Optimization of culture medium and bioformulation of rhizobial actinomycetes to enhance soybean plant growth

Abstract. Fatmawati U, Qurrata’aini MR, Rosyidi NW, Sari DP, Santosa S. 2023. Optimization of culture medium and bioformulation rhizobial actinomycetes to enhance soybean plant growth. Biodiversitas 24: 2912-2918. Actinomycetes are a group Gram-positive bacteria that well-known for having growth-promoting activity. In an earlier study, Streptomyces sp. strain ASR 58 67, isolated from rhizosphere, were found be capable producing Indole-Acetic Acid (IAA), dissolving phosphate, stimulating media selection carrier materials formulation necessary maintain actinomycetes' cell viability growth property stability. This study aimed evaluate several media, determine the optimal in formulation, effect actinomycete on planta. The sugar potato broth was best increasing biomass 67 co-culture compared other mediums (skim molasses rice bran broth). (5.3 x 107 CFU/mL), (3.8 its combination both (4.3 CFU/mL) maintained talc powder during 10 weeks storage as revealed by number viable cells decreases. Applying formula enhanced four after planting, including height, leaves, root dry weight.