Intensification of vermitechnology for kitchen vegetable waste and paddy straw employing earthworm consortium: Assessment of maturity time, microbial community structure, and economic benefit

Vermicomposting is usually performed with one earthworm species. However, use of a consortium of two or more species (Eisenia fetida, Eudrilus eugeniae, and Perionyx excavatus) is rare. Research on optimization of vermicomposting duration is also insufficient. Three earthworm species in various combinations were fed with cowdung mixed biowaste feedstock. Organic C, C/N ratio, compost respiration, coliform count, toxic metals, and alkalinity reduced at maturity; whereas, earthworm biomass, NPK availability, enzyme activity, microbial growth, and humic substances remarkably improved under consortium systems. Thus, the harvest quality was optimized sooner under vermicomposting (40-60 days) than composting (>100 days). Phospho-lipid fatty-acid (PLFA) analyses revealed the enriched variations in microbial community structure and fatty-acid profiles in consortium treated vermicomposts. Overall, the Eisenia+Eudrilus+Perionyx consortium produced the best quality compost in the shortest duration (40-50 days) followed by Eisenia+Eudrilus and Eisenia+Perionyx consortia. Tomato seed germination and root-shoot vigors were significantly greater in consortia mediated systems. Moreover, economic assessment confirmed the advantage of consortium mediated vermitechnology.