ABSTRACT
The stability of crop yields is challenged by a variety of abiotic and biotic stresses during each growing season. Adverse environmental conditions such as drought, extreme temperatures, submergence and soil nutrient deficiencies or mineral toxicities constitute important abiotic stress concerns. These impact yield stability directly through their effects on crop establishment, growth and yield, and indirectly through their influence on the nature and intensity of incidence of biotic stresses such as diseases, insects and weeds. Drought and high temperatures are expected to adversely impact crop yields, and consequently food security, even more intensely in the future based on predicted changes in climate. Over the last 1400 years, the period from 1982 to 2012 is identified to be likely the warmest 30-year period in the Northern hemisphere, and the warming of global surface temperatures is likely to exceed 2˚C by the end of the twenty-first century relative to the nineteenth-century baseline (IPCC, 2014). While changes in precipitation are predicted to be not uniform across the globe, many mid-latitude and subtropical dry regions are likely to experience decreased precipitation. Without proper adaptation measures for managing crop production, climate change will have significant impacts on crop yields, leading to food insecurity and the breakdown of food systems, especially in developing nations. It can also affect the geographical distribution of crop species.
