Effect of Nutrient Supplementation and Microbial Inoculation on Enrichment of Vermicompost Using Earthworm (Eisenia foetida sav.)

An enrichment study on vermicomposting of nutrient supplemented and microbially inoculated mixture of mustard crop residue and farm weeds with fresh cattle dung using Eisenia foetida was conducted in pits. Mixture of composting material was supplemented with 0.5 per cent urea, 1.0 per cent beneficiated rock phosphate, 0.15 per cent of ferrous and zinc sulphate and inoculated with lignocellulolytic microorganisms (Trichoderma viride, Cellulomonase fimi and Bacillus sp.), Azotobacter chroococcum, Bacillus megaterium and 500 adult earthworms pit^-1 were released according to treatments making seven combinations. During vermicomposting, composting mixtures were analysed for cellulase activity and microbial populations. At harvest, fresh vermicompost yield, earthworm density, C : N ratio, nutrient contents and humus fractions were recorded. Results revealed that combination of both nutrient supplementation and microbial inoculation positively influenced in increasing the macro and micro nutrient content, humus fractions, earthworm density and quality of vermicompost in respect of lower C : N ratio and less fresh vermicompost yield. Cellulase activity and microbial (bacteria, fungi and actinomycetes) populations were higher in enriched vermicomposting pit than control during the process of decomposition.