Genetic engineering for abiotic stress resistance in crop plants

Drought, extreme temperatures and high salinity are major limiting factors for plant growth and crop productivity. In their quest to feed the ever-increasing world population, agricultural scientists have to contend with these adverse environmental factors. If crops can be redesigned to better cope with abiotic stress, agricultural production can be increased dramatically. Recent advances in understanding crop abiotic stress resistance mechanisms and the advent of molecular genetic technology allow us to address these issues much more efficiently than in the past. This paper reviews the most significant achievements of the genetic engineering approach to improving plant abiotic stress resistance and discusses future prospects in transgenic research. Improved resistance to drought, salinity and extreme temperatures has been observed in transgenic plants that express/overexpress genes regulating osmolytes, specific proteins, antioxidants, ion homeostasis, transcription factors and membrane composition. Although the results are not always consistent, these studies collectively foretell a scenario where biotechnology will arm our future crops with new tactics to survive in hostile environments. Further experiments are needed to determine if the achieved increases in stress tolerance are applicable to agriculture.