CONTROL OF THE SILVERLEAF WHITEFLY ON SQUASH, FALL 2000

Plots were seeded 26 Sep, 12 inches apart within the row on 8-inch-high and 32-inch-wide beds of EauGallie fine sand covered with white polyethylene mulch. Each plot consisted of a single 10-ft long row with rows on 5-ft centers. Treatments were replicated four times in a CRB and were applied with a 2.5-gal, hand-held CO2-powered sprayer at 60 gpa on 29 Nov. The sprayer was fitted with a D-5 disk and #45 core and operated at 60 psi. Prior to spraying, at least five second-to-fourth instar whitefly nymphs were circled on each of five leaves per plot with an indelible marker. Nine days after spraying, the nymphs on each leaf were examined in the field with a hand lens, and the numbers of live and dead nymphs recorded. At 14 DAT spraying, the leaves with circled nymphs were removed, and the numbers of live and dead nymphs were counted in the laboratory using a dissecting microscope.