EVALUATION OF SOIL AND FOLIAR INSECTICIDE TREATMENTS FOR THE CONTROL OF LEPIDOPTERAN PESTS IN CABBAGE IN VIRGINIA, 2007

Abstract

The objective of our experiment was to assess the efficacy of various soil-applied and foliar insecticides to control lepidopteran pests on cabbage. Treatments were arranged in a RCB design with four replicates. Cabbage was transplanted on 5 Sep at the Virginia Tech Eastern Shore AREC near Painter, VA. Plots consisted of 1 row 20 ft (6.1 m) long with unplanted guard rows on each side. Rows were planted on a 3 ft row center (0.9 m) in a 4 tier field design with 8 ft (2.4 m) alleys between tiers and a 16 ft (4.9 m) center alley. All plots were maintained according to local standard practices. All insecticides were applied with a CO2 backpack sprayer set at 40 psi. Soil insecticide treatments were applied to transplants on 6 Sep with a one nozzle boom directed at the base of each plant. Each plant received 125 ml of spray. All foliar treatments were applied on 19 Sep and 1 Oct at 48 gpa with a 3-nozzle boom equipped with D4 tips and 45 cores. The number of lepidopteran larvae was recorded per 5 randomly selected plants in each plot on 24 Sep and 5, 10 and 23 Oct. Also on 5 Oct, when cabbage heads were forming, the total number of damaged heads in each plot was recorded. At harvest on 19 Nov, the number of marketable heads per plot was recorded after detailed visual inspection of each head. All data were analyzed using ANOVA. Proportion data were arcsine square root transformed prior to analysis. Means were separated using Fisher’s Protected LSD at the 0.05 level of significance.