Chapter 19 - Climate change and their impact on global food production

Abstract

Crop production is influenced by external factors (climate, edaphic, biotic, socioeconomic, and physiographic) and internal factors (genetic). Climatic factors are primary yield determinants due to unpredictable occurrence, difficult management, and heavy losses. Changes in rainfall, atmospheric temperature, the intensity of solar radiation, wind velocity, and concentration of atmospheric gases (CO2, O2, CH4, N2, and SO2) are climatic factors. Major crop losses occur from variations in atmospheric temperature and precipitation. There are tropical and temperate zones according to temperature classification. Crop grown in the temperate zone tends to give higher yield or crop productivity than that of the tropical zone. Increased temperature caused heat stress, and low temperature caused chilling injury to the plants. Plants exhibit morphological, physiological, and biochemical reactions at each growth stage of the crop under temperature stress. Exposure of the sensitive crop growth stage toward very low and high temperature will drastically reduce the yield. Very low rainfall may result in drought, while heavy rainfall can create flood and waterlog, which hampers crop production. The plant itself has a tolerance escape and avoidance mechanism to tackle extreme climatic conditions. Antioxidant defense system, heat-shock proteins/stress proteins, and osmotic adjustment are common mechanisms for the alleviation of all stress conditions.