Isolation of Predominant Bacterium from Gut of Earthworm Lampito mauritii for Effective Use in Soil Fertility

Lampito mauritii is an anecic earthworm living in the topsoil and it is geophytophagous in nature. This earthworm is an important soil macrofauna as it has the dual role of an 'ecosystem engineer' due to the ability to build burrows as well as 'keystone species' in soil food webs because of its function in degradation of organic wastes. The present study investigates the gut of this earthworm to find the most predominant bacterium harboured therein. Gut contents were regularly extracted and streaked on bacteriological media. The predominant type of colony was identified, isolated and streaked separately to get pure colonies. The microbe was subjected to several biochemical tests and also 16S rRNA sequencing for identification. On the basis of these tests, the bacterium was identified as Bacillus cereus. The microbe was used as a composting agent on solid wastes as a result of which good amount of plant nutrients, specially nitrogen (20.3 kg/ acre), phosphate (27.4 kg/acre) and potassium (52.1 kg/ acre) were found in the resultant manure. The compost thus obtained was then utilized for the production of vegetables with an attempt to protect soil environment, thus reducing the deleterious effects of chemical fertilizers.