APPROACHES TO IMPROVE STRESS TOLERANCE USING MOLECULAR-GENETICS

Plant productivity is greatly affected by environmental stress factors. In this review, we give an overview of molecular approaches that have been taken to study stress tolerance; in particular, we consider drought, salt and cold stress. Strategies and perspectives in using molecular biology to improve stress tolerance are outlined describing specific examples. Osmotic stress is associated with the synthesis of novel polypeptides and/or osmolytes. The spectrum and action of these different metabolites are summarized. A number of stress-related genes have been characterized and several representatives are discussed. After transforming plants with these genes, the effect of the encoded proteins on altered stress behaviour is examined. If genes with enzymatic functions were chosen for these experiments, complete pathways may be altered and this can implement the production of novel metabolites conferring stress tolerance.