Abstract
Development of plant varieties with a high level of tolerance to abiotic stresses is crucial for establishing full yield potential and to stabilize production. Due to the multitude of abiotic stresses and their complex genetic control the progress of breeding for tolerance to abiotic stresses using conventional approaches has not been very rewarding. Recent advances in cellular and molecular biology have made it possible to clone important genes and mobilize them in any organism across barriers of sexual hybridization for stable expression and transmission. All living organisms have evolved mechanisms for avoidance and/or tolerance to one or more of the abiotic stresses. Plants producing crucial enzymes or proteins from various organisms involved in abiotic stress tolerance mechanisms have shown significant advantage over their wild type controls under stressed environment. The enhanced level of compatible osmolytes, radical scavengers and other transgene products correlated with the degree of tolerance. Further understanding of the molecular mechanisms of stress perception, signal transduction and response by plants and other organisms may help to engineer plants with high levels of tolerance to multiple stresses. Perspectives and additional approaches for further improving the tolerance to abiotic stresses through genetic engineering are discussed.
