Fungicides for Exobasidium green spot control on 'Premier' rabbiteye blueberry in North Carolina

摘要

This experiment was conducted on 10-yr-old bushes planted on 4 x 11 ft spacing in a commercial rabbiteye blueberry planting in Pender County, NC. Plots consisted of three adjacent bushes in a row, with untreated bushes between plots. A randomized complete block design was used with five replications, with all plots on two adjacent rows. Spray treatments were applied using a CO_2-powered backpack sprayer delivering the equivalent of 25 gallons per acre (gpa) at approx. 40 psi. A spray boom with two hollow cone nozzles spaced 20 inches apart was used. At each spray date, applications were made in timed passes down one side of each plot. Treatments were applied at bud swell (28 Feb), bud break (13 Mar), pink tip (27 Mar), early bloom (3 Apr) and late bloom (10 Apr). Leaf infections were evaluated on the sprayed side of the center bush in each plot on 14 May by estimating the average number of spots per leaf, and the percent of all leaves with one or more spots. All ripe berries were harvested from thesprayed side of the center bush in each plot on 20 Jun. Berries were sorted visually for the presence of green spot symptoms, weighed and counted. Statistical analysis was performed using PROC ANOVA (wwww.sas.com).