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 ...

the entomopathogenic fungus beauveria bassiana (bals.) vuill. is one of the important arthropod pathogens that can play an important role in the regulation of mite populations in agricultural ecosystems. in this study, the combined effect of a native isolate of fungus b. bassiana (eut105) and ether-extract of plant, ginkgo biloba was evaluated against the two-spotted spider mite, tetranychus ur...

The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were conducted during 2007-2009 in Oregon and Washington hop yards to evaluate the effect of timing ...

The twospotted spider mite, Tetranychus urticae Koch, is among the most economically important pests in strawberries (Fragaria spp.). As T. urticae feeds, it ingests mesophyll cells that contain pigments essential for physiologic function and alters radiant energy use of the leaf tissue, severely compromising plant health and productivity. In our study, diffuse reflectance spectroscopy in the v...

The two-spotted spider mite Tetranychus urticae Koch is one of the economically most important pests in a wide range of outdoor and protected crops worldwide. Its control has been and still is largely based on the use of insecticides and acaricides. However, due to its short life cycle, abundant progeny and arrhenotokous reproduction, it is able to develop resistance to these compounds very rap...

During April-June 2010, red two-spotted carmine spider mites Tetranychus urticae Koch (Trombidiformes: Tetranychidae) were found on aerial apical parts of Ashwagandha Withania somnifera (L.) Dunal (Solanales: Solanaceae) plants in the Amritsar District of Punjab Province in the North Indian plains. The mites fed on the leaves, making them shiny white in color, which gradually dried off and were...

The experiment was conducted to study the effectiveness of four commonly used chemicals viz., deltamethrin, cypermethrin, malathion and sulphur against two-spotted spider mite (TSSM), Tetranychus urticae Koch on potted bean plants and on excised leaf discs. Mite population remained significantly lower in all treated plots except malathion treatment. The population of T. urticae differed signifi...

the two-spotted spider mite, tetranychus urticae koch, is a polyphagus pest which infests wide range of field, garden and greenhouse crops worldwide. pesticide applications against this pest have caused development of resistance, undesirable effects on non target organisms and environment and secondary pest outbreak. in recent years, herbal essential oils have received attention as natural plan...

The two-spotted spider mite, Tetranychus urticae Koch is a major pest that feeds on >1,100 plant species. Many perennial crops including hop (Humulus lupulus) are routinely plagued by T. urticae infestations. Hop is a specialty crop in Pacific Northwest states, where 99% of all U.S. hops are produced. To suppress T. urticae, growers often apply various acaricides. Unfortunately T. urticae has b...

The two-spotted spider mite, Tetranychus urticae, is a chelicerate herbivore with an extremely wide host range and an extraordinary ability to develop pesticide resistance. Due to its responsiveness to natural and synthetic xenobiotics, the spider mite is becoming a prime pest herbivore model for studies of the evolution of host range, plant-herbivore interactions and mechanisms of xenobiotic r...