Effect of Potassium Sulfate Fertilizer on the Mineral Profile of Sorghum Forage and Their Uses as Ruminant Feed

Abstract

This study aimed to determine the effect of Potassium sulfate fertilization on the mineral profile of sorghum forage. A field trial was conducted at University of Khartoum Experimental farm at Shambat. The treatment consisted of six levels of Potassium sulfate fertilizer 0, 10, 20, 30, 40, and 50 kg/Acre. The data were subjected to analysis of variance (ANOVA) with a complete randomized design using SPSS software program. The evaluation was done by determining the percentage of Ash, NO3, macro minerals (N, P, K, Ca, Na and Mg), and micro minerals (Cu, Mn, and Zn). The results showed that the application of potassium sulfate fertilizer increased significantly (P<0.01) the nitrogen content of the sorghum forage from 1.4 % in the control to 2.14 % in the 50 kg/Acre potassium sulfate fertilizer, while the effect on NO3 was found to be insignificant. The potassium content of forage sorghum increased significantly (P<0.01) with the increase in potassium sulfate fertilization level and the highest value (0.77) was recorded in 50 kg/Acre level of fertilization. The Mg content decreased with an increase in fertilization level and the control recorded the highest value (0.44 %). The effect of potassium sulfate fertilization on Cu, Mn, and Zn was found to be significant (P<0.01). The potassium concentration of sorghum forage is significantly (P<0.05) and positively correlated with nitrogen (γ=0.67) and negatively correlated with phosphorous and magnesium (γ= - 0.65) and (γ= - 0.59), while non-significant correlation was observed between potassium and Ash, NO3, Ca, Na, Cu, and Mn.  It could be concluded that the quality of forage sorghum increased by potassium sulfate fertilization because the nitrogen and potassium content in the plant increased and the concentration of NO3 decreased.