The test was conducted on a Maury silt loam located at the University of Kentucky Turf Center near Lexington. The turf was maintained at 0.188-in. mowing height and fertilized with 1.5 lb N/1000 sq ft as urea on Oct and Nov 03, and with 1.0 lb N/1000 sq ft as urea on Jun. The green was intentionally maintained as nitrogen deficient through the test period, in order to evaluate
performance of fungicides under low fertility conditions. Plots m easured 4 ft x 4 ft with 2-ft borders, and were arranged in a randomized complete block design with three replications. Fungicide sprays were applied using a CO2-pressurized hand-held sprayer fitted with Spraying Systems 8003E flat-fan nozzles delivering 1.5 gal/1000 sq ft. Treatments were first applied on 20 May, and
continued biweekly until 28 Jul. Visual estimates of turf quality were taken on several occasions and included deterioration of leaf color and density as well as developing leaf necrosis from several diseases, but excluded damage from dollar spot in the assessments (except 26 Jul). Selected treatments comparing phosphite-based spray programs were evaluated on more occasions
than all other treatments in this trial, in order to compare these treatments as thoroughly as possible. These additional assessments are presented in this report. The level of infestation by Poa annua was visually estimated 11 May, when color differences between the two grass species and the presence of Poa annua seed heads facilitated discrimination. The percent of Poa annua per plot
averaged 41.3 % and did not differ significantly between treatments. Data were analyzed using ANOVA and Waller-Duncan k-ratio ttest, (k=100, P=0.05).
Weather was moderately favorable for disease development. On 7 Jul approximately 50% of the diffuse turf damage in the trial was due to brown patch, 35% anthracnose, and 15% Leptosphaerulina leaf blight. Significant differences in turfgrass quality were apparent among spray programs with phosphite fungicides (Chipco Signature , Alude, Vital, and Resyst). No phytotoxicity or growth regulator effects were noted in the trial.
