Impact of climatic variability and climate change on maize productivity in north India

Global warming poses a potential threat to agricultural production and productivity. Maize (Zea mays L.) is one of the most important cereals of the world and provides more human food than any other cereal. The study reported in this paper, uses field experiments and simulation models to understand the impact of changing climate on growth and yield of maize plant. In field environment, growth and yield of maize was greatly affected by temperature changes associated with sowing dates. Yield was reduced in late sown crops due to the harmful effect of chilling temperature. Application of irrigation had positive effect on crop growth. Biomass and grain yield as well as other yield attributes were higher in irrigated treatments than the rainfed one. Info Crop model satisfactorily simulated crop phenology, leaf area index, dry matter production and yield of maize in Delhi. Impact assessment of maize yield to temperature rise showed reduction in yield in both Delhi and Patna with atmospheric temperature rise during the kharif season with percentage reduction was similar in both locations. In rabi crop, future temperature increase initially showed a positive response up to 2°C. Climate change is projected to reduce kharif maize yield in India, however, projected increase in rainfall may be beneficial in some locations during rabi season.