P-109 - Can Less Mean More?: Effect of Delayed Fungicide Timing and Reduced Applications for Control of Late Leaf Spot on Peanut

North Carolina produces approximately 130,000 acres of Virginia-type peanuts each year. A significant disease of peanut Late leaf spot (LLS), caused by the pathogen Nothopassalora personata, threatens production and can reduce peanut yield by 50% without fungicide applications. Historically, management of LLS consists of 4-6 fungicide applications per season, starting 45–55 days after planting (DAP). In recent years the Virginia-Carolina peanut growing region has seen historically low rainfall in June, delaying disease pressure  of LLS much later in the growing season. Current management costs growers an average of $52/acre, prompting an evaluation of reduced and delayed fungicide programs. Therefore, the objective of this study was to evaluate a reduced number of fungicides and delay onset of fungicide programs in order to develop new recommendations. In 2024,  a field experiment was conducted in Lewiston, NC that consisted of randomized complete block design in a split-split-plot arrangement with four replications. Results showed that delaying the first application from 45 DAP to 60 DAP provided comparable or improved control. Similarly, comparable amounts of control were sustained from the 3 spray program when compared to the 5 spray program. Across all timings and application dates, no significant differences in yield were observed, indicating the findings from this study can be used to recommend later and potentially fewer fungicide applications for peanut growers as we continue to face drier environmental conditions in North Carolina.