Colorado Potato Beetle and European Corn Borer Control with Insecticides, Pasquotank Co., Nc, 1993

Abstract

Abstract ‘Atlantic’ potatoes were planted in early Mar for Tests 1 and 2 near Elizabeth City, N.C. on 42 inch centers. Plots in Test 1 were 14 ft long and in Test 2 20 ft long, with single row spacing replicated 4 times in a randomized complete block design. Alleys of 5 ft were used between replicates within rows. Treatments in Test 1 and Test 2 were applied with a CO2 pressurized backpack sprayer with a single hollow cone nozzle (18X) operated at 60 psi to deliver 54.5 gal/acre. In Test 1 all treatments were applied on 5, 11 and 18 May. All treatments were applied to Test 2 on 5 May, with the exception of the 1/6 lb rate of Trigard 75WP in combination with Trigard 75WP at 1/3 lb rate which received the combination low rate (1/6 lb) 6 days later. On 11 May applications were applied to all treatments except for Trigard 75WP at the 1/3 lb, 2/3 lb (egg only) and Trigard 75WP 1/3 lb (egg only) plus Trigard 75WP at the 1/6 lb rate. At this time the low rate of the combination Trigard 75WP 1/6 lb rate was applied. Imidan 50WP at 2 lbs and Imidan 50WP at 2 lbs plus Butacide 8EC at 0.5 lbs was applied on 5, 11 and 18 May. Test 1 and Test 2 counts of CPB on 3/hill plots were made 11 and 18 May. Small larvae were assumed to be first and second instar, and large larvae, third and fourth instar. Visual CPB damage ratings were made 18 May and 15 Jun. Visual ECB ratings were made and potatoes harvested and yields recorded 15 Jun.