Physiological response of soybean (Glycine max L.) with various compositions of urea and palm sugar stem bagasse with decomposer and biochar

Abstract The excessive inorganic fertilizers detain Indonesian soybean yield improvement as it results in a decrease in soil fertility. The addition of organic fertilizers can recover soil fertility. This study investigated the organic fertilizers with different compositions of urea and palm sugar stem bagasse (PSSB) for their effect on soybeans’ physiological response and yield. Moreover, adding decomposer and biochar to the organic fertilizer was also evaluated. The research employed an experimental approach with a completely randomized design. All measurements were conducted in triplicates. The study found a correlation between the composition of urea and PSSB with decomposition treatment towards stomata density after six weeks of planting. Soybeans with higher stomata density were seen in soybean plants that applied 75% PSSB + 25% urea and decomposer, as well as urea-only fertilizers without decomposers. No significant difference was shown in different urea and PSSB compositions towards other physiological responses of soybeans. Biochar addition to soybean plants can increase stomata density after three weeks of planting and its relative growth rate.