Date of this Version
Plant Disease Management Reports 10, FC096 (2015).
The objective of the trial was to compare fungicide and herbicide treatments for gray leaf spot (GLS) efficacy. Corn was grown under normal, irrigated agronomic practices at the South Central Ag Lab near Clay Center, NE. Soils were a silt loam with 6.7 pH and 1.8% organic matter and the previous crop was corn. Reduced tillage was performed prior to planting. Corn (DKC 64-83 RIB, moderately susceptible to GLS) was planted at approximately 34,000 seed/A on 2 May. Seven treatments were arranged in a randomized complete block design with six replications. . . . Treatments applied at V8 or R1 did not cause phytotoxicity to corn. AUDPC values were significantly lower in plots treated at R1 versus V8, Glyfos herbicide, and the nontreated check. AUDPC values were significantly lower in plots treated with Headline AMP (R1) and Fortix 5 oz (R1) compared to the other treatments. Stay green was significantly greater in plots treated with fungicides at R1 versus V8, Glyfos herbicide, and the nontreated check. Stay green was significantly greater in plots treated with Headline AMP at R1 versus the other R1-applied fungicides. Lodging was significantly lower in plots treated with Fortix 4 oz (R1) and Headline AMP (R1) compared to the other treatments. There were no significant differences between treatments for yield. Data indicated that R1-applied fungicides reduced GLS severity, increased stay green, and protected against lodging.