Colorado Potato Beetle Control, 1993

Abstract

Abstract Seven insecticides were tested at the MSU Montcalm Research Farm in Entrican, MI. Potatoes were planted 12 inches apart with a 34 inch row spacing on 6 May. Plots 45 feet long by three rows wide were arranged in a randomized complete block design with four replications. Plots were separated by at least 6 feet of bare ground. The Admire in-furrow treatment was applied with spray bottles on 6 May. Foliar treatments were applied on 23, 30 Jun/2 and 7 Jul using a tractor-mounted sprayer at 30 gal/acre and 45 psi. Light rain interrupted spraying on 30 Jun; remaining treatments were applied on 2 Jul AC303.630 at 5 gal/acre was applied with a CO2 sprayer with a 3-nozzle hand-held boom. Two plots of Cryolite received additional sprays on 4 and 12 Aug. These plots were removed from yield analysis, but were included in analysis of beetle numbers. Two randomly selected plants from the middle row of each plot were sampled for CPB on 28 Jun, 6 and 12 Jul. An outer row was sampled in 5 plots because the middle row had few plants. A visual defoliation assessment was done on 6 and 12 Jul. Potatoes were harvested on 14 Sep, separated by size and weighed.