Fungicide efficacy for control of DMI-resistant Monilinia fructicola on peach in middle Georgia, 2008

摘要

Fungicides were evaluated for control of brown rot in a mid-ripening experimental peach variety (USDA selection 88P2251) located at the USDA Fruit and Nut Research Center (Byron, GA). Chemicals were applied with an airblast sprayer(60 gal/A spray volume) on 10 and 17 Jul (pre-harvest sprays). Treatments included an untreated control, Pristine (boscalid and pyraclostrobin), PropiMax (propiconazole) + Abound (azoxystrobin), Rovral (iprodione), PropiMax + Captan, ProPhyt +Captan, and Captan. Four replications of each treatment were applied to a randomized complete block design, with each plot consisting of four trees; the outer two trees in each plot were not utilized for ratings. Unsprayed rows were left between eachspray row. All cultural practices were in keeping with peach production methods commonly observed throughout the Southeast. Earlier in the season, maintenance sprays for scab (Bravo WeatherStik 6F at 4 pt/A at shuck split and YellowJacket Sulfur 90 WP at 9 lb/A through all cover sprays) were applied to all treatments, including the untreated control. At full maturity, 39 asymptomatic fruit were harvested from each plot for rot assessments (24 Jul). The fruit were placed on plasticproduce trays (ambient room temperatures; air-conditioned room; ~77 F). Rot incidence was recorded at four and seven days after harvest.