Effect of Intercropping, Bradyrhizobium Inoculation, Nitrogen and Phosphorus on Growth, Yield and Seed Quality of Cowpea and Sorghum under Rainfed Conditions

Abstract

A field experiment was carried out, at the experimental farm of the University of Sennar, Abu Naama Sennar State,, for two successive seasons, to study the effect of intercropping, Bradyrhizobium, nitrogen and phosphorus on the growth, yield and seed quality of cowpea and sorghum under rainfed conditions. The results showed that intercropping significantly increased the nitrogen, phosphorus content of the shoots cowpea and sorghum, as well as the protein content, the in vitro protein digestibility and the fiber content of seeds. Bradyrhizobium, nitrogen and phosphorus significantly increased the nodules number, nodules dry weight, dry matter content, plant height, nitrogen and phosphorus contents and yield of cowpea. Nitrogen and phosphorus significantly increased number of leaves, leaf area, plant height, shoot dry weight and yield of sorghum. Moreover, Bradyrhizobium significantly increased moisture, ash, fiber, protein and tannin content as well as in vitro protein digestibility of cowpea and sorghum seeds and significantly decreased the carbohydrates content. Furthermore, nitrogen and phosphorus significantly improved the hydration coefficient, moisture, ash, fiber, fat and protein content and significantly decreased the carbohydrates of cowpea and sorghum. All the values of the land equivalent ratio (LER) were more than one, which indicates the efficiency of the intercropping system in utilizing resources in comparison to the sole cropping of the component crops. In conclusion, intercropping, Bradyrhizobium inoculation and chemical fertilizers seems to improve the growth, yield and seed quality of both crops. However, more research is needed in intercropping, biological and chemical fertilizers in rainfed areas.