Reproduction Efficiency of Eisenia foetida and Substrate Changes During Vermicomposting of Organic Materials

ABSTRACT

Vermicomposting is the processing of organic substrates through digestion by worms, usually Eisenia foetida. The physico-chemical characteristics of the substrates and health of the worms are important parameter for effective vermicomposting. This study assessed reproduction efficiency and reproductive rate of E. foetida and changes in EC, pH, organic C, total Nitrogen and C:N ratio by vermicomposting different substrate mixtures. The study was performed as a completely randomized design with 10 treatments and 4 replicates. Manures from sheep and horse were tested alone and mixed at 50 and 75% with residues of alfalfa and wheat straw. Wheat straw was also tested alone and mixed at 75% with 25% chicken manure. E. foetida were added to the mixtures and allowed to process the substrate mixtures for three months. Final EC, pH, organic C and N levels of vermicompost were measured, as well as the reproductive efficiency and reproductive rate of the E. foetida. All measured characteristics of the finished vermicompost were significantly different depending on substrate. Substrates also changed to differing degrees during vermicomposting. Total C and EC increased in all substrates; and pH, total N, and C:N decreased in all substrates during vermicomposting The greatest change of EC was in the 25% alfalfa + 75% sheep manure mixture, which was 12.8 dS.m-1 initially and 18.6 dS.m-1 in finished vermicompost. Overall, pH declined and EC increased during the preparing of vermicompost.