Vermicomposting is proven to be an effective way for nutrient cycling, converting large quantities of organic waste into value added product (vermicast). In order to harness the potential of earthworms in vermicomposting, selection of earthworm species that are able to consume large quantity of waste, and moreover, produce vermicast with high nutrient content is important. This experiment was carried out to compare the efficacy of Perionyx excavatus (PE) and Eudrilus eugeniae (EE) in vermicomposting rice straws. Ten earthworms were introduced into each vermibin containing grinded rice straw. The vermicast produced was collected periodically. The experiment was terminated when 70% of rice straw had decomposed. The plant nutrient contents and humic acids in vermicast were analysed. Vermicast of PE contained higher concentrations of total and available N, P, K and Mg while EE vermicast contained higher total and available Ca. Humic acid content was also found to be higher in EE vermicast. EE took 134 days while PE took 171 days to complete vermicomposting, thus, plant nutrient content generated per day in vermicast EE was higher compared to PE. Using EE in vermicomposting would contribute significantly towards practicing sustainable agricultural by recycling large amount of organic waste rice straw into value added high plant nutrient content vermicast. Key words: Earthworm biomass, decomposition rate, humic acid, agronomy.
