Effects of Phosphorus-Mediated Alleviation of Salt Stress on Cotton Genotypes: Biochemical Responses and Growth Adaptations

Abstract

Salinity stress can significantly impact productivity in agricultural area with limited water re-sources. Our study focused on how plants under salt stress respond to phosphorus availability in terms of growth and biochemical reactions in cotton genotypes. Two cotton genotypes with different P efficiencies (SK39 and JM21) were used in a hydroponic experiment with 300 mM NaCl and three P treatments (10, 20, and 30 mM). Salinity stress decreases root growth, shoot growth, biomass production, and chlorophyll content, according to the experimental findings. In treated plants, it also increased the levels of oxidative stress. However, this effect was alleviated by phosphorus therapy, which controlled the production of proline, total soluble sugars, and hydrogen peroxide (H2O2). Interestingly, salt-sensitive JM21 responded to phosphorus supplementation more favorably than salt-tolerant SK39. Our research emphasizes the critical role that phosphorus especially P20 plays increasing the salinity stress sensitivity of cotton plants and offers insightful in-formation on the mechanisms underlying the role of phosphorus in reducing salinity stress effects. This study also revealed interspecific variability in cotton genotypes and characteristics, primarily represented by attributes related to cotton growth and morphological indicators such as dry matter biomass.