Management of Cutworms with In-Furrow Insecticide Treatments at Planting, 1991

Abstract

Abstract Cotton was planted no-till on 13 May into a residue of hairy vetch, Vicia villosa Roth, on preformed beds. Plots consisted of 4 rows (102 cm centers) x 9.0 m. Treatments were arranged in a RCB design with 4 replications. All plots received Ridomil PC 11 G (11.2 kg form./ha) at planting as a standard fungicide treatment. In-furrow granular treatments (IFGAP) were applied at planting with a John Deere 7100 planter modified to apply pesticides through split hopper boxes. In-furrow sprays (IFSAP) were applied as a directed spray into the seed furrow with a CO2 charged system calibrated to deliver 46.8 liters total spray/ha through Teejet 8002 flat fan nozzles (1/row) at 2.81 kg/cm2. Post-plant broadcast treatments (PRE) were applied with a tractor mounted boom equipped with a compressed air system and calibrated to deliver a volume of 93.6 liters total spray/ha through 2 TX-12 nozzles per row (50.8 cm spacing) at 3.02 kg/cm2. The PRE treatments were applied immediately after planting. Treatment efficacy was evaluated by measuring stand density, damaged plants, numbers of larvae, and estimating skip distances between plants on the 2 inside rows of each plot. From planting (13 May) to 30 May, 6.17 cm of rainfall were recorded.