Project Number: 8042-22000-288-04-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 1, 2018
End Date: Jun 30, 2019
Overall research objective is to gain knowledge necessary for sound pest and resistance management practices for Colorado potato beetle (CPB), including use of alternative/selective insecticides. Objective 1: Investigate baseline geographic variability in tolerance of CPB to alternative insecticides in order to predict the rate at which resistance might develop. Objective 2: Determine field efficacy of alternative insecticides on CPB and potential non-target effects on natural enemies of CPB.
Objective 1: Investigate baseline geographic variability in tolerance of CPB to alternative insecticides in order to predict the rate at which resistance might develop: Insects from Northeastern, Mid-Atlantic and Pacific Northwestern populations of CPB will be collected, transported to the laboratory, and reared on greenhouse grown and insecticide-free potatoes (var. ‘Kennebec’). Neonate CPB (<24h post-hatch) will be exposed to 6-8 concentrations of the alternative insecticides (provided by Virginia Tech and UMD/Dively Lab) incorporated into a solid diet, held in growth chamber at 25°C (as described by Olsen et al. 2000). Mortality will be assessed at 24h intervals and LD50 calculated for each insecticidal product and collection locale. Objective 2: Determine field efficacy of alternative insecticides on CPB and potential non-target effects on natural enemies of CPB: Conduct field evaluations of efficacy on CPB, and evaluate the residual toxicity of various selective insecticides for CPB (adults and larvae), spined soldier bug (adults and nymphs), spotted pink lady beetle (adults and larvae), and Lebia ground beetle (adults and larvae). These species are available at Beltsville, the first two already in laboratory rearing. Field plots measuring a single row of untreated potato, 10 ft long and spaced 40 inches apart, will be arranged in a randomized block design with four replicates per treatment and CPB eggs, larvae, and adults will be monitored over time. Bioassays using excised leaves from these field experiments will be used to determine residual efficacy of materials on CPB and its predators 24 h, 7 d and 14 d after foliar application. Bioassays will be carried out using a method similar to that used in Wimer et al. (2015).