Control of Thrips and Aphids on Seedling Cotton with Temik and Thimet, 1987

Abstract

Abstract The efficacy of Temik and Thimet was evaluated at 3 rates, 0.5, 0.75 and 1.0 lb (AI)/acre, with and without Terraclor Super-X (TSX) at the Northeast Research Station, St. Joseph, La. Orthene 80S seed treatments, 6.4 oz (AI)/cwt, were used as controls. Test plots were replicated 4 times in a randomized complete block design, and were 4 rows (40- inch spacing) × 65 ft. Cotton was planted on 13 May on a commerce silt loam soil, which was fertilized before planting with 60 lb/acre of nitrogen. Test treatments were applied in furrow with a John Deere 7100 planter equipped with granular applicator split boxes. Major and secondary pest treatments were initiated in June and maintained as needed through August. Treatment efficacy for thrips and cotton aphids was measured by washing insects from 10 seedling cotton plants/plot onto 300-mesh screens, backwashing them onto lined filter paper (7 cm), and counting them with the aid of a binocular dissecting microscope. Collections and observations on these pests were made on 4, 10, and 15 Jun. Data on populations are reported as the mean no./25 plants sampled across dates. Stand and skip data were recorded by counting all plants and skips 18 inches or greater on the center two rows. Yield was estimated by harvesting the two center rows with a mechanical harvester on 10 and 22 Oct.