International Journal of Plant & Soil Science

Based on the first research, Streptomyces narbonensis and Trichoderma harzianum mixed was a Biological Agents (BCAs) of tomato fusarium wilting. Another research found Streptomyces sp. and Trichoderma sp can be decomposers and growth hormone producers. This study examined S. narbonensis and T. harzianum as decomposers and Plant Growth Promoting Microorganisms for horticulture crops in various types of soils. Microorganism suspension was applied with a combination of S. narbonensis sp. and T. harzianum with different compositions (1:1; 2:1; 3:1 and 4:1) in liquid Glucose Potato Extract media, then microorganisms mixed was applied into three soil types Vertisol, Regosol, and Andisol. Each treatment was repeated three times. The growth of vegetative plants, the number of microorganisms, and physical-chemical soil were analysed 30 days after planting. The results of the soil conditions after the addition of the microorganism almost did not affect nutrient levels in the soil, but only affected the available P regosol soil and increased microbial abundance that affects the decomposition of C-organic.