Traits Associated with Drought and High-Temperature Stress and Its Associated Mechanisms in Legumes

Abstract

Developments in crop management practices and novel breeding methods are important to sustain crop productivity for the current and upcoming challenges caused by drought and high-temperature stresses because the occurrence of these stresses during crop growth stages is determinantal to crop yield. Direct selection for yield per se under any abiotic stress conditions is often ineffective because of the low heritability for yield. One of the ways to increase the selection efficiency for stress tolerance is to select for any secondary traits which are easy to measure, presenting high heritability, and correlate highly with grain yield under stress situations. In this chapter, the secondary traits like plant water status, green leaf area duration, limited transpiration, canopy temperature depression, root architecture, early morning flowering, membrane integrity, photochemical efficiency, stem carbohydrate mobilization, and yield-associated traits are discussed. The above plant traits can be quantified under both controlled and field environments. The possibility of converting these traits under controlled environments into a method of quantification at field scale depends on the advancements in allied sectors of sciences, like spectroscopy, remote sensing, aeronautics, and high-end computing facilities. The use of these traits as a selection tool in crop breeding will pave the way for the development of drought and high temperature stresstolerant genotypes.