Beet Armyworm Control in Cabbage, 1985

Abstract

Abstract This experiment was conducted to evaluate three insecticide treatments for controlling beet armyworm larvae. ‘Greenback YR’ variety cabbage was seeded on 24 Sep into single-row beds with 40 inch centers at the Texas Agricultural Research and Extension Center, Weslaco, TX. Soil type was a Willacy fine sandy loam. Plots measured 30 ft by two beds, and were arranged in a randomized complete block design. Plots were inoculated 21 Nov with 48 h old beet armyworm egg masses obtained from a laboratory reared culture. Five plants were selected from the center of each plot and inoculated by attaching three egg masses/plant to a leaf with a paper clip. Five additional plants, located adjacent to the Ave that were inoculated with eggs, were infested with two-week old beet armyworm larvae that had been reared on artificial diet. Each plot received 50 larvae. Treatments were applied on 5 Dec through a C02 powered, ground sprayer at a rate of 5 gal/acre finished formulation. Efficacy was evaluated on 8 and 12 Dec by recording all beet armyworm, cabbage looper, and diamondback moth larvae on the ten plants that had been previously infested with beet armyworm larvae. Since we violated the assumption of normal distribution by infesting only five plants, we utilized the RANKS procedure to weight each plot within a replication according to the number of beet armyworm larvae present.