Genetic engineering for abiotic stress resistance in crop plants

Abstract

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.

Monitoring Expression Profiles of Rice Genes under Cold, Drought, and High-Salinity Stresses and Abscisic Acid Application Using cDNA Microarray and RNA Gel-Blot Analyses

“…To overcome these limitations and improve crop yield under stress conditions, it is important to improve stress tolerance in crops. The responses of plants to various abiotic stresses have been important subjects of physiological studies (Levitt, 1980) and, more recently, of molecular and transgenic studies (Bajaj et al, 1999;Hasegawa et al, 2000;Zhang et al, 2000). The identification of novel genes, determination of their expression patterns in response to the stresses, and an improved understanding of their functions in stress adaptation will provide us the basis of effective engineering strategies to improve stress tolerance (Cushman and Bohnert, 2000).…”

Whole-Genome Mapping of Agronomic and Metabolic Traits to Identify Novel Quantitative Trait Loci in Bread Wheat Grown in a Water-Limited Environment

“…Plants are known to adjust morphologically, physiologically, and biochemically to water stress (Bohnert et al, 1995;Zhang et al, 2000;Vinocur and Altman, 2005). Epicuticular wax may accumulate, causing leaves to be glaucous, stomatal resistance may increase to reduce water loss, and root systems may adjust to increase water uptake either at depth or from intermittent rainfall events.…”

Heterology Expression of the ArabidopsisC-Repeat/Dehydration Response Element Binding Factor 1 Gene Confers Elevated Tolerance to Chilling and Oxidative Stresses in Transgenic Tomato

“…Tomato is generally considered a chillingsensitive plant (Saltveit and Mangrich, 1998). Genetic engineering technology has already been effectively used as a relatively fast, precise, and often costeffective means of improving stress-tolerance in certain plant species (Holmberg and Bulow, 1998;Bajaj et al, 1999;Zhang et al, 2000;Zhang and Blumwald, 2001). It would be interesting to evaluate the effect of overexpressing CBF1 protein in a chillingsensitive plant.…”