INSECTICIDE EFFICACY AGAINST WORM PESTS IN LETTUCE, 2010

The objective of the study was to evaluate the efficacy of various formulations of chlorantraniliprole compared to a standard worm control insecticide spinetoram (Radiant) and an untreated control for early season worm pests on iceberg head lettuce under desert growing conditions. Head lettuce (KEEPER) was direct seeded on 3 Sep 2010 at the University of California Desert Research and Extension Center, El Centro, CA into double row beds on 40 inch centers. Stand establishment was achieved using overhead sprinkler irrigation, and irrigated with furrow irrigation thereafter. Plots were four beds (13.3 ft) wide by 40 ft long and bordered by one untreated bed. Five replications of each treatment were arranged in a RCB design. Insecticidal compounds, formulations and application rates along with treatment dates are provided in Table 1. The in-furrow, at-planting application of Durivo was injected 2 inches below the seed in 15.6 gpa of H2O on 2 Sep. All other insecticide treatments were foliar sprays applied with a Lee Spider Spray Trac 4-row sprayer with three TJ-6