Improving inorganic nitrogen in soil and nutrient density of edamame bean in three consecutive summers by utilizing a locally sourced bio-inocula

Abstract

Soil microbial communities are key players in the development of sustainable food production systems. These soil microbes are responsible for macronutrient and micronutrient mineralization and solubilization in soil. Local effective microorganisms (LEM) are a locally sourced bio-inoculate, made from a fermented mixture of actively decomposing forest litter and a nutrient rich growing media containing carbohydrate, milk, and water. It can be made on farm and have a suite of bacterial communities that includes phototrophic bacteria, phosphorous-solubilizers, ammonia-oxidizers, nitrogen fixers, and actinomycetes. The goal of our research was to (a) investigate microbial diversity in LEM and F-LEM bio-inocula; (b) identify bacterial and archaeal communities in soil after bio-inoculation with LEM, F-LEM, or Control; (c) assess inorganic nitrogen in the soil; and (d) evaluate Ca, Mg, K, and Zn nutrient density in edamame bean (Glycine max) grown with composted broiler litter inoculated with LEM, F-LEM, or Water (Control). Treatments were arranged in a completely randomized block design with four replications on twelve, 18 m2 organically managed plots. Results of microbial characterization indicated greater biodiversity of functional groups in the LEM inoculum. Inorganic N was significantly greater in LEM plots compared to Control in second (2016) and third (2017) years of the study. Biofortification of calcium, magnesium, and zinc density of LEM grown edamame was significantly greater compared to both Control and False-LEM grown edamame (*P < 0.05).