Engineering Crops for Enhanced Drought Stress Tolerance: A Strategy for Sustainable Agriculture

Drought stress can reduce agricultural production, which is a challenge considering the food demand due to the increase in world population. To face this challenge, the design of plants with a phenotype of drought stress tolerance is needed. Conventional breeding has been widely used with this goal, but it requires considerable time and resources. Drought stress response and tolerance are complex issues influenced by numerous environmental and genotypic factors. In this review, experiments involving novel biotechnological tools to improve plant breeding are described and discussed. These experiments involve the use of techniques to accelerate breeding cycles and to enhance the selection of superior genotypes. Furthermore, experiments carried out to elucidate the molecular mechanism of drought stress tolerance and to engineer crops to achieve drought stress tolerance using recombinant DNA technology are described. The main traits associated with drought-tolerant genotypes and the response to drought stress at the morphological, physiological, metabolic, and biochemical levels are analyzed. To cope with the complexity of plant drought response, conventional breeding needs to be integrated with novel tools. It is hoped that this will help to achieve sustainable agriculture development; however, the implications of the use of these biotechnological tools, both alone and coupled, need to be analyzed.