Utilization of Dry Land Using Molybdenum, Lime, and Rhizobium Strains to Increase Soybean Yield

Ultisol is a type of soil with low organic matter, pH, and nutrient content, including molybdenum, leading to low productivity. This study aimed to investigate the use of dry land using molybdenum and lime (CaCO3) inoculated with Rhizobium strain Nod+Fix+ to increase the soybean production of Willis and Baluran cultivars. This research was conducted from May to September 2021 in Pallangga Subdistrict, Gowa Regency, South Sulawesi, Indonesia. The study used a split-plot design with three replications for each treatment. The first factor was soybean varieties, consisting of Baluran and Willis cultivars. The second factor was the composition of the bacterial strain Nod+ Fix+, lime CaCO3 and NH4-molybdate, which consisted of without (Rhizobium strain Nod+ Fix+ + CaCO3 + NH4-molybdate); Rhizobium strain Nod+ Fix+ + CaCO3 1.0 ton/ha + NH4-molybdate 250 g/h); Rhizobium strain Nod+ Fix+ + CaCO3 1.5 tons/ha + NH4-molybdate 500 g/h); and Rhizobium strain Nod+ Fix+ + CaCO3 2.0 tons/ha+ NH4-molybdate 750 g/h). The results showed that treating the bacterial strain Nod+ Fix+ + MoCo (1.0:0.6) kg/ha achieved the best results on growth, nutrient uptake (Nitrogen, Phosphorus and Potassium), and soybean yields, both for Willis and Baluran varieties on ultisol soils.