Use of ENSO Forecasts to Select Nitrogen Fertilizer Application Strategies for Winter Wheat in Alabama.

El Niño Southern Oscillation (ENSO) has a strong impact on winter crops in Alabama (AL). Wheat is basically grown during winter as cash crop and sometimes also as fodder or grain crop in AL. Thus, it is very necessary to understand the impact of variability in climate factors due to the different phases of ENSO and its effect on yield of crops grown in winter especially wheat which provides a range of yields based on fluctuations in temperature and precipitation. Wheat yields in winter also vary based on time and rate of N fertilizer application. After the calibration of the model, the Seasonal Analysis Program of DSSAT 4.5 crop model suite was used for this study to understand the variations in wheat yields under different combinations of N application strategies. Six different combinations of N application strategies regarding time and rate of applications were compared for better yields in different ENSO phases in two locations of North and South AL. Simulated yields in past sixty years were analyzed to select the suitable N application strategy under El Niño and La Niña phases of past 60 years for better wheat yields. The Japan Meteorological Agency Index  was adopted to classify the weather data of past sixty years. The study showed differences in wheat yields were due to the distinct differences in temperature and precipitation during winter in different ENSO phases. The best N application strategy was selected after comparisons of yields under ENSO affected years.