Role of organic amendments in improving physiological and yield parameters of okra grown under saline conditions

Purpose: Salinity is a devastating abiotic stress that poses serious risks to agricultural sustainability and global food security. The yield of okra [Abelmoschus esculentus (L.) Moench] is adversely affected by salinity stress. The research was conducted to evaluate the effects of organic amendments on the physiological and yield parameters of okra plants under saline conditions. Method: In a pot experiment, okra plants were grown in non-saline and saline (50 mM sodium chloride) soil supplemented with municipal solid waste compost, farmyard manure (FYM), and press mud, each applied individually or in various combinations (Compost + FYM, FYM + Press mud and Compost + Press mud). Results: Salinity stress significantly reduced relative water content, membrane stability index, chlorophyll and carotenoid contents, photosynthetic rate, fruit length, fruit diameter, no. of fruits per plant, fruit fresh weight, fruit dry weight, fruit yield per plant, no. of seeds per pod and 100 seeds weight of okra plants, compared to control. Under saline conditions, 5% (FYM + Press mud) was the most effective treatment in significantly improving stomatal conductance, intercellular carbon dioxide concentration, no. of fruits per plant, fruit dry weight, and fruit yield per plant of okra, compared to saline soil. Conclusion: Application of 5% (FYM + Press mud) could improve the physiological and yield parameters of okra grown in saline soil (50 mM Sodium chloride) by mitigating adverse effects of salinity and could be used as a cost-effective and bio-rationale approach for alleviation of salinity stress in crops to attain agricultural sustainability.  Research Highlights • Salinity adversely affected the physiological parameters and yield of okra plants. • Under saline conditions, 5% (Farmyard manure + Press mud) was the most effective organic amendment in significantly improving stomatal conductance, intercellular carbon dioxide concentration, no. of fruits per plant, fruit dry weight, and fruit yield per plant, compared to saline soil. • The application of 5% (Farmyard manure + Press mud) could be used as an economic and feasible strategy to improve the physiological and yield parameters of okra grown in saline soil (50 mM Sodium chloride) by ameliorating adverse effects of salinity.