EFFECT OF FOLIAR INSECTICIDES ON APHID AND LADY BEETLE POPULATIONS IN ALFALFA SEED, 2002

Plots were established 23 May 2002 on alfalfa planted to 22 inch row spacing on 15 Apr 2001 at the Parma Research and Extension Center, Parma, ID. Plots, 22 x 20 ft, were arranged in a randomized complete block design with four replications. A single, foliar broadcast spray application was made on 10 Jun with a CO2backpack sprayer operated at 30 psi and 15 gpa using 8002VS flat fan nozzles on 22 inch spacing. Aphid and lady beetle abundance was estimated at 3, 7, 14, and 21 DAT by taking 1, 180-degree sweep from each plot on each date. We were careful not to sweep in the same location within in the plot on consecutive sampling dates. Insects were removed from the sweep net, placed in 1-pt glass jars containing 100ml 75% EtOH, and taken to the laboratory where the total number of pea aphids + blue alfalfa aphids and the total number transverse + convergent + other lady beetles recorded. Data were analyzed using repeated measures ANOVA. Dunnett's Procedure was used to separate mean numbers of insects on treated and check plots.