflex in the turtle.

    PubMed Central

    Robertson, G A; Stein, P S

    1988-01-01

    1. The turtle spinal cord produces three forms of the fictive scratch reflex in response to tactile stimulation of sites on the body surface. Common to all three forms is the rhythmic alternation of activity between hip protractor and hip retractor motoneurones. Hip protractor motoneurone activity is monitored via nerves innervating the hip protractor muscle puboischiofemoralis internus pars anteroventralis (VP-HP). Hip retractor activity is monitored via nerves innervating several monoarticular hip retractor muscles, one hip adductor muscle, and several biarticular hip retractor-knee flexor muscles (HR-KF). Each form is characterized by the timing of activity of motoneurones innervating femorotibialis (FT-KE), a monoarticular knee extensor muscle, within this alternating cycle (Robertson, Mortin, Keifer & Stein, 1985). In the present study, intracellular recordings revealed a corresponding regulation of synaptic drive to knee extensor motoneurones with respect to the synaptic drive to the motoneurones innervating antagonist muscles of the hip. These patterns of synaptic activation give rise to the distinct motor pattern underlying each form of the scratch reflex. 2. VP-HP, HR-KF and FT-KE motoneurones all exhibited phasic depolarizing and hyperpolarizing changes in membrane voltage during the production of the rhythmic motor patterns underlying each stratch form. Membrane depolarization is caused by synaptic excitation (EPSPs) and gives rise to motoneurone discharge. Hyperpolarization is primarily the result of postsynaptic inhibition (IPSPs) mediated by an increased conductance of chloride ions (Cl-) and ensures motor pool quiescence during antagonist activation. 3. VP-HP motoneurones depolarized during activation of the VP-HP motor pool and hyperpolarized during activation of the HR-KF motor pool. HR-KF motoneurones depolarized during activation of the HR-KF motor pool and hyperpolarized during activation of the VP-HP motor pool. In many cases, the amplitude of

  10. Neoseiulus paspalivorus, a predator from coconut, as a candidate for controlling dry bulb mites infesting stored tulip bulbs.

    PubMed

    Lesna, Izabela; da Silva, Fernando R; Sato, Yukie; Sabelis, Maurice W; Lommen, Suzanne T E

    2014-06-01

    The dry bulb mite, Aceria tulipae, is the most important pest of stored tulip bulbs in The Netherlands. This tiny, eriophyoid mite hides in the narrow space between scales in the interior of the bulb. To achieve biological control of this hidden pest, candidate predators small enough to move in between the bulb scales are required. Earlier experiments have shown this potential for the phytoseiid mite, Neoseiulus cucumeris, but only after the bulbs were exposed to ethylene, a plant hormone that causes a slight increase in the distance between tulip bulb scales, just sufficient to allow this predator to reach the interior part of the bulb. Applying ethylene, however, is not an option in practice because it causes malformation of tulip flowers. In fact, to prevent this cosmetic damage, bulb growers ventilate rooms where tulip bulbs are stored, thereby removing ethylene produced by the bulbs (e.g. in response to mite or fungus infestation). Recently, studies on the role of predatory mites in controlling another eriophyoid mite on coconuts led to the discovery of an exceptionally small phytoseiid mite, Neoseiulus paspalivorus. This predator is able to move under the perianth of coconuts where coconut mites feed on meristematic tissue of the fruit. This discovery prompted us to test N. paspalivorus for its ability to control A. tulipae on tulip bulbs under storage conditions (ventilated rooms with bulbs in open boxes; 23 °C; storage period June-October). Using destructive sampling we monitored predator and prey populations in two series of replicated experiments, one at a high initial level of dry bulb mite infestation, late in the storage period, and another at a low initial dry bulb mite infestation, halfway the storage period. The first and the second series involved treatment with N. paspalivorus and a control experiment, but the second series had an additional treatment in which the predator N. cucumeris was released. Taking the two series of experiments together

  11. Pathogenicity of Fusarium semitectum against crop pests and its biosafety to non-target organisms.

    PubMed

    Mikunthan, G; Manjunatha, M

    2006-01-01

    Microbial control is receiving more attention, since these alternative tactics, compared to chemical control methods, are energy saving, non polluting, ecologically sound and sustainable. A mycopathogen, Fusarium semitectum Berk. and Rav. (ARSEF 7233) was isolated from diseased cadavers of aphid (Aphis gossypii) and cultured in Saboraud Maltose Agar supplemented with Yeast extract medium (SMAY). Being isolated first time from the chilli ecosystem its potential was evaluated. Experiments were conducted to understand its pathogenicity against crop pests as well as to ensure its safety to non target organisms such as silk worm (Bombyx mor), honey bee (Apis indica) and earthworm (Eisenia foetida). A paper-thrips-paper sandwich method for thrips and detached-leaf bioassay method for mites were used. Test insects and mites either reared in laboratory or obtained from the field were topically applied with spore suspension of F. semitectum (1x10(9) spores/ml). Mortality was recorded and dead animals were surface sterilized with 0.5% NaOCl and placed in SMAY medium to confirm pathogenicity. Mulberry leaves sprayed with the fungal suspension were fed to larvae of B. mori and reared. Newly emerged A. indica were topically applied with fungus. The fungus grown in cow dung for two weeks was used to assess the composting ability of E. foetida. F. semitectum produced mycosis and caused mortality to sucking pests such as chilli thrips (Scirtothrips dorsalis), broad mite (Polyphagotarsonemus latus), sugarcane wooly aphid (Ceratavacuna lanigera), spiraling whitefly (Aleyrodicus disperses), whitefly (Bemisia tabaci, A. gossypii and coconut mite (Aceria guerroronis). The fungus did not cause mortality on larvae of lepidopteran insect pests and ladybird beetle (Menochilus sexmaculatus), predatory mite (Amblysius ovalis) and larval parasitoid (Goniozus nephantidis). F. semitectum failed to infect the larvae of B. mori and newly emerged A. indica and its brood. The mycopathogen had no