Godsey Ag

Variable Rate Peanut Fungicide


Southwest peanut growers continue to try to increase yields and reducing input costs. Perhaps the largest input in a peanut crop is fungicide applications. This is especially true for areas in the region that have high disease pressure from sclerotinia. On average, a single fungicide application costs $50-60/acre to help control the disease. Precision ag technologies (GPS, variable rate applicators, aerial imagery, etc.) are currently available that provide producers with application options.Currently we have two strategies of defining management zones when it comes to variably applying fungicide to control sclerotinia: 1) grid sampling to determine sclerotia concentration in the soil or 2) using aerial imagery from past years. Either method has been proven to be effective and can significantly reduce fungicide cost.

Figure 1. Sclerotia concentrations on a 50 ac field in SW Oklahoma. This map illustrates the difference in sclerotia counts throughout the field. Any area with sclerotia counts >1 would be considered a high disease area.


Figure 2. Near infra-red image of the same field taken in September. This image could be used to delineate management zones for future years. The darker areas in the image have more sclerotinia.












With variable rate fungicide applications you can typically save 40-60% on fungicide to control sclerotinia. Another benefit of variable rate fungicide application is that we can use the highest labeled rate in the highest disease pressure areas. Research has shown that higher application rates will increase yield more compared to lower rates on fungicide labels.Also, historic yield maps can be used to help confirm high and low disease areas.

 What you receive: