Agriculture Reference
In-Depth Information
associated microbes. Vermiculture is a cost-effective tool for environmen-
tally sound waste management (Banu et al. 2001; Asha et al. 2008). Earth-
worms are the crucial drivers of the process, as they aerate, condition and
fragment the substrate and thereby drastically alter the microbial activity
and their biodegradation potential (Fracchia et al. 2006; Lazcano et al.
2008). Several enzymes, intestinal mucus and antibiotics in earthworm's
intestinal tract play an important role in the breakdown of organic macro-
molecules. Biodegradable organic wastes such as crop residues, munici-
pal, hospital and industrial wastes pose major problems in disposal and
treatment. Release of unprocessed animal manures into agricultural fields
contaminates ground water causing public health risk. Vermicomposting
is the best alternative to conventional composting and differs from it in
several ways (Gandhi et al. 1997). Vermicomposting hastens the decom-
position process by 2-5 times, thereby quickens the conversion of wastes
into valuable biofertilizer and produces much more homogenous materials
compared to thermophilic composting (Bhatnagar and Palta 1996; Atiyeh
et al. 2000a). Distinct differences exist between the microbial communi-
ties found in vermicomposts and composts and hence the nature of the
microbial processes is quite different in vermicomposting and composting
(Subler et al. 1998). The active phase of composting is the thermophilic
stage characterized by thermophilic bacterial community where intensive
decomposition takes place followed by a mesophilic maturation phase
(Lazcano et al. 2008; Vivas et al. 2009). Vermicomposting is a mesophil-
ic process characterized by mesophilic bacteria and fungi (Benitez et al.
1999). Vermicomposting comprises of an active stage during which earth-
worms and associated microbes jointly process the substrate and the matu-
ration phase that involves the action of associated microbes and occurs
once the worm's moves to the fresher layers of undigested waste or when
the product is removed from the vermireacter. The duration of the active
phase depends on the species and density of the earthworms involved
(Ndegwa et al. 2000; Lazcano et al. 2008; Aira et al. 2011). A wide range
of oganic wastes viz., horticultural residues from processed potatoes (Ed-
wards 1988); mushroom wastes (Edwards 1988; Tajbakhsh et al. 2008);
horse wastes (Hartenstein et al. 1979; Edwards et al. 1998); pig wastes
(Chan and Griffiths 1988; Reeh 1992); brewery wastes (Butt 1993); seri-
culture wastes (Gunathilagraj and Ravignanam 1996); municipal sewage
