Evaluation of Selected Soil and Foliar Insecticides on Sweetpotato Weevil, White Grubs and Banded Cucumber Beetles, 1995

Abstract

Abstract A test was conducted in Hessmer, LA, to determine the efficacy of two soil insecticides and three foliar applied insecticides for control of sweetpotato weevil, banded cucumber beetle, and white grubs. Treatments were arranged in a CRB design with four replications. The cultivar ‘Beauregard’ was planted in Jun. Plots were 4 rows wide (4 feet/row) and 50 ft long. Insecticides were applied at planting day (soil insecticides) and at weekly intervals starting three weeks after transplanting. A CO2 pressurized backpack sprayer was used (30 psi) with a single row boom (20 inches wide) containing three nozzles (Cone Jet SX-10) and calibrated to deliver 25 gpa. Sweetpotatoes were harvested on 13 Oct and field graded into number 1, 2, or 3. From each plot, in each of the 3 grades, 50 potatoes were randomly selected and evaluated for insect damage. The number of potatoes infested with sweetpotato weevil, the number of white grub feeding scars, and the number of holes present caused by banded cucumber beetles (or wireworms) were counted. All data were analyzed by ANOVA and treatment means were separated by DMRT at P = 0.05.