INFLUENCE OF MOISTURE ON THE ACTIVITY OF PERIONYX EXCAVATUS (PERRIER) AND MICROBIAL–NUTRIENT DYNAMICS OF PRESSMUD VERMICOMPOST

Moisture play a crucial role in vermicomposting of pressmud (filter cake) (P). Five levels of moisture contents of pressmud (55-57%, 60-62%, 65-67%, 70-72% and 75-77%) at 31±2°C on earthworm activities (growth, reproduction and recovery rate of vermicompost) of Perionyx excavatus (Perrier)-an indigenous species and total microbial population, activity and nitrogen, phosphorous, potassium contents in the P vermicompost, over 60 days at an interval of 15, 30, 45 and 60 days have been studied. More and better worm biomass, cocoon production, hatchling number and rate of compost recovery were found in the 65- 67% moisture. Besides this level, 70-72% and 60-62% moisture were adequate. On the other hand, 55- 57% and 75-77% moisture did not have the desired effects on the growth and reproduction of earthworms and on vermicompost production. Enhanced microbial population and activity and nitrogen, phosphorous, potassium contents were found in fresh vermicomposts from 65-67% moisture than other moisture levels due to the ideal moisture of P for better multiplication of microbial population while passing through the worm gut with more activity, thereby enhancing the mineralization process resulting enhancement of nitrogen, phosphorous, potassium contents, whereas these decreased with decline in moisture content, immobilization and inactivation of microorganisms and/or increase in time (aging).

Keywords
Moisture content, pressmud, Perionyx excavatus, reproduction, vermicomposts, microbial activity, nutrient contents