Agriculture Reference
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Burrows 1988; Nardi et al. 1988; Edwards 1998). Plant growth stimulating
substances of microbial origin were isolated from tissues of
Aporrectodea
longa, L. terrestris
and
Dendrobaena rubidus
and indole like substances
were detected from the tissue extracts of
A. caliginosa, L. rubellus
and
E. foetida
which increased the growth of peas (Nielson 1965) and dry
matter production of rye grass (Graff and Makeschin 1980). A. trapezoids
aided in the dispersal of Rhizobium through soil resulting in increased root
colonization and nodulation of leguminous plants (Bernard et al. 1994).
Use of earthworm casts in plant propagation promoted root initiation, in-
creased root numbers and biomass. The hormone-like effect produced by
earthworm casts on plant metabolism, growth and development causing
dwarfi ng, stimulation of rooting, internode elongation and precociousness
of fl owering was attributed to the fact of presence of microbial metabolites
(Tomati et al. 1987; Edwards 1998). Earthworm casts stimulated growth
of ornamental plants and carpophore formation in
Agaricus bisporus
when
used as casing layer in mushroom cultivation (Tomati et al. 1987). Aque-
ous extracts of vermicompost produced growth comparable to the use of
hormones such as auxins, gibberellins and cytokinins on Petunia, Begonia
and Coleus, providing solid evidence that vermicompost is a rich source
of plant growth regulating substances (Grappelli et al. 1987; Tomati et al.
1987, 1988). Addition of vermicompost at very low levels to the growth
media dramatically increased the growth of hardy ornamentals
Chamaecy-
paris lawsonian, Elaeagnus pungens, Pyracantha spp., Viburnum bodnan-
tense, Cotoneaster conspicus
and
Cupressocyparis leylandi
. Cucumber
(Hahn and Bopp 1968), dwarf maize (Sembdner et al. 1976) and coleus
bioassays (Edwards et al. 2004) evidenced that vermicompost contained
appreciable amounts of cytokinins, gibberellins and auxins respectively.
Maize seedlings dipped in vermicompost water showed marked difference
in plumule length compared to normal water indicating that plant growth
promoting hormones are present in vermicompost (Nagavallemma et al.
2004). Comparative studies on the impact of vermiwash and urea solution
on seed germination, root and shoot length in
Cyamopsis tertagonoloba
proved that vermiwash contained hormone like substances (Suthar 2010).
High performance liquid chromatography (HPLC) and gas chromatogra-
phy-mass spectroscopy (GC-MS) analyses of aqueous extracts of cattle
