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Sample records for neoseiulus womersleyi schicha

  1. The endosymbionts Wolbachia and Cardinium and their effects in three populations of the predatory mite Neoseiulus paspalivorus

    NARCIS (Netherlands)

    Sourassou, N.F.; Hanna, R.; Breeuwer, J.A.J.; Negloh, K.; de Moreas, G.J.; Sabelis, M.W.

    2014-01-01

    Whereas endosymbiont-induced incompatibility is known to occur in various arthropod taxa, such as spider mites, insects and isopods, it has been rarely reported in plant-inhabiting predatory mites (Acari: Phytoseiidae). Recent cross-breeding studies with the phytoseiid mite Neoseiulus paspalivorus D

  2. The effect of repeated release of the predatory mite Neoseiulus (Amblyseius) cucumeris on arthropod communities in citrus ecosystems

    OpenAIRE

    Jie Ji; Yanxuan Zhang; Xia Chen; Jianzhen Lin; Li Sun

    2012-01-01

    In order to study the effect of repeated release of Neoseiulus (Amblyseius) cucumeris on the species composition and diversity of arthropod community in citrus ecosystems, we established bio-control orchards, natural orchards and chemical control orchards in the Mawei and Jin’an experimental field of Fuzhou, China. Our results indicated that the species richness of bio-control orchards was higher than that of natural or chemical control orchards at both sites. Diversity and evenness indices w...

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

    Science.gov (United States)

    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.

  4. How do Neoseiulus californicus (Acari: Phytoseiidae) females penetrate densely webbed spider mite nests?

    Science.gov (United States)

    Montserrat, M; de la Peña, F; Hormaza, J I; González-Fernández, J J

    2008-02-01

    The persea mite Oligonychus perseae is a pest of avocado trees that builds extremely dense webbed nests that protect them against natural enemies, including phytoseiid mites. Nests have one or two marginal entrances that are small and flattened. The predatory mite Neoseiulus californicus co-occurs with O. perseae in the avocado orchards of the south-east of Spain. Penetration inside nests through the entrances by this predator is thought to be hindered by its size and its globular-shaped body. However, in the field it has repeatedly been found inside nests that were clearly ripped. Perhaps penetration of the nests has been facilitated by nest wall ripping caused by some other species or by unfavourable abiotic factors. However, to assess whether N. californicus is also able to enter the nest of O. perseae by itself, we carried out laboratory experiments and made a short film. They show how this predator manages to overcome the webbed wall, and that it can penetrate and forage inside nests of O. perseae.

  5. Bioinsecticide-predator interactions: azadirachtin behavioral and reproductive impairment of the coconut mite predator Neoseiulus baraki.

    Science.gov (United States)

    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.

  6. Bioinsecticide-predator interactions: azadirachtin behavioral and reproductive impairment of the coconut mite predator Neoseiulus baraki.

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    Debora B Lima

    Full Text Available 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.

  7. SELETIVIDADE DE INSETICIDAS A Neoseiulus californicus MCGREGOR (ACARI: PHYTOSEIIDAE EM MACIEIRA, NO RIO GRANDE DO SUL AGROCHEMICAL SELECTIVITY TO Neoseiulus californicus MCGREGOR (ACARI: PHYTOSEIIDAE ON APPLE IN RIO GRANDE DO SUL

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    LINO BITTENCOURT MONTEIRO

    2001-12-01

    Full Text Available Testes para determinar os efeitos de agroquímicos homologados para macieira foram realizados em laboratório sobre Neoseiulus californicus (Acari: Phytoseiidae. Os indivíduos testados foram coletados de um pomar comercial da Agriflor Ltda, em Vacaria, Rio Grande do Sul, após várias liberações inoculativas. Os inseticidas utilizados foram os tradicionalmente recomendados para o controle de pragas, principalmente mosca-das-frutas Anastrepha fraterculus (Diptera: Tephritidae. A oviposição e a mortalidade dos ácaros foram avaliadas 12; 24; 48 e 96 horas após a pulverização, cujos produtos foram classificados em quatro classes de toxicidade (IOBC/WPRS. Azinphos ethyl, deltametrina e fenthion provocaram 100% de mortalidade, sendo que dimethoate, fenitrotion, paration, phosmet e triclorfon foram levemente nocivos (classe 2. Malation foi considerado neutro para esta população.The side-effects of agrochemical to Neoseiulus californicus (Acari: Phytoseiidae were studied in laboratory. The mites were collected in commercial apple orchard of Agropastoril Rincão das Flores, in Vacaria, Rio Grande do Sul, Brazil, after successive inoculative releases. The insecticids used were recommended to control of same pest, as Anastrepha fraterculus (Diptera: Tephritidae. The reproduction effect and mortality were evalued 12, 24, 48 and 96 hours after pulverization, while the agrochemical were ranked in toxicity classes, according to IOBC/WPRS. Azinphos ethyl, deltametrina e fenthion were harmful with ca. 100% of mortality in 24 hours, dimethoate, fenitrotion, paration, phosmet e triclorfon were slightly harmful (class 2. Malation was harmless.

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

    Science.gov (United States)

    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

  9. Cannibalism and intraguild predation of phytoseiid mites Neoseiulus barkeri and Neoseiulus cucumeris%两种植绥螨的同类相残和集团内捕食作用

    Institute of Scientific and Technical Information of China (English)

    彭勇强; 孟瑞霞; 张东旭; 张鹏飞; 韩玉花

    2013-01-01

    Phytoseiid mites Neoseiulus barkeri and N.cucumeris are the generalists mainly preying on spider mites and thrips,and widely used in agricultural bio-control.In this paper,the cannibalism and intraguild predation of N.barkeri and N.cucumeris and the female aggressiveness on larvae (quantified as attack probability) in intraguild predation were studied,aimed to elucidate the interrelationships between these two species of predatory mite to reasonably establish a combination of different natural enemies in biological control.The results showed that the phytoseiid mites consumed more con-and heterospecific larvae,lesser protonymphs,and seldom con-and heterospecific eggs.The adult females of the two species mites exhibited higher predation rates on heterospecific larvae and protonymphs than on conspecific larvae and protonymphs,suggesting that the two species of mites preferentially engaged in intraguild predation in absence of other food sources.The predation rate of N.barkeri on heterospecific larvae and protonymphs was higher than that of N.cucumeri.Moreover,N.barkeri was more aggressive to heterospecific larvae than N.cucumeri in intraguild predation.Therefore,N.barkeri was most probably a potential intraguild predator of N.cucumeris,whereas N.cucumeri was a potential intraguild prey when the intraguild predation occurred between N.barkeri and N.cucumeris.%巴氏新小绥螨(Neoseiulus barkeri)和黄瓜新小绥螨(N.cucumeris)是两种多食性植绥螨,主要捕食叶螨和蓟马等,目前在我国广泛应用于农业生物防治中.本文研究了这两种植绥螨种内的同类相残(cannibalism)和种间的集团内捕食作用(intraguild predation)以及相互之间的攻击强度,以明确两者之间的相互关系,为合理构建天敌组合及评估生物防治的作用提供依据.结果显示:两种植绥螨对同种或异种幼螨的捕食量最大,其次是若螨,而对卵的捕食量极低.两种植绥螨对异种幼螨或若螨的捕食量均极

  10. Seletividade de agrotóxicos usados na cultura da macieira a Neoseiulus Californicus (McGregor (Acari: Phytoseiidae1 Pesticide selectivity used in apple crops Neoseiulus californicus (McGregor (Acari: Phytoseiidae

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    Geraldine de Andrade Meyer

    2009-06-01

    Full Text Available Objetivou-se avaliar os efeitos secundários dos principais agrotóxicos utilizados em macieira sobre adultos e imaturos de Neoseiulus californicus (McGregor (Acari: Phytoseiidae. Os testes foram conduzidos em laboratório, utilizando as doses dos produtos recomendadas para a cultura e o método de contato e residual com pulverização em superfície de folha. Foram testados tebufenozida, fosmete, metidationa, clorpirifós, abamectina, fenpiroximato, piridabem, captana, mancozebe (duas dosagens e ditianona. Para o cálculo do efeito total (E% sobre os adultos, avaliaram-se a mortalidade, a oviposição e a viabilidade dos ovos, e para os imaturos, somente a mortalidade. Os resultados do E% foram avaliados 96 horas após a pulverização. Os produtos foram classificados quanto ao efeito total (E% de toxicidade proposta pela IOBC/WPRS. Fosmete, tebufenozida e metidationa foram inócuos; abamectina, fenpiroximato, clorpirifós, captana, mancozebe (nas duas dosagens testadas e ditianona foram levemente nocivos, e piridabem foi moderadamente nocivo aos adultos de N. californicus. O fungicida mancozebe, na maior dosagem (320g,i.a./100L, foi o que mais afetou o ácaro predador. Quanto à seletividade dos agrotóxicos aos imaturos, constatouse que abamectina e piridabem foram moderadamente nocivos, e os demais foram inócuos. Nenhum produto foi classificado como nocivo, evidenciando a tolerância de N. californicus a estes agrotóxicos. Estes resultados permitem uma escolha e manejo mais adequado para os agrotóxicos utilizados nos pomares comerciais de macieira, de forma que a presença deste ácaro predador exerça pressão de controle do ácaro-vermelho.The objective of this study was to evaluate the side effects of the main pesticides used in adult and immature Neoseiulus californicus (McGregor (Acari: Phytoseiidae. The tests were carried out in the laboratory by using the contact and residual spraying method on the leaf surface. It was tested

  11. Conservation biological control in strawberry: effect of different pollen on development, survival, and reproduction of Neoseiulus californicus (Acari: Phytoseiidae).

    Science.gov (United States)

    Gugole Ottaviano, María F; Cédola, Claudia V; Sánchez, Norma E; Greco, Nancy M

    2015-12-01

    Wild vegetation surrounding crops may provide temporary habitat and potential food sources for phytoseiids in different seasons. Monthly vegetation samples of wild plants adjacent to strawberry plants and wild plants in a vegetation strip close to the crop were taken. The frequency of Neoseiulus californicus, Tetranychus urticae and other mites and insects was recorded. In addition, in a laboratory assay, the survival, developmental time and fecundity of females fed on pollen of strawberry and pollen of wild plants where N. californicus was recorded during their flowering, were estimated. Pollen from Urtica urens, Lamium amplexicaule, Convolvulus arvensis, Sonchus oleraceous, Galega officinalis, and Fragaria x ananassa (strawberry) allowed development of N. californicus to adult, but not reproduction. Survival was 70-80 % when fed on pollen from S. oleraceus, G. officinalis and C. arvensis, 80-90 % when fed on pollen from U. urens and F. x ananassa, and more than 90 % when fed on T. urticae and on pollen from L. amplexicaule. In autumn and winter, U. urens, L. amplexicaule and S. oleraceous could promote the persistence of N. californicus when prey density in strawberry is low, offering T. urticae, thrips and pollen. In summer, pollen of C. arvensis and G. officinalis would contribute to the persistence of N. californicus when the strawberry crop is ending and offers scarce food resources. Although the pollen of these plants would not enable the predator population to increase, the presence of these plants in the vicinity of strawberry could contribute to the persistence of N. californicus population and help to limit T. urticae growth when this pest begins to colonize the crop.

  12. Toxicity of essential oils of Piper marginatum Jacq. against Tetranychus urticae Koch and Neoseiulus californicus (McGregor

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    Nicolle Ribeiro

    2016-03-01

    Full Text Available Tetranychus urticae Koch (Acari: Tetranychidae is an economically important pest of agricultural and ornamental crops worldwide. It has been shown that many of natural plant-based pesticides have fewer side effects compared with synthetic chemicals. The essential oils of plants have been broadly studied for pest-control, including toxic and repellent effects, antifeedant, ovicidal, and other properties. Essential oils from stems, flowers, and leaves of Piper marginatum Jacq. were evaluated in the laboratory regarding their acaricidal potential against the two-spotted spider mite (T. urticae and the results were compared with eugenol as a positive control. The oils were also evaluated with regard to the susceptibility of the natural enemy of T. urticae (Neoseiulus californicus McGregor. Based on LC50 estimates, oils from stems and flowers exhibited the same toxicity and differed significantly from the leaf oil with LC50 0.37, 0.56, and 3.77 μL L-1, respectively. None of the oils tested exhibited toxicity greater than or equal to that of the positive control. The oil mortality rate was significantly lower for N. californicus (50% to 70% than for T. urticae (> 95%. The P. marginatum oils also deterred oviposition. Among the chemical constituents tested, sesquiterpenes were more toxic with an LC50 of 2.89 μL L-1 than phenylpropanoids Z-asarone and E-asarone with LC50 6.64 and 8.51 μL L-1, respectively. The acaricidal properties, oviposition deterrence and selectivity make these oils strong candidates for use as the active ingredient in a plant-based acaricidal agent.

  13. Intraguild predation among Scolothrips longicornis (Thysanoptera: Thripidae), Neoseiulus californicus and Typhlodromus bagdasarjani (Acari: Phytoseiidae) under laboratory conditions.

    Science.gov (United States)

    Farazmand, Azadeh; Fathipour, Yaghoub; Kamali, Karim

    2015-04-01

    This study was carried out on the ability of predatory thrips Scolothrips longicornis Priesner to feed on 2 phytoseiid species and vice versa. Also the effect of predation of Neoseiulus californicus (McGregor) on Typhlodromus bagdasarjani Wainstein and Arutunjan and vice versa was evaluated. The larvae, prepupae, and pupae of thrips and the eggs, larvae, and protonymphs of phytoseiids were selected as intraguild prey. The intraguild predation (IGP) among S. longicornis and 2 phytoseiid species was unidirectional and in favor of phytoseiids, i.e., S. longicornis was not able to feed on larval stages of 2 phytoseiids. However, N. californicus and T. bagdasarjani fed on the 1st instar larvae (1.39 and 0.80 per day), 2nd instar larvae (0.87 and 0.55 per day), prepupae (0.51 and 0.48 per day), and pupae of thrips (0.51 and 0.49 per day, respectively). Both phytoseiids fed on eggs, larvae, and protonymphal stages of each other. Females of N. californicus consumed more phytoseiid larvae (2.49 per day) than T. bagdasarjani, which consumed 1.08 N. californicus larvae per day. When Tetranychus urticae was presented as an extraguild prey, intensity of IGP between 2 species of phytoseiids and on larval stages of S. longicornis reduced significantly. Therefore, it is concluded that (i) IGP existed among the 3 examined species and lack of feeding of S. longicornis on 2 phytoseiid species can be justified by its feeding type (monophagy), (ii) N. californicus was much more prone to IGP than was T. bagdasarjani. © 2013 Institute of Zoology, Chinese Academy of Sciences.

  14. Risk assessment of Cry toxins of Bacillus thuringiensis on the predatory mites Euseius concordis and Neoseiulus californicus (Acari: Phytoseiidae).

    Science.gov (United States)

    de Castro, Thiago Rodrigues; Ausique, John Jairo Saldarriaga; Nunes, Daiane Heloisa; Ibanhes, Fernando Henrique; Delalibera Júnior, Italo

    2013-04-01

    Genetically modified plants carrying Cry toxins of Bacillus thuringiensis (Bt) are widely used for pest control. Possible adverse effects as a result of the use of this control technique to non-target organisms is still a concern; however, few studies have addressed the effects of Bt crops on phytoseiid predatory mites. Phytoseiids are important for the natural control of phytophagous mites, but they can also feed on pollen, plant exudates, etc. Thus, phytoseiids may ingest Bt toxins through several pathways. In this paper, we evaluate the direct effect of Bt-toxins by feeding the predators on Bt cell suspensions, on solution of a Bt toxin and the tri-trophic effect by Bt expressed in transgenic plants. We present a method of conducting toxicological tests with Phytoseiidae which can be useful in studies of risk analysis of toxins to be expressed by genetically engineered plants. This method was used to evaluate the potential effect of ingestion of suspensions of Bt (1.25 × 10(8) spores/ml) and of purified protein Cry1Ia12 (0.006 mg/ml and 0.018 mg/ml) on Euseius concordis, a predatory mite that develops and reproduces best on pollen. The effects of genetically modified Bollgard(®) cotton, which carries the Cry1Ac protein, on Neoseiulus californicus, a selective predator that feeds more on spider mites than on pollen or insects, was determined by feeding them with Tetranychus urticae reared in Bollgard(®) cotton and on the non-transgenic isoline. When E. concordis was fed with suspension of Bt isolate derived from product Dipel(®) PM, no significant effects were detected. Similarly, Cry1Ia12 Bt toxin, at a concentration of 0.006 mg/ml, did not affect E. concordis. At a concentration of 0.018 mg/ml, however, the intake of this protein reduced the reproduction of E. concordis. There were no effects of Bollgard(®) cotton on the biological traits and on the predatory capacity of N. californicus. Results indicate that the Cry toxins of B. thuringiensis

  15. Toxicidade residual de alguns agrotóxicos recomendado na agricultura sobre Neoseiulus californicus (McGregor (Acari: Phytoseiidae Residual toxicity of some pesticides recommended for citrus orchards on the predaceous mite Neoseiulus californicus (McGregor (Acari: phytoseiidae

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    Marcos Zatti da Silva

    2007-04-01

    Full Text Available O objetivo do trabalho foi avaliar a toxicidade residual de alguns agrotóxicos utilizados em citros sobre Neoseiulus californicus (McGregor em condições de laboratório. O método de bioensaio adotado foi o de contato residual. Folhas de citros da variedade Pêra, acondicionadas em arenas, foram pulverizadas em torre de Potter. A toxicidade residual dos produtos foi avaliada duas horas e 1; 3; 5; 7; 10; 14 e 21 dias após a aplicação. Em cada arena, foram transferidas dez fêmeas adultas de N. californicus, juntamente com uma quantidade suficiente de Tetranychus urticae, como fonte de alimento. As avaliações de mortalidade foram realizadas 72 horas após a transferência dos ácaros para as arenas. Os agrotóxicos acrinathrin, deltamethrin, dinocap, enxofre, fenpropathrin, óxido de fenbutatin e propargite não causaram mortalidades significativas em adultos de N. californicus. Foram registradas mortalidades de 29,8; 24,0 e 34,1% para ácaros N. californicus expostos a resíduos de duas horas de idade de abamectim, azocyclotin e cyhexatin, respectivamente. Dicofol, pyridaben e chlorfenapyr causaram 100% de mortalidade aos ácaros predadores expostos aos resíduos tóxicos dos acaricidas, com duas horas de idade. Abamectin provocou mortalidade significativa por um período inferior a um dia. Resíduos dos acaricidas azocyclotin, cyhexatin, dicofol, pyridaben e chlorfenapyr provocaram mortalidades significativas por períodos de 1; 1; 10; 10 e 21dias, respectivamente. Os resultados obtidos no presente experimento servem de subsídio para a escolha adequada dos agrotóxicos a serem utilizados em pomares de citros nos quais N. californicus esteja presente ou naqueles em que o predador venha a ser liberado. Esses resultados também servem para a escolha do momento mais favorável para a liberação dos ácaros predadores dessa espécie no campo, após a aplicação de agrotóxicos nos pomares. Estudos conduzidos em condições de campo ainda s

  16. Mortalidade do ácaro predador Neoseiulus californicus (Acari: Phytoseiidae em testes de toxicidade residual de inseticidas e acaricidas usuais em pomáceas Mortality of predatory mite Neoseiulus californicus (Acari: Phytoseiidae in residual toxicity persistence tests

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    Marcelo Gustavo Ruiz

    2008-12-01

    Full Text Available Os ácaros fitoseídeos, especialmente Neoseiulus californicus (McGregor, são importantes agentes de controle biológico de ácaros tetraniquídeos-praga nas culturas de pomáceas no "Alto Valle del Río Negro y Neuquén", Argentina. Neste trabalho, avaliou-se a mortalidade de N. californicus quando exposto a resíduos dos inseticidas azimphos-methyl, carbaryl e cyfluthrin, e dos acaricidas cyhexatin e propargite. Os produtos foram aplicados às concentrações recomendadas em plantas de pereira. Um, três, seis e dez dias após a aplicação (DAA, folhas tratadas foram retiradas das plantas para a preparação de unidades experimentais. Cinco adultos de N. californicus, provenientes de criação-estoque, foram transferidos para cada unidade, onde pólen de taboa foi fornecido como alimento. As unidades foram mantidas a 25 ± 2 ºC, 60 ± 10% de umidade relativa e fotoperíodo de 14 h. A mortalidade do ácaro foi avaliada 24 h após o confinamento. As médias de mortalidade foram comparadas pelo teste de Dunnett, a 5% de probabilidade. A progressão do declínio do efeito dos produtos testados foi submetida à análise de regressão. Nas duas primeiras datas de avaliação, todos os produtos apresentaram valores de mortalidade significativamente diferentes da testemunha tratada com água. Seis dias após a aplicação, propargite, cyhexatin e cyfluthrin apresentaram mortalidade de aproximadamente 30%, enquanto a mortalidade nos tratamentos azimphos-methyl e carbaryl apresentou níveis estatisticamente similares aos da testemunha. Dez dias após a aplicação, a mortalidade em todos os tratamentos não diferiu significativamente da testemunha. O efeito de todos os produtos apresentou declínio progressivo ao longo do período de observação, sendo significativa a 1% de probabilidade a regressão linear negativa para os valores obtidos. Os maiores efeitos negativos sobre a sobrevivência de N. californicus corresponderam aos acaricidas testados

  17. Oviposição dos ácaros predadores Agistemus floridanus Gonzalez, Euseius concordis (Chant e Neoseiulus anonymus (Chant & Baker (Acari em resposta a diferentes tipos de alimento Oviposition of the predators Agistemus floridanus Gonzalez, Euseius concordis (Chant and Neoseiulus anonymus (Chant & Baker (Acari in response the different kinds of food

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    Noeli Juarez Ferla

    2003-03-01

    Full Text Available Phytoseiidae and Sigmaeidae are the most common predatory mites on rubber tree leaves in the State of Mato Grosso, associated with phytophagous mites of the families Eriophyidae, Tenuipalpidae and Tetranychidae. The aim of this work was to compare the effect of different kinds of food, including different species of mites commonly found on the rubber tree in Mato Grosso, and one kind of pollen, on the oviposition of the predators Agistemus floridanus Gonzalez, 1965 (Stigmaeidae, Euseius concordis (Chant, 1959 and Neoseiulus anonymus (Chant & Baker, 1965, both Phytoseiidae. Those predators are common on rubber tree leaves in Mato Grosso. For the tests with A. floridanus, discs of 2 cm in diameter of rubber tree leaves were used as substrate. Food provided to the predators were the mites Calacarus heveae Feres, 1992, Oligonychus gossypii (Zacher, 1921, Polyphagotarsonemus latus (Banks, 1904, Tenuipalpus heveae Baker, 1945 and Tetranychus mexicanus (McGregor, 1950, and pollen of Typha angustifolia L. Agistemus floridanus accepted a larger variety of foodthan other predators. This was the only predator with high oviposition rate when fed C. heveae and T. heveae, the phytophagous mites considered most important on rubber trees. Euseius concordis and A. floridanus had nearly the same oviposition rates when fed pollen of T. angustifolia (ca. one egg per female per day. Neoseiulus anonymus had the highest oviposition rate than other predators when fed O. gossypii and T. mexicanus. Polyphagotarsonemus latus was the least suitable food for the predators studied.

  18. Efeitos do nim sobre tetranychus urticae Koch (Acari: Tetranychidae e os predadores Phytoseiulus macropilis (Banks e Neoseiulus californicus (Mcgregor (Acari: Phytoseiidae

    Directory of Open Access Journals (Sweden)

    Daniele Cristine Hoffmann Schlesener

    2013-03-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência de controle e os efeitos adversos de dois produtos à base de nim Azamax® (Azadiractina A/B 12g/L e Neemseto® (Azadiractina A/B, Nimbina e Salanina 2,389 g/L sobre o ácaro-rajado Tetranychus urticae e os predadores Phytoseiulus macropilis e Neoseiulus californicus em laboratório. Para o ácaro-rajado, foram consideradas as variáveis mortalidade, fecundidade, efeito ovicida e persistência biológica, enquanto para os fitoseídeos consideraram-se mortalidade e fecundidade. A mortalidade máxima observada para o ácaro-rajado foi de 89,7% e 91,5% para Azamax® e Neemseto®, respectivamente, na concentração de 0,5% após a reaplicação do produto no sétimo dia. Também foram observados efeitos adversos sobre a fecundidade e a viabilidade dos ovos quando tratados com os produtos comerciais (p.c.. A persistência biológica dos produtos foi de aproximadamente três dias após a pulverização. As formulações apresentaram seletividade em relação aos fitoseídeos, porém causaram redução da fecundidade dos mesmos.

  19. Morphological, molecular and cross-breeding analysis of geographic populations of coconut-mite associated predatory mites identified as Neoseiulus baraki: evidence for cryptic species?

    Science.gov (United States)

    Famah Sourassou, Nazer; Hanna, Rachid; Zannou, Ignace; Breeuwer, Johannes A J; de Moraes, Gilberto; Sabelis, Maurice W

    2012-05-01

    Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neoseiulus baraki Athias-Henriot, based on morphological similarity with regard to taxonomically relevant characters. However, scrutiny of our own and published descriptions suggests that consistent morphological differences may exist between the Benin population and those from the other geographic origins. In this study, we combined three methods to assess whether these populations belong to one species or a few distinct, yet closely related species. First, multivariate analysis of 32 morphological characters showed that the Benin population differed from the other three populations. Second, DNA sequence analysis based on the mitochondrial cytochrome oxidase subunit I (COI) showed the same difference between these populations. Third, cross-breeding between populations was unsuccessful in all combinations. These data provide evidence for the existence of cryptic species. Subsequent morphological research showed that the Benin population can be distinguished from the others by a new character (not included in the multivariate analysis), viz. the number of teeth on the fixed digit of the female chelicera.

  20. Failure of the mite-pathogenic fungus Neozygites tanajoae and the predatory mite Neoseiulus idaeus to control a population of the cassava green mite, Mononychellus tanajoa.

    Science.gov (United States)

    Elliot, Simon L; de Moraes, Gilberto J; Mumford, John D

    2008-12-01

    Monitoring of a population of the phytophagous cassava green mite, Mononychellus tanajoa (Bondar), and its natural enemies was undertaken in central Bahia, Brazil, in mid-1996. In spite of the presence of extremely high densities of the predatory phytoseiid mite Neoseiulus idaeus Denmark & Muma, the phytophagous mite population reached such high densities itself that there was total overexploitation of the cassava plants, leading to total leaf loss. Meanwhile, the mite-pathogenic fungus Neozygites tanajoae Delalibera, Humber & Hajek did not affect the M. tanajoa population in its growth phase as there was no inoculum present, even though we predict from a simple regression model that there was the potential for epizootics at that time. Soon after the M. tanajoa population crashed due to defoliation, there could have been an epizootic but there were simply no mite hosts to infect. These data demonstrate the ineffectiveness of one natural enemy (the predator) in terms of prey population regulation and demonstrate the importance of timing in the possible effectiveness of the other (the pathogen). For the pathogen, this probably explains its sporadic effect on host populations as previously reported. We conclude that the fungus is likely to be most useful as an adjunct to biological control with predatory mites other than N. idaeus.

  1. Life history of Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) fed with castor bean (Ricinus communis L.) pollen in laboratory conditions.

    Science.gov (United States)

    Marafeli, P P; Reis, P R; Silveira, E C da; Souza-Pimentel, G C; de Toledo, M A

    2014-08-01

    The predatory mite, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae)] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm) was 0.2 and the mean generation time (T) was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae.

  2. An entomopathogenic strain of Beauveria bassiana against Frankliniella occidentalis with no detrimental effect on the predatory mite Neoseiulus barkeri: evidence from laboratory bioassay and scanning electron microscopic observation.

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    Shengyong Wu

    Full Text Available Among 28 isolates of Beauveria bassiana tested for virulence against F. occidentalis in laboratory bioassays, we found strain SZ-26 as the most potent, causing 96% mortality in adults at 1×10(7 mL(-1conidia after 4 days. The effect of the strain SZ-26 on survival, longevity and fecundity of the predatory mite Neoseiulus (Amblyseius barkeri Hughes were studied under laboratory conditions. The bioassay results showed that the corrected mortalities were less than 4 and 8% at 10 days following inoculation of the adult and the larvae of the predator, respectively, with 1×10(7 conidia mL(-1 of SZ-26. Furthermore, no fungal hyphae were found in dead predators. The oviposition and postoviposition durations, longevity, and fecundity displayed no significant differences after inoculation with SZ-26 using first-instar larvae of F. occidentalis as prey in comparison with untreated predator. In contrast, the preoviposition durations were significantly longer. Observations with a scanning electron microscope, revealed that many conidia were attached to the cuticles of F. occidentalis at 2 h after treatment with germ tubes oriented toward cuticle at 24 h, penetration of the insect cuticle at 36 h, and finally, fungal colonization of the whole insect body at 60 h. In contrast, we never observed penetration of the predator's cuticle and conidia were shed gradually from the body, further demonstrating that B. bassiana strain SZ-26 show high toxicity against F. occidentalis but no pathogenicity to predatory mite.

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

    Science.gov (United States)

    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.

  4. Manejo integrado de pragas em macieira no Rio Grande do Sul II: uso de Neoseiulus californicus para o controle de Panonychus ulmi

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    MONTEIRO LINO B.

    2002-01-01

    Full Text Available Com o objetivo de implementar o controle biológico de ácaro-vermelho Panonychus ulmi em macieira foi proposta uma estratégia de controle baseada na criação de Neoseiulus californicus em estufa, em liberações inundativas e no uso de acaricidas, em um pomar comercial de macieira da Rincão das Flores Agropastoril (Agriflor, em Vacaria, Rio Grande do Sul, entre 1992 e 1996. A amostragem do ácaro-vermelho orientou as liberações e as transferências de ácaros predadores, das estufas de criação e dos ramos provenientes da poda verde, para parcelas de alta incidência de ácaro-vermelho. A eficiência da estratégia de controle do ácaro-vermelho foi avaliada com o levantamento de ovos de inverno. No primeiro ano, a associação de acaricidas com ácaros predadores permitiu um reduzido número de ovos de inverno do ácaro-vermelho, em torno de 1,3 ovo por unidade de amostragem contra 59,8 ovos na testemunha. No segundo ano, 58% das macieiras não foram pulverizadas com acaricidas. Nos dois anos subseqüentes, o controle do ácaro-vermelho foi realizado exclusivamente com ácaros predadores. N. californicus passou o inverno nas ervas daninhas do pomar e migrou espontaneamente para a copa das macieiras nos anos subseqüentes a sua introdução.

  5. Efeitos do nim sobre tetranychus urticae Koch (Acari: Tetranychidae e os predadores Phytoseiulus macropilis (Banks e Neoseiulus californicus (Mcgregor (Acari: Phytoseiidae Effects of neem on tetranychus urticae Koch (Acari: Tetranychidae and the predators Phytoseiulus macropilis (Banks and Neoseiulus Californicus (Mcgregor (Acari: phytoseiidae

    Directory of Open Access Journals (Sweden)

    Daniele Cristine Hoffmann Schlesener

    2013-03-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência de controle e os efeitos adversos de dois produtos à base de nim Azamax® (Azadiractina A/B 12g/L e Neemseto® (Azadiractina A/B, Nimbina e Salanina 2,389 g/L sobre o ácaro-rajado Tetranychus urticae e os predadores Phytoseiulus macropilis e Neoseiulus californicus em laboratório. Para o ácaro-rajado, foram consideradas as variáveis mortalidade, fecundidade, efeito ovicida e persistência biológica, enquanto para os fitoseídeos consideraram-se mortalidade e fecundidade. A mortalidade máxima observada para o ácaro-rajado foi de 89,7% e 91,5% para Azamax® e Neemseto®, respectivamente, na concentração de 0,5% após a reaplicação do produto no sétimo dia. Também foram observados efeitos adversos sobre a fecundidade e a viabilidade dos ovos quando tratados com os produtos comerciais (p.c.. A persistência biológica dos produtos foi de aproximadamente três dias após a pulverização. As formulações apresentaram seletividade em relação aos fitoseídeos, porém causaram redução da fecundidade dos mesmos.The aim of the present study was to evaluate the efficiency of control and adverse effects of two neem based products: Azamax TM (Azadirachtin A/B 12g/L and Neemseto TM (Azadirachtin A/B, Nimbin and Salanin 2,389 g/L over two-spotted spider mite Tetranychus urticae and the predators Phytoseiulus macropilis and Neoseiulus californicus in laboratory. Effects over the mortality, fecundity, eggs and biological persistence of the two-spotted spider mite when treated with neem based products were evaluated. For the phytoseiids the effects on mortality and fecundity were evaluated. The maximum mortality of two-spotted spider mites rates observed were 89.7% and 91.5% for Azamax TM and Neemseto TM respectively, on the 0.5% concentration after reapplying the product on the seventh day. Adverse effects were also observed over the fecundity and viability of the eggs when treated with

  6. Seletividade de alguns agrotóxicos em uso na citricultura ao ácaro predador Neoseiulus californicus (McGregor (Acari: Phytoseiidae Residual toxicity of the main pesticides recommended in citrus orchards on predaceous mite Neoseiulus californicus (Mcgregor (Acari: Phytoseiidae

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    Marcos Zatti da Silva

    2006-08-01

    Full Text Available Objetivou-se avaliar o efeito dos principais agrotóxicos utilizados em citros sobre Neoseiulus californicus (McGregor, em condições de laboratório, por tratar-se de um fitoseídeo com grande potencialidade para ser utilizado no controle dos ácaros fitófagos na cultura. O método de bioensaio adotado foi o de contato direto e residual. Folhas de citros da variedade Pêra, contendo 25 fêmeas adultas de N. californicus procedentes de uma criação-estoque, foram pulverizadas em torre de Potter. Avaliaram-se a mortalidade do ácaro 72 horas após a aplicação e o efeito dos produtos na viabilidade dos ovos. Quanto à seletividade, conforme proposta da "Organização Internacional para o Controle Biológico e Integrado de Plantas e Animais Nocivos" (IOBC, os produtos foram classificados como: classe 1 inócuo (E99%, clorfenapyr, dicofol e pyridaben. N. californicus mostrou-se tolerante a diversos agrotóxicos, o que viabiliza sua utilização, juntamente com produtos químicos pertencentes a grupamentos distintos e de diferentes mecanismos de ação, o que atende a um manejo adequado de controle dos principais ácaros fitófagos da cultura dos citros.This work was carried out to determine the residual toxicity of the main pesticides used in citrus, on Neoseiulus californicus (McGregor under laboratory conditions. For this, it was used the residual contact bioassay. Citrus leaves of the variety "Pêra" were sprayed in a Potter tower. The residual action was evaluated at 2 hours and 1; 3; 5; 7; 10; 14 e 21 days after treatment. Ten adult females of N. californicus were transferred to each ring, together with an enough amount of Tetranychus urticae nymphs and adults to feed the predator. Mortality evaluations were performed at 72 hours after treatment. Bioassays indicate that the pesticides: acrinathrin, deltamethrin, dinocap, sulphur, fenpropathrin, fenbutatin oxide and propargite were innocuous to N. californicus. On the other hand, abamectin

  7. Acute toxicity of four insecticides against adult mite of Neoseiulus cucumeris (Oudemans)%4种杀虫剂对胡瓜钝绥螨成螨的急性毒性

    Institute of Scientific and Technical Information of China (English)

    陈霞; 张艳璇; 季洁; 林坚贞

    2007-01-01

    测定了4种常用杀虫剂针对目标害虫推荐使用浓度范围对天敌胡瓜钝绥螨Neoseiulus cucumeris成螨的毒力测定、综合急性毒性和二次中毒毒性.综合急性毒性和二次中毒毒性测定结果显示,毒死蜱Chlorphifos、灭幼脲Chlorbenzurin、吡虫啉Imidacloprid对胡瓜钝绥螨都具有极强的毒性,可造成毁灭性杀伤,苏云金杆菌Bt对胡瓜钝绥螨影响极小,无明显毒性.玻片浸渍法测定的不同杀虫剂对胡瓜钝绥螨的毒力大小依次为:毒死蜱Chlorphifos(乐斯本)>灭幼脲Chlorbenzurin>吡虫啉Imidacloprid>苏云金杆菌Bt.

  8. Effects of Six Different Pollens on Development and Reproduction of Neoseiulus californicus%6种花粉对加州新小绥螨发育繁殖的影响

    Institute of Scientific and Technical Information of China (English)

    袁秀萍; 任俊; 王小军; 赵伊英

    2016-01-01

    为探讨不同花粉对加州新小绥螨Neoseiulus californicus (McGregor)发育和繁殖的影响,在室内采用油菜(Brassica campestris)、槐花(Sophora japonica)、向日葵(Helianthus annuus)、南瓜(Cucurbita moschata)、玉米(Zea mays)和棉花(Gossypium hirstutum)6种植物的花粉分别饲喂加州新小绥螨,观察加州新小绥螨雌成螨繁殖、幼螨发育历期及各螨态存活率.结果表明,经向日葵花粉饲喂后,加州新小绥螨雌成螨存活时间为28.33 d,单雌产卵量最高为32.23粒,幼螨发育为成螨最短需5.84 d,其净增值率(R0)和内禀增长力(rm)分别为29.61和0.18;与其他花粉相比,向日葵花粉的饲喂结果更接近与土耳其斯坦叶螨(Tetranychus turkestani)饲喂的结果.可见向日葵花粉有利于加州新小绥螨繁殖.饲喂不同花粉后,加州新小绥螨的卵期和幼螨期无显著差异,说明花粉主要影响若螨和成螨,对卵和幼螨影响较小.

  9. 温度对加州新小绥螨捕食作用影响及高温耐饥饿能力研究%Effect of Temperature on Predation of Neoseiulus californicus (McGregor) and Starvation Tolerance at High Temperature

    Institute of Scientific and Technical Information of China (English)

    覃贵勇; 李庆

    2013-01-01

    The functional responses of Neoseiulus californicus (McGregor) to Panonychus citri AaGregor at different temperatures and the starvation tolerance at high temperature of N.californicus and other four predatory mites were studied.The result showed that the controlling effect of N.californicus to P.citri AaGregor increased with the experimental temperature range of 20 to 30 ℃,the controlling effect was the strongest at 30 ℃,but when the temperatures was higher than 34 ℃,the controlling effect decreased ; the starvation tolerance at high temperature of N.californicus was higher than that of Amblyseius eharai Amitai et Swirski and Euseius nicholsi,and closed to that of A.pseudolongispinosus and A.makuwa Ehara.%本文研究了在不同温度条件下加州新小绥螨Neoseiulus californicus(McGregor)对柑橘全爪螨Panonychus citri AaGregor的功能反应,以及研究了加州新小绥螨等5种捕食螨的高温耐饥饿能力.结果表明:在20~30℃温度下,随着温度的升高,加州新小绥螨对柑橘全爪螨各螨态的控制能力增强,在30℃时,控制能力最强,而超过30 ℃时,加州新小绥螨的控制能力下降;加州新小绥螨的高温耐饥饿能力显著高于江原钝绥螨Amblyseius eharai Amitai et Swirski和尼氏真绥螨Euseius nicholsi(Ehara et Lee),而与拟长毛钝绥螨A.pseudolongispinosus和真桑钝绥螨A.makuwa Ehara接近.

  10. The effect of repeated release of the predatory mite Neoseiulus (Amblyseius) cucumeris on arthropod communities in citrus ecosystems%多次释放胡瓜新小绥螨对橘园节肢动物群落多样性的影响

    Institute of Scientific and Technical Information of China (English)

    季洁; 张艳璇; 陈霞; 林坚贞; 孙莉

    2012-01-01

    为了探明长期多次释放胡瓜新小绥螨(Neoseiulus (Amblyseius) cucumeris)是否会对橘园节肢动物群落的生物多样性产生影响,我们在福州马尾和晋安试验区的2个橘园分别设置生防园、自然园和化防园,连续两年每月两次在各处理橘园的树冠和地面杂草中采集并记录节肢动物的种类和数量,结果表明两个试验区的物种丰富度(S)均以生防园最高,且都显著高于相应的化防园和自然园;马尾试验区三种处理的多样性指数(H)和均匀度指数(E)的大小依次为生防园>自然园>化防园,晋安试验区则为自然园>生防园>化防园,表明释放胡瓜新小绥螨防治柑橘害螨,减少农药的使用,能恢复或增加橘园节肢动物群落的生物多样性.此外,释放胡瓜新小绥螨未对橘园原有的捕食螨类群产生影响.%In order to study the effect of repeated release of Neoseiulus {Amblyseius) cucumeris on the species composition and diversity of arthropod community in citrus ecosystems, we established bio-control orchards, natural orchards and chemical control orchards in the Mawei and Jin'an experimental field of Fuzhou, China. Our results indicated that the species richness of bio-control orchards was higher than that of natural or chemical control orchards at both sites. Diversity and evenness indices were higher in bio-control orchards than those of other orchards in the Mawei site, and those of chemical control orchards were the lowest. Among the variously managed orchards in Jin'an, evenness and diversity indices were highest in the natural orchards and lowest in chemical orchards. Our study suggests that citrus ecosystem arthropod diversity can be enhanced by releasing N. cucumeris to fight against the citrus pest mites while reducing the spraying of pesticide.

  11. 阿维菌素亚致死剂量对虚伪新小绥螨的影响%Sublethal Effects of Abamectin on the Biological Performance ofNeoseiulus fallacis (Garman)

    Institute of Scientific and Technical Information of China (English)

    宋子伟; 张宝鑫; 邓彩凤; 李敦松

    2014-01-01

    Abamectin is one of the most popular pesticide and acaricide. In this study, the sublethal effects of abamectin on the biological performance of the predator mites,Neoseiulus fallacis (Garman), was assessed in laboratory conditions by the life table. The female adults ofN. fallacis were exposed to the sublethal concentration abamectin (LC30, LC20and LC10), fecundity per female were 29.11, 34.25 and 45.81, and fecundity per female per day ofN. fallacis were 0.73, 0.99 and 1.50. Fecundity per female of LC20and LC30were significantly different with CK (53.89), fecundity per female per day of all the three treatments was significantly different with CK (2.43), but the sex ratio of offspring was not affected by the abamectin. In treatment by abamectin, pre-oviposition period of the next generation was longer, oviposition and post-oviposition period was shorter than the control, but female longevity was not different from the control. With treatment by abamectin, the net reproductive rate (R0) and intrinsic rate of increase (rm) were declined, mean generation time (T) and doubling time (Dt) were increased. Analysis showed that the survival time of nearly 40% individuals treated by LC10and LC30 were longer than CK, and the life expectancy of offspring treated by LC10and LC30 were significantly higher than CK. In conclusion, thesublethal concentration of abamectin was adverse to the fecundity ofN. fallacis, but there was no significant effect to the development ofN. fallacis.%阿维菌素是目前常用的杀虫杀螨剂。本研究利用生命表技术,室内评价了阿维菌素亚致死剂量对虚伪新小绥螨成螨生长发育及生殖的影响。通过阿维菌素亚致死剂量(LC30、LC20和LC10)处理虚伪新小绥螨成螨后,平均每雌产卵量分别为29.11、34.25、45.81粒;每雌日均产卵量分别为0.73、0.99、1.50粒,平均每雌产卵量LC20和LC30与对照(53.89粒)有显著差别,每雌日均产卵量3个处理与对照(2

  12. Starvation Tolerance of Neoseiulus barkeri and Euseius nicholsi and the Influence of Starvation on Predation Function of Their Female Adults%巴氏新小绥螨和尼氏真绥螨的耐饥能力及饥饿对其雌成螨捕食作用的影响

    Institute of Scientific and Technical Information of China (English)

    罗育发; 钟八莲

    2012-01-01

    室内测定巴氏新小绥螨Neoseiulus barkeri Hughes和尼氏真绥螨Euseius nicholsi Ehara et Lee的耐饥饿能力,并分析了饥饿程度对两种捕食螨雌成螨捕食朱砂叶螨Tetranychus cinnabarinus Boisduval若螨的功能反应和捕食速度的影响.结果表明:两种捕食螨各螨态的耐饥时间与发育历期呈显著正相关(P<0.05),巴氏新小绥螨的耐饥能力明显强于尼氏真绥螨;不同饥饿程度的两种捕食螨雌成螨捕食朱砂叶螨若螨的功能反应均为霍林-Ⅱ型,饥饿程度虽不能改变它们的捕食功能反应类型,但可使功能反应模型的各参数值发生较大改变;饥饿24小时的巴氏新小绥螨和尼氏真绥螨雌成螨在取食朱砂叶螨若螨的24小时内,其捕食作用主要集中在前8小时阶段,未经饥饿处理的两种捕食螨雌成螨捕食速度在24小时内各阶段的差异不大.%Laboratory experiments were conducted to study the tolerance of Neoseitdus barkeri HugHes and Euseius nicholsi Ehara et Lee to starvation and the influence of starvation on predation of female adults of the two predatory mites on nymphs of Tetranychus cinnabarinus BoisduvaL Results showed that the survival time of the starving instars of N. Barkeri and E. Nicholsi was significantly positively related with their instar age (P<0. 05). The starvation tolerance of N. Barkeri was obviously stronger than that of E. Nicholsi. The functional responses of female adults of N. Barkeri and E. Nicholsi at various levels of starvation to nymphs of T. Cinnabarinus were fitted to Holling II -types. Starvation duration did not alter the functional response types of female adults of the two predatory mites, but greatly changed the parameters of the functional response mode. The predation on nymphs of T. Cinnabarinus of female adults N. Barkeri and E. Nicholsi after starved for 24 hours was concentrated in the first 8 hours of feeding, whereas no apparent variation in thepredation of the female

  13. 巴氏新小绥螨的新特性——捕食植物线虫及其发育繁殖%The Predatory Mite Neoseiulus barkeri (Acari: PhytoseUdae), a New Biocontrol Approach for Plant-parasitic Nematode, and Associated Development and Reproduction

    Institute of Scientific and Technical Information of China (English)

    周万琴; 徐春玲; 徐学农; 张宝鑫; 秦厚国; 王恩东; 李敦松; 谢辉

    2012-01-01

    在实验室条件下评价了巴氏新小绥螨捕食南方根结线虫时的发育和繁殖情况,观察了其捕食行为,并测定了其对几种线虫的捕食量。该螨对线虫的捕食行为可分为猎物的寻找、固定、捕食、清理和静息等步骤,对水稻干尖线虫和南方根结线虫二龄幼虫(Mi-J2)的捕食量显著大于对虫体较大和活动性较强的腐烂茎线虫和自由生活的小杆线虫的捕食量;每头雌螨日捕食Mi-J2不少于25条。以Mi-J2为食的巴氏新小绥螨能发育完成生活史,并具有较强的繁殖能力,其卵期、幼螨期、前若螨期、后若螨期、产卵期、雌螨寿命、平均每头雌螨产卵量和日均产卵量分别为1.1d、0.71d、2.06d、1.98d、22-31d、35.13d、41.08粒和1.85粒,其内禀增长率、周限增长率均大于以腐食酪螨为食的巴氏新小绥螨,而平均世代周期和种群倍增时间均小于后者。%Predatory behavior, development and reproduction of Neoseiulus barkeri (Hughes) on plant-parasitic nematodes Meloidogyne incognita, Aphelenchoides besseyi, Ditylenchus destructor and free living nematode Rhabditis sp. were evaluated under laboratory conditions. The behavior components of the predatory mite preying on nematode included searching, prey-fixing and feeding, chelecera-and-palp-clearing and resting. N. barkeri did not always consume a whole nematode. Residues of nematodes were sometimes found on agar surface. The number of live nematodes consumed was much more than dead ones. A. besseyi and second-stage juveniles of M. incognita (Mi-J2) were preferred to D. destructor and Rhabditis sp., the later were larger and more active. N. barkeri was able to complete its life cycle on Mi-J2, and the average duration of egg, larva, protonymph, deutonymph, oviposition and female adult longevity were 1.1, 0.17, 2.06, 1.98, 22.31 and 35.13 days, respectively, and the daily consumption of Mi-J2 by a female mite was no

  14. Compatibility of Beauveria bassiana with Neoseiulus barkeri for Control of Frankliniella occidentalis

    Institute of Scientific and Technical Information of China (English)

    WU Sheng-yong; GAO Yu-lin; XU Xue-nong; Mark S Goettel; LEI Zhong-ren

    2015-01-01

    The entomopathogenic fungusBeauveriabassiana (Balsamo) Vuilemin and predatory miteNeoseiulusbarkeri Hughes are effective biological control agents ofFranklinielaoccidentalis Pergande (Thysanoptera: Thripidae), one of the most important pests of ornamentals and vegetables world-wide. Combined application of both may enhance control efifciency. The functional response forN.barkeri on the ifrst instar larvae of western lfower thrips which were infected byB.bassiana for 12 and 24 h in the laboratory ((25±1)°C, (70±5)% RH, L:D=16 h:8 h) was determined. The virulence ofB.bassiana against the second instar and pupae of the thrips attacked byN.barkeri were also tested. The results showed that N.barkeri exhibited a Holing type II functional response on treated thrips. After having been treated with the fungus for 12 h and then offered to the predator, thrips were more vulnerable to be kiled byN.barkeri. The second instar larvae and pupae of the thrips which had been attacked by predatory mites were markedly more susceptible toB.bassiana infection than normal thrips; the cumulative corrected mortality ofB.bassiana of the second instar and pupae which were attacked byN.barkeri were 57 and 94%, respectively, compared to 35 and 80% in controls on the day 8. These ifndings highlight the potential use ofB.bassiana in combination withN.barkeri to controlF. occidentalis.

  15. Predatory behaviors of Neoseiulus californicus and Galendromus helveolus (Acari: Phytoseiidae) attacking Oligonychus perseae (Acari: Tetranychidae).

    Science.gov (United States)

    Takano-Lee, M; Hoddle, Mark

    2002-01-01

    Predatory behaviors of Neosieulus californicus (McGregor) and Galendromus helveolus (Chant) attacking Oligonychus perseae Tuttle, Baker and Abbatiello on avocado leaves were videotaped and analyzed. Behaviors were recorded for "fresh" predators that were used perseae only after invading webbed nests. Conversely. fresh and cold stored N. californicus employed three different modes of predatory attack: (1) intercepting and attacking migrant O. perseae outside of web nests: (2) attacking prey through nest webbing; or (3) invading and attacking O. perseae inside nests. Predatory efficacy of both N. californicus and G. helveolus was reduced following cold storage. as both species engaged in certain predatory behaviors less frequently in comparison to predators that were not stored at low temperatures. Our observed results for N. californicus and G. helveolus attacking O. perseae are interpreted in relation to the chaetotaxy hypothesis, which proposes that phytoseiid invasion efficiency and propensity of webbed nests is facilitated by dorsal setal lengths.

  16. Toxicidade diferencial de agrotóxicos utilizados em citros para Neoseiulus californicus, Euseius concordis e Brevipalpus phoenicis

    Directory of Open Access Journals (Sweden)

    Marcos Zatti da Silva

    2011-01-01

    Full Text Available Brevipalpus phoenicis (Geijskes (Acari: Tenuipalpidae é considerada uma das principais pragas em citros no Brasil, devido à transmissão do vírus da leprose dos citros e à necessidade de frequentes aplicações de acaricidas para seu controle. Assim, objetivou-se comparar a toxicidade dos principais agrotóxicos utilizados em citros no Brasil, sobre populações de B. phoenicis e de ácaros predadores das espécies Neoseiuluscalifornicus (McGregor e Euseius concordis (Chant (Acari: Phytoseiidae. Foram avaliadas duas populações de E. concordis: uma procedente de Jaboticabal (SP e outra de Descalvado (SP. Arenas de folhas (para fitoseídeos ou frutos (para B. phoenicis de Citrus sinensis Osbeck (L. cv. Pera, contendo 25 fêmeas adultas de cada espécie foram pulverizadas em torre de Potter. As avaliações de mortalidade foram realizadas 72 horas após a aplicação. Foram utilizadas 4 a 6 concentrações de cada produto (abamectina, acefato, azociclotina, bifentrina, clorfenapir, dicofol, dinocape, óxido de fembutatina, propargito e piridabem para a obtenção das curvas de concentração-resposta. Abamectina, azociclotina, clorfenapir, dicofol, dinocape, óxido de fembutatin, propargito e piridabem foram altamente tóxicos a B. phoenicis, com valores de CL90 iguais ou inferiores aos das concentrações recomendadas desses produtos. N. californicus foi mais tolerante a bifentrina, propargito, óxido de fembutatina e dinocape que B. phoenicis e E. concordis (ambas as populações. Esses acaricidas tiveram baixa toxicidade aos adultos de N. californicus, para o qual as CL50 foram pelo menos seis vezes maiores que suas concentrações recomendadas. Acefato foi extremamente tóxico a E. concordis, mas inócuo a adultos de N. californicus. A população de E. concordis de Jaboticabal foi mais resistente que a de Descalvado a azociclotina, bifentrina, clorfenapir, dicofol e propargito.

  17. Morphological, molecular and cross-breeding analysis of geographic populations of coconut-mite associated predatory mites identified as Neoseiulus baraki: evidence for cryptic species?

    NARCIS (Netherlands)

    N.F. Sourassou; R. Hanna; I. Zannou; J.A.J. Breeuwer; G. de Moraes; M.W. Sabelis

    2012-01-01

    Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neosei

  18. A revision of the Malesian species op Palmeria (Monimiaceae—Monimieae)

    NARCIS (Netherlands)

    Philipson, W.R.

    1982-01-01

    Twelve species are recognized of which five (P. womersleyi, P. brassii, P. hooglandii, P. schoddei. and P. clemensae) are described as new. Nine species are reduced to synonymy (P. warburgii, P. puberula, P. myriantha, P. paniculata, P. parvifolia, P. acuminata, P. habbamensis, P. pulchra and P. dal

  19. A revision of the Malesian species op Palmeria (Monimiaceae—Monimieae)

    NARCIS (Netherlands)

    Philipson, W.R.

    1982-01-01

    Twelve species are recognized of which five (P. womersleyi, P. brassii, P. hooglandii, P. schoddei. and P. clemensae) are described as new. Nine species are reduced to synonymy (P. warburgii, P. puberula, P. myriantha, P. paniculata, P. parvifolia, P. acuminata, P. habbamensis, P. pulchra and P.

  20. Criterios para el manejo de Tetranychus urticae Koch (Acari: Tetranychidae con el ácaro depredador Amblyseius (Neoseiulus sp. (Acari: Phytoseiidae en cultivos de rosas

    Directory of Open Access Journals (Sweden)

    Forero Gabriel

    2008-04-01

    Full Text Available

    En cultivos de rosas en la Sabana de Bogotá, se ha registrado Amblyseius sp. como un ácaro depredador de Tetranychus urticae. Con el fin de evaluar el potencial de este ácaro en el manejo de T. urticae, se comparó en cultivos comerciales de rosa, bajo el sistema de agobio, la efectividad de liberaciones de Amblyseius sp. frente a la aplicación de productos de síntesis química, teniendo en cuenta los siguientes criterios de evaluación: presencia-ausencia del ácaro fitófago, porcentaje de daño causado en hojas y tipo de foco de T. urticae. Además, se evaluó la presencia del ácaro depredador ocho días después de las liberaciones. Se realizaron ensayos de respuesta funcional con densidades crecientes en los tres estados de desarrollo: huevo, larva o ninfas de la presa, bajo condiciones controladas y de invernadero. Se encontró menor cantidad (19,4% de ácaros fitófagos con la aplicación de productos químicos. Sin embargo, el porcentaje de daño en la hoja fue menor (índice de daño 1 y 3, 8% y 13% menos, respectivamente con las liberaciones de Amblyseius sp. Se evidenciaron diferencias en el tipo de foco para ambas estrategias de manejo y se registró una presencia semanal promedio del 23% para el ácaro depredador. La capacidad de consumo (respuesta funcional a las 24 horas por parte de Amblyseius sp. fue de 6,66 huevos, 18,06 larvas y 19,15 ninfas bajo condiciones controladas, y de 4,56 huevos, 12,65 larvas y 15,71 ninfas bajo invernadero.

  1. 巴氏新小绥螨对相似穿孔线虫的捕食作用及在植物上的分布%On Predatory Ability of Neoseiulus Barkeri on Radopholus Similis and Its Distribution on Plant

    Institute of Scientific and Technical Information of China (English)

    周万琴; 谢辉; 李敦松; 王恩东; 张宝鑫; 徐春玲

    2016-01-01

    在实验室条件下评价了巴氏新小绥螨对相似穿孔线虫的捕食作用,并通过盆栽接种研究了其在植株和根际的垂直分布情况.结果表明,巴氏新小绥螨能够取食线虫,每头雌成螨平均每天捕食相似穿孔线虫49.50头;在盆栽茄子根际释放巴氏新小绥螨10 d,20 d和30 d后,在根际土壤、表层土壤和地上植株均有分布,在10d时分布在这3个位置的数量差异不明显,但随着释放时间的延长,可能由于土壤中缺乏食物,根际土壤中分布数量显著少于植物地上部分.

  2. Population dynamics of thrips prey and their mite predators in a refuge

    NARCIS (Netherlands)

    Magalhães, S.; Van Rijn, P.C.J.; Montserrat, M.; Pallini, A.; Sabelis, M.W.

    2007-01-01

    Prey refuges are expected to affect population dynamics, but direct experimental tests of this hypothesis are scarce. Larvae of western flower thrips Frankliniella occidentalis use the web produced by spider mites as a refuge from predation by the predatory mite Neoseiulus cucumeris. Thrips incur a

  3. Verified and potential pathogens of predatory mites (Acari: Phytoseiidae)

    NARCIS (Netherlands)

    Schütte, C.; Dicke, M.

    2008-01-01

    Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator¿prey inter

  4. Insight into the feeding behavior of predatory mites on Beauveria bassiana, an arthropod pathogen.

    Science.gov (United States)

    Wu, Shengyong; Zhang, Ye; Xu, Xuenong; Lei, Zhongren

    2016-04-04

    Interactions between fungal entomopathogens and pest predators are particularly relevant in control of agricultural insect pests. In a laboratory study, we confirmed that the predatory mite, Neoseiulus barkeri, exhibited feeding behavior on the entomopathogenic fungus Beauveria bassiana conidia through DNA extracts. Using transmission electron microscopy, we determined that the majority of conidia found in the mite gut tended to dissolve within 24 h post ingestion, suggesting that the conidia had probably lost their viability. To our knowledge this is the first report of feeding behavior of phytoseiid mites on entomopathogenic fungus. The findings expand our knowledge of fungus-predator interactions.

  5. Ácaros predadores e o fungo Neozygites floridana associados a tetraniquídeos em soja no Rio Grande do Sul Predatory mites and the fungus Neozygites floridana associated with spider mites on soybean, in Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Samuel Roggia

    2009-01-01

    Full Text Available O objetivo deste trabalho foi verificar a ocorrência de ácaros predadores e do fungo Neozygites floridana, associados a ácaros tetraniquídeos, em soja (Glycine max L., no Estado do Rio Grande do Sul. Entre 2003 e 2005, foram avaliadas amostras de folhas de soja das principais regiões produtoras do Estado. Essas amostras foram coletadas de diferentes posições da planta e aleatoriamente na lavoura. As espécies de ácaros predadores encontradas foram: Neoseiulus anonymus, N. californicus, Phytoseiulus fragariae, P. macropilis, Proprioseiopsis cannaensis e Galendromus annectens. O fungo N. floridana apresentou ampla distribuição e ocorreu em todas as espécies de tetraniquídeos encontradas: Mononychellus planki, Tetranychus desertorum, T. gigas, T. ludeni e T. urticae.The objective of this work was to verify the occurrence of predatory mites and the fungus Neozygites floridana, associated with spider mites in soybean (Glycine max L., in Rio Grande do Sul, Brazil. From 2003 to 2005, samples of soybean leaves from the most important soybean producing regions of the state were evaluated. These samples were collected from different positions of the plant and randomly in the field. The predatory mite species found were Neoseiulus anonymus, N. californicus, Phytoseiulus fragariae, P. macropilis, Proprioseiopsis cannaensis, and Galendromus annectens. The fungus N. floridana was widely distributed and occurred in all the spider mite species found: Mononychellus planki, Tetranychus desertorum, T. gigas, T. ludeni and T. urticae.

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

    Science.gov (United States)

    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.

  7. Phytoseiid mites (Acari: Phytoseiidae) from Patagonia and Tierra del Fuego.

    Science.gov (United States)

    Ferragut, Francisco; Navia, Denise

    2015-07-28

    Predatory phytoseiid mites have been intensively studied and surveyed in the last decades because of their economic importance as biocontrol agents of agricultural pests. However, many regions of the world remain unexplored and the diversity of the family worldwide is still fragmentary. Up to date no phytoseiid species have been collected in the southernmost part of the Earth down to latitude 45º S. In this study Phytoseiidae were sampled from native vegetation in southern Argentina and Chile in the regions of Patagonia and Tierra del Fuego Island. Thirteen species were collected, five of which were previously described and eight, Chileseius australis n. sp., Neoseiulus mapuche n. sp., Typhlodromips valdivianus n. sp., T. fissuratus n. sp., Amblyseius grandiporus n. sp., A. caliginosus n. sp., Typhlodromus (Anthoseius) anomalos n. sp. and Metaseiulus parabrevicollis n. sp. are proposed as new to science and are described and diagnosed.

  8. Female performance towards offspring under starved conditions in four phytoseiid species (Acari, Phytoseiidae).

    Science.gov (United States)

    Zhang, Yanxuan; Ji, Jie; Lin, Jianzhen; Chen, Xia; Saito, Yutaka

    2015-01-01

    There is an important difference between cannibalism between unrelated individuals and between a mother and its offspring, because the former can be defined as a form of intraspecific competition, but the latter affects the inclusive fitness of individuals. Many examples of cannibalism have been reported in predacious phytoseiid mites. Furthermore, sib cannibalism avoidance is known in several species. However, whether females' actually prey upon their offspring under starved conditions has yet to be established. Here, female performance towards their offspring under no-prey-other-than-offspring, water-available and humidity-selectable conditions, was observed in four phytoseiid species, Amblyseius eharai, Amblyseius swirskii, Neoseiulus cucumeris and Typhlodromus bambusae. Typhlodromus bambusae females only survived for 4.14 ± 0.42 days and there was a significant difference in survival duration between T. bambusae and the other three species (all survived more than 8 days). Neoseiulus cucumeris females survived longer than A. eharai and A. swirskii females, whereas there was no difference between A. eharai and A. swirskii females. On the other hand, the offspring (immature stages from egg to larva or protonymph) of A. eharai, A. swirskii and N. cucumeris died earlier in mother-presence than in mother-absence (egg alone) experiments, suggesting that cannibalistic interactions occur between mother and offspring. The survivorship of T. bambusae offspring in the mother-presence condition did not differ from the mother-absence condition, indicating that kin cannibalism is rare in this species. This must be related to the phenomenon that mothers tend to die before their offspring. The short longevity of T. bambusae mothers is one of the reasons why there is no significant difference in immature survival between the mother-presence and mother-absence experiments. Lastly, the reason(s) behind such variation in female phytoseiid performance towards their offspring is

  9. Comparação econômica entre controle biológico e químico para o manejo de ácaro-vermelho em macieira Economic comparison of biological and chemical control in the management of red spider mites in apple orchard

    Directory of Open Access Journals (Sweden)

    Lino Bittencourt Monteiro

    2006-12-01

    Full Text Available O ácaro-vermelho da macieira, Panonychus ulmi (Acari: Tetranychidae, é uma importante praga na cultura da macieira em Fraiburgo - SC, e o controle biológico aplicado foi implantado em meados dos anos 90. O objetivo deste trabalho foi demonstrar os benefícios econômicos da utilização do controle biológico no manejo do ácaro-vermelho. A avaliação foi realizada em dois pomares comerciais de macieiras. Em um deles, foi implantado o controle biológico aplicado de ácaros, baseado na liberação do ácaro predador Neoseiulus californicus (Acari: Phytoseiidae, seleção de inseticidas e manejo de ervas invasoras, e o outro pomar seguiu o manejo convencional de artrópodes, baseado na aplicação de produtos químicos para o controle de insetos, ácaros fitófagos e ervas invasoras. A análise econômica mostrou que os custos com mão-de-obra e máquinas foram semelhantes em ambos os pomares, entretanto os custos com acaricidas foram significativamente inferiores no pomar onde o manejo foi o controle biológico, demonstrando que, apesar da necessidade de investimentos em instalações para a criação do ácaro predador e custos de manutenção das mesmas, a estratégia biológica foi economicamente viável.Red spider mite, Panonychus ulmi (Acari: Tetranychidae is a significant pest in apple tree in Fraiburgo, Santa Catarina (SC and applied biological control was implemented in the mid-nineties. The objective of this study was to demonstrate the economic benefits of biological control in the management of red spider mite. The assessment was carried out in two commercial orchards, one of which was subjected to biological control of spider mite by releasing the predator Neoseiulus californicus, insecticide selection and weed management, and the other to conventional arthropod management, based on the application of chemicals to control insects, phytofagous mites and weed. Economic analysis showed that the costs for labor and machines were

  10. Winter annual cover crop has only minor effects on major corn arthropod pests.

    Science.gov (United States)

    Davis, Holly N; Currie, Randall S; Klocke, Norman L; Buschman, Lawrent L

    2010-04-01

    We studied the effects of downy brome, Bromus tectorum L., winter cover crop on several corn, Zea mays L., pests in the summer crop after the cover crop. An experiment was conducted that consisted of two trials with two levels of irrigation, two levels of weed control, and two levels of downy brome. Corn was grown three consecutive years after the downy brome grown during the winter. Banks grass mites, Oligonychus pratensis (Banks), twospotted spider mites, Tetranychus urticae Koch, and predatory mites from the genus Neoseiulus were present in downy brome at the beginning of the growing season. They moved into corn, but their numbers did not differ significantly across the treatments. Larval western corn rootworm, Diabrotica virgifera virgifera LeConte, feeding on corn roots was evaluated the second and third years of corn, production. Irrigation and herbicide treatments had no significant effects on rootworm injury levels. In one trial, rootworm injury ratings were significantly greater in treatments with a history of high versus low brome, but this effect was not significant in the other trial. Rootworm injury seemed to be similar across plots with different surface soil moistures. This suggests that the use of a winter cover crop such as downy brome will not have a major negative impact the arthropods studied.

  11. Importance of ambient saturation deficits in an epizootic of the fungus Neozygites floridana in cassava green mites (Mononychellus tanajoa).

    Science.gov (United States)

    Elliot, Sam L; De Moraes, Gilberto J; Mumford, John D

    2002-01-01

    The mite-pathogenic fungus Neozygites floridana Fisher (Entomophthorales: Neozygitaceae) is considered to have potential for the biological control of the cassava green mite, Mononychellus tanajoa (Bondar). However, its activity is sporadic and laboratory data suggest a strong dependence on night-time saturation deficits for transmission. We report on an epizootic of this fungus in a mite population in northeastern Brazil. During the epizootic, host populations appeared to he limited by a combination of the pathogen and a predatory mite Neoseiulus idaeus (Acari: Phytoseiidae). When temperatures increased, the epizootic finished and the host population began to grow. Abiotic conditions could not explain the variation in host mortality following pickup of infective propagules in this epizootic. However, night-time saturation did help to explain the variation in transmission from infective cadavers to newly killed hosts. This supports laboratory observations that horizontal transmission between hosts is determined mainly by saturation deficits, while the process of infection is little affected by abiotic conditions. A further field observation was the near-absence of resting spores in dead mites (ca. 0.1% of cadavers), suggesting that the pathogen population was unsuccessful in producing inoculum to infect future M. tanajoa populations. The implications are that this pathogen will only be effective as a biological control agent in periods of high relative humidity, and establishment in new areas may be limited by resting spore formation.

  12. Potential of the mite-pathogenic fungus Neozygites floridana (Entomophthorales: Neozygitaceae) for control of the cassava green mite Mononychellus tanajoa (Acari: Tetranychidae).

    Science.gov (United States)

    Elliot, S L; de Moraes, G J; Delalibera, I; da Silva, C A; Tamai, M A; Mumford, J D

    2000-06-01

    The cassava green mite, Mononychellus tanajoa (Bondar), is an exotic pest in Africa and is the target of a classical biological control programme. Field data from the Neotropics, where it is indigenous, are presented for the first time, charting the variation in abundance of M. tanajoa over several seasons. This was highly variable, with a characteristic trough mid-year and a peak at the turn of the year. This pattern corresponded positively with rainfall levels, appearing to fit a phenology also characteristic of African studies, where rainfall at the start of the wet season promotes a leaf flush and so growth in M. tanajoa populations. Analyses implied some impact of leaf-inhabiting predatory mites (predominantly Neoseiulus idaeus Denmark & Muma) and a considerable impact of the fungal pathogen Neozygites floridana Fisher on M. tanajoa populations. This pathogen was not observed in the host population for several (generally dry) periods implying survival outside the host, perhaps as resting spores. This is a particularly desirable characteristic of a biological control agent. It is therefore proposed that N. floridana might be of particular use in drier cassava-growing areas where rainfall at the outset of the wet season is not sufficiently intense to cause heavy M. tanajoa mortality but may be sufficient to stimulate epizootics of the fungal pathogen, protecting the flush of new cassava growth.

  13. Plant feeding by a predatory mite inhabiting cassava.

    Science.gov (United States)

    Magalhães, S; Bakker, F M

    2002-01-01

    Plant feeding by arthropod predators may strongly affect the dynamics of bi-and tri-trophic interactions. We tested whether a predatory mite, Typhlodromalus aripo, feeds upon its host plant, cassava. This predator species is an effective biological control agent of Monoychellus tanajoa (the cassava green mite or CGM) a herbivorous mite specific to cassava. We developed a technique to detect plant feeding, based on the use of a systemic insecticide. We found that T. aripo feeds upon plant-borne material, while other predatory mite species, Neoseiulus idaeus and Phytoseiulus persimilis, do not. Subsequently, we measured survival of juveniles and adult females of T. aripo and N. idaeus, both cassava-inhabiting predator species, on cassava leaf discs. Survival of T. aripo was higher than that of N. idaeus. Thus, T. aripo was able to withstand longer periods of prey scarcity. Because CGM populations fluctuate yearly and are heterogeneously distributed within plants, plant feeding may facilitate the persistence of populations of T. aripo in cassava fields and its control of CGM outbreaks.

  14. Efficacy of five selected acaricides against Tetranychus urticae (Acari: Tetranychidae) and their side effects on relevant natural enemies occurring in citrus orchards.

    Science.gov (United States)

    Urbaneja, Alberto; Pascual-Ruiz, Sara; Pina, Tatiana; Abad-Moyano, Raquel; Vanaclocha, Pilar; Montón, Helga; Dembilio, Oscar; Castañera, Pedro; Jacas, Josep A

    2008-08-01

    Three groups of natural enemies are fundamental in citrus IPM in Spain: coccinellid and phytoseiid predators and hymenopteran parasitoids. Tetranychus urticae Koch is an important pest affecting citrus, for which biological control has not yet been achieved; therefore, acaricides are commonly used to control it. The goal of this study was to measure the efficacy of different acaricides on this mite and their side effects on three natural enemies relevant for citrus (Cryptolaemus montrouzieri Mulsant, Neoseiulus californicus McGregor and Aphidius colemani Viereck). Some products proved highly effective against T. urticae and harmless to A. colemani (mineral oil, tebufenpyrad, clofentezine and fenazaquin). However, almost all products tested were slightly harmful for both the predators considered. Fenazaquin was even moderately harmful for N. californicus. Further studies, like that presented here, are necessary to gain a better understanding of integrating biological and chemical controls. When considering both efficacy and side effects on beneficial arthropods, the best options would seem to be mineral oil, tebufenpyrad and clofentezine. However, it is urgent to complete testing of the side effects of the acaricides used in citrus. This question is crucial if the fact that two recently introduced Tetranychidae are being controlled in citrus by chemical means exclusively is considered.

  15. Seletividade de acaricidas e inseticidas a ácaros predadores (Acari: Phytoseiidae encontrados em seringueira no centro-oeste do Brasil Side-effect of acaricides and insecticides to predatory mites (Acari: Phytoseiidae found in rubber-trees in mid-west Brazil

    Directory of Open Access Journals (Sweden)

    Noeli Juarez Ferla

    2006-04-01

    Full Text Available Euseius concordis (Chant e Neoseiulus anonymus (Chant & Baker são ácaros predadores da família Phytoseiidae comumente encontrados em seringueira (Hevea brasiliensis Muell. Arg. em Mato Grosso, região centro-oeste do Brasil. Este trabalho foi realizado para verificar o efeito de acaricidas e inseticidas-acaricidas empregados em plantações de seringueira, e outros que teriam potencial para serem empregados contra insetos e ácaros considerados pragas dessa cultura, sobre E. concordis e N. anonymus. Utilizou-se o método residual de pulverização em superfície, recomendado como padrão pelo Grupo de Trabalho "Pesticidas e Artrópodes Benéficos", da Organização Internacional de Controle Biológico e Integrado de Plantas e Animais Nocivos/Seção Regional do Paleártico Oeste. Duas concentrações de cada um dos seguintes ingredientes ativos foram utilizadas: acefato, dicofol, endosulfan, formetanate, metomil, monocrotofós, óxido de fenbutatin e propargite. Uma das concentrações utilizadas foi uma média daquelas sugeridas pelos fabricantes para o controle de ácaros e insetos fitófagos presentes em outras culturas, uma vez que nenhum dos produtos testados tem registro para o uso em seringueira e a outra correspondeu à cerca de um terço da primeira. Endosulfan a 320ppm, dicofol a 100ppm e óxido de fenbutatin a 100 e 320ppm foram inócuos a E. concordis, enquanto que endosulfan a 320ppm e dicofol a 100ppm foram inócuos a N. anonymus. Acefato, formetanate e monocrotofós, nas concentrações testadas, foram nocivos às duas espécies.Euseius concordis (Chant and Neoseiulus anonymus (Chant & Baker are predatory mites of the family Phytoseiidae commonly found on rubber trees (Hevea brasiliensis Muell. Arg. in the State of Mato Grosso, in the mid-west Brazil. This work was conducted to verify the effect of acaricides and insecticides-acaricides occasionally used in rubber tree plantations, and other products that could be used against

  16. INTERACCIÓN ENTRE DOS ÁCAROS DEPREDADORES DE Tetranychus urticae KOCH (ACARIFORMES: TETRANYCHIDAE EN LABORATORIO Interaction Between Two Predator Mites of Tetranychus urticae Koch (Acariformes: Tetranychidae in Laboratory

    Directory of Open Access Journals (Sweden)

    ANGÉLICA ARGÜELLES R

    2013-04-01

    Full Text Available Tetranychus urticae (Acari: Tetranychidae es una de las principales plagas de cultivos ornamentales, entre las especies más utilizadas para su control se encuentran Neoseiulus californicus y Phytoseiulus persimilis (Parasitiformes: Phytoseiidae. En el presente trabajo se propone el manejo de la plaga mediante el empleo de liberaciones simultáneas de los dos fitoseidos. Se evaluaron varias situaciones, por un lado se estudiaron las interacciones cuando un depredador se encuentra en una densidad baja mientras que el otro depredador se presenta en alta densidad (esta situación se analizó tanto en presencia como en ausencia de la presa. Por otro lado, se evaluaron las interacciones cuando los P. persimilis y N. californicus dos están presentes en igual densidad y en presencia de T. urticae. Cuando uno de los depredadores está en mayor densidad y hay presencia de la presa, se observa que al incrementar la edad del depredador que tiene menor densidad, aumenta también la interferencia en el consumo de presas por parte de los depredadores que están en mayor densidad. Además cuando disminuye el consumo de T. urticae se incrementa el consumo intraguilda. Phytoseiulus persimilis en ausencia de T. urticae y en presencia de N. californicus adopta un comportamiento de depredación intraguilda sobre todos los estados de desarrollo de su conespecifico, mientras que N. californicus únicamente consume larvas de conespecíficos en ausencia del fitófago y en presencia de P. persimilis. Cuando se encontraban los dos depredadores en el mismo montaje y la misma densidad de población, no se observó un mayor consumo de T. urticae que cuando cada depredador es empleado por separado.Tetranychus urticae (Acari: Tetranychidae is an important pest of ornamental crops. A species of predatory mite used for its control is Neoseiulus californicus and Phytoseiulus persimilis (Acari: Phytoseiidae. This research proposes the use of joint releases of the two cited

  17. Plantas de ocorrência espontânea como substratos alternativos para fitoseídeos (Acari, Phytoseiidae em cultivos de seringueira Hevea brasiliensis Muell. Arg. (Euphorbiaceae Weeds as alternative substrates to phytoseiids (Acari, Phytoseiidae in rubber tree Hevea brasilienis, Muell. Arg. (Euphorbiaceae cultivation

    Directory of Open Access Journals (Sweden)

    Marcos Roberto Bellini

    2005-03-01

    Full Text Available O objetivo deste estudo foi determinar as espécies de plantas espontâneas em áreas de cultivo de seringueira que poderiam servir com reservatório de ácaros predadores. O trabalho foi conduzido em Olímpia, Estado de São Paulo, Brasil, em dois cultivos de seringueira. A cada três meses, cerca de 1.000 cm³ de folhas de cada uma das cinco espécies de plantas espontâneas dominantes em cada cultivo foi tomada para determinar os fitoseídeos. Como as plantas espontâneas dominantes variaram durante o estudo, um total de 20 espécies foi verificado. Somente Cecropia sp. foi dominante em todo estudo, em ambos os cultivos. Um total de 336 fitoseídeos pertencentes às seguintes espécies foi encontrado: Euseius citrifolius Denmark & Muma, 1970, E. concordis (Chant, 1959, Galendromus annectens (DeLeon, 1958, Iphiseiodes zuluagai Denmark & Muma, 1972, Neoseiulus anonymus (Chant & Baker, 1965 e N. tunus (DeLeon, 1967. E. citrifolius (189 espécimes e N. tunus (138 espécimes foram os mais abundantes. A maior abundância (231espécimes e diversidade (5 espécies foram observadas sobre Cecropia sp. Sobre esta planta foi encontrado o maior número de ácaros por amostra (29 espécimes, seguida por Piper duncum Linnaeus (22, Guarea sp. (18 e Ageratum conyzoides Linnaeus (12. E. citrifolius tem sido determinado como um dos ácaros predadores mais abundantes sobre seringueiras cultivadas na região onde este trabalho foi conduzido. Cecropia sp. parece ser uma das plantas espontâneas mais importantes consideradas como reservatório de E. citrifolius porque está continuamente presente nos cultivos. Estudos complementares poderiam indicar a viabilidade de se manejar esta planta nas áreas de cultivo de seringueira para permitir o controle biológico dos ácaros-praga desta cultura.The objective of this study was to determine weed species of rubber tree cultivation areas that could serve as reservoirs of predatory mites. The work was conducted in Ol

  18. Interdependent effects of male and female body size plasticity on mating behaviour of predatory mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-02-01

    The adaptive canalization hypothesis predicts that traits with low phenotypic plasticity are more fitness relevant, because they have been canalized via strong past selection, than traits with high phenotypic plasticity. Based on differing male body size plasticities of the predatory mites Phytoseiulus persimilis (low plasticity) and Neoseiulus californicus (high plasticity), we accordingly hypothesized that small male body size entails higher costs in female choice and male-male competition in P. persimilis than N. californicus. Males of both species are highly polygynous but females differ in the level of polyandry (low level in P. persimilis; medium level in N. californicus). We videotaped the mating interactions in triplets of either P. persimilis or N. californicus, consisting of a virgin female (small or standard-sized) and a small and a standard-sized male. Mating by both small and standard-sized P. persimilis females was biased towards standard-sized males, resulting from the interplay between female preference for standard-sized males and the inferiority of small males in male-male competition. In contrast, mating by N. californicus females was equally balanced between small and standard-sized males. Small N. californicus males were more aggressive ('Napoleon complex') in male-male competition, reducing the likelihood of encounter between the standard-sized male and the female, and thus counterbalancing female preference for standard-sized males. Our results support the hypothesis that male body size is more important to fitness in the low-level polyandrous P. persimilis than in the medium-level polyandrous N. californicus and provide a key example of the implications of sexually selected body size plasticity on mating behaviour.

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

    Science.gov (United States)

    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.

  20. Risk assessment of non-target effects caused by releasing two exotic phytoseiid mites in Japan: can an indigenous phytoseiid mite become IG prey?

    Science.gov (United States)

    Sato, Yukie; Mochizuki, Atsushi

    2011-08-01

    Two exotic phytoseiid mites, Neoseiulus cucumeris and Amblyseius swirskii, are commercially available in Japan for the control of thrips and other pest insects. As part of a risk assessment of the non-target effects of releasing these two species, we investigated intraguild predation (IGP) between these exotic phytoseiid mites and an indigenous phytoseiid mite Gynaeseius liturivorus, which is promising as an indigenous natural enemy for the control of thrips in Japan. To understand IGP relations between the exotic and indigenous phytoseiid mites after use of the exotic mites for biological control, we investigated IGP between them in the absence of their shared prey. When an IG prey was offered to an IG predator, both exotic and indigenous females consumed the IG prey at all immature stages (egg, larva, protonymph, deutonymph), especially at its larval stages. The propensity for IGP in a no-choice test was measured by the survival time of IG prey corrected using the survival time of thrips offered to the IG predator. There was no significant difference in the propensity for IGP between N. cucumeris and G. liturivorus, but the propensity was significantly higher in A. swirskii than G. liturivorus. The propensity for IGP in a choice test was measured by the prey choice of the IG predator when a conspecific and a heterospecific larva were offered simultaneously as IG prey. Both exotic females consumed the heterospecific larva only. The indigenous female preferentially consumed the heterospecific larva when the heterospecific larva was N. cucumeris, but consumed the conspecific larva when the heterospecific larva was A. swirskii. We concluded that further investigation would be necessary for the exotic mites' risk assessment, since the propensity for IGP of the two exotic females was similar to or higher than that of the indigenous female in both the no-choice and choice tests.

  1. Threat-sensitive anti-intraguild predation behaviour: maternal strategies to reduce offspring predation risk in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2011-01-01

    Predation is a major selective force for the evolution of behavioural characteristics of prey. Predation among consumers competing for food is termed intraguild predation (IGP). From the perspective of individual prey, IGP differs from classical predation in the likelihood of occurrence because IG prey is usually more rarely encountered and less profitable because it is more difficult to handle than classical prey. It is not known whether IGP is a sufficiently strong force to evolve interspecific threat sensitivity in antipredation behaviours, as is known from classical predation, and if so whether such behaviours are innate or learned. We examined interspecific threat sensitivity in antipredation in a guild of predatory mite species differing in adaptation to the shared spider mite prey (i.e. Phytoseiulus persimilis, Neoseiulus californicus and Amblyseius andersoni). We first ranked the players in this guild according to the IGP risk posed to each other: A. andersoni was the strongest IG predator; P. persimilis was the weakest. Then, we assessed the influence of relative IGP risk and experience on maternal strategies to reduce offspring IGP risk: A. andersoni was insensitive to IGP risk. Threat sensitivity in oviposition site selection was induced by experience in P. persimilis but occurred independently of experience in N. californicus. Irrespective of experience, P. persimilis laid fewer eggs in choice situations with the high- rather than low-risk IG predator. Our study suggests that, similar to classical predation, IGP may select for sophisticated innate and learned interspecific threat-sensitive antipredation responses. We argue that such responses may promote the coexistence of IG predators and prey.

  2. Ultimate Drivers and Proximate Correlates of Polyandry in Predatory Mites.

    Science.gov (United States)

    Schausberger, Peter; Patiño-Ruiz, J David; Osakabe, Masahiro; Murata, Yasumasa; Sugimoto, Naoya; Uesugi, Ryuji; Walzer, Andreas

    2016-01-01

    Polyandry is more widespread than anticipated from Bateman's principle but its ultimate (evolutionary) causes and proximate (mechanistic) correlates are more difficult to pinpoint than those of polygyny. Here, we combined mating experiments, quantification of reproductive traits and microsatellite genotyping to determine the fitness implications of polyandry in two predatory mite species, where males are highly polygynous (up to 45 fertilized females during life), whereas females range from monandry to various polyandry levels. The medium-level polyandrous (up to eight male mates possible) Neoseiulus californicus received clear direct and indirect benefits: multiply mated females produced more offspring with higher survival chances over longer times than singly mated females. In contrast, singly and multiply mated females of the low-level polyandrous (commonly two male mates at maximum) Phytoseiulus persimilis produced similar numbers of offspring having similar survival chances. In both species, multiple mating resulted in mixed offspring paternities, opening the chance for indirect fitness benefits such as enhanced genetic compatibility, complementarity and/or variability. However, the female re-mating likelihood and the paternity chance of non-first male mates were lower in P. persimilis than in N. californicus. Regarding proximate factors, in both species first mating duration and female re-mating likelihood were negatively correlated. Based on occasional fertilization failure of first male mates in P. persimilis, and mixed offspring paternities in both species, we argue that fertilization assurance and the chance to gain indirect fitness benefits are the ultimate drivers of polyandry in P. persimilis, whereas those of N. californicus are higher offspring numbers coupled with enhanced offspring viability and possibly other indirect fitness benefits. Overall, the adaptive significance and proximate events well reflected the polyandry levels. Our study provides a

  3. Alternative food improves the combined effect of an omnivore and a predator on biological pest control. A case study in avocado orchards.

    Science.gov (United States)

    González-Fernández, J J; de la Peña, F; Hormaza, J I; Boyero, J R; Vela, J M; Wong, E; Trigo, M M; Montserrat, M

    2009-10-01

    Ecological communities used in biological pest control are usually represented as three-trophic level food chains with top-down control. However, at least two factors complicate this simple way of characterizing agricultural communities. First, agro-ecosystems are composed of several interacting species forming complicated food webs. Second, the structure of agricultural communities may vary in time. Efficient pest management approaches need to integrate these two factors to generate better predictions for pest control. In this work, we identified the food web components of an avocado agro-ecosystem, and unravelled patterns of co-occurrence and interactions between these components through field and laboratory experiments. This allowed us to predict community changes that would improve the performance of the naturally occurring predators and to test these predictions in field population experiments. Field surveys revealed that the food-web structure and species composition of the avocado community changed in time. In spring, the community was characterized by a linear food chain of Euseius stipulatus, an omnivorous mite, feeding on pollen. In the summer, E. stipulatus and a predatory mite, Neoseiulus californicus, shared a herbivorous mite prey. Laboratory experiments confirmed these trophic interactions and revealed that N. californicus can feed inside the prey nests, whereas E. stipulatus cannot, which may further reduce competition among predators. Finally, we artificially increased the coexistence of the two communities via addition of the non-herbivore food source (pollen) for the omnivore. This led to an increase in predator numbers and reduced populations of the herbivore. Therefore, the presence of pollen is expected to improve pest control in this system.

  4. Food stress causes sex-specific maternal effects in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-08-01

    Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring.

  5. Phenotypic plasticity in anti-intraguild predator strategies: mite larvae adjust their behaviours according to vulnerability and predation risk.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2013-05-01

    Interspecific threat-sensitivity allows prey to maximize the net benefit of antipredator strategies by adjusting the type and intensity of their response to the level of predation risk. This is well documented for classical prey-predator interactions but less so for intraguild predation (IGP). We examined threat-sensitivity in antipredator behaviour of larvae in a predatory mite guild sharing spider mites as prey. The guild consisted of the highly vulnerable intraguild (IG) prey and weak IG predator Phytoseiulus persimilis, the moderately vulnerable IG prey and moderate IG predator Neoseiulus californicus and the little vulnerable IG prey and strong IG predator Amblyseius andersoni. We videotaped the behaviour of the IG prey larvae of the three species in presence of either a low- or a high-risk IG predator female or predator absence and analysed time, distance, path shape and interaction parameters of predators and prey. The least vulnerable IG prey A. andersoni was insensitive to differing IGP risks but the moderately vulnerable IG prey N. californicus and the highly vulnerable IG prey P. persimilis responded in a threat-sensitive manner. Predator presence triggered threat-sensitive behavioural changes in one out of ten measured traits in N. californicus larvae but in four traits in P. persimilis larvae. Low-risk IG predator presence induced a typical escape response in P. persimilis larvae, whereas they reduced their activity in the high-risk IG predator presence. We argue that interspecific threat-sensitivity may promote co-existence of IG predators and IG prey and should be common in predator guilds with long co-evolutionary history.

  6. INTERACCIÓN ENTRE DOS ÁCAROS DEPREDADORES DE Tetranychus urticae KOCH (ACARIFORMES: TETRANYCHIDAE EN LABORATORIO

    Directory of Open Access Journals (Sweden)

    ANGÉLICA ARGÜELLES R

    2013-01-01

    Full Text Available Tetranychus urticae (Acari: Tetranychidae es una de las principales plagas de cultivos ornamentales, entre las especies más utilizadas para su control se encuentran Neoseiulus californicus y Phytoseiulus persimilis (Parasitiformes: Phytoseiidae. En el presente trabajo se propone el manejo de la plaga mediante el empleo de liberaciones simultáneas de los dos fitoseidos. Se evaluaron varias situaciones, por un lado se estudiaron las interac- ciones cuando un depredador se encuentra en una densidad baja mientras que el otro depredador se presenta en alta densidad (esta situación se analizó tanto en presencia como en ausencia de la presa. Por otro lado, se evaluaron las interacciones cuando los P. persimilis y N. californicus dos están presentes en igual densidad y en presencia de T. urticae. Cuando uno de los depredadores está en mayor densidad y hay presencia de la presa, se observa que al incrementar la edad del depredador que tiene menor densidad, aumenta también la interferencia en el consumo de presas por parte de los depre- dadores que están en mayor densidad. Además cuando disminuye el consumo de T. urticae se incrementa el consumo intraguilda. Phytoseiulus persimilis en ausencia de T. urticae y en presencia de N. californicus adopta un comportamiento de depredación intraguilda sobre todos los estados de desarrollo de su conespecifico, mientras que N. californicus únicamente consume larvas de conespecíficos en ausencia del fitófago y en presencia de P. persimilis. Cuando se encontraban los dos depredadores en el mismo montaje y la misma densidad de población, no se observó un mayor consumo de T. urticae que cuando cada depredador es empleado por separado.

  7. Two-spotted spider mite and its natural enemies on strawberry grown as protected and unprotected crops in Norway and Brazil.

    Science.gov (United States)

    Castilho, Raphael C; Duarte, Vanessa S; de Moraes, Gilberto J; Westrum, Karin; Trandem, Nina; Rocha, Luiz Carlos D; Delalibera, Italo; Klingen, Ingeborg

    2015-08-01

    Cultivation of strawberry in plastic tunnels has increased considerably in Norway and in southeastern Brazil, mainly in an attempt to protect the crop from unsuitable climatic factors and some diseases as well as to allow growers to expand the traditional production season. It has been hypothesized that cultivation under tunnels could increase the incidence of one of its major pests in many countries where strawberry is cultivated, including Norway and Brazil, the two spotted spider mite, Tetranychus urticae. The objective of this study was to evaluate the effect of the use of tunnels on the incidence of T. urticae and on its natural enemies on strawberry in two ecologically contrasting regions, Norway (temperate) and southeastern Brazil (subtropical). In both countries, peak densities of T. urticae in tunnels and in the open fields were lower than economic thresholds reported in the literature. Factors determining that systematically seem to be the prevailing relatively low temperature in Norway and high relative humidity in both countries. The levels of occurrence in Norway and Brazil in 2010 were so low that regardless of any potential effect of the use of tunnel, no major differences were observed between the two cropping systems in relation to T. urticae densities. In 2009 in Norway and in 2011 in Brazil, increase in T. urticae population seemed to have been restrained mainly by rainfall in the open field and by predatory mites in the tunnels. Phytoseiids were the most numerous predatory mite group of natural occurrence on strawberry, and the prevalence was higher in Brazil, where the most abundant species on strawberry leaves were Neoseiulus anonymus and Phytoseiulus macropilis. In Norway, the most abundant naturally occurring phytoseiids on strawberry leaves were Typhlodromus (Anthoseius) rhenanus and Typhlodromus (Typhlodromus) pyri. Predatory mites were very rare in the litter samples collected in Norway. Infection rate of the pest by the fungus Neozygites

  8. Phytoseiidae (Acari: Mesostigmata) within citrus orchards in Florida: species distribution, relative and seasonal abundance within trees, associated vines and ground cover plants.

    Science.gov (United States)

    Childers, Carl C; Denmark, Harold A

    2011-08-01

    Seven citrus orchards on reduced- to no-pesticide spray programs were sampled for predacious mites in the family Phytoseiidae (Acari: Mesostigmata) in central and south central Florida. Inner and outer canopy leaves, open flowers, fruit, twigs, and trunk scrapings were sampled monthly between September 1994 and January 1996. Vines and ground cover plants were sampled monthly between September 1994 and January 1996 in five of these orchards. The two remaining orchards were on full herbicide programs and ground cover plants were absent. Thirty-three species of phytoseiid mites were identified from 35,405 specimens collected within citrus tree canopies within the seven citrus orchards, and 8,779 specimens from vines and ground cover plants within five of the seven orchards. The six most abundant phytoseiid species found within citrus tree canopies were: Euseius mesembrinus (Dean) (20,948), Typhlodromalus peregrinus (Muma) (8,628), Iphiseiodes quadripilis (Banks) (2,632), Typhlodromips dentilis (De Leon) (592), Typhlodromina subtropica Muma and Denmark (519), and Galendromus helveolus (Chant) (315). The six most abundant species found on vines or ground cover plants were: T. peregrinus (6,608), E. mesembrinus (788), T. dentilis (451), I. quadripilis (203), T. subtropica (90), and Proprioseiopsis asetus (Chant) (48). The remaining phytoseiids included: Amblyseius aerialis (Muma), A. herbicolus (Chant), A. largoensis (Chant), A. multidentatus (Chant), A. sp. near multidentatus, A. obtusus (Koch), Chelaseius vicinus (Muma), Euseius hibisci Chant, Galendromus gratus (Chant), Metaseiulus mcgregori (Chant), Neoseiulus mumai (Denmark), N. vagus (Denmark), Phytoscutus sexpilis (Muma), Phytoseiulus macropilis (Banks), Proprioseiopsis detritus (Muma), P. dorsatus (Muma), P. macrosetae (Banks), P. rotundus (Muma), P. solens (De Leon), Typhlodromips deleoni (Muma), T. dillus (De Leon), T. dimidiatus (De Leon), T. mastus Denmark and Muma, T. simplicissimus (De Leon), and T. sp

  9. Gene identification and sequence analysis of Wolbachia in several common mites in citrus orchards%几种常见桔园螨类Wolbachia基因检测与序列分析

    Institute of Scientific and Technical Information of China (English)

    邹志文; 陈芬; 余丽萍; 夏斌

    2011-01-01

    Polymerase chain reaction ( PCR) was adopted to examine the wsp, ftsZ, and 16S rDNA of Wolbachia in Amblyseius orientalis, A. eharai, Euseius nicholsi, Neo.seiulus barkeri, Panonychus citri, and Tetranychus harti from the citrus orchards in Nanchang, Jiujiang, and Ganzhou of Jiangxi Province. It was found that only T. harti from the citrus orchards in Nanchang was infected by Wolbachia, with the fragments length of Wolbachia wsp ( Accession No. GQ162482) , ftsZ ( GQ162483) , and 16S rDNA ( GQ162484) being 593, 758, and 896 bp, respectively, while the other five species were uninfected. The Wolbachia in T. harti was very similar to the group Epo in subgroup B, based on the phylogenetic analysis of wsp gene.%应用共生菌沃尔巴克氏体Wolbachia的wsp、ftsZ和16S rDNA基因特异引物,通过PCR扩增法对采自江西省南昌、九江和赣州等3地桔园内的东方钝绥螨、江原钝绥螨、尼氏真绥螨、巴氏新小绥螨、桔全爪螨和酢浆草如叶螨等6种常见螨类进行了检测.结果表明,在采自南昌桔园内的酢浆草如叶螨体内检测到Wolbachia感染,其wsp、ftsZ和16S rDNA基因长度为593、758和896 bp,Genbank登录号依次为GQ162482、GQ162483和GQ162484,而其他5种螨体内均未检测出Wolbachia的感染;同时通过对酢浆草如叶螨体内感染的Wolbachia的wsp基因序列进行系统发育分析,得出其与B大组的Epo组的Wolbachia株十分相近,可能是相近或相同的株.