Plant Pathology Department


Date of this Version



Plant Disease Management Reports 10, FC098 (2015).


Copyright © 2015 The American Phytopathological Society. Used by permission.


The objective of the trial was to compare industry fungicide programs with the microbial Regalia Rx plus fungicide tank mixtures 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. Reduced tillage was performed to the field prior to planting. Corn (DKC 64-83 RIB, moderately susceptible to GLS) was planted at approximately 34,000 seed/A on 20 May. Seven treatments were arranged in a randomized complete block design with six replications. . . . Wind lodging was significantly reduced when plots were treated twice with Headline plus Regalia compared to plots treated once and the nontreated check. Generally, lodging was reduced with Headline applied twice compared to treatments applied once. Yields were nonsignificant between fungicide treatments and the nontreated check. However, yields were significantly higher in plots treated once with Regalia plus Quadris (V5) and plots treated twice with Headline versus those treated once with Headline or Quadris (V5) alone. Both Regalia plus Headline and Headline applied twice reduced overall GLS severity, wind lodging, and increased yields.