Armyworm And Pepper Weevil Control on Bell Pepper, Spring 1996

Transplants were set 26 Feb, 12 inches apart on 8-inch-high and 32-inch-wide beds of EauGallie fine sand covered with white polyethylene mulch. Each plot consisted of a single row of 14 plants with rows on 5 ft centers. Treatments were replicated 4 times in a RCB design and were applied with a 2.5 gal, hand-held CO2-powered sprayer on 11, 18, 26 Apr, 1, 8, 15, 22, 31 May, 5, 12, 19, 28 Jun, 3 and 10 Jul. The sprayer was outfitted with a single nozzle with a D-5 disk and #45 core delivered 100 gpa at 60 psi. Because of a very heavy population of southern armyworm larvae, weekly applications of Bacillus thuringiensis (Javelin and Xentari alternating weekly) were initiated on 13 Jun. On 20 May and 7 Jun, each plot was rated by two persons for increasing percentage of defoliation by armyworm larvae using the Horsfall-Barratt system. With this system, ratings of 1-12 corresponded to 1-100% defoliation. The ratings were averaged prior to analysis. On 24 Jun, each plot was sampled by dislodging the aphids from the tops of five plants with a 12 inch garden stake into the bottom of a rectangular cake pan painted black and coated with a thin film of vegetable oil. Fruit were harvested on 20 May, 4, 18, 26 Jun, 8 and 17 Jul. The number and weight of undamaged fruit and the number of fruit damaged by armyworm larvae were determined. Fruit were also examined for the presence of surface oviposition scars and larval feeding damage inside, caused by the pepper weevil.