Laboratory Bioassay of Systemic Insecticide Treated Tomato Foliage on Colorado Potato Beetle, 1981

Tomatoes were seeded in rows 12 inches apart (30 seeds/ft) on April 8 at the Coastal Plain Station of the University of Georgia, Tifton. The tomatoes were pulled Jun 1 and shipped to the Vegetable Research Branch, OARDC, Fremont, OH. These were transplanted at Fremont into loam soil on Jun 5 in rows spaced 5 ft apart with 11 inches between plants. The experimental design was a randomized complete block with 4 replicates. Treatments consisted of single 40 ft rows. There were no guard rows. Pre-transplant treatments received broadcast applications of granular systemic insecticides that were irrigated into the soil on May 18 in GA. Post-transplant treatments received granular systemic insecticides applied in single 1 inch furrows ca 6 inches to the side of the plants on Jun 11 in OH. On Jun 16, 23, 30 and Jul 8, young foliage was collected from each plot and stored at ca 45°F until it was fed to early instar Colorado potato beetle (CPB) larvae in 9 inch glass petri dishes lined with moist filter paper. Larvae were allowed to feed 2-3 days at ca 72;F and then mortality was recorded. Larvae used in the bioassay were collected from C-37 tomatoes in Wooster, OH. Foliage from each plot was bioassayed with 5 larvae.