Agriculture Reference
In-Depth Information
ity and for the strong retention of nutrients (Shi-wei and Fu-zhen 1991).
Uptake of nitrogen (N), phosphorus (P), potassium (K) and magnesium
(Mg) by rice (
Oryza sativa
) plant was highest when fertilizer was applied
in combination with vermicompost (Jadhav et al. 1997). N uptake by
ridge gourd (
Luffa acutangula
) was higher when the fertilizer mix con-
tained 50% vermicompost (Sreenivas et al. 2000). Apart from providing
mineralogical nutrients, vermicomposts also contribute to the biological
fertility by adding beneficial microbes to soil. Mucus, excreted through
the earthworm`s digestive canal, stimulates antagonism and competi-
tion between diverse microbial populations resulting in the production of
some antibiotics and hormone-like biochemicals, boosting plant growth
(Edwards and Bohlen 1996). In addition, mucus accelerates and enhances
decomposition of organic matter composing stabilized humic substanc-
es which embody water-soluble phytohormonal elements (Edwards and
Arancon 2004) and plant-available nutrients at high levels (Atiyeh et al.
2000c). Adding vermicasts to soil improves soil structure, fertility, plant
growth and suppresses diseases caused by soil-borne plant pathogens, in-
creasing crop yield (Chaoui et al. 2002; Scheuerell et al. 2005; Singh et al.
2008). Kale (1995) reported the nutrient status of vermicomposts with or-
ganic carbon 9.15-17.98%, total nitrogen 0.5-1.5%, available phosphorus
0.1-0.3%, available potassium 0.15%, calcium and magnesium 22.70-70
mg/100 g, copper 2-9.3 ppm, zinc 5.7-11.5 ppm and available sulphur
128-548 ppm.
Effects of a variety of vermicomposts on a wide array of fi eld crops
(Chan and Griffi ths 1988; Arancon et al. 2004b), vegetable plants (Ed-
wards and Burrows 1988; Wilson and Carlile 1989;Subler et al. 1998; Ati-
yeh et al. 2000b), ornamental and fl owering plants (Edwards and Burrows
1988; Atiyeh et al. 2000c) under greenhouse and fi eld conditions have
been documented. Vermicomposts are used as alternative potting media
due to their low-cost, excellent nutrient status and physiochemical charac-
ters. Considerable improvements in plant growth recorded after amending
soils with vermicomposts have been attributed to the physico-chemical
and biological properties of vermicomposts.
Vermicompost addition favorably affects soil pH, microbial population
and soil enzyme activities (Maheswarappa et al. 1999) and also reduces
the proportion of water-soluble chemical, which cause possible environ-
