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Mite Infestation (mite + infestation)
Selected AbstractsParasitism by the mite Trombidium breei on four U.K. butterfly speciesECOLOGICAL ENTOMOLOGY, Issue 6 2002L. Conradt Abstract 1. The incidence of parasitism by larvae of the mite species Trombidium breei was reported in one population of the lycaenid butterfly Polyommatus icarus, four populations of the satyrine butterfly Maniola jurtina, one population of the satyrine butterfly Aphantopus hyperanthus, and two populations of the satyrine butterfly Pyronia tithonus, as well as on one specimen of the dipteran Alophorus hemiptera. A considerable proportion of butterflies (11-50%) was infested in all study populations. 2. The pattern of infestation was examined in detail in M. jurtina. Males had a significantly higher incidence of infestation than females, and middle-aged butterflies had a higher incidence of infestation than old or young butterflies. The incidence of infestation peaked in the middle of the flight season, and this seasonal effect was independent of the effect of butterfly age. 3. Using a model based on capture-recapture data, it was estimated that a hypothetical ideal male M. jurtina that lives exactly the mean expected lifespan of 9-10 days has an approximately 75% chance of becoming infested with mites at least once during its lifetime, a mean time to first infestation of 3-4 days, and an average infestation persistence time of 2-3 days. 4. Capture-recapture data failed to show any effect of mite infestation on the lifespan or within-habitat movement rate of M. jurtina. 5. In experiments in which individual butterflies were taken out of their normal habitat and released, M. jurtina and P. tithonus that were infested with mite larvae did not differ from uninfested individuals in the efficiency with which they returned to suitable habitat. Thus, parasitism by T. breei larvae had no detectable effects on flight performance or orientation ability. 6. The results suggest that trombidiid mite larvae have limited potential in the biological control of insect pests. [source] Disruption of an exotic mutualism can improve management of an invasive plant: varroa mite, honeybees and biological control of Scotch broom Cytisus scoparius in New ZealandJOURNAL OF APPLIED ECOLOGY, Issue 2 2010Quentin Paynter Summary 1.,A seed-feeding biocontrol agent Bruchidius villosus was released in New Zealand (NZ) to control the invasive European shrub, broom Cytisus scoparius, in 1988 but it was subsequently considered unable to destroy sufficient seed to suppress broom populations. We hypothesized that an invasive mite Varroa destructor, which has caused honeybee decline in NZ, may cause pollinator limitation, so that the additional impact of B. villosus might now reach thresholds for population suppression. 2.,We performed manipulative pollination treatments and broad-scale surveys of pollination, seed rain and seed destruction by B. villosus to investigate how pollinator limitation and biocontrol interact throughout the NZ range of broom. 3.,The effect of reduced pollination in combination with seed-destruction was explored using a population model parameterized for NZ populations. 4.,Broom seed rain ranged from 59 to 21 416 seeds m,2 from 2004 to 2008, and was closely correlated with visitation frequency of honeybees and bumblebees. Infestation of broom seeds by B. villosus is expected to eventually reach 73% (the average rate observed at the localities adjacent to early release sites). 5.,The model demonstrated that 73% seed destruction, combined with an absence of honeybee pollination, could cause broom extinction at many sites and, where broom persists, reduce the intensity of treatment required to control broom by conventional means. 6.,Nevertheless, seed rain was predicted to be sufficient to maintain broom invasions over many sites in NZ, even in the presence of the varroa mite and B. villosus, largely due to the continued presence of commercial beehives that are treated for varroa mite infestation. 7.,Synthesis and applications. Reduced pollination through absence of honeybees can reduce broom seed set to levels at which biocontrol can be more effective. To capitalize on the impact of the varroa mite on feral honeybees, improved management of commercial beehives (for example, withdrawal of licences for beekeepers to locate hives on Department of Conservation land) could be used as part of a successful integrated broom management programme at many sites in NZ. [source] Effects of Macrocheles mites on longevity of males of the dimorphic dung beetle Onthophagus binodisJOURNAL OF ZOOLOGY, Issue 4 2001Janne S. Kotiaho Abstract In this study we tested the nature of the phoretic relationship between the cosmopolitan mite Macrocheles merdarius and the dimorphic dung beetle Onthophagus binodis. We observed and experimentally manipulated the number of mites on individual beetles and tested how mite infestation affects male longevity. There was a significant effect of mites on male longevity: males in our mites-added treatment died on average 15 days earlier than males in our mites-removed treatment. Interestingly, the number of mites on males was significantly repeatable suggesting that individuals may differ in their susceptibility to infestation. Major males had more mites on them than minor males, and the proportion of mites on minor males was negatively density dependent. [source] Dust mite infestation of flour samplesALLERGY, Issue 12 2009F. C. Yi Background:, Ingestion of flour contaminated with dust mite may trigger severe anaphylaxis in tropical and sub-tropical regions. Aims:, This study aimed to evaluate environmental factors that affect dust mite propagation in the tropics. Materials & Methods:, Dust mites were introduced to a variety of flour samples and incubated at two different environmental conditions. Results: It was found that dust mites populations flourished best in wheat flour compared to other varieties of flour, and at ambient temperatures with high humidity instead of the air conditioned environment. Conclusion:, Dust mite infestation of flour is dependent on the presence of wheat and high ambient temperature in the tropics. [source] Local and systemic effects of two herbivores with different feeding mechanisms on primary metabolism of cotton leavesPLANT CELL & ENVIRONMENT, Issue 7 2009LILIAN SCHMIDT ABSTRACT Caterpillars and spider mites are herbivores with different feeding mechanisms. Spider mites feed on the cell content via stylets, while caterpillars, as chewing herbivores, remove larger amounts of photosynthetically active tissue. We investigated local and systemic effects of short-term caterpillar and spider mite herbivory on cotton in terms of primary metabolism and growth processes. After short-term caterpillar feeding, leaf growth and water content were decreased in damaged leaves. The glutamate/glutamine ratio increased and other free amino acids were also affected. In contrast, mild spider mite infestation did not affect leaf growth or amino acid composition, but led to an increase in total nitrogen and sucrose concentrations. Both herbivores induced locally increased dark respiration, suggesting an increased mobilization of storage compounds potentially available for synthesis of defensive substances, but did not affect assimilation and transpiration. Systemically induced leaves were not significantly affected by the treatments performed in this study. The results show that cotton plants do not compensate the loss of photosynthetic tissue with higher photosynthetic efficiency of the remaining tissue. However, early plant responses to different herbivores leave their signature in primary metabolism, affecting leaf growth. Changes in amino acid concentrations, total nitrogen and sucrose content may affect subsequent herbivore performance. [source] Scrub-itch mite infestation in the endangered bridled nailtail wallabyAUSTRALIAN VETERINARY JOURNAL, Issue 8 2009JM Old Skin lesions on the ears and inguinal and axillary regions of a number of adult animals within a captive population of the endangered bridled nailtail wallaby (Onychogalea fraenata) were associated with the trombiculid mite, Eutrombicula hirsti. The local inflammatory response of these Australian marsupials is described. [source] | |||||||||||||