Abiotic Stresses in Agriculture: An Overview

Abstract

Agriculture production and productivity are vulnerable to abiotic stresses. These stresses emerge due to drought, temperature extremes (heat, cold chilling/ frost), radiation (UV, ionizing radiation), floods in addition to edaphic factors which include chemical (nutrient deficiencies, excess of soluble salts, salinity, alkalinity, low pH/acid sulfate conditions, high P and anion retention, calcareous or gypseous conditions, low redox, chemical contaminants—geogenic and xenobiotic), physical (high susceptibility to erosion, steep slopes, shallow soils, surface crusting and sealing, low water-holding capacity, impeded drainage, low structural stability, root-restricting layer, high swell/shrink potential), and biological (low or high organic contents) components. These stresses are the major challenges for production of crops, livestock, fisheries, and other commodities. Only 9% of the world’s agricultural area is conducive for crop production, while 91% is under stresses which widely occur in combinations. While losses to an extent of more than 50% of agricultural production occur due to abiotic stresses, their intensity and adverse impact are likely to amplify manifold with climate change and over exploitation of natural resources. Fragile agroecosystems like the dryland areas are highly vulnerable to such disastrous impact. To mitigate the effects/impact of multiple stressors, proposed strategies include improved agronomic management, while the breeding of stress tolerant genotypes can enhance capacity for adaptation to stress environments. However, a holistic integrated multidisciplinary approach in systems perspectives is a need of the hour to get the best combination of technologies for a particular agroecosystem. Therefore, this compendium through different comprehensive chapters conveys relevant updates on trends in abiotic stresses and their impact in addition to scientific interventions for stress management through mitigation and adaptation options. The compendium also explains scope for modern science to mitigate abiotic stresses and improve adaptation through genetic improvement and some of the policy support endeavors. The way forward includes information on implementation of existing technologies and gaps to be filled through future research for abiotic stress management.