Selenium Concentration in Fodder Crops as Affected by the Application of Gypsum and Phosphate Fertilizer

Field experiments were conducted to study the effect of gypsum and phosphate fertilizer on selenium concentration in berseem (Trifolium alexandrinum) and sorghum (Sorghum bicolor) crops in the seleniferous region of Punjab. Sulphur was applied through gypsum at 0, 4, 8 and 12 q ha–1 and phosphorus at 0, 60, 90 and 120 kg P2O5 ha–1 through di-ammonium phosphate. Selenium concentration in berseem and sorghum decreased significantly with the application of 8 and 12 q gypsum ha–1. In different cuts of berseem, the decrease in Se concentration varied from 39% to 49% with the application of 12 q gypsum ha–1. The effectiveness of gypsum decreased, as the growth of berseem advanced towards maturity. No consistent changes in Se concentration of fodder crops were observed with the application of phosphate fertilizer. The results suggest that gypsum application to seleniferous soils may be an economically viable option for reducing Se accumulation by forage crops. However, there is a need to further verify the role of P in regulating Se uptake by different crops