Role of Microbial Inoculants in Enhancing Soil Fertility and Crop Productivity in Organic Farming Systems

Organic farming, currently practiced in 188 nations and across 96.4 million hectares of land, focuses on biodiversity, ecological integrity, and sustainability. They play roles in nutrient cycling, decomposition of organic matter, antagonism, competition and mutualism with plants, which are fundamental for sustainable agriculture. The study aims to evaluate the effect of microbial inoculants on the fertility of organic soil and green tea production in organic farming systems, especially with multi-strain agents. In the current study, field trials were carried out on certified organic farms in Thai Nguyen Province, Vietnam, where an RBD was used to implement control, single-strain, multi-strain, and commercial inoculant treatments. Physicochemical characteristics of soil, including pH, organic carbon, available nutrient content, microbial biomass, germination index, plant height, leaf biomass, Yield, and antioxidant status of the plants, were measured and recorded. Results showed that multi-strain inoculants significantly improved soil fertility (organic C: 1.8%, microbial biomass 520 µg/g, n = 41 mg/kg), green tea yield 3900 kg/ha, and leaf antioxidant 15.2%. It was found that microbial biomass has a very high positive relationship with Yield, with an R² value of 0.91 for the regression coefficient. In conclusion, it is evident that microbial inoculants made from multiple strains improved soil health, green tea production, and product quality, and microbial inoculants can be used to support successful available systems of organic farming in various climates.