Low temperature and various environmental stress affects the growth of plant and its development which causes a significant crop losses. Plants respond to such condition by changing their pattern of gene expression and protein products when exposed to low temperature. Because of cold and low temperature many plant species from tropical and sub-tropical region affects from cold injury like chlorosis, necrosis etc. When a plant is exposed to cold climate the water present in the apoplast and intercellular space converts into ice resulting dehydration of the plant further suffers from cold injury. To overcome such conditions certain desired genes were inserted into the plant by rDNA technology and genetic engineering to improve crop productivity and for quality yield. Some genes like COR gene also called as cold responsive gene get activates when exposed to cold or low temperature.