Evaluation of Insecticides Against Lepidopterous Pests During Bloom on Blueberries, 1995

This study was conducted in a ‘Bluecrop’ blueberry field in full production near Whitesbog, NJ. Blueberry bushes were approximately 5 ft tall and spaced 9X4 ft apart. Treatments were arranged in a RCB design, replicated 5 times with each replication consisting of 6 bushes in 2 rows. Two unsprayed rows between blocks and 5 unsprayed bushes between treatments within a block served as buffers. Insecticides were applied with a Mighty Mac model PS-322T garden sprayer equipped with a handgun calibrated to deliver 200 gal/acre at 75 PSI. Insecticides were applied once on 16 May approximately at 50% bloom. GM eggmasses were obtained from USDA-APHIS facility at Otis Air Base in Cape Cod, MA, to augment larval populations in the field plots. Eggmasses were stapled to the bush on 3 May at the rate of 1 eggmass per bush. Eggmasses began to hatch on 6 May and larvae were well distributed on the bushes within a week after hatching. Larval populations were assessed by sampling 25 clusters from each of 4 randomly selected bushes/replicate for a total of 100 leaf and flower clusters/replicate on 15 May (pre-treatment count) and 26 May (post-treatment count). Leaf and flower clusters were randomly selected from the top, middle and bottom thirds of each bush.