| respiratory allergies (bronchial asthma and rhinitis) due to sensitization of type i allergy to red spider mite (panonychus ulmi koch). | the inhabitants of a fruit growing area often report spontaneously of sensitization to the red spider mite (rsm) (panonychus ulmi koch). these are for the most part sensitizations with low clinical symptoms (rhinitis, conjunctivitis and erythema). severe clinical developments with bronchial asthma have been observed. we investigated six patients working in a fruit growing area sensitized by rsm. the sensitizations corresponded to a type i allergy. skin tests and provocation tests (nasal as well ... | 1992 | 1464051 |
| pesticidal activity of virginiamycins s1 and m1. | virginiamycins s1 and m1, two major components of the antibacterial antibiotic complex produced by streptomyces virginiae and used as an animal growth promoter in animal husbandry, exhibited a selective insecticidal activity against leptinotarsa decemlineata comparable with the effect of the organophosphorus pesticide metathion. an acaricidal effect of the two compounds on eggs of tetranychus urticae was also observed. | 1992 | 1493906 |
| ab3217-a, a novel anti-mite substance produced by a strain of streptomyces platensis. | ab3217-a, a novel anti-mite substance, was isolated from the fermentation broth of a streptomycete strain. the strain was isolated from a soil collected at kita-azumi, nagano prefecture, japan, and identified as streptomyces platensis ab3217. ab3217-a was purified by amberlite ir120b, diaion hp-20 and cm-sephadex c-25 column chromatographies. the molecular formula was determined as c17h23no7 by elemental analysis, ms and 13c nmr spectroscopy. the structure of ab3217-a was determined to be (1r,3s ... | 1992 | 1592678 |
| inhibition of atp dephosphorylation by acaricides with emphasis on the anti-atpase activity of the carbodiimide metabolite of diafenthiuron. | 3-(2,6-diisopropyl-4-phenoxyphenyl)-1-tert-butylcarbodiimide (dfcd), a toxic metabolite and photodegradation product of the propesticide diafenthiuron, and dicyclohexylcarbodiimide (dccd), a commonly used biochemical inhibitory probe, inhibited mg(2+)-, na+k(+)-, and ca2+mg(2+)-atpase activities in preparations from bulb mites (rhizoglyphus echinopus (fumouze and robin)), twospotted spider mites (tetranychus urticae koch), and bluegill (lepomis macrochirus rafinesque) brain. dccd was more active ... | 1991 | 1832178 |
| [a comparative study of the effect of vinyl phosphoric acid esters on cholinesterase and carboxylesterase activities in mammals and arthropods]. | studies have been made of the effect of organophosphorus inhibitors on cholinesterase and carboxylesterase from various mammals (human erythrocytes, mouse brain, blood serum of mouse and rat, blood serum of horse) and arthropods (calliphora vicina, schizaphis graminum, myzus persicae, sitophilus oryzae, pseudococcus maritimus, tetranychus urticae). organophosphorus inhibitors were presented by esters of vynylphosphoric acid containing normal and branched alkyls in the phosphoryl part of the mole ... | 1990 | 2360379 |
| syntheses and biological activities of 13-substituted avermectin aglycons. | the reactions of sulfonate esters of the allylic/homoallylic 13-alcohol of 5-o-(tert-butyldimethylsilyl)-22,23-dihydroavermectin b1a aglycon (1a) were investigated. nucleophilic substitution gave 13 beta-chloro and 13 beta-iodo derivatives, while solvolytic reaction conditions yielded 13 alpha-methoxy, 13 alpha-fluoro, and 13 alpha-chloro products. a mixture of 13 alpha- and 13 beta-fluorides was obtained upon reaction with dast. the 13 beta-iodide gave, upon elimination with lutidine, the 8(9), ... | 1989 | 2913297 |
| the influence of humidity on the activity of phytoseiulus persimilis athias-henriot and its prey, tetranychus urticae (c. l. koch) (acarina: phytoseidae, tetranychidae). | | 1966 | 5919297 |
| encounters in predator-prey systems: a simple discrete model. | predator-prey systems are often described by exploitation models. these models can mimic experimental data very accurately, but it is sometimes difficult to realize the relationships between the models and the behavior of individual predator and prey animals. a simple discrete model is proposed here that tries to elucidate the connections between: the animals' movements, the predator/prey encounters; and the dynamics in the system as globally represented by the exploitation models. in these mode ... | 1984 | 6743794 |
| ige-mediated occupational allergy to a spider mite. | two patients who suffered from allergic rhinitis, conjunctivitis and contact urticaria caused by the two-spotted spider mite (tetranychus urticae, koch) are described. both patients worked in a greenhouse where they came in contact with both spider mites and predator mites living on bean leaves. prick, prausnitz-küstner and rast tests indicated type i allergy to spider mite but not to predator mite. both patients had a high level (rast score 4) of spider-mite-specific ige in their sera. radioall ... | 1983 | 6883665 |
| bioproduction of an extract from penicillium funiculosum thom with activity against ceratitis capitata and tetranychus urticae. | the bioproduction conditions of a crude extract from a strain of penicillium funiculosum thom, which shows activity against ceratitis capitata and tetranychus urticae, have been optimized. the efficacy degree was 95% (c. capitata) and 100% (t. urticae), according to abbot. this is the first report on the pesticide activity of an extract from p. funiculosum against these species. the best yields were obtained when p. funiculosum was grown in raulin-thom medium at ph 6.5 with sucrose candy as the ... | 1993 | 7763929 |
| rflp analysis of ribosomal dna in sibling species of spider mite, genus panonychus (acari: tetranychidae). | ribosomal dna (rdna) restriction fragment length of spider mites was analysed in three sibling species of genus panonychus (p. mori, p. citri and p. ulmi) and tetranychus urticae. seventy-one fragments were detected by enhanced chemiluminescence (ecl) after southern hybridization with two genomic rdna probes of mouse. percentages of shared fragments within species were larger than those among species, indicating that the variation of rdnas was useful in phylogenetic studies of spider mite specie ... | 1994 | 7915173 |
| molecular identification of a wolbachia endosymbiont in a tetranychus urticae strain (acari: tetranychidae). | wolbachia, a maternally inherited bacterium, is involved in alterations of arthropod sexuality. reproductive incompatibilities are often observed in miles, but the existence of this microorganism in their cytoplasm has not yet been demonstrated. we identified the presence of wolbachia in a strain of the spider mite tetranychus urticae based on the amplification and sequencing of part of the 16s rdna and ftsz genes. in order to establish the phylogenetic relationships between wolbachia found in t ... | 1996 | 8799741 |
| wolbachia: intracellular manipulators of mite reproduction. | cytoplasmically transmitted wolbachia (alpha-proteobacteria) are a group of closely related intracellular microorganisms that alter reproduction in arthropods. they are found in a few isopods and are widespread in insects. wolbachia are implicated as the cause of parthenogenesis in parasitic wasps, feminization in isopods and reproductive (cytoplasmic) incompatibility in many insects. here we report on the widespread occurrence of wolbachia in spider mites and predatory mites based on a pcr assa ... | 1996 | 8856963 |
| assessing the stability of cystatin/cysteine proteinase complexes using mildly-denaturing gelatin-polyacrylamide gel electrophoresis. | a method for assessing the stability of cystatin/cysteine proteinase complexes using mildly-denaturing gelatin-polyacrylamide gel electrophoresis (gelatin-page) is described. as suggested by the use of well-known cystatins (human stefins a and b, and oryzacystatins i and ii) and the plant cysteine proteinase papain, the ability of cystatin/cysteine proteinase complexes to remain stable during electrophoresis is associated with the degree of affinity between the enzyme and the inhibitor (and inve ... | 1996 | 8907521 |
| 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 ... | 1996 | 8954812 |
| occupational allergy due to spider mites: tetranychus urticae (koch) and panonychus citri (koch). | allergy to both house dust and storage mites is well established, but information about other species of mites is scant. | 1996 | 8955575 |
| [a comparative study of the cholinesterase and carboxylesterase sensitivities of mammals and arthropods to new phenyl and glycidyl esters of dialkyl thiophosphoric acid]. | the antienzymic activities of 14 organophosphorous compounds, the derivatives of dialkyl thiophosphoric acid, towards the acetylcholinesterase (ache), butyrylcholinesterase (buche) and carboxylesterase (ce) from the spring grain aphid and mammals were investigated. the dependence of inhibitory activity of the compounds on their alkyl radical length was shown to be different for the ache from the aphid and man. some less pronounced differences in this dependence were revealed between the buches f ... | 1996 | 9054171 |
| insecticidal, acaricidal and synergistic effects of soosan, pancratium maritimum extracts and constituents. | in assessing the pesticidal activity of soosan, p. maritimum, the bulbs and leaves were extracted using acetone/ethanol & ethanol as solvents and mosquito larvae c. pipiens, as a test organism. the actone/ethanol extract of bulbs was more toxic (lc50: 25 ppm) than that of the leaves (lc50: 75 ppm). crude alkaloids, lycorine, terpenes & sterols and fixed oil were isolated from soosan bulb. their percentages were: 0.193, 0.02, 0.13 and 3.3%, respectively. the acetone/ethanol extract showed a stron ... | 1998 | 9617056 |
| microsatellite sequences are under-represented in two mite genomes. | microsatellites are known to be a common feature of eukaryote genomes. here we investigate the presence of microsatellite sequences in the genome of two mite species, tetranychus urticae and amblyseius fallacis, based on screening of both mite genomic libraries and southern blots of these mites that we compare to two vertebrates. no signal with gt15 or a faint smear with ct10 were obtained in southern analysis for the two mites, whereas both probes strongly bound with vertebrate dna. genomic lib ... | 1998 | 9662474 |
| species-wide homogeneity of nuclear ribosomal its2 sequences in the spider mite tetranychus urticae contrasts with extensive mitochondrial coi polymorphism. | we compared patterns of intraspecific polymorphism of two markers with contrasted modes of evolution, nuclear ribosomal dna (rdna) and mitochondrial dna (mtdna), in the phytophagous mite tetranychus urticae koch. the second internal transcribed spacer (its2) of rdna and a fragment in the mtdna gene coding for cytochrome oxidase i (coi), were pcr-amplified and sequenced in samples of various geographical origins distributed worldwide. the 15 coi haplotypes found fell into two major phylogenetic l ... | 1998 | 9675873 |
| 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 ... | 1999 | 10466216 |
| spider mite allergy in apple-cultivating farmers: european red mite (panonychus ulmi) and two-spotted spider mite (tetranychus urticae) may be important allergens in the development of work-related asthma and rhinitis symptoms. | recent investigations have suggested that the citrus red mite (panonychus citri) is the most important allergen affecting citrus-cultivating farmers with asthma, allergic rhinitis, or both. | 1999 | 10589014 |
| a comparative survey of the hydrolytic enzymes of ectoparasitic and free-living mites. | extracts of ectoparasitic mites of birds (dermanyssus gallinae), sheep (psoroptes ovis) and plants (tetranychus urticae) and of free-living mites (acarus siro) contained acid and alkaline phosphatase, c4 and c8 esterases, lipase, leucine and valine aminopeptidases and a range of glycosidase activities. dermanyssus gallinae and p. ovis, species highly adapted to an animal parasitic lifestyle, had very similar profiles and contained low activities of glycosidases. in contrast, the polyphagous spec ... | 2000 | 10675740 |
| assessment of amblyseius fallacis (acari: phytoseiidae) for biological control of tetranychid mites in an ontario peach orchard. | we introduced a mass-reared pyrethroid-resistant strain of the predatory phytoseiid mite amblyseius fallacis (garman) into an ontario peach orchard in an attempt to control populations of the phytophagous mites panonychus ulmi koch and tetranychus urticae koch (acari: tetranychidae). releases of 1,000 and 2,000 mites per tree were made, at three different times. the release of 2,000 mites per tree in june and in july resulted in significantly higher phytoseiid densities than was observed on cont ... | 1999 | 10737734 |
| some effects of pre-release host-plant on the biological control of panonychus ulmi by the predatory mite amblyseius fallacis. | amblyseius fallacis garman has been selected for pyrethroid resistance and mass reared for experimental release as a biological control agent for tetranychid mites on a number of crops in canada. several releases of this predator onto apple and peach trees have failed to result in the establishment of a. fallacis, or in the biological control of panonychus ulmi koch. here, we test the hypothesis that the change of host-plant at the time of release is a critical factor in the establishment of a. ... | 2000 | 10823354 |
| 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. | 2000 | 10823357 |
| involvement of jasmonate- and salicylate-related signaling pathways for the production of specific herbivore-induced volatiles in plants. | we compared volatiles from lima bean leaves (phaseolus lunatus) infested by either beet armyworm (spodoptera exigua), common armyworm [mythimna (pseudaletia) separata], or two-spotted spider mite (tetranychus urticae). we also analyzed volatiles from the leaves treated with jasmonic acid (ja) and/or methyl salicylate (mesa). the volatiles induced by aqueous ja treatment were qualitatively and quantitatively similar to those induced by s. exigua or m. separata damage. furthermore, both s. exigua ... | 2000 | 10845451 |
| herbivory-induced volatiles elicit defence genes in lima bean leaves. | in 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 ... | 2000 | 10952311 |
| long pcr improves wolbachia dna amplification: wsp sequences found in 76% of sixty-three arthropod species. | bacteria belonging to the genus wolbachia are associated with a variety of reproductive anomalies in arthropods. allele-specific polymerase chain reaction (= standard pcr) routinely has been used to amplify wolbachia dna from arthropods. while testing the two-spotted spider mite tetranychus urticae and other arthropods known to be infected with wolbachia, standard pcr frequently produced false negatives, perhaps because the dna from the arthropod host interfered with amplification by taq dna pol ... | 2000 | 10971717 |
| wolbachia-induced 'hybrid breakdown' in the two-spotted spider mite tetranychus urticae koch. | the most common post-zygotic isolation mechanism between populations of the phytophagous mite tetranychus urticae is 'hybrid breakdown', i.e. when individuals from two different populations are crossed, f1 hybrid females are produced, but f2 recombinant male offspring suffer increased mortality. two-spotted spider mites collected from two populations, one on rose and the other on cucumber plants, were infected with wolbachia bacteria. these bacteria may induce cytoplasmic incompatibility in thei ... | 2000 | 11075704 |
| functional response of euseius finlandicus and amblyseius andersoni to panonychus ulmi on apple and peach leaves in the laboratory. | the functional response of adult females of the predatory mites euseius (amblyseius) finlandicus and amblyseius andersoni to larvae and adult females of the fruit tree red spider mite panonychus ulmi was determined on apple and peach leaf disks in the laboratory at 25 degrees c and 16:8 (l:d). for adult females of p. ulmi the predation efficiency of e. finlandicus was higher on peach than on apple, whereas that of a. andersoni was higher on apple than on peach. efficiency of predation on larvae ... | 2000 | 11110236 |
| the effect of non-pathogenic phylloplane fungi on life-history traits of urticae (acari: tetranychidae). | the direct effect of three common non-pathogenic phylloplane fungi on the life-history traits of tetranychus urticae koch was investigated on intact leaves of the garden bean phaseolus vulgaris l. (var. tendergreen improved), under conditions of low and high water-deficit stress. the survival rate of t. urticae was always reduced by an increase in water-deficit stress, whereas the effect of the fungi depended in part on the watering regime. on two of the three fungi tested, alternaria alternata ... | 2000 | 11110237 |
| 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 ... | 2000 | 11156163 |
| 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 ... | 2000 | 11156167 |
| 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 ... | 2001 | 11228589 |
| 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 ... | 2001 | 11233107 |
| 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%). ... | 2001 | 11273691 |
| modified atmosphere treatments as a potential disinfestation technique for arthropod pests in greenhouses. | incidental transport of arthropods on plant material can be a significant mode of pest entry into greenhouses. we evaluated the use of controlled atmosphere treatments as a potential way to eliminate arthropod pests on plant propagules (i.e., cuttings or small rooted plants). lethal exposures to co2 or n2 were determined for common greenhouse pests including fungus gnat larvae, bradysia sp.; green peach aphid, myzus persicae (sulzer); sweetpotato whitefly, bemisia sp.; twospotted spider mite, te ... | 2001 | 11332835 |
| 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 ... | 2000 | 11354616 |
| acaricide toxicity and resistance in larvae of different strains of tetranychus urticae and panonychus ulmi (acari: tetranychidae). | the toxicities of eight structurally different acaricidal compounds to six-legged larvae (first motile stage) of three laboratory strains of the two-spotted spider mite, tetranychus uritcae, and the european red mite, panonychus ulmi, were evaluated following spray application. the larvae of five field-derived strains of t urticae originating from france, italy, brazil, california and florida were also tested for their susceptibilities to discriminating concentrations of several acaricides resul ... | 2001 | 11455655 |
| 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 ... | 2001 | 11484053 |
| 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 ... | 2001 | 11508528 |
| species association among predaceous and phytophagous apple mites (acari: eriophyidae, phytoseiidae, stigmaeidae, tetranychidae). | predator-predator, predator-prey, and prey-prey associations among nine species of mites were studied in a plot of 100 'red delicious' apple (malus pumila miller) trees from 1990 to 1997. in 1990, seven-year-old trees were inoculated with panonychus ulmi (koch), tetranychus urticae koch (acari: tetranychidae) or both, and sprayed with azinphosmethyl (alone or plus endosulfan), or nothing. the species zetzellia mali (ewing) (acari: stigmaeidae), amblyseius andersoni chant (acari: phytoseiidae), e ... | 2001 | 11513362 |
| ige binding components in tetranychus urticae and panonychus ulmi-derived crude extracts and their cross-reactivity with domestic mites. | recent investigation has revealed that spider mites such as tetranychus urticae and panonychus ulmi are important allergens in the development of occupational asthma among apple farmers. | 2001 | 11591197 |
| sublethal effects of esfenvalerate residues on pyrethroid resistant typhlodromus pyri (acari: phytoseiidae) and its prey panonychus ulmi and tetranychus urticae (acari: tetranychidae). | the effect of residues of esfenvalerate on oviposition of the resistant strain of the predatory mite typhlodromus pyri and its main prey, european red mite panonychus ulmi and two-spotted spider mite tetranychus urticae, were investigated. t. pyri showed a significant linear reduction in oviposition after 24 h in the presence of increasing levels of esfenvalerate residue applied at the field rate. furthermore, when given a choice, t. pyri preferred to lay eggs on residue-free surfaces. of the tw ... | 2001 | 11603738 |
| mechanisms of resistance to organophosphates in tetranychus urticae (acari: tetranychidae) from greece. | we investigated the mechanisms conferring resistance to methyl-parathion (44-fold) and to methomyl (8-fold) in tetranychus urticae from greece by studying the effect of synergists on the resistance and the kinetic characteristics of various enzymes in a resistant strain (rlab) and a susceptible reference strain (samb). it is shown that s,s,s-tributyl phosphorotrithioate, a synergist that inhibits esterases and glutathione s-transferases, and piperonyl butoxide, a synergist that inhibits cytochro ... | 2002 | 11886776 |
| fluorometric microplate assay to measure glutathione s-transferase activity in insects and mites using monochlorobimane. | elevated levels of glutathione s-transferases (gsts) play a major role as a mechanism of resistance to insecticides and acaricides in resistant pest insects and mites, respectively. such compounds are either detoxicated directly via phase i metabolism or detoxicated by phase ii metabolism of metabolites as formed by microsomal monooxygenases. here we used monochlorobimane (mcb) as an artificial substrate and glutathione to determine total gst activity in equivalents of single pest insects and sp ... | 2002 | 11950219 |
| insecticidal 2-hydroxy-3-alkyl-1,4-naphthoquinones: correlation of inhibition of ubiquinol cytochrome c oxidoreductase (complex iii) with insecticidal activity. | the insecticidal and in vitro activities of four homologous series of 2-hydroxy and acetoxy-3-substituted-1,4-naphthoquinones have been measured and correlated with their (log) octanol/water partition coefficients (log ko/w). in vitro activity against mitochondrial complex iii was only exhibited by 2-hydroxy-3-alkyl-1,4-naphthoquinones, indicating that the 2-acetoxy compounds act as proinsecticides. good correlation was observed between in vivo activity against the two-spotted spider mite, tetra ... | 2002 | 11975169 |
| biological control of spider mites on grape by phytoseiid mites (acari: tetranychidae, phytoseiidae): emphasis on regional aspects. | leaf samples were taken from 34 (1998) and 10 (1999) vineyards in five valleys in western oregon to assess spider mite pests and biological control by predaceous phytoseiid mites. a leaf at a coordinate of every 10 m of border, 5 m into a vineyard, was taken to minimize edge effects; 20 leaves were taken at regular intervals from vineyard centers. variables recorded at each site included grape variety and plant age, chemicals used, and vegetation next to vineyards. sites were rated as occurring ... | 2002 | 12020011 |
| identification of immunoglobulin e binding components of the two-spotted spider mite tetranychus urticae: allergenic relationships with the citrus red mite and house-dust mite. | the two-spotted mite (tsm) is commonly found on fruit trees, herbaceous plants, and greenhouse flowers. however, a recent investigation indicated that the sensitization rate to tsm was as high as that of house-dust mites (hdms) in nonfarmers as well as in farmers working in orchards in this country. the aim of this study was to identify immunoglobulin e (ige)-binding components within tsm and to evaluate the allergenic relationship with the citrus red mite (crm) and hdm. sera were collected from ... | 2002 | 12125508 |
| within- and between-population variation for wolbachia-induced reproductive incompatibility in a haplodiploid mite. | wolbachia pipientis is a bacterium that induces cytoplasmic incompatibility (ci), the phenomenon in which infected males are reproductively incompatible with uninfected females. ci spreads in a population of hosts because it reduces the fitness of uninfected females relative to infected females. ci encompasses two steps: modification (mod) of sperm of infected males and rescuing (resc) of these chromosomes by wolbachia in the egg. infections associated with ci have mod+ resa+ phenotypes. however ... | 2002 | 12206235 |
| 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 ... | 2001 | 12206584 |
| expression of pair-rule gene homologues in a chelicerate: early patterning of the two-spotted spider mite tetranychus urticae. | embryo segmentation has been studied extensively in the fruit fly, drosophila. these studies have demonstrated that a mechanism acting with dual segment periodicity is required for correct patterning of the body plan in this insect, but the evolutionary origin of the mechanism, the pair-rule system, is unclear. we have examined the expression of the homologues of two drosophila pair-rule genes, runt and paired (pax group iii), in segmenting embryos of the two-spotted spider mite (tetranychus urt ... | 2002 | 12403716 |
| beauveria bassiana yeast phase on agar medium and its pathogenicity against diatraea saccharalis (lepidoptera: crambidae) and tetranychus urticae (acari: tetranychidae). | beauveria bassiana colonizes insect hosts initially through a yeast phase, which is common in some artificial liquid cultures, but not reported on artificial solid media. we describe a yeast-like phase for b. bassiana isolate 447 (atcc 20872) on macconkey agar and its virulence toward diatraea saccharalis and tetranychus urticae. the yeast-like cells of b. bassiana developed by budding from germinating conidia after 24-h incubation. cells were typically 5-10 microm and fungal colonies were initi ... | 2002 | 12445790 |
| 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 ... | 2001 | 12455871 |
| effect of tomato leaf hairiness on functional and numerical response of neoseiulus californicus (acari: phytoseiidae). | the objective of this study was to determine whether differences in hairiness of tomato plants affect the functional and numerical response of the predator neoseiulus californicus mcgregor attacking the two-spotted spider mite, tetranychus urticae koch. two tomato hybrids with different density of glandular hairs were used. the functional response was measured by offering eggs and adults of t urticae at densities ranging from 4 to 64 items per tomato leaflet (surface ca. 6.3 cm2); eggs were offe ... | 2001 | 12455873 |
| short-term changes in consumption and oviposition rates of neoseiulus californicus strains (acari: phytoseiidae) after a diet shift. | short-term effects on consumption and oviposition rates of four strains of neoseiulus californicus (mcgregor) after a diet shift were evaluated. the new feeding conditions experienced by the predators were six fixed densities of eggs or protonymphs of tetranychus urticae koch placed on excised strawberry leaflet discs and maintained under laboratory conditions (25 +/- 1 degrees c, 75-85% rh, 16l: 8d). the observations were made on the first and the fifth day of the experiment. the phytoseiids ca ... | 2001 | 12465851 |
| 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 ... | 2002 | 12542009 |
| genetic conflicts over sex ratio: mite-endosymbiont interactions. | nucleocytoplasmic genetic conflicts arise as a result of asymmetric transmission of cytoplasmic and nuclear genes. spread of a cytoplasmic element promoting female-biased sex ratios creates selection on nuclear genes for mechanisms that decrease the bias. here we investigate the conflict over sex ratio between the cytoplasmic bacterium wolbachia and the two-spotted spider mite tetranychus urticae koch. we show that, first, infected females produce significantly more female-biased sex ratios than ... | 2003 | 12675371 |
| 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. | 2003 | 12708983 |
| effects of temperature on the establishment potential of the predatory mite amblyseius californicus mcgregor (acari: phytoseiidae) in the uk. | amblyseius californicus was introduced into the uk in the early 1990s as a biocontrol agent against glasshouse red spider mite tetranychus urticae. this study investigated the effects of temperature on the establishment potential of a. californicus in the uk in the light of recent reports of their successful overwintering outside of glasshouse environments. the developmental thresholds were 9.9 and 8.6 degrees c respectively using simple and weighted linear regression. using the day-degree requi ... | 2002 | 12770070 |
| structure-function relationships affecting the insecticidal and miticidal activity of sugar esters. | synthetic sugar esters are a relatively new class of insecticidal compounds that are produced by reacting sugars with fatty acids. the objective of this research was to determine how systematic alterations in sugar or fatty acid components of sugar ester compounds influenced their insecticidal properties. sucrose octanoate, sorbitol octanoate, sorbitol decanoate, sorbitol caproate, xylitol octanoate, xylitol decanoate and xylitol dodecanoate were synthesized and evaluated against a range of arth ... | 2003 | 12852599 |
| 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 ... | 2003 | 12908920 |
| no variation for wolbachia-induced hybrid breakdown in two populations of a spider mite. | wolbachia are cytoplasmically transmitted bacteria that infect several species of mites. in the two-spotted spider mite tetranychus urticae koch this symbiont can induce reproductive incompatibility. wolbachia-induced reproductive incompatibility is observed in crosses between wolbachia-infected (w) males and uninfected (u) females. this incompatibility is expressed in f1 broods as male-biased sex ratios, an effect called cytoplasmic incompatibility (ci). however, in the two-spotted spider mite, ... | 2003 | 14580056 |
| 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 ... | 2003 | 14580059 |
| sorting out the effects of wolbachia, genotype and inbreeding on life-history traits of a spider mite. | wolbachia bacteria manipulate host reproduction by inducing cytoplasmic incompatibility (ci) and sex ratio distortion. wolbachia are transmitted from mother to offspring through the cytoplasm of the egg. therefore, reproduction of wolbachia is tightly coupled to reproduction of its host. mathematical analysis predicts that in the course of evolution, traits that reduce the physiological costs of the infection will be selectively favored. for a wolbachia-host system to evolve, traits under select ... | 2003 | 14635812 |
| 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 ... | 2003 | 14756399 |
| 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 ... | 2003 | 14969353 |
| development of genetic differentiation and postzygotic isolation in experimental metapopulations of spider mites. | we studied the development of genetic differentiation and postzygotic isolation in experimental metapopulations of the two-spotted spider mite, tetranychus urticae koch. a genetically diverse starter population was made by allowing six inbred sublines to interbreed. then three migration patterns were tested: no migration, or one or three immigrants per subpopulation per generation. variations in four traits were investigated: allozymes, acaricide resistance, diapause, and hatchability. in the al ... | 2003 | 14974684 |
| occupational asthma in greenhouse workers. | a prevalence of asthma over 5% has been reported in flower farmers,and work inside greenhouses has emerged as an additional risk factor. workplace determinants behind this high prevalence has been examined, and a prevalence of sensitization to workplace allergens over 30% has been reported being pollens, moulds, and tetranychus urticae allergens the main sensitizers. bronchial challenge tests in the workplace have demonstrated occupational asthma in more than 20% of the sensitized greenhouse gro ... | 2004 | 15021185 |
| qualitative and quantitative variation among volatile profiles induced by tetranychus urticae feeding on plants from various families. | many plant species are known to emit herbivore-induced volatiles in response to herbivory. the spider mite tetranychus urticae koch is a generalist that can feed on several hundreds of host plant species. volatiles emitted by t. urticae-infested plants of 11 species were compared: soybean (glycine max), golden chain (laburnum anagyroides), black locust (robinia pseudo-acacia), cowpea (vigna unguiculata), tobacco (nicotiana tabacum), eggplant (solanum melalonga), thorn apple (datura stramonium), ... | 2004 | 15074658 |
| 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 ... | 2004 | 15112723 |
| 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 ... | 2004 | 15122016 |
| effect of temperature on life history of the predatory mite amblyseius (neoseiulus) californicus (acari: phytoseiidae). | amblyseius (neoseiulus) californicus is an indigenous mite in japan that feeds on many spider mite species. we evaluated the development, survivorship and life-history parameters of a. californicus on a diet of eggs of tetranychus urticae (red form). more than 97.3% of a. californicus eggs hatched and more than 81.6% of newly hatched larvae attained maturity at temperatures between 15 and 35 degrees c. females oviposited at 37.5 degrees c, but no eggs hatched. at 40 degrees c, no females laid eg ... | 2004 | 15139269 |
| role of mites and thrips in the agrobiocoenosis of the soybean. | soy beans dangerous pests are mites and thrips, that is why the present paper aims at the examination of the changes in their numbers and dominance relations of some varieties of different maturity groups. the small plot experiments were conducted in kisalföld region with the following soybean varieties: early ripening bólyi 38, evans, mccall, middle ripening bólyi 45 and late ripening eszter, zsuzsanna and borza, in mosonmagyaróvár. mites and thrips were collected every week with berlese-extrac ... | 2003 | 15149112 |
| 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 ... | 2003 | 15149115 |
| 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 ... | 2004 | 15154481 |
| comparing greenhouse sprayers: the dose-transfer process. | three sprayers were evaluated for their affect on retention and efficacy: a carbon dioxide powered high-volume sprayer, a dramm coldfogger, and an electrostatic spraying systems (ess) sprayer with air-assistance. the active ingredients used were spinosad and azadirachtin. the plant canopy was constructed in the greenhouse using potted soybeans (glycine max (l) merrill cr pioneer 9392). application efficacy with spinosad was assessed using thrips [western flower thrips, frankliniella occidentalis ... | 2004 | 15154520 |
| 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 ... | 2004 | 15176731 |
| effects of fungicide residues on the survival, fecundity, and predation of the mites tetranychus urticae (acari: tetranychidae) and galendromus occidentalis (acari: phytoseiidae). | representative fungicides from three or four families used for management of powdery mildew and other diseases in tree fruits were evaluated for their effects on a common spider mite and predator mite species, respectively. a modified munger cell technique was effective in measuring the response of phytophagous and predaceous mites to fungicide residues on detached leaves in the laboratory. demethylation-inhibiting (dmi) (imidazole [triflumazole] and triazole [myclobutanil]) and strobilurin (tri ... | 2004 | 15279277 |
| effects of nacl-stressed citrus plants on life-history parameters of tetranychus urticae (acari: tetranychidae). | tetranychus urticae is an important pest of citrus, especially lemon and mandarin, under mediterranean climate. factors leading to this problem are poorly understood, but saline stress is suspected to contribute to spider mite outbreaks. in this study, the effect of nacl concentration in nutritive solutions used to water potted young mandarin trees on population growth of t. urticae reared on leaf discs obtained from these plants was investigated. although the differences observed between treate ... | 2004 | 15285138 |
| [diversity of phytophagous and pathogens and their damage to mints (mentha)]. | the aim of this work was to estimate the phytopathologic condition of mints grown and self-growing in kaunas botanical garden of vytautas magnus university and elsewhere in lithuania; and to identify the specific constitution, the spread and damage of the main pests and disease agents. material and methods: observations and examination were carried out with two local, four introduced mint species and with four hybrids in 1997-2003. we estimated the plant condition by identifying the intensity of ... | 2004 | 15299999 |
| herbivore-induced defense response in a model legume. two-spotted spider mites induce emission of (e)-beta-ocimene and transcript accumulation of (e)-beta-ocimene synthase in lotus japonicus. | indirect defense of plants against herbivores often involves the induced emission of volatile infochemicals including terpenoids that attract natural enemies of the herbivores. we report the isolation and characterization of a terpene synthase cdna (ljebetaos) from a model legume, lotus japonicus. recombinant ljebetaos enzyme produced (e)-beta-ocimene (98%) and its z-isomer (2%). transcripts of ljebetaos were induced in l. japonicus plants infested with two-spotted spider mites (tetranychus urti ... | 2004 | 15310830 |
| 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 ... | 2004 | 15310835 |
| acaricidal properties of a chenopodium-based botanical. | the emulsifiable concentrate uda-245 [25% ec (vol:vol)], based on an essential oil extract from chenopodium ambrosioides variety ambrosioides, a north american herbaceous plant, was compared with commercially available pesticides for their effectiveness to control the adult stage and egg hatch of the twospotted spider mite, tetranychus urticae koch (acari: tetranychidae) and the european red mite, panonychus ulmi (koch) (acari: tetranychidae). after a laboratory bioassay with adult twospotted sp ... | 2004 | 15384350 |
| 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 ... | 2004 | 15503521 |
| evaluation of prey-stage preference as an indicator of life-style type in phytoseiid mites. | discriminant analysis (da) models were developed and applied to examine the use of prey-stage preference (tetranychus urticae koch egg versus larval prey) in the classification of phytoseiid mites into life-style types. prey-stage preferences and developmental times when preying on t. urticae, and relative ovipositional rates on six food categories were determined for four phytoseiid species occurring on apple in central and eastern oregon, usa: galendromus flumenis (chant), galendromus occident ... | 2004 | 15560524 |
| phytoseiid mites on unsprayed apple trees in oregon, and other western states (usa): distributions, life-style types and relevance to commercial orchards. | in unsprayed apple trees in eastern oregon, galendromus flumenis (chant), galendromus occidentalis (nesbitt), typhlodromus caudiglans schuster and metaseiulus citri (garman and mcgregor) were common phytoseiid mites; common plant-feeding mites were the eriophyid, aculus schlechtendali nalepa, the brown mite, bryobia rubrioculus (scheuten) and eotetranychus spp.; apple rust mites seemed to be the primary prey for phytoseiids; the spider mites, tetranychus urticae koch and panonychus ulmi (koch) w ... | 2004 | 15560525 |
| predation risk affects diapause induction in the spider mite tetranychus urticae. | whenever diapause induction triggers movement into another microhabitat or the development of protective morphological structures, this may also alter predation risk. if the risk of being eaten is lower in the diapause phase, then there may be selection favouring diapause induction in response to predators or their cues. in this article, we studied the effect of the predatory mite typhlodromus pyri on diapause induction in the spider mite tetranychus urticae. we used a greek strain because under ... | 2004 | 15651527 |
| 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 ... | 2004 | 15672666 |
| 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. | 2005 | 15727587 |
| 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 ... | 2004 | 15759407 |
| effects of soil moisture and temperature on reproduction and development of twospotted spider mite (acari: tetranychidae) in strawberries. | the effects of soil moisture and temperature on the reproduction of twospotted spider mite, tetranychus urticae koch (acari: tetranychidae), were examined in laboratory and field tests in strawberries, fragaria x ananassa duchesne, in florida. different soil moisture levels (low, moderate, and high) were compared to determine how soil moisture affects the reproduction and development of twospotted spider mite. in addition to soil moisture, different irrigation techniques (drip versus drip/overhe ... | 2005 | 15765677 |
| diapause incidence in the two-spotted spider mite increases due to predator presence, not due to selective predation. | we recently reported evidence for increased diapause incidence in the spider mite tetranychus urticae in presence of the predatory mite typhlodromus pyri. this effect may arise from (1) selective predation on non-diapause spider mites, (2) predator-induced diapause in spider mites, or (3) both. using a different strain of t. urticae, we first recovered increased diapause incidence in association with predators. then, we tested for selective feeding in two-choice experiments with equal numbers of ... | 2005 | 15777002 |
| effects of dispersal, predators (acari: phytoseiidae), weather, and ground cover treatments on populations of tetranychus urticae (acari: tetranychidae) in apple orchards. | in a 2-yr study of causes of mite outbreaks in apple (malus spp.) orchards in nova scotia, we monitored immigration of tetranychus urticae koch from orchard ground cover into trees populated by the generalist phytoseiid predator typhlodromus pyri scheuten. in both years, t. urticae-days in the tree canopy increased with number of t. urticae caught in sticky bands on tree trunks. in 2000, t. urticae-days were negatively correlated with t. pyri-days. lack of correlation in 2001 was attributed to h ... | 2005 | 16022315 |
| within-plant distribution of twospotted spider mites (acari: tetranychidae) on impatiens: development of a presence-absence sampling plan. | the twospotted spider mite, tetranychus urticae koch, is an important pest of impatiens, a floricultural crop of increasing economic importance in the united states. the large amount of foliage on individual impatiens plants, the small size of mites, and their ability to quickly build high populations make a reliable sampling method essential when developing a pest management program. in our study, we were particularly interested in using spider mite counts as a basis for releasing biological co ... | 2005 | 16022337 |
| significance of habitat type for the genetic population structure of panonychus citri (acari: tetranychidae). | restricted migration and habitat fragmentation promote genetic differentiation between populations. because most of the hosts of panonychus citri are woody plants, mainly citrus trees that are usually planted at intervals of several metres, this mite likely faces more risks (e.g., starvation) by dispersing between host plants, compared to other spider mite species that infest both herbaceous and woody plants, such as tetranychus urticae. such a limited gene flow between patches (host plants) can ... | 2005 | 16082921 |
| the involvement of volatile infochemicals from spider mites and from food-plants in prey location of the generalist predatory mite neoseiulus californicus. | we investigated volatile infochemicals possibly involved in location of the generalist predatory mite neoseiulus californicus to plants infested with spider mites in a y-tube olfactometer. the predators significantly preferred volatiles from lima bean leaves infested with tetranychus urticae to uninfested lima bean leaves. likewise, they were attracted to volatiles from artificially damaged lima bean leaves and those from t. urticae plus their visible products. significantly more predators chose ... | 2005 | 16132210 |
| 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 ... | 2005 | 16132739 |
| acaricidal and cytotoxic activities of extracts from selected genera of australian lamiaceae. | crude foliar extracts of 67 species from six subfamilies of australian lamiaceae were screened by whole organism contact toxicity on the polyphagous mite tetranychus urticae koch (acari: tetranychidae) by using a potter precision spray tower. cytotoxicity assessments against insect cell lines from spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae) and drosophila melanogaster (meigen) (diptera: drosophilidae) also were made. the spodoptera cell line was more susceptible to extracts than ... | 2005 | 16156579 |