Evaluation of QoI fungicide mixtures for the control of brown ring patch in southern California, 2008

摘要

The objective of this experiment was to evaluate fungicides for the control of brown ring patch. The experiment was conducted on a putting green located at Torrey Pines Golf Course in La Jolla, CA. The green was an approximate 80/20 mix of annual bluegrass and creeping bentgrass established on native soil. Turf was mowed three times a week at a cutting height of 0.150-in. Irrigation was applied daily according to evapotranspiration needs. Disease development was observed on annual bluegrass in the last week of April and on 2 May, experimental plots (4 ft X 6 ft) were arranged in a randomized block design on the green, using four replicated plots per treatment. Fungicide applications were initiated on 2 May on 14 or 21 day intervals. All fungicide treatments were applied with a CO2-powered boom sprayer fitted with four TeeJet 8002 nozzles at 35 psi, using the equivalent of 2 gallons of dilute fungicide solution per 1,000 sq ft. Disease severity was evaluated on a 0 to 10 scale, with 0=no disease, 5=50% of the plot affected by disease and 10=100% of the plot affected by disease, starting on 2 May and every 7 days afterwards. Severity data was analyzed by ANOVA and mean comparisons were performed using Fisher’s Protected LSD (α=0.05).