The Oklahoma Peanut Leafspot Model is a weather-based management tool which can be used to schedule fungicide applications for early leafspot, a foliar disease of peanuts. The model was developed by OSU plant pathologists and based on field studies conducted at a number of sites in Oklahoma during 1990-1995. It is based on the accumulation of "infection hours", periods during which temperature and humidity conditions are favorable for disease development. Using weather data from the Oklahoma Mesonet, the Model calculates the number of infection hours which have occurred since 30 days after planting or since the start of the last unprotected period, whichever is later. If the number equals or exceeds 36 hours, the Model recommends a fungicide application.

All users are strongly urged to read the Model Description for further instructions on how to utilize the spray advisory, including proper fungicides to apply. The Oklahoma Peanut Leafspot Model will run from May 1 through October 31; it is updated daily and should be available at this web site by 11 a.m. CDT each morning.

To utilize the Model, please go to the Site-Specific Interactive Model section below and follow the instructions. You will need to enter the planting date for your peanuts as well as the date of your last fungicide application this season, if it has occurred. Note that other foliar diseases besides early leafspot may occur that are not controlled well using this model. Growers need to monitor their fields for such diseases. Consult the Images and Related Links sections for further information.

DISCLAIMER

As with any pest management model, the Oklahoma Peanut Leafspot Model is to be regarded as only a tool in making fungicide application decisions. It is not intended to replace the best judgment of the grower in making such decisions.