Control of Early Season Tobacco Budworms on Cotton in Southern North Carolina, 1993

Abstract

Abstract Cotton was planted on 3 May in a Goldsboro fine sandy loam near Richlands, NC. Fertility and weed management programs followed NCSU recommendations with 0.6 lb (AI)/acre Temik 15G applied in furrow at planting. Plot size was 6 rows (38 inch centers) × 50 ft with 8 ft alleys. A RCBD with 5 replicates was used. Treatments were applied with a backpack-type CO2-pressurized sprayer calibrated to deliver 8 gal total volume per acre at 50 psi with a single TX-8 Spraying Systems® nozzle per row. Applications were made on 8, 14, 21 and 29 Jun. The Ovasyn treatment was initiated at pinhead square and received a total of 4 applications. All remaining treatments were initiated at early tobacco budworm egg hatch on 14 Jun. Subsequently, the Design and Curacron treatments were again applied on 21 and 29 Jun for a total of 3 treatments; all remaining treatments were applied a 2nd time only on 21 Jun for a total of 2 applications. The entire test was oversprayed with Orthene 75S at 0.4 lb (AI)/acre on 4 Jun. Twenty five terminals from each plot (125/ treatment) were inspected for eggs and larvae and 25 squares per plot inspected for damage and larvae on 7 Jul. On 7 Jul, the first 3 fruiting positions (oldest) on each plant were removed from the treatment labeled “square removal.” At the time of fruit position removal, plants averaged 28.4 inches tall, plant stand was 31.3/10 ft, total nodes were 13.9, nodes above white bloom were 8 and total number of fruit was 13.4 per plant. Plots were harvested with a John Deere 1 row mechanical picker from the middle 2 rows on 13 Oct.