CAMTA transcription factor enhances salinity and drought tolerance in chickpea (Cicer arietinum L.)

Various abiotic stresses like drought, salinity, high temperature, and chilling adversely affect plant growth and productivity. Terminal drought stress is one of the major concerns which limits the growth and yield of chickpeas. Calmodulin binding transcription activator (CAMTA) plays a vital role in stress tolerance in plants. In this study, the role of the CAMTA gene was assessed by over-expression in chickpea (Cicer arietinum L.) in response to drought and salinity stress. The over-expressing lines of the CAMTA gene have shown enhanced activities of various antioxidant enzymes (ascorbate peroxidase (APX), catalase (CAT), glutathione S-transferase (GST), superoxide dismutase (SOD), monodehydroascorbate reductase (MDHAR)). The reduced stress markers TBARS and H₂O₂ enhanced the survival of plants against both stresses. The physiological parameters (net photosynthesis; P_N, transpiration; E, stomatal conductance; g_s, photochemical quenching; qP, non-photochemical quenching; qN, and electron transport rate; ETR) were improved in the transgenics under both the stresses that protected the plants from damage. This investigation verified that the CAMTA gene provides tolerance against drought and salinity by maintaining biochemical, physiological, and morphological performances and could be exploited for genetic engineering strategies to overcome the stresses in other economically important crops.