Selenium nutrition for yield enhancement and grain biofortification of wheat through different application methods

Selenium (Se) is an essential nutrient for humans and it enters in the food chain by plant uptake from the agricultural soils. However, about 15% of world's population is Se deficient due to its deficiencies in soil causing deficiency in human nutrition. This study was carried out to evaluate the influence of Se supplementation through various methods on two bread wheat cultivars (Shafaq-2006 and Lasani-2008) under field conditions. Selenium was applied through seed priming (0.125 and 1.25 mM Se solution), seed coating (0.5 and 1.0 g Se kg^-1 seed), foliar spray (50 and 100 g Se ha^-1) and soil application (50 and 100 g Se ha^-1) using Na2SeO4 as source. Results show that Se application by either method significantly improved the growth, grain yield and grain Se concentration compared to no Se application. Among the application methods, soil fertilization at 100 g ha^-1 and foliar spray at 50 g ha^-1 displayed greater leaf area index, crop growth rate, grains per spike, thousand grain weight, biological yield, grain yield and harvest index. Performance of cultivar Lasani-2008 remained better than Shafaq-2006 in both quantitative and qualitative terms. Maximum grain Se enrichment was recorded in Lasani-2008 with foliar spray of 100 g Se ha^-1. Seed priming with 0.126 mM Se solution proved more economical and showed highest net return (Rs. 73176) followed by foliar spray at 50 g ha^-1 (Rs 71385). Present study suggests that Se application by either method could improve growth, yield and grain Se concentration in bread wheat.