Search results for "Tetranychus"

Effects of Rosmarinus officinalis and Salvia officinalis essential oils on Tetranychus urticae Koch (Acari: Tetranychidae)

2013

Laboratory trials were carried out to characterize Rosmarinus officinal and Salvia officinalis essential oils and to evaluate their pesticidal activities against Tetranychus urticae. Slide-dip and leaf-disk bioassays were employed to study the mortality caused by these plant oils on two-spotted spiders. Different dilutions of both essential oils (0.10-0.25%, v/v) caused acute contact toxicity, although the sage extract showed greater acaricidal activity than rosemary oil. Mortality rates of 95-100% were observed at all the sage oil dosages and when rosemary emulsions contained at least 0.20% of essential oil. In the residual contact experiments (leaf-disk assays), 0.15-0.25% of sage oil or …

Wound-induced responses in leaves of strawberry cultivars differing in susceptibility to spider mite

2002

Summary The effect of leaf detachment and wounding on the activities of oxidative enzymes and ethylene production was studied in strawberry (Fragaria × ananassa) cultivars, differing in susceptibility to the spider mite (Tetranychus urticae Koch.). Strawberry plants were cultivated during winter in two growth conditions - with and without overwintering, in greenhouse and laboratory, respectively. Polyphenol oxidase activity, peroxidase activity and catalase activity in strawberry leaves depended on the cultivar analysed, type of treatment (detachment or detachment and wounding), as well as on plant growth conditions. Activities of all analysed enzymes were higher in control plants grown in …

Contrasting effects ofWolbachiaon cytoplasmic incompatibility and fecundity in the haplodiploid miteTetranychus urticae

2002

Recent studies on Wolbachia-induced incompatibility in haplodiploid insects and mites have revealed a diversity of cytoplasmic incompatibility (CI) patterns among host species. Here, we report intraspecific diversity in CI expression among four strains of the arrhenotokous mite Tetranychus urticae and in T. turkestani. Variability of CI expression within T. urticae ranged from no CI to complete CI, and included either female embryonic mortality or male conversion types of CI. A fecundity cost attributed to the infection with the high-CI Wolbachia strain was the highest ever recorded for Wolbachia (−80 to −100% decrease). Sequence polymorphism at a 550-bp-portion of Wolbachia wsp gene reveal…

On the perception of leaf morphology and visible light by Tetranychus urticae Koch (Acariformes, Tetranychidae)

2022

The two-spotted spider mite Tetranychus urticae is one of the most polyphagous and most damaging pests worldwide. The behaviour of the mite differs on its various host plants and this could influence crop defence strategies. We investigated the perception of leaf morphology by T. urticae in relation to the effects of visible light on the selection of sites on which females prefer to live and feed. Mite females chose the shaded surface when smooth and glabrous lemon leaves were offered as a surface for living and feeding, showing a photophobic behaviour. However, they clearly preferred the abaxial surface of bean leaves regardless of the presence or absence of visible light. As no difference…

Laboratory evaluation of the effect of plant extracts on Tetranychus urticae Koch (Acariformes, Tetranychidae)

2005

Acetone extracts of Annona cherimola Mill., Melia azedarach L., Artemisia absinthium L. and Quassia spp., were tested in laboratory trials on young females of Tetranychus urticae Koch (Acariformes,Tetranychidae). In the post-infestation tests, extracts of Melia and Annona caused a high mortality of the target females (84% and 96% for Melia and Annona, respectively) after 24 hours and 100% for both extracts after 48 hours. On the other hand Artemisia extracts caused 84% mortality of females after 10 days even if the oviposition rate was statistically lower than in the controls (2.5 and 6.7 eggs/female/day for Artemisia and controls, respectively).

Host plant range of Tetranychus evansi (Acari: tetranychidae) in the Mediterranean: Field and laboratory evidences.

2008

Tracking mite trophic interactions by multiplex PCR

2020

Background A thorough knowledge of trophic webs in agroecosystems is essential to achieve successful biological pest control. Phytoseiid mites are the most efficient natural enemies of tetranychid mites, which include several important pests worldwide. Nevertheless, phytoseiids may feed on other food sources including other microarthropods, plants and even other phytoseiids (intraguild predation), which can interfere with biological control services. Molecular gut content analysis is a valuable tool for characterizing trophic interactions, mainly when working on microarthropods such as mites. We have designed new primers for Phytoseiidae, Tetranychidae and Thysanoptera identification and th…