Growth and Reproductive Biology of Earthworms in Organic Waste Breakdown Under the Indian Condition

Abstract

Environmental improvement is an accepted national goal. Under the present condition of the acute energy crisis and environmental degradation with rise in population, it has become essential to develop an appropriate technology for the recovery of energy from non-conventional sources like organic wastes. India produces 350 million tonnes of organic wastes from different agricultural sources. Out of these, several million tonnes of plant nutrients are produced. Earthworm (verm) is known to be a good biological source for the recovery of vermifertilizer and vermiprotein from the organic wastes to be used in agro-ecosystem and aquaculture and poultry, respectively. Vermicomposting is a process of conversion of organic waste through the synergistic actions of epigeic earthworm and bacteria. When earthworms (endogeic or anecic) are applied for breakdown and stabilization of municipal solid wastes, the process is termed ‘vermistabilization’. The ultimate goal of both the processes is the production of plant-available nutrients and earthworm biomass (vermiprotein). Earthworm species to be selected for the process (1) should have great adaptability with respect to environmental factors, (2) should be capable of inhabiting high percentage of organic matter, (3) should be a prolific breeder (high fecundity) with high hatching success, and (4) should have short life cycle. Recent studies indicated that under Indian conditions epigeic species, such as Perionyx excavatus, Perionyx ceylanensis, Eudrilus eugeniae, Eisenia fetida, Eisenia andrei, can complete their life cycle in organic waste and produce vermicompost. Lampito mauritii, Polypheretima elongata, Drawida nepalensis, Drawida willsi, Metaphire posthuma, Metaphire houlleti can degrade organic matter in municipal sewage sludge which contains considerable amounts of sand particles. This chapter deals with the growth and reproduction of these organic waste degrading earthworms. Based on the study, suitable species for organic waste degradation are being suggested.