Abstract

                                Globally, agriculture is highly dependent on climate and weather. The deviation from the normal weather including drought, flood, heat waves and cold waves affects all the sectors in particular agriculture sector. Droughts in India are mainly due to failures of seasonal rainfall. Rainfall is one of the most important weather variables that has been influencing the crop growth and yield. Rainfall variability proves to be an influential factor in the yield component of a crop. As Tamil Nadu is located in the tropical climatic condition, the crops productivity is mainly limited by water availability. For the rainfed situation, only source of moisture for crop production is rainfall. Hence, when there is normal or above normal rainfall with even distribution, it leads to increased crop productivity. Simulation models are the most reliable tool for assessing drought on crop production and determine drought stress patterns on crops. CROPGRO-Groundnut model embedded in DSSAT 4.6 was employed to simulate the productivity of groundnut for 37 years (1981-2017) that is grown between June to September in Tamil Nadu and productivity was compared between Deficit, Normal and Excess rainfall years. The results revealed that the average yield of rainfed groundnut was greater for Excess rainfall years (2166 kg ha-1) followed by normal (1772 kg ha-1) and deficit years (1161 kg ha-1). The coefficient of variation in groundnut productivity was high during deficit (10 %) years compared to excess (5 %) and normal (3 %) years

Key words : Drought; DSSAT; Rainfed; Groundnut; Productivity