Agriculture Reference
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and C. paraputrificum (Citernesi et al. 1977). Alimentary canal of Lumbri-
cus rubellus and Octolasium lacteum were found to contain more numbers
of aerobes and anerobes (Karsten and Drake 1995) and culturable denitri-
fiers (Karsten and Drake 1997). List of vermicompost bacteria and their
beneficial traits is presented in Table 2.
Earthworms harbor 'nitrogen-fi xing' and 'decomposer microbes' in
their gut and excrete them along with nutrients in their excreta (Singleton
et al. 2003). Earthworms stimulate and accelerate microbial activities by
increasing the population of soil microorganisms (Binet et al. 1998), mi-
crobial numbers and biomass (Edwards and Bohlen 1996), by improving
aeration through burrowing actions. Vermicomposting modifi ed the origi-
nal microbial community of the waste in a diverse way. Actinobacteria and
Gammaproteobacteria were abundant in vermicompost, while conventional
compost contained more Alphaproteobacteria and Bacteriodetes, the bacte-
rial phylogenetic groups typical of non-cured compost (Vivas et al. 2009).
Total bacterial counts exceeded 10 -10 / g of vermicompost and it included
nitrobacter, azotobacter, rhizobium, phosphate solubilizers and actinomy-
cetes (Suhane 2007). Molecular and culture-dependent analyses of bacte-
rial community of vermicompost showed the presence of α-Proteobacteria,
β-Proteobacteria, γ-Proteobacteria, Actinobacteria, Planctomycetes, Fir-
micutes and Bacteroidetes (Yasir et al. 2009a). Several fi ndings showed
considerable increase in total viable counts of actinomycetes and bacteria
in the worm treated compost (Parthasarathi and Ranganathan 1998; Haritha
Devi et al. 2009). The increase of microbial population may be due to the
congenial condition for the growth of microbes within the digestive tract of
earthworm and by the ingestion of nutrient rich organic wastes which pro-
vide energy and also act as a substrate for the growth of microorganisms (Ti-
wari et al. 1989). The differences in microbial species, numbers and activity
between the earthworm alimentary canal or burrow and bulk soil indirectly
support the hypothesis that the bacterial community structures of these habi-
tats are different from those of the soil. Specifi c phylogenetic groups of bac-
teria such as Aeromonas hydrophila in E. foetida (Toyota and Kimura 2000),
fl uorescent pseudomonads in L. terrestris (Devliegher and Verstraete 1997),
and Actinobacteria in L. rubellus (Kristufek et al. 1993) have been found in
higher numbers in earthworm guts, casts, or burrows.
 
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