Studying Yield and Water Productivity of Maize at Enhanced Level of Temperature Using DSSAT 4.7.5

Climate variability has been and continues to be, the principal source of fluctuations in global food production in countries of the developing world and is of serious concern. Agriculture, with its allied sectors, is unquestionably are highly dependent on weather conditions, any weather aberrations cause atmospheric and other forms of stress and in turn, will increase the vulnerability of these farmers to economic losses. Process-based models use simplified functions to express the interactions between crop growth and the major environmental factors that affect crops (i.e., climate, soils, and management), and many have been used in climate impact assessments. The climatic scenario from A1B scenario 2011-2090 extracted from PRECIS run shows that overall maximum and minimum temperature increase by 5.39°C (±1.76) and 5.08°C (±1.37). A decrease of about 20 quintals was recorded when maximum temperature was enhanced by +4°C and about 10 quintals decreased at +2°C. Enhancement of minimum temperature by +3°C shows a decrease of about 16 quintals in tops weight. Combination of both minimum and maximum temperature remarkably decreased grain yield at (maximum & minimum +2°C) up to 25.41%. Max. temperature lead to staggering in the irrigation water productivity, however, a consistant increase in the irrigation water productivity was realised with an increase in minimum temperature. Dry matter productivity of 50 kg DM /ha/mm [ET] was observed with the increase of 1°C in both Max. and Min. temperatures and the lowest value of (16.7 kg DM /ha/mm[ET]) was recorded when the crop is supposed to grow at enhanced level maximum temperature by +4°C both maximum and minimum temperature. Increase in the both max and minimum temperature by +1°C lead to maximum irrigation water productivity of 22.4 (kg[yield]/ha/mm[irrig]) and the lowest irrigation water productivity of 16.7 (kg[yield]/ha/mm[irrig]) was registerd when both max. as well as min. temp. was raised by +4°C minimum temperature.