**6. Conclusion**

Sustainable crop production to feed exponentially growing population is the major challenge to the scientific communities in the current global climate change scenario. Out of many productivity-limiting factors, drought stress is one of the most critical factor and of prime importance in the context of decreasing water availability for crop production. Water deficit leads to cellular damage and triggers an array of signaling pathways which in turn activate synthesis of gene transcripts associated with protective functions. In general, wilting occurs owing to physiological responses such as reduced turgor pressure, gaseous exchange, mineral assimilation and overall growth. The prominent result of these is reduced photosynthetic rate Many plant species are inherently equipped with drought tolerance mechanisms such as reduction in leaf area and canopy resistance. Both these mechanisms induce tolerance by cutting off excessive absorption of indecent light as a result of reduced surface area exposed to the incident radiations. In order to select for a tolerant genotype and/or traits conferring tolerance, robust phenotyping is a must. Marker assisted breeding to incorporate drought tolerance conferring quantitative trait loci (QTL) has proven to be effective and efficient. In addition, the knowledge generated by "OMICS" techniques (genomics, proteomics, transcriptomics, epigenomics and metabolomics) and transgenomics are potent and significant tools that would enable a researcher to develop an effective strategy for crop improvement programs in a less timeconsuming cost-effective manner. So, an integrated approach will provide better understanding of mechanisms underlying drought stress and plants' response to it, and help in developing genotypes for dry environments in order to reduce the threat to global food security.
