Charcoal rot (CR) is an important disease for soybean. Yield loss suppression based on state specialists’ estimates averaged [2.7x10 power 7] tons per year from 1996 to 2007 in the southern states (Arkansas, Kansas, Kentucky, Missouri, Mississippi, and Tennessee). Recent climate model projections indicate average atmospheric evaporative demand (VPD-dry air) will increase roughly 20% over the next 50 years, which will increase crop water use and potentially limit crop growth rates and productivity. Also, global temperatures are predicted to rise by 1.4 to 5.8 degrees C by the end of the twenty-first century (IPCC 2007). Therefore, soybean yields can be expected to be impacted by more severe charcoal rot and abiotic stresses such as water deficit stress and high evaporation demand. However, recent research indicates that disease development was favored under irrigation in infested fields more than previously thought*.

The goal of second year of this project is to determine the change in seed protein and oil quality under both irrigated and rained conditions when soybean varieties with drought tolerance (DT) and charcoal rot severity are used. The humidity and temperature will be monitored the entire season similar to last year. Additionally, the value of dry air effect around the soybean leaves at midday would be evaluated under rainfed condition. At harvest, the seeds protein and oil quality will be assessed per genotype and treatment.

The results of this project would provide producers with information on variety selection for different protein and oil amount under both moisture stress and irrigation. Also, the project findings will lead producers to better management decisions in environments where combined stress from charcoal rot disease and water deficit is present.