Implementation of the PeanutFARM Website to Deliver Irrigation Scheduling, Improved Methods of Peanut Maturity Determination and Disease Prediction to Peanut Growers

A trial was established to evaluate an adjusted Growing Degree Day (aGDD) model for peanut to improve the accuracy of maturity determination. The model was developed by Dr. Diane Rowland ( currently peanut physiologist at the University of Florida) and Dr. Wilson Faircloth ( currently with Syngenta) when they were research scientists with the USDA-ARS National Peanut Research Lab. The model is now being run as a part of the "Peanut FARM" web site. 
Peanut cultivar and planting/harvest date studies were conducted to further validate the utility of the adjusted growing degree day (aGDD) maturity model for predicting optimum maturity in peanut. Four peanut cultivars (Georgia-06G, Georgia-09B, Georgia -12Y, and Florun-107) were evaluated. Cultivars were planted on April 28 and May 12 at a seeding rate of 6 seed per foot. Adjusted degree day hours were calculated and assessed for maturity determination as cultivars reached 120 after planting. Cultivars were dug based on 2400, 2500, 2600, 2700 accumulated degree day hours and compared to currently used maturity profile board. Digging dates for the April 28 and planting were Sept 15 (2400), Sept 19 (2500), Sept 30 (2600), and Oct 10 (2700); and for the May 12 planting date were Sept 25 (2400), Oct 7 (2500), Oct 16 (2600), and Oct 30 (2700).
Yield data has been collected, and grade data were collect and analyzed. Data analysis indicated a three-way interaction between planting date, cultivar and harvest timing. Results indicated 2500 aGDD hours to be the optimum maturity of most cultivars evaluated. Grades increased with aGDD hours which was expected.