Chitosan Induced Modification in Morpho-Physiological, Biochemical and Yield Attributes of Pea (Pisum Sativum L.) Under Salt Stress

Salinity is one of the most significant abiotic stresses that limit the growth and yield of plants. It is estimated that salinity has destroyed about two-thirds of the world's agricultural land. So the present study was designed to appraise the chitosan (CS) induced amendments in morpho-physiological, biochemical and yield attributes of two pea (Pisum sativum L.) varieties under different levels of salt (NaCl) stress. The seeds of two pea (Pisum sativum L.) varieties (Meteor and Polo) were treated with two salt levels (50mM and 100mM) and two concentrations of CS (50 mgL(- 1)and 100 mgL(- 1)) separately and in combination after 30 days of germination. Salt stress was applied as irrigation water to the soil and CS solutions were applied exogenously by foliar treatment. Salt stress significantly reduced the growth and photosynthetic pigments as compared to control plants, while foliar application of CS showed an improvement in these attributes. Higher concentrations of salt affected the growth and development of pea plants more adversely as compared to its lower concentrations. While CS decreased electrolyte leakage, uptake of Na+, and proline accumulation but further increased antioxidant activity in plants under salt stress, salt stress also increased electrolyte leakage and Na+ accumulation in plant leaves, which led to proline accumulation and higher antioxidant (SOD, POD, and CAT) activity in stressed plants. The yield attributes were also adversely affected by salt stress as it reduced the number of pods per plant, number of seeds per pod, number of seeds per plant, and 100 seed weight while CS along with 100 mM salt stress improved the number of pods per plant (116.6%), number of seeds per pod (54.64%), number of seeds per plant (57.4%), and 100 seed weight (77.3%) as compared to plants under salt stress (100 mM NaCl). Conclusively, CS (50mgL(- 1)) ameliorated the adverse effects of salt stress to a significant extent and improved the overall yield of pea plant. Furthermore, comparison of both pea varieties showed that polo proved to be more tolerant to salt stress.