Abiotic Stress Responses in Plants: Present and Future

Abstract

Drought, cold, high-salinity and heat are major abiotic stresses that severely reduce the yield of food crops worldwide. Traditional plant breed-ing approaches to improve abiotic stress tolerance of crops had limited success due to multigenic nature of stress tolerance. In the last decade, molecular techniques have been used to understand the mechanisms by which plants perceive environmental signals and further their transmis-sion to cellular machinery to activate adaptive responses. This knowledge is critical for the development of rational breeding and transgenic strate-gies to impart stress tolerance in crops. Studies on physiological and molecular mechanisms of abiotic stress tolerance have led to characterisa-tion of a number of genes associated with stress adaptation. Techniques like microarrays have proven to be invaluable in generating a list of stress-related genes. Some of these genes are specifi c for a particular stress while others are shared between various stresses. Interestingly, a number of