Intercropping Sorghum (Sorghum bicolor L.) and Cowpea (Vigna unguiculata L.): Effect of Bradyrhizobium Inoculation and Fertilization on Minerals Composition of Sorghum Seeds

This investigation was carried out in order to gain a better understanding of the effect of Bradyrhizobium inoculation and fertilization on the nutritional values of macro- and micronutrients of sorghum intercropped with cowpea in the field under rainfed conditions. The results of the present study demonstrated that intercropping, Bradyrhizobium inoculation, and N and P fertilization had significant effect on the mineral status of sorghum seeds. Intercropping significantly (𝑃≤0.05) increased Ca, Mg, Cu, Mn, and Fe contents of sorghum seeds, while it had no effect on the concentration of P, K, Na, and Zn in the sorghum seeds. However, Bradyrhizobium inoculation did not enhanced the most of minerals content of sorghum in both cropping systems; it slightly reduced the phosphorous content of sorghum seeds in the two cropping systems. Results of application of N and P fertilizers separately or combined with Bradyrhizobium showed fluctuated effect on the mineral contents in both cropping systems and both seasons.