Influence of animal manures on the biology of temperate earthworm, Eisenia fetida in tropical semiarid climate.

Abstract

For understanding the potential utility in field scale production of vermicompost and vermiprotein economically, Eisenia fetida was cultured to establish the influence of (i) prevailing tropical semiarid (North-East region of Karnataka, India) environmental factors and (ii) different animal manures (cattle, horse and 1 : 1 mixture of cattle and horse) on its growth, reproduction and life span. In three forms of diet, growth (mg/d/g live weight of worm) was almost similar, but the biomass in cattle manure (565.7 +/- 15.3) was significantly more than horse manure (494.9 +/- 22.8) and 1 : 1 mixture (470.3 +/- 22.0). Mean cocoon production (per worm/week) in horse manure (0.16) was significantly (P<0.001) lower than that in cattle manure (1.6) and in 1 : 1 mixed manure (1.4). Cattle favoured biomass, growth and cocoon production. Horse manure inhibited cocoon production and the conserved energy in this process might have been added to the body weight almost equal to that in cattle manure. In 1:1 mixed manure, the biomass was less due to moderate cocoon production (presumably due to the stimulatory influence of 50% cattle manure) under semifavorable nutrients and environmental conditions. Fecundity of the worms declined with aging, despite favourable nutrients and environmental conditions. Worms survived up to 92, 68 and 66 weeks in cattle manure, 1 : 1 mixed manure and horse manure respectively.