Physiological Responses of Wheat (Triticum aestivum L.) to Drought Stress

Drought is serious problem in many parts of the world in circumstances of rapid change in climatic conditions especially for rainfed agriculture. Among prevailing abiotic stresses, it is the most significant and severe factor inhibiting plant growth and production. Water deficiency in plant impairs the numerous physiological and metabolic functions. Selection of wheat genotypes that can tolerate water scarcity would be helpful tools for breeding program aiming to development of drought tolerant variety under water limited regions. Rapid development of new wheat varieties with the help of analytical breeding would be the most attractive approach. In this review paper, after the brief introduction about the present scenario of food insecurity, the impact of drought and about the targeted approaches for drought stress, we briefly review the already work done to deal with this environmental calamity (drought). We discussed in detail the important physiological traits (viz. proline content, relative water content, chlorophyll content, cell membrane stability and canopy temperature) having important role in wheat to estimate the drought tolerance and to improve the efficiency of crop breeding. This review paper highlights the role of physiological traits in enhancing the crop yield and their tolerance to water deficiency. The analytical breeding approach followed by the conventional strategies has already been engaged and more need to be employed in future for improving and developing the new wheat varieties, which should be perform better under drought condition. Analytical (physiological) breeding should become an important component of modern wheat breeding research.