biological reactions of the two-spotted spider mite (tss), tetranychus urticae, were studied on nine cultivars of tomatoes. the spider mites were reared on leaf discs, taken from fruiting stages of the host plants. the effects of feeding on some tomato cultivars, namely: long shelf life, meran (greenhouse cultivars), redclude, western red, imperial, yazd, mazandaran, west azarbaijan and khorasa...

Sex-ratio adjustments are commonly observed in haplodiploid species. However, the underlying proximate mechanisms remain elusive. We investigated these mechanisms in Tetranychus urticae, a haplodiploid spider mite known to adjust sex ratio in response to the level of local mate competition (LMC). In this species, egg size determines fertilization probability, with larger eggs being more likely ...

J. Agric. Entomol. l(}(3):197-203 (July 1993) ABSTRACT Based on data from apple trees without the presence of any predatory mites, the effect of the pyrethroid lambdacyhalothrin on population density of the twospotted spider mite, Tetranychus urticae Koch, is reported. Results show that significantly (P < 0.05) higher numbers of T. urticae were found in pyrethroid·treatcd trees relative to the ...