rickettsiella phytoseiuli and virus-like particles in phytosfiulus persimilis (gamasoidea: phytoseiidae) mites.electron microscope investigation of tissue of phytoseiulus persimilis mites revealed its double infection with rickettsiella phytoseiuli and virus-like particles. the presence of rickettsiae in tissues of the mite seemed to be decisive for establishment of virus infection.197829476
experimental infection with rickettsiella phytoseiuli in adult female dermacentor reticulatus (ixodidae): an electron microscopy study.rickettsiella phytoseiuli naturally occurring in phytoseiulus persimilis mites was cultivated in adult female dermacentor reticulatus ticks. it demonstrates all six known developmental stages: dense, intermediate, bacterial, giant, crystal-forming and small dark particles. these stages of rickettsiae were found in salivary glands, malpighian tubules, synganglion, ovaries, tracheal complex, haemolymph, fat body and alimentary tract. rickettsiella phytoseiuli did not infect the gené's organ. it mu ...19892806015
electron microscopic study of developmental stages of rickettsiella phytoseiuli in phytoseiulus persimilis athias-henriot (gamasoidea:phytoseiidae) mites.rickettsiella phytoseiuli was found in great amounts in all tissues except of the nervous system of adult phytoseiulus persimilis mites. six morphologically different stages (dense, intermediate, bacterial, giant, crystal-forming and small dark particles) of r. phytoseiuli were detected. no rickettsiae were seen in the larvae and in phase 1 and 2 nymphae of these mites.19882897771
attempt to cultivate rickettsiella phytoseiuli in dermacentor reticulatus ticks: an electron microscopic study.rickettsiella phytoseiuli occurring in phytoseiulus persimilis mites was cultivated in dermacentor reticulatus ticks. rickettsiella multiplied similarly as in mites exerting all six developmental stages: dense, intermediate, bacterial, giant, crystal-forming and small dark particles.19882897779
the feeding behaviour of phytoseiulus persimilis (acarina: phytoseiidae), particularly as affected by certain pesticides. 19734747045
life history and life table of phytoseiulus persimilis athias-henriot. 19685716483
the influence of humidity on the activity of phytoseiulus persimilis athias-henriot and its prey, tetranychus urticae (c. l. koch) (acarina: phytoseidae, tetranychidae). 19665919297
phenomenon of rickettsiella phytoseiuli in phytoseiulus persimilis unknown microorganism occurring in a predaceous mite phytoseiulus persimilis was described by the author in 1977 as a new species rickettsiella phytoseiuli. some new results on the relation between this agent and its hosts are presented in this paper.19947866725
differential effects of plant species on a mite pest (tetranychus utricae) and its predator (phytoseiulus persimilis): implications for biological control.the influence of plant species on the population dynamics of the spider mite pest, tetranychus urticae, and its predator, phytoseiulus persimilis, was examined as a prerequisite to effective biological control on ornamental nursery stock. experiments have been done to investigate how the development, fecundity and movement of t. urticae, and the movement of p. persimilis were affected by plant species. a novel experimental method, which incorporates plant structure, was used to investigate the f ...199910466216
photographic sampling: a photographic sampling method for mites on plants.a photographic sampling method for mites on plants was evaluated using tetranychus urticae and phytoseiulus persimilis on pepper plants. it was found to be 92% accurate for t. urticae eggs and 98% accurate for p. persimilis eggs at densities up to 45 eggs per cm2 for t. urticae, and up to 3 eggs per cm2 for p. persimilis. the motiles of the two species were not confused, nor were they confused with exuviae or other matter.200010823357
development and pathology of two undescribed species of microsporidia infecting the predatory mite, phytoseiulus persimilis athias-henriot.two undescribed species of microsporidia were found in mass-reared phytoseiulus persimilis athias-henriot from two commercial sources during a routine examination of these predators for pathogens. both microsporidian species were described from specimens that had been prepared for transmission electron microscopy; live specimens were unavailable for examination. one microsporidium, identified as species a, was described from two specimens obtained from a commercial insectary in north america. al ...200011112375
do herbivore-induced plant volatiles influence predator migration and local dynamics of herbivorous and predatory mites?if predators lack information on the prey's position, prey have more chance to escape predation and will therefore reach higher population densities. one of the many possible cues that predators may use to find their prey are herbivore-induced plant volatiles. although their effects on the behaviour of foraging predators have been well studied, little is known about how these prey-related odours affect predator-prey dynamics on a plant. we hypothesise that herbivore-induced plant volatiles provi ...200011156167
process of egg formation in the female body cavity and fertilization in male eggs of phytoseiulus persimilis (acari: phytoseiidae).the process of egg formation in the body cavity of a phytoseiid mite, phytoseiulus persimilis, was observed to examine fertilization of male eggs. after insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. after the egg became filled with yolk granules the two pronuclei fused. the egg moved via the narrow entrance at the ventral region into th ...200011156168
plant species modifies the functional response of phytoseiulus persimilis (acari: phytoseiidae) to tetranychus urticae (acari: tetranychidae): implications for biological control.the functional response of the predatory mite phytoseiulus persimilis athias-henriot to eggs of its prey, the spider mite tetranychus urticae koch was examined on three plant species. experiments were done to determine whether differences in the functional response on the three plant species were due to the morphological features of the crop directly on the predator or through an effect of the plant species on the prey. the results show that crop morphology is the only factor influencing the pre ...200111228589
toxicity of the herbicide glufosinate-ammonium to predatory insects and mites of tetranychus urticae (acari: tetranychidae) under laboratory conditions.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 spec ...200111233107
disease prevalence and transmission of microsporidium phytoseiuli infecting the predatory mite, phytoseiulus persimilis (acari: phytoseiidae).isolated colonies of the predatory mite, phytoseiulus persimilis, were used to gain information regarding prevalence and transmission of microsporidium phytoseiuli. two colonies of p. persimilis were reared on spider mite (tetranychus urticae)-infested bean plants in isolated cages. disease prevalence of predators from colony 1 remained relatively low (between 0 and 15%) over 57 weeks of observation whereas disease prevalence of predators from colony 2 increased over 3 months (from 12 to 100%). ...200111273691
how predatory mites learn to cope with variability in volatile plant signals in the environment of their herbivorous prey.when the chemical cues co-occurring with prey vary in time and space, foraging predators profit from an ability to repeatedly associate chemical cues with the presence of their prey. we demonstrate the ability of a predatory arthropod (the plant-inhabiting mite, phytoseiulus persimilis) to learn the association of a positive stimulus (herbivorous prey, tetranychus urticae) or a negative stimulus (hunger) with a chemical cue (herbivore-induced plant volatiles or green leaf volatiles). it has been ...200011354616
comparison of cultivars of ornamental crop gerbera jamesonii on production of spider mite-induced volatiles, and their attractiveness to the predator phytoseiulus persimilis.we investigated whether volatiles produced by spider mite-damaged plants of four gerbera cultivars differ in attractiveness to phytoseiulus persimilis, a specialist predator of spider mites, and how the mite-induced odor blends differ in chemical composition. the gerbera cultivars differed in resistance, as expressed in terms of spider mite intrinsic rate of population increase (rm). in order of increasing resistance these were sirtaki, rondena, fame, and bianca. to correct for differences in da ...200111504033
integrated pest management of two-spotted mite tetranychus urticae on greenhouse roses using petroleum spray oil and the predatory mite phytoseiulus persimilis.from 1995 to 1999, four experiments were conducted on greenhouse roses to assess the effectiveness of the nc24 petroleum spray oil (pso), d-c-tron plus, against two-spotted mite, tetranychus urticae koch (acarina: tetranychidae), and to determine how the oil could be most efficiently and effectively used in combination with the predatory mite phytoseiulus persimilis athias-henriot (acarina: phytoseiidae) in an integrated pest management program. the results showed that 0.5% pso applied fortnight ...200111508528
jerking in predaceous mites (acari: phytoseiidae) with emphasis on larvae.jerking, a behavior involving a pronounced and often repeated lunging of the body, was studied in larvae among seven species of phytoseiid mites, euseius finlandicus, galendromus occidentalis, neoseiulus californicus, neoseulus fallacis, phytoseiulus macropilis, phytoseiulus persimilis and typhlodromus pyri, and in the nymphal stages of n. fallacis. this behavior was observed in larvae of six of the seven species and in all active immature stages of n. fallacis. jerking was usually triggered by ...200111697785
exogenous acc enhances volatiles production mediated by jasmonic acid in lima bean leaves.we report the synergistic effects of exogenous 1-aminocyclopropane-1-carboxylic acid (acc) and jasmonic acid (ja) on production of induced volatiles by excised lima bean leaves. application of acc alone to leaves induced trace amounts of volatiles. acc positively affected three ja-induced volatiles, (e)- and (z)-beta-ocimene, and (z)-3-hexenyl acetate. the ethylene inhibitor, silver thiosulfate, inhibited the production of these compounds. the results suggest synergistic effects of ja and acc on ...200111741612
population dynamics of interacting predatory mites, phytoseiulus persimilis and neoseiulus californicus, held on detached bean leaves.the success of combined release of the predatory mites phytoseiulus persimilis and neoseiulus californicus in suppression of spider mites may be related to the effects of the interactions between the two predators on their population dynamics. we studied population growth and persistence of the specialist p persimilis and the generalist n. californicus reared singly versus reared in combination after simultaneous and successive predator introductions on detached bean leaf arenas with abundant pr ...200112206584
genetic variation in foraging traits among inbred lines of a predatory mite.response of predators to herbivore-induced plant volatiles can affect the length of time a predator spends in a prey patch and the probability of a predator finding a new prey patch. variation in response to herbivore-induced plant volatiles may lead to different foraging decisions among individuals, thereby affecting both within-patch dynamics and between-patch dispersal. we found significant phenotypic and additive genetic variation in two behavioral assays of response to herbivore-induced pla ...200212399996
prey preference, intraguild predation and population dynamics of an arthropod food web on plants.the theory of intraguild predation (igp) largely studies effects on equilibrium densities of predators and prey, while experiments mostly concern transient dynamics. we studied the effects of an intraguild (ig) predator, the bug orius laevigatus, on the population dynamics of ig-prey, the predatory mite phytoseiulus persimilis, and a shared prey, the phytophagous two-spotted spider mite tetranychus urticae, as well as on the performance of cucumber plants in a greenhouse. the interaction of the ...200112455871
which predatory mite can control both a dominant mite pest, tetranychus urticae, and a latent mite pest, eotetranychus asiaticus, on strawberry?after biological control of tetranychus urticae using phytoseiulus persimilis, a latent mite pest, eotetranychus asiaticus, was found on strawberries growing in a plastic greenhouse in western japan. to determine whether the release of p. persimilis, an exotic natural enemy of t. urticae, enhanced the occurrence of the latent pest, the efficiency of p. persimilis in controlling e. asiaticus was compared with the efficiency of two indigenous phytoseiid mites, amblyseius californicus and a. womers ...200212542009
plant feeding by a predatory mite inhabiting cassava.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 m ...200212593510
the effect of chrysanthemum leaf trichome density and prey spatial distribution on predation of tetranychus urticae (acari: tetranychidae) by phytoseiulus persimilis (acari: phytoseiidae).the effect of plant architecture, in terms of leaf hairiness, and prey spatial arrangement, on predation rate of eggs of the spider mite, tetranychus urticae koch, by the predatory mite phytoseiulus persimilis athias-henriot was examined on cut stems of chrysanthemums. three levels of leaf hairiness (trichome density) were obtained using two different chrysanthemum cultivars and two ages within one of the cultivars. the number of prey consumed by p. persimilis was inversely related to trichome d ...200312908920
interactions in a tritrophic acarine predator-prey metapopulation system v: within-plant dynamics of phytoseiulus persimilis and tetranychus urticae (acari: phytoseiidae, tetranychidae).to investigate the relative contributions of bottom-up (plant condition) and top-down (predatory mites) factors on the dynamics of the two-spotted spider mite (tetranychus urticae), a series of experiments were conducted in which spider mites and predatory mites were released on bean plants. plants inoculated with 2, 4, 8, 16, and 32 adult female t. urticae were either left untreated or were inoculated with 3 or 5 adult female predators (phytoseiulus persimilis) one week after the introduction o ...200314580059
state-dependent and odor-mediated anemotactic responses of a micro-arthropod on a novel type of locomotion compensator.a novel type of locomotion compensator was designed and tested for its use in orientation behavior experiments with a predatory mite. in this apparatus, displacements of the test animal in the two-dimensional plane are recorded using video equipment and a servosphere that keeps the animal in focus. the x and y displacements are registered using two rotation encoders and are compensated using a pair of servo-motors, in such a way that the animal is always positioned on top of the sphere, yet move ...200314587557
the effect of temperature on the functional response of phytoseiulus persimilis (acari: phytoseiidae).environmental variables, such as temperature, are important in determining the efficiency of biological control in ornamental crops. this paper examines the effect of temperature on the functional response of adult female phytoseiulus persimilis to eggs of the spider mite, tetranychus urticae. the functional response was determined using a new functional response assay technique with plant stems as an arena, rather than leaf discs. the use of plant stems allows the influence that plant structure ...200314756399
side-effects of three pesticides on the predatory mite, phytoseiulus persimilis (acari: phytoseiidae).side-effects of three commonly used pesticides in iran were evaluated on an introduced strain of the predatory mite. phytoseiulus persimilis athias-henriot, reared for about 10 years without exposure to any pesticides. application of pesticides was carried out either to detached bean leaves using a potter tower at 1 mg wet deposit per cm2 or by a hand sprayer on bean plants until run off. according to an eppo decision making scheme, pirimiphos-methyl was found to be harmful (e=90.8%) and hepteno ...200314756400
induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation.jasmonic acid (ja) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. in this study, the herbivorous mite, tetranychus urticae, and its predator, phytoseiulus persimilis, were given a choice between lima bean plants induced by ja or spider mites and uninduced control plants. infestation densities resulting in the induction of predator attractants were much lower than thus far assumed, i.e., predatory mites were significantly attracted to plants ...200314969353
differential timing of spider mite-induced direct and indirect defenses in tomato plants.through a combined metabolomics and transcriptomics approach we analyzed the events that took place during the first 5 d of infesting intact tomato (lycopersicon esculentum) plants with spider mites (tetranychus urticae). although the spider mites had caused little visible damage to the leaves after 1 d, they had already induced direct defense responses. for example, proteinase inhibitor activity had doubled and the transcription of genes involved in jasmonate-, salicylate-, and ethylene-regulat ...200415122016
phytoseiid mites in protected crops: the effect of humidity and food availability on egg hatch and adult life span of iphiseius degenerans, neoseiulus cucumeris, n. californicus and phytoseiulus persimilis (acari: phytoseiidae).the effect of relative humidity on egg hatch success for iphiseius degenerans, neoseiulus californicus and n. cucumeris was described by a binomial model with a parallel slope. the shape of the response differed for phytoseiulus persimilis and a model with separate parameters gave a significantly better fit. fitted response curves showed that i. degenerans, n. cucumeris, n. californicus and p. persimilis were ranked by decreasing tolerance to low humidity, with egg mortalities of < 0.5, 3, 12 an ...200415139268
control of the two-spotted spider mite (tetranychus urticae koch) in glasshouse roses.populations of the two-spotted spider mite, tetranychus urticae, can increase rapidly in glasshouse production, especially during summer. both chemical and biological control must start at low densities for effective control. the combined efficacy of phytoseiulus persimilis and the predatory midge, feltiella acarisuga to control t. urticae on roses was evaluated in 2002. a second year rose crop (rosa hybrida cv. first red) was used for this experiment. two glasshouse compartments of 200 m2 each ...200315149115
toxicity of plant essential oils to tetranychus urticae (acari: tetranychidae) and phytoseiulus persimilis (acari: phytoseiidae).fifty-three plant essential oils were tested for their toxicity against eggs and adults of tetranychus urticae koch as well as adults of phytoseiulus persimilis athias-henriot, by using a filter paper diffusion bioassay without allowing direct contact. responses varied according to oil type and dose, and mite species. in a plastic container (4.5 by 9.5 cm) bioassay at 14 x 10(-3) microl/ml air, caraway seed, citronella java, lemon eucalyptus, pennyroyal, and peppermint oils gave > 90% mortality ...200415154481
state-dependent and odour-mediated anemotactic responses of the predatory mite phytoseiulus persimilis in a wind tunnel.anemotaxis in the predatory mite phytoseiulus persimilis (both well-fed and starved), has previously been studied on a wire grid under slight turbulent airflow conditions yielding weak, yet distinct, gradients in wind speed and odour concentration (sabelis and van der weel 1993). such conditions might have critically influenced the outcome of the study. we repeated these experiments, under laminar airflow conditions on a flat surface in a wind tunnel, thereby avoiding variation in wind speed and ...200415176731
negative evidence of wolbachia in the predaceous mite phytoseiulus persimilis.the cytoplasmically inherited bacterium wolbachia is widespread in arthropod species and has been repeatedly detected in the predaceous mite phytoseiulus persimilis. our original goal was to assess the prevalence of wolbachia infection in p. persimilis and the potential fitness consequences for this host. to accomplish that goal, seven p. persimilis strains were obtained from europe, africa and the usa and reared on the phytophagous mite tetranychus urticae as prey. after preliminary results sho ...200516132739
genetic engineering of terpenoid metabolism attracts bodyguards to arabidopsis.herbivore-damaged plants release complex mixtures of volatiles that attract natural enemies of the herbivore. to study the relevance of individual components of these mixtures for predator attraction, we manipulated herbivory-induced volatiles through genetic engineering. metabolic engineering of terpenoids, which dominate the composition of many induced plant volatile bouquets, holds particular promise. by switching the subcellular localization of the introduced sesquiterpene synthase to the mi ...200516179482
induced production of extrafloral nectar in intact lima bean plants in response to volatiles from spider mite-infested conspecific plants as a possible indirect defense against spider mites.we found that intact lima bean plants increased the secretion of extrafloral nectar (efn) after exposure to tetranychus urticae-induced plant volatiles. predatory mites, phytoseiulus persimilis, dispersed more slowly from an exposed intact plant than from a control plant (plant exposed to volatiles from intact conspecific). the predators also dispersed more slowly from those plants that were provided with extra efn than from untreated plants. we further show that efn was a potential alternative ...200616341892
acaricomes phytoseiuli gen. nov., sp. nov., isolated from the predatory mite phytoseiulus persimilis.a gram-positive, rod-shaped, non-spore-forming bacterium, strain csct, was isolated from diseased, surface-sterilized specimens of the predatory mite phytoseiulus persimilis athias-henriot and subjected to polyphasic taxonomic analysis. comparative analysis of the 16s rrna gene sequence revealed that the strain was a new member of the family micrococcaceae. nearest phylogenetic neighbours were determined as renibacterium salmoninarum (94.0%), arthrobacter globiformis (94.8%) and arthrobacter rus ...200616449459
the effect of indoxacarb and five other insecticides on phytoseiulus persimilis (acari: phytoseiidae), amblyseius fallacis (acari: phytoseiidae) and nymphs of orius insidiosus (hemiptera: anthocoridae).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 ve ...200616493722
intraguild interactions between the predatory mites neoseiulus californicus and phytoseiulus persimilis.species at the same trophic level may interact through competition for food, but can also interact through intraguild predation. intraguild predation is widespread at the second and third trophic level and the effects may cascade down to the plant level. the effects of intraguild predation can be modified by antipredator behaviour in the intraguild prey. we studied intraguild predation and antipredator behaviour in two species of predatory mite, neoseiulus californicus and phytoseiulus persimili ...200616550333
the effects of prey patchiness, predator aggregation, and mutual interference on the functional response of phytoseiulus persimilis feeding on tetranychus urticae (acari: phytoseiidae, tetranychidae).the spatial distributions of two-spotted spider mites tetranychus urticae and their natural enemy, the phytoseiid predator phytoseiulus persimilis, were studied on six full-grown cucumber plants. both mite species were very patchily distributed and p. persimilis tended to aggregate on leaves with abundant prey. the effects of non-homogenous distributions and degree of spatial overlap between prey and predators on the per capita predation rate were studied by means of a stage-specific predation m ...200616596345
testing for non-target effects of spinosad on twospotted spider mites and their predator phytoseiulus persimilis under greenhouse conditions.the compatibility of the selective insecticide spinosad (conserve sc), at rates recommended for thrips control in greenhouses, with release of the predatory mite phytoseiulus persimilis athias-henriot (acari: phytoseiidae) to control spider mites, was investigated in a crop of ivy geranium pelargonium peltatum, cultivar 'amethyst 96.' plants were inoculated with twospotted spider mites, tetranychus urticae koch (acari: tetranychidae), 2 weeks before treatments were applied. there were three trea ...200616596348
a novel disease affecting the predatory mite phytoseiulus persimilis (acari, phytoseiidae): 1. symptoms in adult female phytoseiulus persimilis athias-henriot (acari, phytoseiidae) of one of our laboratory populations showed a lower degree of attraction to herbivore-induced plant volatiles than other laboratory populations. we hypothesized earlier that this consistent change in foraging behavior is a symptom of a disease, as it is a contagious phenomenon. here we describe more symptoms by comparing mated females of this population (non-responding (nr) population) with mated females of other populatio ...200616612670
the predatory mite phytoseiulus persimilis adjusts patch-leaving to own and progeny prey needs.integration of optimal foraging and optimal oviposition theories suggests that predator females should adjust patch leaving to own and progeny prey needs to maximize current and future reproductive success. we tested this hypothesis in the predatory mite phytoseiulus persimilis and its patchily distributed prey, the two-spotted spider mite tetranychus urticae. in three separate experiments we assessed (1) the minimum number of prey needed to complete juvenile development, (2) the minimum number ...200616680562
a novel disease affecting the predatory mite phytoseiulus persimilis (acari, phytoseiidae): 2. disease transmission by adult female phytoseiulus persimilis athias-henriot (acari, phytoseiidae) of one of our laboratory populations (=nr-population), show the following set of symptoms: predators shrink several days after mating, cease egg production and die several days after shrinking, show a lower degree of attraction to herbivore-induced plant volatiles and a shorter choice time in olfactometer tests, have the tendency to leave a prey patch with ample food, may carry excretory crystals in the legs, may cease pre ...200616724162
comparison of single and combination treatments of phytoseiulus persimilis, neoseiulus californicus, and acramite (bifenazate) for control of twospotted spider mites in strawberries.greenhouse and field experiments were conducted from 2003 to 2005 to determine the effectiveness of combining releases of two predatory mite species, phytoseiulus persimilis athias-henriot and neoseiulus californicus (mcgregor), and a reduced-risk miticide, acramite (bifenazate), for control of twospotted spider mite (tssm) (tetranychus urticae koch) in strawberries. in the greenhouse experiment, a combination treatment of p. persimilis and n. californicus was compared with single treatments of ...200616770685
predator avoidance in phytophagous mites: response to present danger depends on alternative host quality.we studied whether volatiles released by putative host plants affect the antipredator response of an herbivorous mite, tetranychus urticae, when the patch was invaded by phytoseiulus persimilis. tetranychus urticae laid a lower number of eggs on tomato leaves than on lima bean leaves, suggesting that lima bean is a preferred host food source for t. urticae. in addition, t. urticae preferred lima bean plant volatiles to tomato plant volatiles in a y-tube olfactometer test. to investigate the anti ...200717102994
efficacy and persistence of rosemary oil as an acaricide against twospotted spider mite (acari: tetranychidae) on greenhouse tomato.efficacy of rosemary, rosmarinus officinalis l., essential oil was assessed against twospotted spider mite, tetranychus urticae koch (acari: tetranychidae), as well as effects on the tomato, lycopersicum esculatum mill., host plant and biocontrol agents. laboratory bioassay results indicated that pure rosemary oil and ecotrol (a rosemary oil-based pesticide) caused complete mortality of spider mites at concentrations that are not phytotoxic to the host plant. the predatory mite phytoseiulus pers ...200617195668
whole genome amplification of chelex-extracted dna from a single mite: a method for studying genetics of the predatory mite phytoseiulus persimilis.we developed and optimized a method using chelex dna extraction followed by whole genome amplification (wga) to overcome problems conducting molecular genetic studies due to the limited amount of dna obtainable from individual small organisms such as predatory mites. the dna from a single mite, phytoseiulus persimilis athias-henrot (acari: phytoseiidae), isolated in chelex suspension was subjected to wga. more than 1000-fold amplification of the dna was achieved using as little as 0.03 ng genomi ...200717237968
evaluation of predatory mites and acramite for control of twospotted spider mites in strawberries in north central florida.greenhouse and field experiments were conducted from 2003 to 2005 to determine the effectiveness of two predatory mite species, phytoseiulus persimilis athias-henriot and neoseiulus californicus (mcgregor), and a reduced-risk miticide, acramite 50 wp (bifenazate), for control of twospotted spider mite, tetranychus urticae koch, in strawberries (fragaria x ananassa duchesne). in greenhouse tests, three treatments consisting of releases of p. persimilis, n. californicus, and an untreated control w ...200616937684
amblyseius andersoni chant (acari: phytoseiidae), a successful predatory mite on rosa spp.roses on commercial nurseries commonly suffer from attacks by the two-spotted spider mite, tetranychus urticae, which have a negative influence on growth and quality. the aim of this project is to find natural enemies that are well adapted to roses, and may improve biological control. at different sites such as a plant collection garden, public parks and field boundaries, leaves were sampled from roses to identify the indigenous species of predatory mites. amblyseius andersoni was amongst other ...200415759407
ozone degrades common herbivore-induced plant volatiles: does this affect herbivore prey location by predators and parasitoids?inducible terpenes and lipoxygenase pathway products, e.g., green-leaf volatiles (glvs), are emitted by plants in response to herbivory. they are used by carnivorous arthropods to locate prey. these compounds are highly reactive with atmospheric pollutants. we hypothesized that elevated ozone (o(3)) may affect chemical communication between plants and natural enemies of herbivores by degrading signal compounds. in this study, we have used two tritrophic systems (brassica oleracea-plutella xylost ...200717333375
ige-sensitization to predatory mites and respiratory symptoms in swedish greenhouse workers.predatory mites are used as biological pesticides worldwide for control of spider mites and other pests in greenhouses. the aim of this study was to evaluate the impact of occupational exposure to phytoseiulus persimilis and hypoaspis miles on ige sensitization among a large group of swedish greenhouse workers and to examine the relationship between exposure and allergic asthma and rhinoconjunctivitis.200515727587
identification of volatiles that are used in discrimination between plants infested with prey or nonprey herbivores by a predatory mite.carnivorous arthropods can use herbivore-induced plant volatiles to locate their herbivorous prey. in the field, carnivores are confronted with information from plants infested with herbivores that may differ in their suitability as prey. discrimination by the predatory mite phytoseiulus persimilis between volatiles from lima bean plants infested with the prey herbivore tetranychus urticae, or plants infested with the nonprey caterpillar spodoptera exigua, depends on spider mite density. in this ...200415672666
ontogenetic shifts in intraguild predation on thrips by phytoseiid mites: the relevance of body size and diet greenhouse agroecosystems, a guild of spider mite predators may consist of the oligophagous predatory mite phytoseiulus persimilis athias-henriot, the polyphagous predatory mite neoseiulus californicus mcgregor (both acari: phytoseiidae) and the primarily herbivorous but facultatively predatory western flower thrips frankliniella occidentalis pergande (thysanoptera: thripidae). diet-specialization and the predator body size relative to prey are crucial factors in predation on f. occidentalis ...200415541196
exposure of lima bean leaves to volatiles from herbivore-induced conspecific plants results in emission of carnivore attractants: active or passive process?there is increasing evidence that volatiles emitted by herbivore-damaged plants can cause responses in downwind undamaged neighboring plants, such as the attraction of carnivorous enemies of herbivores. one of the open questions is whether this involves an active (production of volatiles) or passive (adsorption of volatiles) response of the uninfested downwind plant. this issue is addressed in the present study. uninfested lima bean leaves that were exposed to volatiles from conspecific leaves i ...200415503521
jasmonic acid is a key regulator of spider mite-induced volatile terpenoid and methyl salicylate emission in tomato.the tomato (lycopersicon esculentum) mutant def-1, which is deficient in induced jasmonic acid (ja) accumulation upon wounding or herbivory, was used to study the role of ja in the direct and indirect defense responses to phytophagous mites (tetranychus urticae). in contrast to earlier reports, spider mites laid as many eggs and caused as much damage on def-1 as on wild-type plants, even though def-1 lacked induction of proteinase inhibitor activity. however, the hatching-rate of eggs on def-1 w ...200415310835
the relationship between dietary specialism and availability of food and water on cannibalistic interactions among predatory mites in protected crops.the interplay between dietary specialism, the tolerance of food and water stress and level of cannibalism is likely to be important in determining the outcome of biological control using inundative releases of multiple natural enemies, such as phytoseiid mites in protected crops. the dietary specialist, phytoseiulus persimilis, with a short immature development time (4-5 days) when plentiful food was available had a low ability to survive without food (5 days), even with access to water. the die ...200415285136
multiple displacement amplification in combination with high-fidelity pcr improves detection of bacteria from single females or eggs of metaseiulus occidentalis (nesbitt) (acari: phytoseiidae).amplifying microbial dna by the polymerase chain reaction (pcr) from single phytoseiid mites has been difficult, perhaps due to the low titer of bacteria and to interference by the relatively larger amounts of mite genomic dna. in this paper we evaluate the efficiency of standard and high-fidelity pcr protocols subsequent to amplification of the whole genome by a multiple displacement amplification (mda) procedure developed by dean et al. dna from the phytoseiid phytoseiulus persimilis (athias-h ...200415261775
the role of methyl salicylate in prey searching behavior of the predatory mite phytoseiulus persimilis.many carnivorous arthropods use herbivore-induced plant volatiles to locate their prey. these plant volatiles are blends of up to hundreds of compounds. it is often unknown which compounds in such a complex volatile blend represent the signal to the foraging carnivore. we studied the role of methyl salicylate (mesa) as part of the volatile blend in the foraging behavior of the predatory mite phytoseiulus persimilis by using a y-tube olfactometer. mesa is one of the compounds released by lima bea ...200415112723
ige-mediated sensitization to predatory mites in swedish greenhouse workers.predatory mites are used as biological pesticides worldwide for control of spider mites and other pests in greenhouses. the aim of this study was to investigate if predatory and spider mites give rise to sensitization among greenhouse workers who use biological pesticides.200312708983
predatory mite attraction to herbivore-induced plant odors is not a consequence of attraction to individual herbivore-induced plant volatiles.predatory mites locate herbivorous mites, their prey, by the aid of herbivore-induced plant volatiles (hipv). these hipv differ with plant and/or herbivore species, and it is not well understood how predators cope with this variation. we hypothesized that predators are attracted to specific compounds in hipv, and that they can identify these compounds in odor mixtures not previously experienced. to test this, we assessed the olfactory response of phytoseiulus persimilis, a predatory mite that pr ...200818521678
evaluation of dry-adapted strains of the predatory mite neoseiulus californicus for spider mite control on cucumber, strawberry and pepper.the goal of this study was to evaluate spider mite control efficacy of two dry-adapted strains of neoseiulus californicus. performance of these strains were compared to a commercial strain of phytoseiulus persimilis on whole cucumber, pepper and strawberry plants infested with tetranychus urticae at 50 +/- 5% rh. under these dry conditions predators' performance was very different on each host plant. on cucumber, spider mite suppression was not attained by any of the three predators, plants 'bur ...200818566897
fine structure of the female genital system in phytoseiid mites with remarks on egg nutrimentary development, sperm-access system, sperm transfer, and capacitation (acari, gamasida, phytoseiidae).the fine structure of the female genital system is described in two phytoseiid species: phytoseiulus persimilis athias-henriot (mating females) and typhlodromus rhenanoides athias-henriot (overwintering females). the female genital tract is composed of an unpaired gonad, the uterus (oviduct i), and the vaginal duct (oviduct ii). the latter leads to the vagina (genital atrium), into which a pair of vaginal glands opens. the gonad (ovary s.l.) has two components: the ovary (s.str) where germ cells ...200111989482
habitat structure and population persistence in an experimental community.understanding spatial population dynamics is fundamental for many questions in ecology and conservation. many theoretical mechanisms have been proposed whereby spatial structure can promote population persistence, in particular for exploiter-victim systems (host-parasite/pathogen, predator-prey) whose interactions are inherently oscillatory and therefore prone to extinction of local populations. experiments have confirmed that spatial structure can extend persistence, but it has rarely been poss ...200111484053
cannibalism and intraguild predation among phytoseiid mites: are aggressiveness and prey preference related to diet specialization?we tested whether specialist and generalist phytoseiid mites differ in aggressiveness and prey choice in cannibalism and intraguild predation. specialists tested were galendromus occidentalis, neoseiulus longispinosus, phytoseiulus persimilis, and p. macropilis; generalists tested were amblyseius andersoni, euseius finlandicus, e. hibisci, kampimodromus aberrans, neoseiulus barkeri, n. californicus, n. cucumeris, nm fallacis, and typhlodromus pyri. aggressiveness of cannibalistic females against ...200011227828
verified and potential pathogens of predatory mites (acari: phytoseiidae).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 interactions. pathogen-free phytoseiid mites are important to obtain high efficacy in biological pest control and to get reliable data in mite research, as pathogens may affect the performance of their hos ...200818763041
induced response of tomato plants to injury by green and red strains of tetranychus urticae.we studied the induced response of tomato plants to the green strain and the red strain of the spider mite tetranychus urticae. we focused on the olfactory response of the predatory mite phytoseiulus persimilis to volatiles from t. urticae-infested tomato leaves in a y-tube olfactometer. tomato leaves attracted the predatory mites when slightly infested with the red strain, or moderately or heavily infested with the green strain. in contrast, neither leaves that were slightly infested with green ...200011156163
comparative life-history traits of three phytoseiid mites associated with tetranychus urticae (acari: tetranychidae) colonies in clementine orchards in eastern spain: implications for biological control.the management of tetranychus urticae, a key pest of clementine trees, is mainly based on the use of acaricides. however, more environmentally safe measures, such as biological control, are being encouraged. life-history traits of the three most abundant phytoseiid mites associated with t. urticae on this crop (euseius stipulatus, phytoseiulus persimilis and neoseiulus californicus) were studied. the experiments were performed under laboratory conditions (25 degrees c, 80 +/- 5% rh and 16:8 h (l ...200918931925
herbivory-induced volatiles elicit defence genes in lima bean response to herbivore damage, several plant species emit volatiles that attract natural predators of the attacking herbivores. using spider mites (tetranychus urticae) and predatory mites (phytoseiulus persimilis), it has been shown that not only the attacked plant but also neighbouring plants are affected, becoming more attractive to predatory mites and less susceptible to spider mites. the mechanism involved in such interactions, however, remains elusive. here we show that uninfested lima b ...200010952311
sequence variation of ribosomal internal transcribed spacers (its) in commercially important phytoseiidae mites.preliminary work is needed to assess the usefulness of different markers at different taxonomic scales when a new group is analyzed, such as the commercially important phytoseiidae mites. we investigate here the level of sequence variation of the nuclear ribosomal spacers its 1 and 2 and the 5.8s gene in six species of phytoseiidae: neoseiulus culifornicus, n. fallacis, euseius concordis, metaseiulus occidentalis, typhlodromus pyri and phytoseiulus persimilis. as expected, the 5.8s gene (148 bas ...199910668860
birefringent crystals and abdominal discoloration in the predatory mite phytoseiulus persimilis (acari: phytoseiidae)in response to grower complaints of poor performance of phytoseiulus persimilis, mites from 14 commercial insectaries and research colonies were examined for pathogens. some were found to have abdominal discolorations, manifested initially as two white stripes along the dorsal sides of the body within the malpighian tubules. advanced signs appeared as a large, centrally located, white spot or u-shaped discoloration in the distal opisthosoma within the rectum/anal atrium. white material often acc ...19979056458
effect of the entomopathogenic fungus lecanicillium muscariumon the predatory mite phytoseiulus persimilis as a non-target biological control, different benefit organisms have to combine for an effective management. if entomopathogenic fungi will be integrated, than it has to be considered also the effect on non-target organisms like beneficial arthropods. because of the high importance of predatory mite phytoseiulus persimilis in biological control it was to determine side effects of leconicillium muscarium on this species. in two standardised biotests in petri dish and on plants (p. vulgaris) individuals were d ...200819226778
comparing chemical and biological control strategies for twospotted spider mites (acari: tetranychidae) in commercial greenhouse production of bedding plants.efficacy, costs, and impact on crop salability of various biological and chemical control strategies for tetranychus urticae koch (acari: tetranychidae) were evaluated on mixed plantings of impatiens, impatiens wallerana hook.f (ericales: balsaminaceae), and ivy geranium, pelargonium peltatum (1.) l'hér. ex aiton (geraniales: geraniaceae), cultivars in commercial greenhouses. chemical control consisting of the miticide bifenazate (floramite) was compared with two biological control strategies us ...200919253653
intraguild interactions between euseius stipulatus and the candidate biocontrol agents of tetranychus urticae in spanish clementine orchards: phytoseiulus persimilis and neoseiulus californicus.spanish clementine orchards are frequently infested by the two-spotted spider mte tetranychus urticae. natural control of t. urticae is insufficient despite the presence of neoseiulus californicus and phytoseiulus persimilis. the phytoseiid community is dominated by the generalist euseius stipulatus which is poorly adapted to exploit t. urticae. having the intention to promote biological control of t. urticae by augmentative releases we were interested whether p. persimilis and n. californicus a ...201019517257
predation-related odours reduce oviposition in a herbivorous mite.when adult females of the herbivorous mite, tetranychus urticae, were exposed to the predatory mite, phytoseiulus persimilis, they laid fewer eggs than females that had not been exposed to p. persimilis when transferred onto a new leaf patch. however, when t. urticae females were exposed to either products of p. persimilis or artificially damaged conspecific eggs on a leaf patch, the number of t. urticae eggs on a new leaf patch did not differ significantly from the control. the reduced oviposit ...201019526199
on the ultrastructure and functional morphology of the male chelicerae (gonopods) in parasitina and dermanyssina mites (acari: gamasida).males of parasitina and dermanyssina (gamasida=mesostigmata) have chelicerae modified to function as gonopods. the slit-like spermatotreme in the movable digit of the chela in males of parasitina was studied in three species: in pergamasus quisquiliarum and holoparasitus sp. a rather simple slit is indeed present, whereas in vulgarogamasus kraepelini the structure is represented by a fine duct traversing the movable digit. the spermatodactyl studied in two phytoseioid species (phytoseiulus persi ...200919602394
ultrastructure and pathology of microsporidium phytoseiuli n. sp. infecting the predatory mite, phytoseiulus persimilis athias-henriot (acari: phytoseiidae)ultrastructure and pathology of microsporidium phytoseiuli n. sp. infecting the predatory mite phytoseiulus persimilis athias-henriot is described using light and transmission electron microscopy. infected mites showed no gross, external symptoms. all observed stages of the parasite had unpaired nuclei. schizonts were commonly observed within nuclei of digestive cells of the ventriculus and within the cytoplasm of cells lining the cecal wall and in muscle tissue underlying it. sporoblasts and sp ...19968954812
phylogeny of ticks (ixodida) inferred from nuclear ribosomal dna.phylogenetic relationships of 9 species of ticks were inferred from nucleotide sequences of the d1 domain of large subunit ribosomal dna (rdna), the v4 region of small subunit rdna and sequences immediately adjacent to these regions. six of the 7 subfamilies in the argasidae and ixodidae were represented: ornithodorinae and argasinae from the argasidae (soft ticks); and ixodinae, amblyomminae, haemaphysalinae and rhipicephalinae from the ixodidae (hard ticks). a mite, phytoseiulus persimilis, fr ...19968818731
exogenous polyamines elicit herbivore-induced volatiles in lima bean leaves: involvement of calcium, h2o2 and jasmonic acid.we investigated the role of polyamines (pas) in lima bean (phaseolus lunatus) leaves on the production of herbivorous mite (tetranychus urticae)-induced plant volatiles that attract carnivorous natural enemies of the herbivores. to do this, we focused on the effects of the exogenous pas [cadaverine, putrescine, spermidine and spermine (spm)] on the production of volatiles, h(2)o(2) and jasmonic acid (ja) and the levels of defensive genes, cytosolic calcium and reactive oxygen species (ros). amon ...200919884250
pesticides and phytoseiid mites: strategies for risk assessment.laboratory toxicity trials may predict effects of chemicals under field conditions, but errors are inevitable. a chemical may be presumed harmless when in fact it has a detrimental effect, or it may appear highly toxic in the laboratory, but not in the field. error rates depend on experimental setups, evaluation criteria, and ecological attributes, such as dietary range, of the organisms under study. the authors analyze results of standardized toxicity studies of pesticides on four species of pr ...19958565878
[standardization of a rearing procedure of tetranychus urticae koch (acari: tetranychidae) on bean (phaseolus vulgaris): plant age and harvest time].a rearing technique was standardized to produce tetranychus urticae koch on phaseolus vulgaris (ica cerinza variety) as a prey of the predatory mite phytoseiulus persimilis athias-henriot. two assays were conducted to assess the following variables: 1. the most suitable plant age for mite infestation, 2. the best time to harvest the mites and reinfest the plants. in the first experiment, four-, five-, six-, and seven-week-old plants of p. vulgaris were infested with six t. urticae per foliole. t ...200919943015
whiteflies interfere with indirect plant defense against spider mites in lima bean.plants under herbivore attack are able to initiate indirect defense by synthesizing and releasing complex blends of volatiles that attract natural enemies of the herbivore. however, little is known about how plants respond to infestation by multiple herbivores, particularly if these belong to different feeding guilds. here, we report the interference by a phloem-feeding insect, the whitefly bemisia tabaci, with indirect plant defenses induced by spider mites (tetranychus urticae) in lima bean (p ...200919965373
methyl salicylate production in tomato affects biotic interactions.the role of methyl salicylate (mesa) production was studied in indirect and direct defence responses of tomato (solanum lycopersicum) to the spider mite tetranychus urticae and the root-invading fungus fusarium oxysporum f. sp. lycopersici, respectively. to this end, we silenced the tomato gene encoding salicylic acid methyl transferase (samt). silencing of samt led to a major reduction in samt expression and mesa emission upon herbivory by spider mites, without affecting the induced emission of ...201020059742
polyamines and jasmonic acid induce plasma membrane potential variations in lima bean.exogenous polyamines [cadaverine (cad), putrescine (put), spermidine (spd) and spermine (spm)] elicit the production of volatiles in lima bean (phaseolus lunatus). among the tested pas, spm induces the production of some volatile terpenoids that are known to be induced by the spider mite tetranychus urticae. spm treatment elicits the biosynthesis of jasmonic acid (ja), a phytohormone known to regulate the production of the volatile terpenoids. the treatment with ja together with spm resulted in ...201020200489
behavioural response of phytoseiulus persimilisin inert materials for technical application.a large scale application of the predatory mite phytoseiulus persimilis athias-henriot for use in the biological control of spider mites in the field requires testing the behaviour of phytoseiulus persimilis in inert materials, like millet pelts and vermiculite (1-3 mm). in laboratory studies, the distribution of the individuals in such materials, the time of remaining in the material were proved. to examine the abiotic influences on the time of remaining in the material, the dampness of the mat ...200920222596
genetic variation in jasmonic acid- and spider mite-induced plant volatile emission of cucumber accessions and attraction of the predator phytoseiulus persimilis.cucumber plants (cucumis sativus l.) respond to spider-mite (tetranychus urticae) damage with the release of specific volatiles that are exploited by predatory mites, the natural enemies of the spider mites, to locate their prey. the production of volatiles also can be induced by exposing plants to the plant hormone jasmonic acid. we analyzed volatile emissions from 15 cucumber accessions upon herbivory by spider mites and upon exposure to jasmonic acid using gas chromatography-mass spectrometry ...201020383796
antigenic relationship between the house dust mite dermatophagoides farinae and the predacious mite phytoseiulus persimilis.we have examined the antigenic relationship between the house dust mite dermatophagoides farinae and the predacious mite phytoseiulus persimilis. immunoblotting analysis demonstrated that there was a very weak antigenic cross-reactivity between these different suborder of mites but that this cross-reactivity was not attributed to d. farinaes major allergen's, der fi and der fii. these results suggest that p. persimilis might scarcely provoke allergic symptoms in patients sensitized to house dust ...19947887812
morphological and molecular diagnostics of phytoseiulus persimilis and phytoseiulus macropilis (acari: phytoseiidae).this study focuses on the diagnostics of two natural enemy species, belonging to the genus phytoseiulus in the family phytoseiidae (sub-family amblyseiinae): p. macropilis and p. persimilis. these two species are of primary importance in biological control all over the world. however, they are morphologically very similar and specific diagnostics is difficult. this study utilizes mitochondrial molecular markers (12s rrna and cytb mtdna) to differentiate these two species. morphological analyses ...201020473708
response of predatory mites to a herbivore-induced plant volatile: genetic variation for context-dependent behaviour.plants infested with herbivores release specific volatile compounds that are known to recruit natural enemies. the response of natural enemies to these volatiles may be either learned or genetically determined. we asked whether there is genetic variation in the response of the predatory mite phytoseiulus persimilis to methyl salicylate (mesa). mesa is a volatile compound consistently produced by plants being attacked by the two-spotted spider mite, the prey of p. persimilis. we predicted that pr ...201020574785
mitochondrial genome analysis of the predatory mite phytoseiulus persimilis and a revisit of the metaseiulus occidentalis mitochondrial this study we sequenced and analysed the complete mitochondrial (mt) genome of the chilean predatory mite phytoseiulus persimilis athias-henriot (chelicerata: acari: mesostigmata: phytoseiidae: amblyseiinae). the 16 199 bp genome (79.8% at) contains the standard set of 13 protein-coding and 24 rna genes. compared with the ancestral arthropod mtdna pattern, the gene order is extremely reshuffled (35 genes changed position) and represents a novel arrangement within the arthropods. this is proba ...201020616860
the predatory mite phytoseiulus persimilis does not perceive odor mixtures as strictly elemental objects.phytoseiulus persimilis is a predatory mite that in absence of vision relies on the detection of herbivore-induced plant odors to locate its prey, the two-spotted spider-mite tetranychus urticae. this herbivorous prey is feeding on leaves of a wide variety of plant species in different families. the predatory mites respond to numerous structurally different compounds. however, typical spider-mite induced plant compounds do not attract more predatory mites than plant compounds not associated with ...201020872172
new approach for the study of mite reproduction: the first transcriptome analysis of a mite, phytoseiulus persimilis (acari: phytoseiidae).many species of mites and ticks are of agricultural and medical importance. much can be learned from the study of transcriptomes of acarines which can generate dna-sequence information of potential target genes for the control of acarine pests. high throughput transcriptome sequencing can also yield sequences of genes critical during physiological processes poorly understood in acarines, i.e., the regulation of female reproduction in mites. the predatory mite, phytoseiulus persimilis, was select ...201020888830
tri-trophic level impact of host plant linamarin and lotaustralin on tetranychus urticae and its predator phytoseiulus persimilis.the impact of linamarin and lotaustralin content in the leaves of lima beans, phaseolus lunatus l., on the second and third trophic levels was studied in the two-spotted spider mite, tetranychus urticae (koch), and its predator phytoseiulus persimilis athias-henriot. the content of linamarin was higher in terminal trifoliate leaves (435.5 ppm) than in primary leaves (142.1 ppm) of henderson bush lima beans. however, linamarin concentrations were reversed at the second trophic level showing highe ...201020953678
mycorrhiza-induced trophic cascade enhances fitness and population growth of an acarine predator.research on trophic cascades in terrestrial ecosystems has only recently revealed that root-associated organisms interact with organisms living on aboveground plant parts. arbuscular mycorrhizal (am) symbiosis is a ubiquitous phenomenon, yet studies on its effect on aboveground natural enemies of herbivores are scarce and mainly deal with plant-mediated rather than herbivore-mediated interactions. here, we studied herbivore-mediated effects of am symbiosis on an acarine predator. we measured lif ...201021049299
host plant quality, spatial heterogeneity, and the stability of mite predator-prey dynamics.population dynamics models suggest that both the over-all level of resource productivity and spatial variability in productivity can play important roles in community dynamics. higher productivity environments are predicted to destabilize consumer-resource dynamics. conversely, greater heterogeneity in resource productivity is expected to contribute to stability. yet the importance of these two factors for the dynamics of arthropod communities has been largely overlooked. i manipulated nutrient ...201021053057
variation in herbivory-induced volatiles among cucumber (cucumis sativus l.) varieties has consequences for the attraction of carnivorous natural response to herbivory by arthropods, plants emit herbivory-induced volatiles that attract carnivorous enemies of the inducing herbivores. here, we compared the attractiveness of eight cucumber varieties (cucumis sativus l.) to phytoseiulus persimilis predatory mites after infestation of the plants with herbivorous spider mites (tetranychus urticae) under greenhouse conditions. attractiveness differed considerably, with the most attractive variety attracting twice as many predators as the leas ...201121249432
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