Apple, Effect of Sevin XLR on Predator Mites And White Apple Leafhopper, 1992

Abstract

Insecticides were applied to mature trees in Fennville, MI (‘Red’ Block) at a rate of 125 gal/acre with an FMC CP 3000 sprayer. Treatments were arranged in randomized complete blocks of 12 trees, 2 replicate samples taken from within each block. Applications were made on 25 Aug and 4 Sep. Rubigan, Captan, and Nova were applied separately to all treatments. At the evaluations on 25 Aug, 2, 8, 16 and 24 Sep, samples consisted of 50 leaves per tree (100 per treatment) picked at random and brushed on a mite brushing machine. Mite predator adults (AF and ZM) were counted under a stereo microscope. WALH evaluations were made by picking 50 randomly selected leaves per replicate (100 per treatment) from the periphery of the tree and counting leafhopper nymphs.