On-Farm Evaluations of Reduced Input Fungicide Programs in Peanut Fields with Low, Moderate, or High Levels of Disease Risk

Abstract

ABSTRACT In 2003, 2004, and 2005 standard and reduced input fungicide programs were evaluated throughout the peanut production region of Georgia for control of early leaf spot (Cercospora arachidicola), late leaf spot (Cercosporidium personatum), and southern stem rot (Sclerotium rolfsii). Disease risk was determined for each field based on the cultural practices implemented and ranged from low to high. Six to eight fungicide applications were made in the standard programs, versus three to six applications in reduced programs. Leaf spot ratings were higher for the reduced programs in five of the fourteen trials with substantial defoliation occurring in one trial. Overall, southern stem rot control for the reduced programs was equal to or better than that for the standard program, which could be attributed to the differences in fungicide selection or timing. Pod yields for the reduced programs were equal to or greater than the standard programs in all but one trial. Net returns were higher for the reduced programs in half of the trials; however, the reduced program resulted in lower net returns in one trial in 2004. Our results indicate that reduced input fungicide programs can be used to adequately manage fungal diseases of peanut without compromising yield or profitability, and that the use of cultivars with moderate levels of disease resistance may enhance disease control.