INTEGRATED CROP MANAGEMENT AND BREEDING FOR IMPROVING YIELD STABILITY UNDER ABIOTIC STRESS: A REVIEW

Abstract

Abiotic stresses such as drought, heat, salinity, water logging, chilling, and nutrient imbalance limit crop productivity and yield stability throughout the world. The increasing severity and unpredictability of abiotic stresses due to climate change limit crop growth, reproduction, resource-use efficiency, and food production. Increasing crop productivity under such stresses needs an integrated approach consisting of stress-tolerant crop management along with the genetic improvement of stress-resistant crop varieties. Integrated crop management (ICM) involves efficient water and nutrient management, conservation agriculture, improved soil organic matter content, crop diversification, optimal timing of crop planting, precision farming, and biological intervention. Genetic improvement of crops complements ICM with the development of crop genotypes with enhanced root morphology, water use efficiency, heat stress tolerance, ion homeostasis, reproductive tolerance, and yield stability under environmental variability. Genetic improvement of crops involves conventional breeding, marker-assisted selection, genomic selection, QTL mapping, genome editing, and high-throughput phenotyping to provide new ways of stress tolerance improvement. The recent developments in genomics, phenomics, and artificial intelligence help in the discovery of useful alleles and the selection of stress-tolerant genotypes in targeted stress environments. This review discusses the physiological basis underlying the responses to abiotic stresses, assesses integrated agronomic/breeding approaches, and explores avenues for integrating management with genetic solutions. In this review, the systems approach is outlined, whereby resilient germplasm, site-specific crop management, climate-smart decision making, and participatory evaluations can be brought together to maintain crop productivity. The implementation of these approaches in an integrated manner will enhance the stability of crop yield and efficiency of resource use.