Pear, Grape Mealybug Control, 1990

Mature pear trees were sprayed with a handgun operating at 600 psi to evaluate pesticides for early season control of GMB. Plots consisted of 6 single-tree replicates in randomized block design. Treatments were evaluated for GMB control by counting the infested shoots per 10-shoot sample per replicate on 3 May and by rating 50 fruits/replicate at harvest for presence of nymphs in the calyx. Fruit with no nymphs present were rated 0, those with 1 or 2 were rated 1 and those with >2 were rated 2. PP nymphs were counted from a 50-leaf sample per replicate collected from fruiting spurs. Nymphs were brushed from leaves onto 5-inch glass disks and counted under magnification. Treatment schedules are presented in tabular form below and include applications at delayed dormant (20 Mar), clusterbud (3 Apr) and petal fall (24 Apr).