Soybean Response to Mycorrhiza, Rhizobium, P-Solubilizing Bacteria and Lime Application in Ultisol Soil

Availability of phosphorus (P) and nitrogen (N) in acid soils are generally low because P is transformed into the form of P that are not available to plants, while low of N can be caused by the slow process of organic N mineralization in acidic conditions. The study was aimed to assess the effect of lime and synergistic effect between biofertilizers mikorhiza, rhizobium, and P-solubilizing bacteria on soybean grown in Ultisol soil. The experiment was conducted under greenhouse conditions with a split plot design and six replications. The main plot was the equivalent dose of lime: 0 and 800 kg dolomite / ha. The sub plot was biofertilizer: 1) without biofertilizer, 2) mycorrhiza (VAM), 3) P-solubilizing bacteria (PSB), 4) Rhizobium, 5) VAM + PSB, 6) VAM + rhizobium, 7) PSB + rhizobium, and 8) VAM + PSB + rhizobium. The result showed a synergistic effect of Rhizobium, PSB and VAM in increasing growth, root nodules dry weight, N and P uptake, grain yield and yield components of soybean. The highest increased in grain yield (102%) over control (without biofertilizer and lime) was obtained from the combination of the three biofertilizers + lime application.