2012 Volume 58 Issue 1 Pages 9-15
Differences in nutrient concentrations and nutrient uptakes among sorghum varieties were evaluated. Sorghum was cultivated in 2005 and 2006, and 65 varieties were evaluated in both years. Variety differences were observed in the N, P_2O_5, K_2O, CaO, MgO, and NO_3-N concentrations and K/(Ca+Mg) equivalent ratio. Variety differences were also observed in the N, P_2O_5, K_2O, CaO, and MgO uptakes. When sorghums were divided into grain type, dual-purpose type, sorgo type, and Sudan type sorghum, and Sudan grass varieties, the means of both the nutrient concentration and uptake were higher in Sudan type sorghum and Sudan grass varieties than in grain type, dual-purpose type, and sorgo type varieties. The NO_3-N concentration exceeded 0.2% in no grain type, dual-purpose type, or sorgo type sorghum varieties but in 28 of 32 Sudan type sorghum and Sudan grass breeds. The K/(Ca+Mg) equivalent ratio exceeded 2.2 in 6 of 32 grain type, dual-purpose type, and sorgo type sorghum varieties and 26 of 32 Sudan type sorghum and Sudan grass varieties. The NO_3-N concentration was 0.2% or lower, and the K/(Ca+Mg) equivalent ratio was 2.2 or lower, in "Tozanko 32", "T122", and "HSK1" among the Sudan type sorghum and Sudan grass varieties. The nutrient concentrations and uptakes were high in "SS701", "Roleking", and "PC3079", which are Sudan-type sorghum and Sudan grasses.
