THRIPS MANAGEMENT IN COTTON

 The long period of mild weather since the last frost and the hot, dry spring have resulted in a large population of thrips migrating to seedling cotton.  In addition, marginal soil moisture for crop emergence and growth has resulted in low granular insecticide uptake in many areas. For these reasons, foliar insecticides may be justified to reduce thrips damage. Research conducted over several years in north Florida has shown that thrips infestations and oviposition in cotton begin within 1-2 days of the emergence of the crop. By 7-8 days following emergence before the crop has reached the first true leaf stage, high populations of immatures and adults are present. These high populations at a time when the crop typically develops slowly result in considerable damage including crinkled leaves, areas of dead leaf tissue and, in severe cases, dead terminals. Generally, total trips populations at 7-8 days following emergence in excess of 2-3 per plant justify treatment with a foliar insecticide. One of the following insecticides broadcast at the rate of 0.2 lb a.i./ acre will provide excellent control of thrips: acephate (Orthene), dicrotophos (Bidrin), dimethoate (several brands) or methamidophos (Monitor). Cost per acre can be reduced by banding any of the listed insecticides.   (Sprenkel, NFREC News, 2-11)

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