Benzyl Amino Purine (BAP), Moringa Leaf Extract and Ascorbic Acid Induced Drought Stress Tolerance in Pea (Pisum sativum L.)

Drought stress is the most detrimental factor among the abiotic stresses that globally affected the legumes crop productivity and cause of economic loss and threatened food security. The pot experiment was designed to study the role of ascorbic acid (AsA), benzyl amino purine (BAP) and moringa leaf extract (MLE) for induction of drought stress tolerance on two pea cultivars (Mateo rans Pea-09). Both pea cultivars were subjected to drought stress (60% field capacity) after 20 days of germination while controlled plants were maintained at 100% field capacity. Treatments of BAP (0.005%), AsA (0.005%) and MLE (30%) were applied as foliar spray after two weeks of imposed water stress. When plants undergo water stress regimes, growth, chlorophyll and yield attributes decreased significantly as compared to control. While antioxidant enzymes peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD), osmolytes such as proline and glycine betaine (GB) increased to respond water stress. Foliar application of BAP, AsA and MLE under water-scarce situations up-regulated the enzymatic antioxidants and enhanced growth and yield attributes under water stress. The total soluble proteins and nitrate reductase (NR) decreased while total free amino acids, proline and soluble sugars increased under water deficit situations. Foliar application of these substances also decreased the over expressed malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents under water deficit regimes. The foliar spray of these growth regulators increased growth and yield by increasing photosynthetic pigments, up-regulating the enzymatic antioxidants and osmolytes under water stressed and non-stressed conditions.