Effect of application of organic amendments on quality of forage sorghum (Sorghum bicolor L.) in the semi-arid tropics

Abstract

Annual forage sorghum (Sorghum bicolor L.) is an important fodder for animals in Sudan. A two-year field experiment was conducted at the Experimental Research Farm of the Faculty of Agriculture, University of Khartoum, Sudan, to characterise the quality dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and digestibility of CP and NDF and mineral composition (TN, P, K, Ca, Mg, Na, Zn, Fe, Mn, Cu and Mo) of forage Sorghum after incorporation of organic amendments. Treatments were 87.6 kg N ha71 in form of urea, 3073 kg chicken manure ha71, 11,680 kg farmyard manure ha71 and a combination of farmyard manure and chicken manure at a rate of 7376 kg ha71 and a control and were arranged in a randomised complete block design with four replications. Results showed that organic amendments significantly produced similar forage DM yield and CP content as inorganic fertilizer. Also, amendments significantly decreased and increased NDF contents and their respective digestibilities. Similarly, contents of N, P, K, Mg, Ca, S and trace elements were significantly higher with the application of organic fertilizers. This study generally concluded that in both seasons, incorporation of organic amendments improved mineral content of forage sorghum compared to inorganic fertilizers and with almost similar digestibility.