Key word : Biosulpho fertilizer, horticulture, S-oxidizing, P-solubilizing fungi
Sudadi; Sumarno*)
LPPM UNS, Penelitian, DP2M, Hibah Kompetitif Penelitian Sesuai Prioritas Nasional, 2009
This research aimed to develop Biosulpho fertilizer for horticulture commodities. This fertilizer means as slow release fertilizer that supplies P and S for plant continuously along plant growth phase. There were two step research, i.e. 1) first step, aimed to evaluate the affectivity of Biosulpho fertilizer pellet in supplying P and S nutrients for maximum growth and plant yield at greenhouse experiment, and 2) second step, aimed to evaluate the affectivity of Biosulpho fertilizer pellet in supplying P and S nutrients for maximum growth and plant yield at field experiment. The first step conducted at Lab. for field experiment of Fac. of Agric., UNS at Jumantono district and second step will conducted in field at Sragen and Sukoharjo district. Experiment used three soil type, phosphate rock content and inoculums composition of biosulpho fertilizer with onion and soybean as plant indicator. All experiments arranged in completely randomized design and replicated three times at each of combination treatment. Variables observed were soil available-P, available-S, pH, and plant yield. Data analyzed by F test at 95% of level significant followed by DMRT if there were any significant differences. The result show that the treatment combinations with highest available-P and S were different in liquid and solid medium as well as in biosulfo pellet. A. niger : P.nalgiovensis with 3 :1 and 1 : 1 proportion were the best treatment combinations in liquid and solid medium respectively, while (80 – 20, 1 : 1), (80 – 20, 3 : 1) and (60 – 20, 3 : 1) treatment combinations have a high av-P and av-S in biosulfo fertilizer pellet. Biosulfo formula of BF60 J11 and organic matter and biosulfo fertilizer dosages of BO10 BIO450 gave the highest soybean yield at Alfisol, BF60 J31 and BO5 BIO450 at Entisol and BF60 J11 and BO5 BIO450 at Vertisol.respectively. While formulas of BF60 J11 and BO10 BIO450 gave the highest of onions yield at Alfisol, BF60 J11 and BO5 BIO900 at Entisol and BF60 J11 and BO10 BIO450 at Vertisol. Biosulfo needed to improve these biosulfo formulas effectivity especially for specific location and commodities.