Sample records for amblyseius womersleyi schicha
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Shinmen, Tsubasa; Yano, Shuichi; Osakabe, Mh
2010-10-01
As it walks, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) spins a trail of silk threads, that is followed by the predatory mite, Neoseiulus womersleyi Schicha (Acari: Phytoseiidae). Starved adult female N. womersleyi followed T. urticae trails laid down by five T. urticae females but did not follow a trail of one T. urticae female, suggesting that the amount of spun threads and their chemical components should correlate positively with the number of T. urticae individuals. To examine whether chemical components of T. urticae trails are responsible for the predatory mite's trail following, we collected separate T. urticae threads from the exuviae and eggs, and then washed the threads with methanol to separate chemical components from physical attributes of the threads. Female N. womersleyi did not follow T. urticae trails that had been washed with methanol but contained physical residues, but they did follow the direction to which the methanol extracts of the T. urticae trails was applied. These results suggest that the predatory mite follows chemical, not physical, attributes of T. urticae trails.
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Park, Jung-Joon; Kim, Minsik; Lee, Joon-Ho; Shin, Key-Il; Lee, Sung Eun; Kim, Jeong-Gyu; Cho, Kijong
2011-07-01
Laboratory bioassays were conducted to evaluate the sublethal effects of fenpyroximate and pyridaben on life-table parameters of two predatory mites species, Neoseiulus (= Amblyseius) womersleyi and Phytoseiulus persimilis. In these assays, young adult females were treated with three sublethal concentrations of each acaricide. The life-table parameters were calculated at each acaricide concentration, and compared using bootstrap procedures. For each acaricide, the LC(50) estimates for both species were similar, yet the two species exhibited completely different susceptibility when the population growth rate was used as the endpoint. Exposure to both acaricides reduced the net reproduction rate (R (o)) in a concentration-dependent manner and their EC(50)s were equivalent to less than LC(7). Two different scales of population-level endpoints were estimated to compare the total effect between the species and treatments: the first endpoint values were based on the net reproductive rate (fecundity λ) and the second endpoint values incorporated the mean egg hatchability into the net reproductive rate (vitality λ). The fecundity λ decreased in a concentration-dependent manner for both acaricide treatments, but the vitality λ decreased abruptly after treatment of N. womersleyi with pyridaben. The change in the patterns of λ revealed that the acaricide effects at the population level strongly depended on the life-history characteristics of the predatory mite species and the chemical mode of action. When the total effects of the two acaricides on N. womersleyi and P. persimilis were considered, fenpyroximate was found to be the most compatible acaricide for the augmentative release of N. womersleyi after treatment.
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Ahn, Y J; Kim, Y J; Yoo, J K
2001-02-01
The toxicities of the herbicide glufosinate-ammonium to three predatory insect and two predatory mite species of Tetranychus urticae Koch were determined in the laboratory by the direct contact application. At a concentration of 540 ppm (a field application rate for weed control in apple orchards), glufosinate-ammonium was almost nontoxic to eggs of Amblyseius womersleyi Schicha, Phytoseiulus persimilis Athias-Henriot, and T. urticae but highly toxic to nymphs and adults of these three mite species, indicating that a common mode of action between predatory and phytophagous mites might be involved. In tests with predatory insects using 540 ppm, glufosinate-ammonium revealed little or no harm to larvae and pupae of Chrysopa pallens Rambur but was slightly harmful to eggs (71.2% mortality), nymphs (65.0% mortality), and adults (57.7% mortality) of Orius strigicollis Poppius. The herbicide showed no direct effect on eggs and adults of Harmonia axyridis (Pallas) but was harmful, slightly harmful, and harmless to first instars (100% mortality), fourth instars (51.1% mortality), and pupae (24.5% mortality), respectively. The larvae and nymphs of predators died within 12 h after treatment, suggesting that the larvicidal and nymphicidal action may be attributable to a direct effect rather than an inhibitory action of chitin synthesis. On the basis of our data, glufosinate-ammonium caused smaller effects on test predators than on T. urticae with the exception of P. persimilis, although the mechanism or cause of selectivity remains unknown. Glufosinate-ammonium merits further study as a key component of integrated pest management.
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Blommers, Leo
1974-01-01
Seven new species of the genus Amblyseius are described: Amblyseius (Proprioseiopsis) parasundi, A. (A.) tamatavensis, A. (A.) passiflorae, A. (A.) reptans, A. (A.) ivoloinae, A. (A.) ovaloides, A. (A.) aequidens. All species were collected on fruit trees except A. passiflorae. A. parasundi is a
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Dicke, M.; Sabelis, M.W.; Groeneveld, A.
1986-01-01
volatile kairomone of the two-spotted spider mite,Tetranychus urticae, elicits a searching response of the phytoseiid predatorAmblyseius potentillae, only when the predator is reared on a carotenoid-free diet. However, after addition of crystalline betta-carotene or vitamin A acetate to the
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Delisle, J F; Brodeur, J; Shipp, L
2015-04-01
Although phytoseiids are best known as predators of phytophagous mites and other small arthropods, several species can also feed and reproduce on pollen. In laboratory assays, we assessed the profitability of two types of dietary supplements (three pollen species-cattail, maize and apple-and eggs of the Mediterranean flour moth, Ephestia kuehniella) for the two species of predatory mites most commonly used as biocontrol agents in horticulture in Canada, Neoseiulus cucumeris and Amblyseius swirskii. We measured the effects of each diet on phytoseiid fitness parameters (survival, development, sex ratio, fecundity) and, as a means of comparison, when fed larvae of the common targeted pest species, western flower thrips Frankliniella occidentalis. A soluble protein assay was also performed on the alternative food sources as protein content is often linked to high nutritive value according to the literature. All food sources tested were suitable for N. cucumeris and A. swirskii, both species being able to develop from egg to adult. The dietary supplements had a beneficial impact on biological parameters, mostly resulting in shorter development times and higher survival rates when compared to thrips larvae. Amblyseius swirskii exhibited a wider dietary range than N. cucumeris. Overall, flour moth eggs, cattail pollen and apple pollen are food sources of equal quality for A. swirskii, whereas apple and cattail pollen are better when it comes to N. cucumeris. In contrast, maize pollen is a less suitable food source for N. cucumeris and A. swirskii. Soluble protein content results did not match the prediction under which the most beneficial food source would contain the highest concentration in protein.
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Xu, Xuenong; Enkegaard, Annie
2010-01-01
The prey preference of polyphagous predators plays an important role in suppressing different species of pest insects. In this study the prey preference of the predatory mite, Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) was examined between nymphs of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and first instar larvae of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), as well as between active and chrysa...
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Bostanian, Noubar J; Akalach, Mohammed
2006-04-01
A laboratory study assessed the contact toxicity of indoxacarb, abamectin, endosulfan, insecticidal soap, S-kinoprene and dimethoate to Amblyseius fallacis (Garman), Phytoseiulus persimilis Athias-Henriot and nymphs of Orius insidiosus (Say). Amblyseius fallacis is a predacious phytoseiid mite and an integral part of integrated pest management (IPM) programmes in North American apple orchards. The other two beneficials are widely used in greenhouses to manage various arthropod pests infesting vegetable and ornamental crops. Indoxacarb is a slow-acting insecticide, so toxicity data were recorded 7 days post-treatment when the data had stabilised. It showed no toxicity to O. insidiosus nymphs or to A. fallacis or P. persimilis adults. The LC50 values for O. insidiosus nymphs and P. persimilis could not be estimated with their associated confidence limits, because the g values were greater than 0.5 and under such circumstances the lethal concentration would lie outside the limits. The LC50 for A. fallacis was 7.6x the label rate. The fecundity of P. persimilis was reduced by 26.7%. The eclosion of treated eggs from both species of beneficial mites was not affected adversely. Among the other pest control products, S-kinoprene and endosulfan affected adversely at least one species of the predators, whereas dimethoate, abamectin and insecticidal soap were very toxic to all three beneficials. Indoxacarb should be evaluated as a pest control product in IPM programmes. Copyright (c) 2006 Crown in the right of Canada.
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Directory of Open Access Journals (Sweden)
Marjan Seiedy
2018-01-01
Full Text Available Introduction The predator Amblyseius swirskii and entomopathogenic fungus Beauveria bassiana are important biocontrol agents of Trialeurodes vaporariorum. Determination of the host preference of predators in the fields when receiving signals related to either untreated and Beauveria bassiana-treated pest is important. Materials and Methods In this research, the prey preference of adult female (2 days old of A. swirskii was determined on untreated and Beauveria bassiana-treated of Trialeurodes vaporariorum (Homoptera: Aleyrodidae in various treatments base on Manly Index. These different treatments consisted of two time intervals; 24 and 48 h post-inoculation of greenhouse whiteflies with 1×105 conidia /ml of B. bassiana with 13 replicates. 24-h starved predators were added to the leaf discs singly then the number of consumed untreated and B. bassiana-treated T. vaporariorum in each Petri dish was assessed after 24 h. Results and Discussion The results revealed that mean number of consumed B. bassiana-treated T. vaporariorum in two time intervals; 24 and 48 h. after inoculation were 4/15±0/19 and 2.23±0/12, respectively. This investigation showed a significant preference of A. swirskii towards untreated T. vaporariorum in 24 (P< 0.0034 and 48 h. (P
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Fernández, Maria Del Mar; Colomer, Ignacio; Medina, Pilar; Fereres, Alberto; Del Estal, Pedro; Viñuela, Elisa
2017-08-01
Insecticide-treated nets (ITNs) have been investigated recently for their use in agriculture. Depending on the insecticide, the hole size and the way they are produced, these nets can target different pests and therefore they could be interesting options for use in integrated pest management (IPM). As the information on their compatibility with beneficial fauna is practically negligible, in this work we have tested the compatibility of an experimental bifenthrin long-lasting insecticide-treated net (LLITN) with Amblyseius swirskii and Eretmocerus mundus, important natural enemies of whiteflies and thrips, under laboratory, semi-field and commercial greenhouse conditions. In the laboratory, the treated net was very deleterious to adults of both natural enemies, after 72 h exposure. However, in choice tests with Y-tubes, both natural enemies were neither attracted nor repelled by the treated net and no short-term mortality was detected in individuals that had crossed it. No deleterious effects on the E. mundus beneficial capacity were detected in semi-field trials. In field trials, the LLITN proved to be compatible with A. swirskii while decreasing pest densities. Bifenthrin LLITN studied could be a valuable method for reducing pest population infestations in IPM programmes while being compatible with biocontrol agents. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
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The Inventory of Phytoseiid Mite on Apple Orchards in Durrës, Albania
AURELA SUPARAKU; ARIS HUQI; NATASHA HAKA (DURAJ)
2014-01-01
A survey to determine the presence and abundance of phytoseiid mite on apple orchards has been conducted in Durres (Shena-Vlash), Albania. Leaf samples were taken from five apple varieties: Pink Lady, Golden, Starking, Fuji, Gala and the phytoseiid were then extracted. As the result of the survey, two species belonging to the Phytoseiidae family were identified: Amblyseius andersoni (Chant) and Typhlodromus pyri (Scheuten). Amblyseius andersoni was found in all apple varieties analyzed in thi...
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Directory of Open Access Journals (Sweden)
Tommy Rioja S
2009-06-01
Full Text Available The avocado red mite Oligonychus yothersi (McGregor is the major leaf pest in Chile’s avocado orchards. Itaffects leaf physiology and makes it necessary to seek new natural enemies to interact with low population densities of O. yothersi. The potentiality of three predator mites: Cydnodromus picanus Ragusa, Amblyseius graminis Chant, and Galendromus occidentalis (Nesbitt was evaluated under laboratory conditions (27 ± 1.93ºC, 87 ± 3.61% H.R. and 16:8 (L:D photoperiod on avocado leaf disks Persea americana Mill. var. Hass (Ø = 5 cm by separately feeding eggs, immature, and adult females of O. yothersi, and registering postembryonic development, consumption, as well as life table parameters. The postembryonic development of C. picanus was significantly lower (5.46 days compared to both A. graminis (7.33 days and G. occidentalis (8.69 days which were fed with immature O. yothersi. The life table parameters of C. picanus were net reproductive rate R0 = 25.41, finite rate of increase λ = 1.29, and Mean Generation Time T = 12.46. The Net Intrinsic Rate of Increase (r m was significantly higher for C. picanus (r m = 0.25 in contrast with G. occidentalis (r m = 0.19, while A. graminis showed r m = -0.06 indicating that its population didn’t have descendants. Under laboratory conditions, r m registered by C. picanus is an indicator of its predatory potential to control O. Yothersi. It can be assumed that the pest population reduction pattern could be maintained under field conditions.En Chile la arañita roja del palto Oligonychus yothersi (McGregor es la plaga más importante a nivel foliar en huertos comerciales afectando la fisiología de la hoja, siendo necesario la búsqueda de nuevos enemigos naturales que interactúen a bajas densidades poblacionales de O. yothersi. Se evaluó en condiciones de laboratorio (27±1,93ºC, 87±3,61 % H.R. y un fotoperíodo de 16:8 (L:O sobre discos de hojas de palto Persea americana Mill. var. Hass (Ø = 5
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Walzer, Andreas; Schausberger, Peter
2011-03-01
We studied developmental plasticity under food stress in three female-biased size dimorphic predatory mite species, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni. All three species prey on two-spotted spider mites but differ in the degree of adaptation to this prey. Phytoseiulus persimilis is a specialized spider mite predator, N. californicus is a generalist with a preference for spider mites, and A. andersoni is a broad generalist. Immature predators were offered prey patches of varying density and their survival chances, dispersal tendencies, age and size at maturity measured. Amblyseius andersoni dispersed earlier from and had lower survival chances in low density prey patches than N. californicus and P. persimilis. Age at maturity was not affected by prey density in the generalist A. andersoni, whereas both the specialist P. persimilis and the generalist N. californicus accelerated development at low prey densities. Species-specific plasticity in age at maturity reflects opposite survival strategies when confronted with limited prey: to prematurely leave and search for other food (A. andersoni) or to stay and accelerate development (P. persimilis, N. californicus). In all species, size at maturity was more plastic in females than males, indicating that males incur higher fitness costs from deviations from optimal body size.
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Phytoseiid mites from tropical fruit trees in Bahia State, Brazil (Acari, Phytoseiidae).
de Souza, Izabel Vieira; Sá Argolo, Poliane; Júnior, Manoel Guedes Correa Gondim; de Moraes, Gilberto José; Bittencourt, Maria Aparecida Leão; Oliveira, Anibal Ramadan
2015-01-01
The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them.
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Nuclear medicine. 1 part. Manual
International Nuclear Information System (INIS)
Shlygina, O.E.; Borisenko, A.R.
2006-01-01
Current manual is urged to give wide-scale readers a submission on a key principles and methods of nuclear medicine, and it opportunities and restrictions in diagnostics and treatment of different diseases. Nuclear medicine is differing first of all by combination of diverse knowledge fields: special knowledge of a doctor, knowledge of physical processes bases, related with radiation, grounds of radiopharmaceutics, dosimetry. In the base of the book the 5th edition of 'Nuclear medicine' manual in 2 parts of German authors - Schicha, G.; Schober, O. is applied. In the book publishing the stuff of the Institute of Nuclear Physics of the National Nuclear Center of Republic of Kazakhstan has been worked. Modifications undergo practically all chapters: especially the second one, forth and sixth was enlarged. The 1 part of the book was published due to support of IAEA within the Technical cooperation project 'Implementation of Nuclear Medicine and Biophysics Center' (KAZ/6/007). The manual second part - devoted to applications of nuclear medicine methods for diagnostics and treatment - will be published in 2007
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Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A
2017-01-01
Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.
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A Fundamental Step in IPM on Grapevine: Evaluating the Side Effects of Pesticides on Predatory Mites
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Alberto Pozzebon
2015-10-01
Full Text Available Knowledge on side effects of pesticides on non-target beneficial arthropods is a key point in Integrated Pest Management (IPM. Here we present the results of four experiments conducted in vineyards where the effects of chlorpyrifos, thiamethoxam, indoxacarb, flufenoxuron, and tebufenozide were evaluated on the generalist predatory mites Typhlodromus pyri Scheuten and Amblyseius andersoni (Chant, key biocontrol agents of herbivorous mites on grapevines. Results show that indoxacarb and tebufenozide had a low impact on the predatory mites considered here, while a significant impact was observed for chlorpyrifos, flufenoxuron, and thiamethoxam. The information obtained here should be considered in the design of IPM strategies on grapevine.
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Bemisia tabaci is a polyphagous pest known to feed upon over 900 plant taxa, and is an effective vector of more than 100 plant damaging viruses. Among different biotypes of this cryptic species complex, MEAM1 and MED whitefly are the two most destructive members posing threats of several crops of ec...
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Constitutive and Operational Variation of Learning in Foraging Predatory Mites.
Seiter, Michael; Schausberger, Peter
2016-01-01
Learning is widely documented across animal taxa but studies stringently scrutinizing the causes of constitutive or operational variation of learning among populations and individuals are scarce. The ability to learn is genetically determined and subject to constitutive variation while the performance in learning depends on the immediate circumstances and is subject to operational variation. We assessed variation in learning ability and performance of plant-inhabiting predatory mites, Amblyseius swirskii, caused by population origin, rearing diet, and type of experience. Using an early learning foraging paradigm, we determined that homogeneous single prey environments did not select for reduced learning ability, as compared to natural prey-diverse environments, whereas a multi-generational pollen diet resulted in loss of learning, as compared to a diet of live prey. Associative learning produced stronger effects than non-associative learning but both types of experience produced persistent memory. Our study represents a key example of environmentally caused variation in learning ability and performance.
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Constitutive and Operational Variation of Learning in Foraging Predatory Mites.
Directory of Open Access Journals (Sweden)
Michael Seiter
Full Text Available Learning is widely documented across animal taxa but studies stringently scrutinizing the causes of constitutive or operational variation of learning among populations and individuals are scarce. The ability to learn is genetically determined and subject to constitutive variation while the performance in learning depends on the immediate circumstances and is subject to operational variation. We assessed variation in learning ability and performance of plant-inhabiting predatory mites, Amblyseius swirskii, caused by population origin, rearing diet, and type of experience. Using an early learning foraging paradigm, we determined that homogeneous single prey environments did not select for reduced learning ability, as compared to natural prey-diverse environments, whereas a multi-generational pollen diet resulted in loss of learning, as compared to a diet of live prey. Associative learning produced stronger effects than non-associative learning but both types of experience produced persistent memory. Our study represents a key example of environmentally caused variation in learning ability and performance.
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Directory of Open Access Journals (Sweden)
M.A. Watanabe
1994-04-01
Full Text Available O ácaro rajado, Tetranychus urticae Koch, é considerado uma das principais pragas de hortaliças e várias outras culturas no Brasil, em áreas onde um considerável volume de acaricidas é anualmente empregado no seu controle. O objetivo deste trabalho foi testar a viabilidade técnica do emprego dos fitoseídeos Amblyseius idaeus (Denmark & Muma e Phytoseudus macropilis (Banks, comum ente encontrados no Brasil, no controle de T. urticae em pepino e morangueiro em Jaguaríúna,SP. Utilizou-se o delineamento experimental em blocos casualizados, com 4 repetições e 4 tratamentos (T1-T4 para o pepino e 5 tratamentos para o morangueiro (T1-T5: T1, testemunha; T2, pulverizações semanais de Malation para a exclusão de predadores nativos; T3, liberações periódicas de A.idaeus; T4, liberações periódicas de P.macropilis; T5, pulverizações semanais de avermectina para a exclusão de ácaros fitófagos e predadores nativos. Apenas A.idaeus se estabeleceu na cultura de pepino, reduzindo significativamente a população de T. urticae. Ambas espécies de predadores se estabeleceram na cultura do morango e reduziram significativamente a população de T.urticae.The two-spotted spider mite, Tetranychus urticae Koch, is considered one of the main pests of horticultural and other crops in Brazil, in areas where a considerable volume of acaricides is annually used for its control. The objective of this work was to test the technical viability of using phytoseiids Amblyseius idaeus (Denmark & Muma and Phytoseudus macropilis (Banks, commonly found in Brazil, to control T .urticae in cucumber and strawberry crops in Jaguaríúna,SP. A randomized complete block design was used, with 4 replicates and 4 treatments for cucumber (T1-T4 and 5 treatments for strawberry crops (T1-T5: T1, control; T2, weekly sprays of malathion for exclusion of native predators; T3, periodical releases of A.idaeus; T4, periodical releases of P. macropilis; T5, weekly sprays of
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Groenewoud, G C M; de Graaf in 't Veld, C; vVan Oorschot-van Nes, A J; de Jong, N W; Vermeulen, A M; van Toorenenbergen, A W; Burdorf, A; de Groot, H; Gerth van Wijk, R
2002-07-01
Protection against thrips, a common pest in bell pepper horticulture is effectively possible without pesticides by using the commercially available predatory mite Amblyzeius cucumeris (Ac). The prevalence of sensitization to Ac among exposed greenhouse employees and its clinical relevance was studied. Four hundred and seventytwo employees were asked to fill in a questionnaire and were tested on location. Next to RAST, skin prick tests (SPTs) were performed with common inhalant allergens, the storage mite Tyrophagus putrescentiae (Tp) which serves as a temporary food source during the cultivation process and Ac. Furthermore, nasal challenge tests with Ac were carried out in 23 sensitized employees. SPTs positive to Ac were found in 109 employees (23%). Work-related symptoms were reported by 76.1%. Sensitization to Tp was found in 62 employees of whom 48 were also sensitized to Ac. Immunoglobulin (Ig)E-mediated allergy to inhalant allergens appeared to be an important risk factor for sensitization to Ac. Employees with rhinitis symptoms showed a significantly higher response to all Ac doses during the nasal challenge test compared with employees without rhinitis symptoms. The predatory mite Ac is a new occupational allergen in horticulture which can cause an IgE-mediated allergy in exposed employees. It is biologically active on the mucous membranes of the nose and therefore clinically relevant for the development of work-related symptoms.
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Tachi, Fuyuki; Osakabe, Masahiro
2012-12-01
Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites ( Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite ( Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species ( T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.
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Directory of Open Access Journals (Sweden)
Katarina KOS
2018-04-01
Full Text Available The two spotted spider mite, Tetranychus urticae C. L. Koch, 1836 is one of the most important pests of greenhouse crops worldwide. Due to its polyphagic range of hosts and rapid development it forms great populations and as such represents a suitable host/prey for lots of natural enemies usable in biological control. Most commonly used predators of Tetranychid mites are predatory mites (Phytoseiulus persimilis Athias-Henriot, 1957, Amblyseius swirskii Athias-Henriot, 1962 ,…, but among most voracious predators is the larva of a predatory gall midge, Feltiella acarisuga (Vallot, 1827 that was found also in greenhouses of the Biotechnical Faculty in Ljubljana on eggplant leaves in 2017. Besides the predatory gall midge also another predator, staphylinid Oligota oviformis Casey, 1893 beetles and larvae were found in great numbers. After positive identification of F. acarisuga found naturally in Slovenia, it can be added to the list of indigenous species of natural enemies and thus can be used in biological control programs in greenhouse crop protection against spider mites.
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ÁCAROS ASOCIADOS AL CULTIVO DEL AGUACATE (Persea americana Mill EN LA COSTA CENTRAL DE PERÚ
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Jorge Luis Muñoz Marticorena
2014-01-01
Full Text Available En la costa central de Perú (Lima e Ica, se cultiva el aguacate con fines de exportación, especialmente la variedad Hass. Con el objetivo de conocer la diversidad de ácaros depredadores en huertos comerciales de aguacate, se realizaron recolectas en 6 lugares de la costa central, duran - te el 2010 al 2012. Se registraron 12 especies de la familia Phytoseiidae, de los cuales algunos tendrían potencial como depredadores eficien - tes de Oligonychus sp . (Guanilo et ál. 2012; estos son: Amblyseius aerialis (Muma, Ambly - seius chungas (Demmark y Muma, Amblyseiella setosa (Muma, Euseius emanus (El–Banhawy, Euseius concordis (Chant, Euseius stipulatus (Athias–Henriot, Phytoseiulus persimilis (Athias Henriot, Phytoseiulus macropilis (Banks, Neo - seiulus californicus (McGregor, Typhlodromina subtropica (Chant, Typhlodromus ( Antoseius evectus (Schusters y Aristadromips n.sp. Se con - firmó que la vegetación espontánea cumple un rol importante en la conservación de las especies halladas en este cultivo y que además la intro - ducción de un ácaro depredador exótico, como Euseius stipulatus, contribuyó significativamente con el control de la plaga durante la temporada de invierno.
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Maternal intraguild predation risk affects offspring anti-predator behavior and learning in mites
Seiter, Michael; Schausberger, Peter
2015-01-01
Predation risk is a strong selective force shaping prey morphology, life history and behavior. Anti-predator behaviors may be innate, learned or both but little is known about the transgenerational behavioral effects of maternally experienced predation risk. We examined intraguild predation (IGP) risk-induced maternal effects on offspring anti-predator behavior, including learning, in the predatory mite Phytoseiulus persimilis. We exposed predatory mite mothers during egg production to presence or absence of the IG predator Amblyseius andersoni and assessed whether maternal stress affects the anti-predator behavior, including larval learning ability, of their offspring as protonymphs. Protonymphs emerging from stressed or unstressed mothers, and having experienced IGP risk as larvae or not, were subjected to choice situations with and without IG predator traces. Predator-experienced protonymphs from stressed mothers were the least active and acted the boldest in site choice towards predator cues. We argue that the attenuated response of the protonymphs to predator traces alone represents optimized risk management because no immediate risk existed. Such behavioral adjustment could reduce the inherent fitness costs of anti-predator behaviors. Overall, our study suggests that P. persimilis mothers experiencing IGP risk may prime their offspring to behave more optimally in IGP environments. PMID:26449645
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Behavioural responses of two-spotted spider mites induced by predator-borne and prey-borne cues.
Gyuris, Enikő; Szép, Erna; Kontschán, Jenő; Hettyey, Attila; Tóth, Zoltán
2017-11-01
Applying predatory mites as biological control agents is a well established method against spider mites which are major pests worldwide. Although antipredator responses can influence the outcome of predator-prey interactions, we have limited information about what cues spider mites use to adjust their behavioural antipredator responses. We experimentally exposed two-spotted spider mites (Tetranychus urticae) to different predator-borne cues (using a specialist predator, Phytoseiulus persimilis, or a generalist predator, Amblyseius swirskii), conspecific prey-borne cues, or both, and measured locomotion and egg-laying activity. The reactions to predator species compared to each other manifested in reversed tendencies: spider mites increased their locomotion activity in the presence of P. persimilis, whereas they decreased it when exposed to A. swirskii. The strongest response was triggered by the presence of a killed conspecific: focal spider mites decreased their locomotion activity compared to the control group. Oviposition activity was not affected by either treatment. Our results point out that spider mites may change their behaviour in response to predators, and also to the presence of killed conspecifics, but these effects were not enhanced when both types of cues were present. The effect of social contacts among prey conspecifics on predator-induced behavioural defences is discussed. Copyright © 2017 Elsevier B.V. All rights reserved.
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Directory of Open Access Journals (Sweden)
Castro V. Ulises
1999-06-01
Full Text Available En la empresa "Flores del Cauca" en el municipio de Piendamó a 1S00 m.s.n.m. con temperatura promedia de 18° C y HR de SO ± 5%, se hizo una búsqueda de enemigos naturales nativos de F. occidentalis (Thysanóptera: Thripidae sobre eras experimentales de Dendranthema grandiflorum libres de control químico. La búsqueda se extendió a los hospedantes alternos del tisanóptero en áreas aledañas al cultivo. Semanalmente se cosechaban plantas de crisantemo, se llevaban al laboratorio para la recolección de thrips y sus enemigos naturales nativos. En el laboratorio se realizaron bioensayos para probar la acción depredadora de algunos de los enemigos de F. occídentalis que fueron encontrados en crisantemo. Se encontraron los siguientes enemigos naturales nativos: El hemíptero Orius sp. (Anthocoridae. los ácaros Amblyseius herbjcolus. Euseius naindaimei y Thyplodromalus peregrinus (Phytoseiidae, larvas de Chrysopidae; los thrips leptothirs sp. y Haplotrips gowdeyi (Phlaeothripidae, un ácaro de la familia Ascidae; difereflles especies de arañas; larvas de la familia Coccinellidae y adultos de F. occidentalis infectados por hongos no identificados.
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Directory of Open Access Journals (Sweden)
Markus Andreas Strodl
Full Text Available Social familiarity, which is based on the ability to recognise familiar conspecific individuals following prior association, may affect all major life activities of group-living animals such as foraging, reproduction and anti-predator behaviours. A scarcely experimentally tested explanation why social familiarity is beneficial for group-living animals is provided by limited attention theory. Limited attention theory postulates that focusing on a given task, such as inspection and assessment of unfamiliar group members, has cognitive and associated physiological and behavioural costs with respect to the attention paid to other tasks, such as anti-predator vigilance and response. Accordingly, we hypothesised that social familiarity enhances the anti-predator success of group-living predatory mites, Phytoseiulus persimilis, confronted with an intraguild predator, the predatory mite Amblyseius andersoni.We videotaped and analysed the response of two P. persimilis larvae, held in familiar or unfamiliar pairs, to attacks by a gravid A. andersoni female, using the behavioural analyses software EthoVision Pro®. Familiar larvae were more frequently close together, reacted more quickly to predator attacks, survived more predator encounters and survived longer than unfamiliar larvae.In line with the predictions of limited attention theory, we suggest that social familiarity improves anti-predator behaviours because it allows prey to shift attention to other tasks rather than group member assessment.
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Strodl, Markus Andreas; Schausberger, Peter
2012-01-01
Background Social familiarity, which is based on the ability to recognise familiar conspecific individuals following prior association, may affect all major life activities of group-living animals such as foraging, reproduction and anti-predator behaviours. A scarcely experimentally tested explanation why social familiarity is beneficial for group-living animals is provided by limited attention theory. Limited attention theory postulates that focusing on a given task, such as inspection and assessment of unfamiliar group members, has cognitive and associated physiological and behavioural costs with respect to the attention paid to other tasks, such as anti-predator vigilance and response. Accordingly, we hypothesised that social familiarity enhances the anti-predator success of group-living predatory mites, Phytoseiulus persimilis, confronted with an intraguild predator, the predatory mite Amblyseius andersoni. Methodology/Principal Findings We videotaped and analysed the response of two P. persimilis larvae, held in familiar or unfamiliar pairs, to attacks by a gravid A. andersoni female, using the behavioural analyses software EthoVision Pro®. Familiar larvae were more frequently close together, reacted more quickly to predator attacks, survived more predator encounters and survived longer than unfamiliar larvae. Significance In line with the predictions of limited attention theory, we suggest that social familiarity improves anti-predator behaviours because it allows prey to shift attention to other tasks rather than group member assessment. PMID:22927997
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Howell, Anna D; Daugovish, Oleg
2013-02-01
The spider mite, Eotetranychus lewisi (McGregor) (Acari: Tetranychidae), is a new emerging pest in California commercial strawberries. The predatory mite Phytoseiulus persimilis (Athias-Henriot) (Acari: Phytoseiidae), typically used for biocontrol of Tetranychus urticae (Koch) (Acari: Tetranychidae), provided growers little to no control of E. lewisi. Four commonly used phytoseiid predatory mites: P. persimilis, Neoseiulus californicus (McGregor), N. fallacis (Garman), and Amblyseius andersoni (Chant), were used in lab studies to investigate which is best at managing E. lewisi populations. We als o investigated t he interactions between T. urticae and E. lewisi and in relation to phytoseiid efficiency given the potential for indirect effects of biocontrol. When E. lewisi and T. urticae are present on the same leaf, T. urticae populations increase and begin displacing E. lewisi. P. persimilis did not feed on E. lewisi, but the other three predatory mites consumed the spider mites and lowered their populations. When both E. lewisi and T. urticae are present on the same leaf, N. fallacis and A. andersoni fed on both types of mites equally and were capable of decreasing both populations. N. californicus fed on E. lewisi first and decreased its population, but allowed T. urticae populations to increase. P. persimilis may be insufficient at controlling E. lewisi and its use may instead enhance E. lewisi populations.
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Lime sulfur toxicity to broad mite, to its host plants and to natural enemies.
Venzon, Madelaine; Oliveira, Rafael M; Perez, André L; Rodríguez-Cruz, Fredy A; Martins Filho, Sebastião
2013-06-01
An acaricidal effect of lime sulfur has not been demonstrated for Polyphagotarsonemus latus. However, lime sulfur can cause toxicity to natural enemies and to host plants. In this study, the toxicity of different concentrations of lime sulfur to P. latus, to the predatory mite Amblyseius herbicolus and to the predatory insect Chrysoperla externa was evaluated. Additionally, the phytotoxicity of lime sulfur to two P. latus hosts, chili pepper and physic nut plants, was determined. Lime sulfur at a concentration of 9.5 mL L(-1) restrained P. latus population growth. However, this concentration was deleterious to natural enemies. The predatory mite A. herbicolus showed a negative value of instantaneous growth rate, and only 50% of the tested larvae of C. externa reached adulthood when exposed to 10 mL L(-1) . Physic nut had severe injury symptoms when sprayed with all tested lime sulfur concentrations. For chili pepper plants, no phytoxicity was observed at any tested concentration. Lime sulfur might be used for P. latus control on chili pepper but not on physic nut owing to phytotoxicity. Care should be taken when using lime sulfur in view of negative effects on natural enemies. Selective lime sulfur concentration integrated with other management tactics may provide an effective and sustainable P. latus control on chili pepper. © 2012 Society of Chemical Industry.
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International Nuclear Information System (INIS)
Franco, Renato A.; Reis, Paulo R.; Oliveira, Daniel C.
2010-01-01
Oligonychus ilicis (McGregor) is among those mite species that can cause damage to coffee plants (Coffea spp.). Species of Phytoseiidae acari are considered the most important and studied predatory mites. The objective of this study was to evaluate the effects of the webbing produced by O. ilicis on its predation by females of the phytoseiids Iphiseiodes zuluagai Denmark and Muma, Euseius citrifolius Denmark and Muma and Amblyseius herbicolus (Chant). Four bioassays were conducted, with three treatments and ten replicates. Each replicate consisted of 25 O. ilicis per experimental unit (a leaf disc of Coffea arabica) according to the tested developmental stage, in independent experiments. To spin the web, 15 adult females were put on each experimental unit for 24h; females were then removed, leaving only the web, and predators and prey to be tested were introduced. Predation was assessed after 24h. In the presence of webbing, the consumption of eggs, larvae and nymphs by I. zuluagai and eggs and larvae by E. citrifolius was lower. For A. herbicolus, egg predation was lower, but larval predation did not vary significantly and predation of nymphs and adults was higher in the presence of webbing. Predators as a whole were more efficient consuming larvae regardless of the presence of webbing. Considering the stages of O. ilicis altogether, webbing reduced the predation potential of I. zuluagai and E. citrifolius, but not of A. herbicolus. (author)
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Calvet, Érica C; Lima, Debora B; Melo, José W S; Gondim, Manoel G C
2018-03-01
Organisms are adapted to recognize environmental cues that can provide information about predation risk or competition. Non-vagrant eriophyoid mites mainly avoid predation by using habitats that are difficult for predators to access (galls or confined spaces in plants) such as the meristematic region of the coconut fruit, which is inhabited by the phytophagous mites Aceria guerreronis and Steneotarsonemus concavuscutum. The objective of this study was to investigate the response of A. guerreronis to cues from the predators Neoseiulus baraki and Amblyseius largoensis in coconut fruits, cues from conspecifics (A. guerreronis injured) and cues from the phytophage S. concavuscutum. The test was carried out through the release of about 300 A. guerreronis on coconut fruits previously treated with cues from predators, conspecific or heterospecific phytophagous. We also observed the walking behaviour of A. guerreronis exposed to the same chemical cues using a video tracking system. The infestation of fruits by A. guerreronis was greater in the presence of predator cues and reduced in the presence of S. concavuscutum cues, but cues from injured conspecifics did not interfere in the infestation process. In addition, the cues also altered the walking parameters of A. guerreronis: it walked more in response to cues from predators and the heterospecific phytophage. Aceria guerreronis spent more time in activity in the treatments with clues than in the control treatment. These results suggest that A. guerreronis recognizes cues from predators and competitors and modifies its behaviour to increase its fitness.
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Walzer, Andreas; Schausberger, Peter
2013-01-01
Intraguild (IG) prey is commonly confronted with multiple IG predator species. However, the IG predation (IGP) risk for prey is not only dependent on the predator species, but also on inherent (intraspecific) characteristics of a given IG predator such as its life-stage, sex or gravidity and the associated prey needs. Thus, IG prey should have evolved the ability to integrate multiple IG predator cues, which should allow both inter- and intraspecific threat-sensitive anti-predator responses. Using a guild of plant-inhabiting predatory mites sharing spider mites as prey, we evaluated the effects of single and combined cues (eggs and/or chemical traces left by a predator female on the substrate) of the low risk IG predator Neoseiulus californicus and the high risk IG predator Amblyseius andersoni on time, distance and path shape parameters of the larval IG prey Phytoseiulus persimilis. IG prey discriminated between traces of the low and high risk IG predator, with and without additional presence of their eggs, indicating interspecific threat-sensitivity. The behavioural changes were manifest in distance moved, activity and path shape of IG prey. The cue combination of traces and eggs of the IG predators conveyed other information than each cue alone, allowing intraspecific threat-sensitive responses by IG prey apparent in changed velocities and distances moved. We argue that graded responses to single and combined IG predator cues are adaptive due to minimization of acceptance errors in IG prey decision making. PMID:23750040
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Vásquez, Carlos; de Moraes, Gilberto J
2013-05-01
The red palm mite (RPM), Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive pest in the New World, where it is currently considered a serious threat to coconut and banana crops. It was first reported from northern Venezuela in 2007. To determine its current distribution in this country, surveys were carried out from October 2008 to April 2010 on coconut (Cocos nucifera L.), banana (Musa spp.), ornamental plants and weeds in northern Venezuela. Higher population levels of RPM were registered on commercial coconut farms in Falcón and Sucre states but also on other plant species naturally growing along the coastal line in Anzoategui, Aragua, Carabobo, Monagas and Nueva Esparta states. Out of 34 botanical species evaluated, all RPM stages were observed only on eight arecaceous, one musaceous and one streliziaceous species, indicating that the pest developed and reproduced only on these plants. Mite specimens found on weeds were considered spurious events, as immature stages of the pest were never found on these. Amblyseius largoensis (Muma) (Acari: Phytoseiidae) was the most frequent predatory mite associated with RPM in all sampling sites. The results indicate that RPM has spread to extensive areas of northern Venezuela since its initial detection in Güiria, Sucre state. Considering the report of this pest mite in northern Brazil in the late 2009, additional samplings in southern Venezuela should be carried out, to evaluate the possible presence of RPM also in that region.
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Energy Technology Data Exchange (ETDEWEB)
Franco, Renato A. [Bioagri Laboratorios Ltda., Piracicaba, SP (Brazil)], e-mail: r.franco@bioagri.com.br; Reis, Paulo R. [Empresa de Pesquisa Agropecuaria de Minas Gerais (EPAMIG), Belo Horizonte, MG (Brazil). Ecocentro], e-mail: paulo.rebelles@epamig.ufla.br; Zacarias, Mauricio S. [EMBRAPA Cafe, Lavras, MG (Brazil)], e-mail: zacarias@epamig.ufla.br; Oliveira, Daniel C. [Universidade Federal de Lavras (UFLA), MG (Brazil)
2010-01-15
Oligonychus ilicis (McGregor) is among those mite species that can cause damage to coffee plants (Coffea spp.). Species of Phytoseiidae acari are considered the most important and studied predatory mites. The objective of this study was to evaluate the effects of the webbing produced by O. ilicis on its predation by females of the phytoseiids Iphiseiodes zuluagai Denmark and Muma, Euseius citrifolius Denmark and Muma and Amblyseius herbicolus (Chant). Four bioassays were conducted, with three treatments and ten replicates. Each replicate consisted of 25 O. ilicis per experimental unit (a leaf disc of Coffea arabica) according to the tested developmental stage, in independent experiments. To spin the web, 15 adult females were put on each experimental unit for 24h; females were then removed, leaving only the web, and predators and prey to be tested were introduced. Predation was assessed after 24h. In the presence of webbing, the consumption of eggs, larvae and nymphs by I. zuluagai and eggs and larvae by E. citrifolius was lower. For A. herbicolus, egg predation was lower, but larval predation did not vary significantly and predation of nymphs and adults was higher in the presence of webbing. Predators as a whole were more efficient consuming larvae regardless of the presence of webbing. Considering the stages of O. ilicis altogether, webbing reduced the predation potential of I. zuluagai and E. citrifolius, but not of A. herbicolus. (author)
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Wu, Shengyong; Gao, Yulin; Zhang, Yaping; Wang, Endong; Xu, Xuenong; Lei, Zhongren
2014-01-01
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 1×107 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 1×107 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. PMID:24454744
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Directory of Open Access Journals (Sweden)
Ester Azevedo Silva
2010-10-01
Full Text Available Existem poucas informações sobre a fauna de ácaros predadores (Phytoseiidae em ambientes naturais brasileiros adjacentes a agroecossistemas cafeeiros (Coffea spp. ou sobre a influência que essa vegetação exerce como reservatório de ácaros predadores. Neste estudo, objetivou-se avaliar a diversidade destes organismos em cafeeiros e fragmentos florestais adjacentes. Coletaram-se amostras das espécies Calyptranthes clusiifolia (Miq. O. Berg (Myrtaceae, Esenbeckia febrifuga (A. St.-Hil. A. Juss. ex Mart. (Rutaceae, Metrodorea stipularis Mart. (Rutaceae e Allophylus semidentatus (Miq. Radlk. (Sapindaceae, em oito fragmentos florestais, de 5 a 51 ha, e cafezais adjacentes, nos meses de junho (final período chuvoso e outubro (final período seco nos anos 2004 e 2005, na região Sul do Estado de Minas Gerais. Ácaros foram extraídos das folhas, utilizando o método de lavagem e, em seguida, montados em lâminas de microscopia em meio de Hoyer, para identificação específica. No total foram identificados 2.348 fitoseídeos, sendo 2.090 nos fragmentos florestais e 258 espécimes nos cafezais adjacentes, pertencentes a 38 espécies. Servindo-se de análise faunística, a espécie Iphiseiodes zuluagai Denmark & Muma, 1972 apresentou os melhores índices no agroecossistema cafeeiro, sendo muito frequente e constante nas épocas estudadas. Nos fragmentos florestais Amblyseius herbicolus Chant, 1959, Iphiseiodes affs. neonobilis Denmark & Muma, 1978, Leonseius regularis DeLeon, 1965 e Euseius alatus DeLeon, 1966 foram dominantes, muito abundantes, muito frequentes e constantes nas épocas estudadas. Podemos concluir que a vegetação nativa abriga ácaros predadores, inimigos naturais de ácaros-praga, que ocorrem na cultura cafeeira, possibilitando o desenvolvimento de programas de manejo ecológico com áreas de vegetação natural e agroecossistemas cafeeiros adjacentes.There is little information about the fauna of predatory mites
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Integration of multiple intraguild predator cues for oviposition decisions by a predatory mite
Walzer, Andreas; Schausberger, Peter
2012-01-01
In mutual intraguild predation (IGP), the role of individual guild members is strongly context dependent and, during ontogeny, can shift from an intraguild (IG) prey to a food competitor or to an IG predator. Consequently, recognition of an offspring's predator is more complex for IG than classic prey females. Thus, IG prey females should be able to modulate their oviposition decisions by integrating multiple IG predator cues and by experience. Using a guild of plant-inhabiting predatory mites sharing the spider mite Tetranychus urticae as prey and passing through ontogenetic role shifts in mutual IGP, we assessed the effects of single and combined direct cues of the IG predator Amblyseius andersoni (eggs and traces left by a female on the substrate) on prey patch selection and oviposition behaviour of naïve and IG predator-experienced IG prey females of Phytoseiulus persimilis. The IG prey females preferentially resided in patches without predator cues when the alternative patch contained traces of predator females or the cue combination. Preferential egg placement in patches without predator cues was only apparent in the choice situation with the cue combination. Experience increased the responsiveness of females exposed to the IG predator cue combination, indicated by immediate selection of the prey patch without predator cues and almost perfect oviposition avoidance in patches with the cue combination. We argue that the evolution of the ability of IG prey females to evaluate offspring's IGP risk accurately is driven by the irreversibility of oviposition and the functionally complex relationships between predator guild members. PMID:23264692
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Fernández Ferrari, M. Celeste; Schausberger, Peter
2013-06-01
Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.
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Directory of Open Access Journals (Sweden)
Gemma Albendín
2015-03-01
Full Text Available Biological control techniques are commonly used in many horticultural crops in Spain, however the application of these techniques to Spanish strawberries are relatively recent. In this study the effectiveness of augmentative biological control techniques to control the two main strawberry (Fragaria xananassa Duchesne pest: the two-spotted spider mite (TSSM, Tetranychus urticae Koch (Acari: Tetranychidae, and the western flower thrips (WFT, Frankliniella occidentalis (Pergande (Thysanoptera: Thripidae, through releases of the predatory mites Phytoseiulus persimilis Athias-Henriot, Neoseiulus californicus (McGregor, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae, and Orius laevigatus (Fieber (Heteroptera: Anthocoridae were tested. Two-year results on the performance of treatments using combinations of these biocontrol agents are presented. In both years, all treatments resulted in the reduction of TSSM numbers; but no treatment was better than the release of P. persimilis alone (P < 0.05. TSSM suppression varied among crop phases being greater early in the season. None of the treatments reduced significantly WFT numbers (P < 0.05, and the established economic injury level (EIL was surpassed from March to late April in both years. However, EIL was surpassed less times when treatment included O. laevigatus (2009: 20.7%; 2010: 22.7% of samples. No effect of A. swirskii was observed when this mite was released. Results corroborate that biological control techniques for TSSM and WFT are feasible for high-plastic tunnel strawberries. Under the conditions in our study no additive effects were observed, and there was not advantage in the release of multiple natural enemies.
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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.
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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.
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Directory of Open Access Journals (Sweden)
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.
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Food stress causes sex-specific maternal effects in mites.
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. © 2015. Published by The Company of Biologists Ltd.
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Schausberger, Peter; Davaasambuu, Undarmaa; Saussure, Stéphanie; Christiansen, Inga C
2018-04-01
Behavioural plasticity can be categorized into activational (also termed contextual) and developmental plasticity. Activational plasticity allows immediate contextual behavioural changes, whereas developmental plasticity is characterized by time-lagged changes based on memory of previous experiences (learning). Behavioural plasticity tends to decline with age but whether this holds true for both plasticity categories and the effects of first-in-life experiences is poorly understood. We tackled this issue by assessing the foraging plasticity of plant-inhabiting predatory mites, Amblyseius swirskii , on thrips and spider mites following age-dependent prey experience, i.e. after hatching or after reaching maturity. Juvenile and young adult predator females were alternately presented thrips and spider mites, for establishing 1st and 2nd prey-in-life experiences, and tested, as gravid females, for their foraging plasticity when offered both prey species. Prey experience by juvenile predators resulted in clear learning effects, which were evident in likelier and earlier attacks on familiar prey, and higher proportional inclusion of familiar prey in total diet. First prey-in-life experience by juvenile but not adult predators resulted in primacy effects regarding attack latency. Prey experience by adult predators resulted mainly in prey-unspecific physiological changes, with easy-to-grasp spider mites providing higher net energy gains than difficult-to-grasp thrips. Prey experience by juvenile, but not adult, predators was adaptive, which was evident in a negative correlation between attack latencies and egg production. Overall, our study provides key evidence that similar experiences by juvenile and adult predators, including first-in-life experiences, may be associated with different types of behavioural plasticity, i.e. developmental and activational plasticity.
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Davaasambuu, Undarmaa; Saussure, Stéphanie; Christiansen, Inga C.
2018-01-01
Behavioural plasticity can be categorized into activational (also termed contextual) and developmental plasticity. Activational plasticity allows immediate contextual behavioural changes, whereas developmental plasticity is characterized by time-lagged changes based on memory of previous experiences (learning). Behavioural plasticity tends to decline with age but whether this holds true for both plasticity categories and the effects of first-in-life experiences is poorly understood. We tackled this issue by assessing the foraging plasticity of plant-inhabiting predatory mites, Amblyseius swirskii, on thrips and spider mites following age-dependent prey experience, i.e. after hatching or after reaching maturity. Juvenile and young adult predator females were alternately presented thrips and spider mites, for establishing 1st and 2nd prey-in-life experiences, and tested, as gravid females, for their foraging plasticity when offered both prey species. Prey experience by juvenile predators resulted in clear learning effects, which were evident in likelier and earlier attacks on familiar prey, and higher proportional inclusion of familiar prey in total diet. First prey-in-life experience by juvenile but not adult predators resulted in primacy effects regarding attack latency. Prey experience by adult predators resulted mainly in prey-unspecific physiological changes, with easy-to-grasp spider mites providing higher net energy gains than difficult-to-grasp thrips. Prey experience by juvenile, but not adult, predators was adaptive, which was evident in a negative correlation between attack latencies and egg production. Overall, our study provides key evidence that similar experiences by juvenile and adult predators, including first-in-life experiences, may be associated with different types of behavioural plasticity, i.e. developmental and activational plasticity. PMID:29765663
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Directory of Open Access Journals (Sweden)
Karol Imbachi L
2012-12-01
Full Text Available El daño ocasionado por los ácaros Polyphagotarsonemus latus (Banks y Phyllocoptruta oleivora (Ashmead en el cultivo de naranja Valencia (Citrus sinensis L. es reconocido tanto por el impacto económico como por el daño externo de los frutos. En este trabajo se evaluó el efecto de agentes biológicos para el control de estas plagas en un cultivo comercial de naranja Valencia en el municipio de Caicedonia, Valle del Cauca, Colombia. Se usó un diseño de bloques completos al azar para evaluar los tratamientos siguientes: (1 liberación de especies de Phytoseiidae nativos (Neoseiulus anonymus, Neoseiulus californicus, Iphiseiodes zuluagai y Amblyseius herbicolus en poblaciones de 500 individuos/árbol; (2 liberación de larvas de Chrysoperla carnea (100 larvas/árbol; (3 aplicación localizada de cipermetrina 2 cm³/lt como tratamiento de exclusión de agentes benéficos; y (4 testigo consistente en el tratamiento utilizado por los agricultores (aplicación localizada de abamectina, 1.5 cm³/lt. Las liberaciones de las especies benéficas y las aplicaciones de los tratamientos se realizaron sobre racimos florales y frutos marcados en el tercio medio de cada árbol. Las evaluaciones de daños se realizaron cada semana hasta la cosecha. Los tratamientos de liberación de Phytoseiidae, liberación de larvas de C. carnea y aplicación de abamectina presentaron el menor daño de P. latus; el tratamiento de exclusión de benéficos demostró la importancia de los agentes controladores naturales sobre la plaga. En el manejo de P. oleivora, los tratamientos de liberación de larvas de C. carnea y aplicación de abamectina presentaron los mejores resultados con el menor daño en frutos. La población de P. oleivora ocasionó daños significativos en el tratamiento de liberación de ácaros Phytoseiidae y exclusión de benéficos.
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Crops producing insecticidal crystal (Cry) proteins from the bacterium, Bacillus thuringiensis (Bt), are an important tool for managing lepidopteran pests on cotton and maize. However, the effects of these Bt crops on non-target organisms, especially natural enemies that provide biological control s...
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A revision of the family Ameroseiidae (Acari, Mesostigmata), with some data on Slovak fauna
Mašán, Peter
2017-01-01
, 1918 = Kleemannia plumosa (Oudemans, 1902); Ameroseius eumorphus Bregetova, 1977 and Kleemannia potchefstroomensis Kruger & Loots, 1980 = Kleemannia pseudoplumosa (Rack, 1972); Ameroseius gilarovi Petrova, 1986 = Kleemannia plumigera Oudemans, 1930; Ameroseius imparsetosus Westerboer, 1963 = Ameroseius georgei (Turk, 1943); Ameroseius lanatus Solomon, 1969 and Ameroseius fimetorum Karg, 1971 = Kleemannia tenella (Berlese, 1916); Ameroseius lanceosetis Livshits & Mitrofanov, 1975 = Kleemannia pavida (C. L. Koch, 1839); Ameroseius marginalis Fan & Li, 1993 and Ameroseius sichuanensis Fan & Li, 1993 = Kleemannia insignis (Bernhard, 1963); Ameroseius pseudofurcatus Livshits & Mitrofanov, 1975 = Ameroseius furcatus Karg, 1971; Ameroseius stramenis Karg, 1976 and Lasioseius (Lasioseius) gracilis Halbert, 1923 = Kleemannia delicata (Berlese, 1918); Epicriopsis langei Livshits & Mitrofanov, 1975 and Epicriopsis baloghi Kandil, 1978 = Epicriopsis palustris Karg, 1971; Epicriopsis rivus Karg, 1971 = Epicriopsis mirabilis Willmann, 1956; Neocypholaelaps ewae Haitlinger, 1987 = Neocypholaelaps indicus Evans, 1963; Neocypholaelaps lindquisti Prasad, 1968, Afrocypholaelaps ranomafanaensis Haitlinger, 1987 and Afrocypholaelaps analicullus Ho, Ma, Wang & Severinghaus, 2010 = Afrocypholaelaps africanus (Evans, 1963); Sinoseius pinnatus Huhta & Karg, 2010 = Sinoseius lobatus Bai, Gu & Fang, 1995. Ameroseius womersleyi Mašán, is a replacement name proposed for Ameroseius ornatus Womersley, 1956, a junior secondary homonym of Cornubia ornata Turk, 1943 [= Ameroseius corbiculus (Sowerby, 1806)]. Cornubia georgei Turk, 1943 is removed from synonymy with Ameroseius corbiculus (Sowerby, 1806). An annotated catalogue of the world species of Ameroseiidae is provided, partly based on type (in more than 60 species) and non-type specimens from various museum deposits and personal collections, including new or revised material from Slovakia. It contains 206 named species (138 valid species, 37
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A revision of the family Ameroseiidae (Acari, Mesostigmata, with some data on Slovak fauna
Directory of Open Access Journals (Sweden)
Peter Mašán
2017-09-01
, 1918 = Kleemannia plumosa (Oudemans, 1902; Ameroseius eumorphus Bregetova, 1977 and Kleemannia potchefstroomensis Kruger & Loots, 1980 = Kleemannia pseudoplumosa (Rack, 1972; Ameroseius gilarovi Petrova, 1986 = Kleemannia plumigera Oudemans, 1930; Ameroseius imparsetosus Westerboer, 1963 = Ameroseius georgei (Turk, 1943; Ameroseius lanatus Solomon, 1969 and Ameroseius fimetorum Karg, 1971 = Kleemannia tenella (Berlese, 1916; Ameroseius lanceosetis Livshits & Mitrofanov, 1975 = Kleemannia pavida (C. L. Koch, 1839; Ameroseius marginalis Fan & Li, 1993 and Ameroseius sichuanensis Fan & Li, 1993 = Kleemannia insignis (Bernhard, 1963; Ameroseius pseudofurcatus Livshits & Mitrofanov, 1975 = Ameroseius furcatus Karg, 1971; Ameroseius stramenis Karg, 1976 and Lasioseius (Lasioseius gracilis Halbert, 1923 = Kleemannia delicata (Berlese, 1918; Epicriopsis langei Livshits & Mitrofanov, 1975 and Epicriopsis baloghi Kandil, 1978 = Epicriopsis palustris Karg, 1971; Epicriopsis rivus Karg, 1971 = Epicriopsis mirabilis Willmann, 1956; Neocypholaelaps ewae Haitlinger, 1987 = Neocypholaelaps indicus Evans, 1963; Neocypholaelaps lindquisti Prasad, 1968, Afrocypholaelaps ranomafanaensis Haitlinger, 1987 and Afrocypholaelaps analicullus Ho, Ma, Wang & Severinghaus, 2010 = Afrocypholaelaps africanus (Evans, 1963; Sinoseius pinnatus Huhta & Karg, 2010 = Sinoseius lobatus Bai, Gu & Fang, 1995. Ameroseius womersleyi Mašán, is a replacement name proposed for Ameroseius ornatus Womersley, 1956, a junior secondary homonym of Cornubia ornata Turk, 1943 [= Ameroseius corbiculus (Sowerby, 1806]. Cornubia georgei Turk, 1943 is removed from synonymy with Ameroseius corbiculus (Sowerby, 1806. An annotated catalogue of the world species of Ameroseiidae is provided, partly based on type (in more than 60 species and non-type specimens from various museum deposits and personal collections, including new or revised material from Slovakia. It contains 206 named species (138 valid species, 37 synonyms, nine