Colorado Potato Beetle Control with Foliar Sprays, 1992

Potatoes were planted on 30 Mar near Middletown, DE. Four row plots, 25 ft long and 30 inch centers, were replicated 4 times in a randomized complete block design. Treatments were applied with a CO2-pressurized ATV 4-wheeled sprayer delivering 45 gal/acre at 40 psi. Treatments were applied on 29 May; 3, 11, 17, and 25 Tun; 1 and 8 Jul. A CPB defoliation rating was taken on 7 Jul. Defoliation injury ratings of 1-5 were indexed as follows: (1) 1-20%; (2) 21-30%; (3) 31-50%; (4) 51-80%; (5) 81-100%. CPB evaluation criteria consisted of visual counts of adults, small larvae (first and second instar) and large larvae (third and fourth instar). Plots were harvested and yield recorded (cwt/acre) on 30 Jul.