El Nino-Southern Oscillation effects on peanut yield and nitrogen leaching

Peanut growers in north Florida asked for help in managing the crop to increase yield and reduce yield variability, using information on the pattern of large-scale climate. The objectives of this study were to explore at 4 locations in the peanut belt of Florida and southern Georgia the potential for improving peanut crop performance by altering crop management according to the phase of the El Nino-Southern Oscillation (ENSO). The CROPGRO-Peanut model was used to simulate peanut yield responses to climate and management, The effects of planting date and irrigation management options on the mean and variability of simulated crop yield and nitrogen leaching in different ENSO phases were estimated. This case study showed potential for enhancing peanut yields (1 to 8 %) and reducing yield variability (2 to 12 %) by tailoring planting dates to expected ENSO conditions, while at the same time reducing potential environmental damages from nitrogen leaching by 1 to 11 %. Locations which appeared to have no ENSO linkages currently showed most responses to tailored management in this simulation study. Tailored management calls for later planting during an El Nino, and earlier planting in a La Nina. When planting dates were tailored to ENSO phases, simulations showed at least 10 % lower nitrogen leaching from rainfed production systems in about 70 % of the years. Among ENSO phases, La Nina seasons were shown to have greater nitrogen leaching, with little response to management changes relative to El Nino seasons. Tailored management may be most advantageous in El Nino seasons as a result of higher yields and lower nitrogen leaching. Further research is needed before options derived from simulations and optimization can be recommended and adopted with confidence by growers and extension advisors.