Effect of Se, Zn and Fe application on yield and nutritional quality of maize and soybean

Pot experiments were conducted with maize and soybean as test crops to study the effects of application of Se, Zn, Fe on crop yields and nutritional quality. Obtained results showed that application of N, P, K fertilizers only had insignificant effect on the yield of maize and soybean, but application together with Se, Zn, Fe had increased the grain yield of maize by 15.6%-73.8% and that of soybean by 58.9%-115.1% compared to the control (no fertilizer application). Se, Zn, Fe application could increase N，P contents of maize grain, while no significant effect on its K content. For soybean, Se, Zn, Fe application had no significant effects on grain N content, but decreased P and K contents. Se, Zn, Fe application could significantly increase Se，Zn and Fe contents in maize and soybean grain. Among different Se, Zn, Fe application methods, soil combined with foliar application of Se, Zn, Fe had increased the grain Se, Zn and Fe contents respectively by 480.4%, 106.9% and 126.7% for maize, and 512.9%, 62.2% and 15.6% for soybean compared to the control. By considering both the grain yield and its micronutrient content, both soil application and soil combined with foliar application were feasible for Se and Zn. Foliar application was the effective way to increase grain Fe content of crops.