The Importance Of Earthworms

Earthworms belong to the group of soil macroinvertebrates. All over the world 4200 species of earthworms are known and 590 species are reported from India (Julka et al., 2009). 53 species are recorded from western himalaya (Julka et al., 2005). On the basis of ecological niche Earthworms are divided in the main categories: epigeic, endogeic and anecics (Bouche, 1977). Earthworms are also called as intestine of earth and play important role in ecological processes of ecosystem ( Aristotle, 2008). They increase the soil fertility by helping in decomposition of organic matter, nitrogen fixation, increasing porosity of soil and water infiltration etc. (Lee, 1985) Among different macro invertebrates earthworms have been studied extensively in

Clostridium isolated from the gut of Eisenia foetida plays imopratant role in nitrogen fixation (Horn et al., 2003). Members of family Eudrilidae harbour Denitrifying bacteria (Citernesi et al., 1977). Lumbricus rubellus Hoffmeister and Octolasium lacteum (Oerl.) harbor a substantially higher number of bacteria capable of anaerobic growth than does the soil from which the worms are obtained (Karsten et al., 1995). Also, cellulose present plant cell wall is degraded by fungi like Aspergillus, Fusarium, Trichoderma and bacterial aspecies like Vibrio, Cellulomonas, Polyangia, Cytophaga, Streptomyces present in gut of earthworms. (Imshenetsky 1967,Ljungdahl and Eriksson, 1985). Bacterial species like Bacillus and Pseudomonas in addition to cellulose degradation also solubilise the soil phosphate ( Vijayakumar et al., 2009) (Imshenetsky 1967; Ljungdahl and Eriksson, 1985). On the other hand along with degradation of cellulose Aspergillus niger also degrades lignin and fungus is also known for lignin breakdown. ((Imshenetsky 1967; Ljungdahl and Eriksson, 1985; Krause et al., 2003; Malherbe and Cloete

Also the gut microflora of recently introduced exotic earthworms have not been studied. According to the recent studies the invasive earthworm species decrease the biomass, species density, species diversity and richness of fungi, bacteria and other microbes inhabiting the soil (Earthworm invasions of ecosystems devoid of earthworms: effects on soil microbes). Drawida japonica is also an exotic species inhabiting the Western Himalaya. The work on the gut microflora of this earthworm has not been done yet and present study is based on the isolation and characterisation of gut microflora of Drawida