ABSTRACT
Abiotic stresses such as drought, salinity, heat and cold, are greatly affecting the plant growth and agricultural productivity and causes more than 50% of worldwide yield loss of major crops every year. Many efforts have been made by researchers to mitigate these stresses and to increase crop productivity under unfavourable environments. Traditional measures are niche-specific and exhibit tremendous vulnerability to the climactic conditions due to varied intensity of edaphic factors. Genetic engineering is one of the tools being used to develop crop plants which are tolerant to these stresses. It is imperative to understand the adaptive mechanism of plants to drought especially the type and expression levels of drought responsive genes. Several genes upregulated during abiotic stress have been exploited to develop drought tolerant plants. Genetic engineering of crop plants with stress responsive genes has been an effective method of generating drought tolerant plants. Keeping this in purview, the present chapter makes a serious attempt to accumulate the available information and finally come out with a sound strategy by deploying cutting edge science and modern biotechnological approaches paying special attention towards development of large scale cultivation of transgenic crops, which is deemed to be conclusive by halting menaces caused by biotic and abiotic stresses to enhance productivity especially at the interface of global climatic changes, which are amplifying alarmingly, which would lead to acute food and nutritional insecurity which would fail to sustain an livelihood.
