The efficacy of biofertilizer contains Bradyrhizobium japonicum isolates on soybean yields grown in Inceptisols, Bogor, West Java, Indonesia

Abstract

The use of biofertilizers is growing rapidly and promising for food crops and horticulture. They are capable to improve soil fertility, increase crop growth and yield, and environment friendly. Soybean is a strategic commodity in Indonesia. Various ways of cultural practice to improve soybean yield have been reported. The biofertilizer containing six Bradyrhizobium japonicum isolates with husk charcoal powder carrier material has been tested on soybean in Cibungbulang Bogor. Our objective was to evaluate the efficacy of Bradyrhizobium japonicum biofertilizer on soybean growth and the yield on Inceptisols Cibungbulang Bogor. The experiment was a randomized block design consisted of seven treatments with four replications. The treatments were (1) Control, no fertilizer (2) 100% NPK (3) Biofertilizer, (4) Biofertilizer + 25%NPK, (5) Biofertilizer + 50% NPK, (6) Biofertilizer + 75% NPK and (7) Biofertilizer + 100% NPK. The results showed that the promising treatment to improve soybean yield was Biofertilizer + 50% NPK and Biofertilizer + 75% NPK as indicated by significantly increase of soybean yield from 18.56 to 25.77% compared to the treatments of 100% NPK, reduced NPK fertilizer 25 to 50%. The values of Relative Agronomic Effectiveness were 191% and 165%. This study implies that the application of biofertilizer gave a positive result both on the growth and yield of soybean.