Optimization of Sorghum Cultivation (Sorghum Bicholor) with Ameliorant Addition in the Post-Tin Mining Of Bangka, Indonesia

˗˗˗Sorghum is a drought-tolerance plant that have ability to survive on post-tin mining land. One way to increase the optimum growth and production of sorghum on post-tin mining land can be done by ameliorant addition. The objective of the study was to increase the optimum growth and production of sorghum in post-tin mining land. The experiment had been conducted in post-tin mining area located in Dwi Makmur Village, Merawang, Bangka, from November 2017 May 2018. The experiment was conducted using Completely Randomized Design (RAL) with 1 (one) single factor as follows: Control (C0), NPK (C1), 40 gram phosphate solubilizing fungi (C2), SP36 100 kg ha -1 (C3), SP36 200 kg ha -1 (C4). The results showed that the application of 40 grams phosphate solubilizingfungi (C2) had the highest value on the dissolved solid total (° Brix). Complete NPK fertilizer (C1) has the highest root growth when its compared to other treatments. This indicates that full NPK fertilizer (C1) are able to increase the production of seeds/plant and harvest index (%). The addition of ameliorant is able to increase the optimum growth and production of sorghum in post-tin mining land of Bangka. Keyword˗˗˗Sorghum, ameliorant, post-tin mining, phosphate solvent microorganism