Potato Insect Pest Control, 1996

Abstract

Abstract ‘Kennebec’ potatoes were planted 31 May at the Fry Farm, OARDC, Wooster, OH. Plant spacing was 38 inches between rows and 9 to 10 inches between plants. Fertilizer was applied at planting (1750 lb/acre 10-20-20). The Admire 2F (in-furrow) treatment was applied at planting using a CO2compression sprayer at 20 psi with an 8004 flat fan nozzle delivering the insecticide into the seed furrow and on top of the tubers. The field was treated for weed control on 20 Jun with 0.67 lb/acre of Sencor DF. Fungicide, 1.5 lb/acre Penncozeb DF, was applied 11, 24, 29 Jul, 5, 13, 21 Aug, and 6 Sep. Paraquat, 1 qt/acre, was applied 20 Sep as a vine killer. Plots were two rows wide and 40 ft in length, with 9 ft alleys separating plots and 4 ft alleys separating blocks. Treatments were arranged in a RCB design. Foliar treatments were initiated when the first generation larvae were increasing in the plots. Foliar applications of Provado were made 28 Jun and 2 Aug only. All other foliar treatments were applied 28 fun, 12 Jul, 2 and 16 Aug. Cygon 4 E, 1 pt/acre, was added to designated treatments of Fipronil 1.67 SC 12 Jul and 2 Aug to suppress PLH populations. All treatments were sprayed with Cygon 4 E, 1 pt/acre in combination with the 13 Aug fungicide application. Foliar treatments were applied with a tractor mounted drop nozzle boom sprayer delivering 50 gpa at 50 psi with three D-4 hollow cone nozzles/row. Number of eggs, small (instar 1-2), large (instar 3-4) larvae, and adults were counted and percent defoliation was visually estimated in five lm lengths of row per plot weekly. Leafhopper nymphs and aphids were sampled by visually inspecting 25 compound leaves per plot on each sampling date. Potatoes were harvested 11 Oct and graded 15 Oct.