Engineering crop plants against abiotic stress: Current achievements and prospects

Allah Bakhsh,Tahira Hussain

doi:10.9755/ejfa.v27i1.17980

Abstract

The growth, development and productivity of crop plants is negatively influenced by abiotic stresses like drought, salinity, heat and chilling leading to significant losses in crop yield. The modern technology of genetic engineering has enabled the scientists to move genes from distant sources into crop plants to develop resistance against insect pests, weeds and invading pathogens, some of them have already been commercialized. Similarly, efforts have been made to develop crop plants with enhanced tolerance against drought, salinity and chilling and waterlogging stress. Engineering crops against abiotic stresses has always been a challenge as this character is controlled by multigenes. The stress signaling and regulatory pathways have been elucidated using advanced molecular approaches and genes encoding tolerance to drought, salinity and chilling stress are being introduced in crop plants of economic importance using transformational technologies. The present review focuses the recent advances made in the development of transgenic crop plants of commercial importance with enhanced tolerance to abiotic stress; also the future prospects of stress tolerant crops have also been discussed.

Highlights

An external factor incurring negative influence on the plant can be defined as stress Levitt (1972)
Earlier reviews contain limited information about field crops engineered with abiotic stress related genes; here we have focused on the endeavors achieved in crop plants of economic importance, the abiotic stress tolerant crops tested in field conditions have been discussed
Over expression of OsDREB in rice resulted in gene activations and regulation involved in drought, high-salt- and cold-responsive gene expression Wheat cultivar transformed with atDREB1A under stress inducible promoter showed increase drought tolerance Expression DREB1A /(CBF3) in transgenic rice showed enhanced tolerance to salinity and drought Overexpression of ZmDREB2A in Maize under stress inducible as well as constitutive promoter encoded stress tolerance Transgenic tobacco overexpressing GhDREB1 showed significant chilling tolerance compared wild-type plants

Summary

Introduction

An external factor incurring negative influence on the plant can be defined as stress Levitt (1972). The major stresses that affect plant growth are water deficiency, chilling and freezing, heat and salinity stress. Among the various abiotic stress conditions, water deficiency is the most devastating factor (Araus et al, 2002). Drought is severely affecting grain production and quality, and situation is becoming more serious with increasing global climate change (HongBo et al, 2006). It negatively impacts on growth and production of crops worldwide, induces a range of physiological and biochemical responses in plants

Plants are constantly exposed to stress

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Transgenic tobacco lines transformed with TPSI showed improved drought tolerance

Transcription Factors Transcription factors are the proteins that bind

Findings

Conclusion and Prospects