Evaluation of the role of different plant biomass on the biological characteristics and reproduction of earthworms in vermicomposting process

In order to evaluate the influence of different plant biomass on vermiculture and vermicomposting, a greenhouse experiment was conducted for 90 days in Shahid Chamran university of Ahvaz during 2017. Experimental design was factorial based of RCB with 3 replications. First factor was three plant biomass types (sesame, wheat and sugarcane) and second factor was initial earthworm weight (60- 75 and 90 grams). Biological characteristics of earthworm and vermicompost’s chemical characteristics were measured. The results showed that the highest mature earthworm weight (122.79 g) and total earthworm weight (209.57 g) were belonged to sesame biomass with 90 g of earthworm weight. This treatment also had a highest phosphorus rate (158.5 mg/kg). The lowest mature earthworm weight (63.15 gr) was belonged to sugarcane biomass with 60 g of earthworm weight. Also, applying sesame biomass with 60 g earthworm weight had a highest efficiency ratio (2.8). In conclusion, we found that both plant biomass type and initial earthworm weight had different effect on earthworm biological characteristics. In other words, applying sesame plant biomass was suitable for increasing growth rate and maturity of earthworms. Also applying sugarcane plant biomass was suitable for increasing earthworm reproduction. In addition, for the optimum availability of nitrogen, phosphorus and potassium in the final vermicompost was appropriate to use sugarcane, sesame and wheat biomass, respectively.