Heat and Drought Tolerance in Wheat: Integration of Physiological and Genetic Platforms for Better Performance Under Stress

Abstract

Heat and drought stress are currently the leading threat on world’s food supply, limiting wheat yield. The extent and severity of stress affected agricultural land is predicted to worsen as a result of inadequate irrigation resources, declining water tables and global warming. Drought/heat tolerance is crucial to stabilize and increase food production since domestication has limited the genetic diversity of crops including wild wheat, leading to cultivated species, adapted to artificial environments, and lost tolerance to stress episodes. Breeding for this trait is complicated as it is controlled by polygenes and their expressions are influenced by various environmental elements and molecular methods such as molecular markers, quantitative trait loci (QTL) mapping strategies, and expression patterns of genes should be applied to produce heat/drought tolerant genotypes. Understanding the mechanism of stress tolerance along with a plethora of genes involved in stress signaling network is important for wheat improvement. Integrating physiology and biotechnological tools with conventional breeding techniques will help to develop wheat varieties with better grain yield under stress during reproductive and grain-Şlling phases. We briefly consider mechanisms of adaptation and highlight recent research examples through a lens of their applicability to improve the efŞciency of wheat under stressful Şeld conditions. Improvement for stress tolerance can be achieved by the introduction of drought and or heat related genes and QTLs to modern wheat cultivars

Keywords

• drought, heat, yield, tolerance, climate change, wheat, stress

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