ABSTRACT
Western flower thrips (WFT), Frankliniella occidentalis (Pergande), were first reported in the mid-south in Louisiana in 1984 (Graves et al., 1987) and have since been identified throughout the cotton belt. Its effect on seedling cotton is similar to damage from other thrips. WFT can occur in high densities in blooming cotton when immatures feed principally on leaves causing them to appear dry and scorched, and adults congregate in blooms, causing improper opening. Although it has been reported as a predator on mites, it did not demonstrate predacity relative to Tetranychus urticae Koch in laboratory conditions with low numbers of spider mite eggs, larvae and adults. In comparison with Scolothrips pallidus (Beach), a thrips which is very predaceous on spider mites, differences in behavior and morphology are evident. Behavioral observations indicate a possible avoidance of spider mites by WFT. The method and site of feeding of WFT and T. urticae are similar, suggesting that basic competition for food may be a factor in possible reduction of mite densities in the presence of high densities of WFT.
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