Published Paper Details:

Climate change is a multifaceted phenomenon with a wide range of impacts on the environment. Currently, with the competing uses of land and the growing world population, we are challenged to produce more in less area with diminishing resources, confronted with climate change and the unpredictable local microclimate adversely affecting crop productivity. Abiotic stresses will remain a challenge to the natural environment and agriculture. The challenges before us in plant biology and crop improvement are to integrate the systems level information on abiotic stress response pathways, identify stress protective networks, and engineer environmentally stable crops that yield more. In the present study, two different antioxidant enzymes namely copper-zinc superoxide dismutase derived from Potentilla astrisanguinea (SOD) and ascorbate peroxidase (APX) from Rheum austral both of which are high altitude cold niche area plants of Western Himalaya were cloned and simultaneously over-expressed in Arabidopsis thaliana to alleviate PEG stress. It was found that the transgenic plants over-expressing both the genes were more tolerant to PEG-induced stress during growth and development. In both transgenic plants higher levels of total antioxidant enzyme activities, chlorophyll content, total soluble sugars, proline content and lower levels of ROS, ion leakage were recorded when compared to the wild type (WT) during PEG stress. The transgenics in the present study showed 2-3 fold increase in SOD and APX activity resulting in the enhanced stress tolerance to PEG stress than WT. In terms of growth and development in number of leaves, rosette area and root length, which was observed to be significantly higher in transgenic lines compared to WT. Also, the transgenic lines showed higher germination percentage at various levels of PEG. Overall, SOD and APX transgenic lines were able to express greater drought tolerance and thus the present work would pave way for the judicious use of these genes effectively into the relevant crop plants leading to optimum growth and enhanced yield under environmentally stressed conditions.