Improved black soybean performances grown on selected highly weathered soils by using bio-nano-ortho silicic acid

The objectives of the study were to determine the potential use of bio-nano-ortho silicic acid (OSA) originated from locally mineral enriched with silica-solubilizing microbes to improve yield, reduce chemical fertilizer dosage, and increase water use efficiency (WUE) of black soybean grown on selected highly weathered soils. The first-year (2017) study was conducted at Majalengka and Natar area and arranged in a random block design (RBD) with three replicates, using a Detam-1 variety. Treatments of NPK fertilizers were 0, 50, 75, and 100% of standard recommended dosages in combination with 0, 2, 4, and 6 L bio-nano OSA Ha−1. In general, application of 4 L bio-nano OSA Ha−1 saved 32% NPK fertilizer dosage and improved growth and yield of Detam-1. The second year (2018) trials consisted of no fertilization (P0), farmer standard NPK fertilization (P1), P1 + organic matter (P2), 4 L bio-nano OSA Ha−1 + NPK (P1), 50% (P3); and 75% (P4) respectively, arranged in a RBD with three replicates at three regions, i.e. Majalengka (Alfisols), Natar (Ultisols), and Indramayu (Alfisols). The results confirmed that the application of bio-nano OSA at 4 L Ha−1 improved nutrient use and WUE as well as yield of Detam-1 on all three soils studied.