gypsum and bio-fertilizers altered grain yield, forage, and nutrient elements of sorghum (sorghum bicolor l.) in a saline soil

Objective: soil salinity significantly affects the growth and crop productivity. application of chemical amendments, such as (gp) (caso4.2h2o), has been shown to improve saline-sodic soils, thereby promoting better plant growth and development. this study aimed to evaluate the effects of three levels of gp and different types of bio-fertilizers on grain yield, yield components, forage quality, and concentration of nutrient elements on sorghum in a saline soil.methods: this study was laid out as a split plot design based on the randomized complete block with three replications on sorghum at a saline soil (ec = 5.9 ds/m). three levels of gp, including 0 (control), 10, and 20 t/ha, were arranged in the main plots, and five types of bio-fertilizers, including biosulfur, phosphosist, nitroxin, phosphate bio-fertilizer (barvar 2), and the control (without application of bio-fertilizer), were arranged in subplots.results: the results showed that the application of gp increased grain yield and yield components. the highest grain yield, number of seeds per plant, and 1000-seed weight were obtained with phosphosist + 20 t/ha of gp. these increases were 58.8%, 37.3%, and 34.4%, respectively, as compared to the control treatment (no bio-fertilizer and no gp). additionally, gp improved forage quality by increasing the neutral detergent fiber (ndf) in some cases. the highest ndf was obtained at the 20 t/ha gp. the interaction between gp and bio-fertilizers significantly affected the concentration of n, p, fe, and cu in the leaves of sorghum; however, the concentration of ca, k, mn, and zn was not affected by this interaction. nutrient concentration generally increased until the highest application of gp in the soil. the highest concentration of n, fe, and cu was obtained for the biosulfur at the rate of 20t/ha gp and of p at the phosphosist + 20t/ha gp.conclusion: the combined application of gp and phosphosist (as a bio-fertilizer) had the most pronounced positive effect on both grain yield and forage quality in sorghum at a saline soil.