Evaluating growth stimulants for improving different morpho-physiological and seed quality parameters in American cotton

Cotton is a crucial fiber and oilseed crop, significantly contributing to the global textile industry and agricultural economy. Enhancing cotton yield and seed development through agronomic interventions, such as the application of growth stimulants, has gained importance in optimizing productivity under varying environmental conditions. In this experimental study, effects of different growth stimulants-spermidine, potassium nitrate (KNO3), bavistin and a combination of KNO3 + bavistin were evaluated on key physiological traits, yield components, and seedling quality traits of American cotton variety H 1098i. The experiment was conducted during the Kharif 2018 in randomized block design with three replications. Treatments were applied at 90 and 120 days after sowing and key morpho-physiological and seed quality traits were measured. Our results revealed that KNO3 treatments significantly improved chlorophyll content and seedling dry weight, while spermidine-treated plants showed enhanced photosynthetic rate and stomatal conductance. Additionally, KNO3 and its combination with Bavistin significantly increased the number of bolls per plant, with the highest boll production observed in KNO3-treated plants. Yield traits such as biomass, seed weight, and lint weight were also positively affected by spermidine, with the highest seed weight. Furthermore, seedling quality traits, including seedling vigour and dry weight, were significantly improved by KNO3 treatments, highlighting its role in enhancing early plant growth. This study underscores the potential of growth stimulants, particularly KNO3 and spermidine, in improving physiological efficiency, seed development and yield in American cotton.