Agro-biofortification of maize with selenium for higher grain selenium contents and productivity

Selenium (Se) is a vital mineral nutrient for animal and human health, which can be supplemented through seed biofortification techniques. Present study determined the potential of improving Se content in maize grain via several Se fertilizer application methods to enhance the nutritional status of native populations. Field trials were conducted for two growing years with different Se application methods and application rates to evaluate grain Se content in maize, Se recovery, grain macro- and micro-nutrients and grain yield under rain-fed conditions. Results demonstrated that foliar and soil Se applications showed no significant impacts on maize biomass and grain yield as well as maize grain N, P, K, Ca, Mg, Fe, Mn, Cu and Zn contents. However, both foliar and soil Se application significantly enhanced the maize grain Se content. Foliar application of Se exhibited greater Se recoveries of 54 % and 108 % in the grain over soil Se fertilizer for the first and second growing seasons while the later was recorded with only 1.71 % and 0.97 % increase as compared to control. In conclusion, foliar Se application at silking stage at the rate of 8.85 µM enhanced the grain Se content in maize at minimum costs as compared to soil Se application.