Effect of Organic Materials from Agro-Industrial Wastes (Molasses and Distillery Slop) on Earthworms under Vermicomposting Using Cassava Waste

Abstract

The increasing of waste nowadays necessitates agro-industrial waste management, and vermicomposting technology has been offered as a viable method. However, before application of this method, a study of the effects of waste on earthworms is required. The objective of this study is to investigate the effects of organic material on earthworms as a result of the vermicomposting process. The experiment was conducted using completely randomized design with three replications. A toxicity test was administered to determine the effects of organic material (molasses and distillery slop from cassava industrial wastes) on the survival and growth of earthworms in vermicompost. The study found that after 7 days, 100% of the earthworms could survive under concentrations of molasses at rates of 1.25 - 3.75% and concentrations of distillery slop at rates of 6.25 - 25%. In addition, the application of organic materials (molasses and distillery slop) mixed with cassava industrial wastes increased the growth of earthworms. The earthworms had a survival rate of 67-100% after 4 weeks in the vermicompost treatment when molasses was mixed with cassava pulp and cassava peel, but without cassava pulp and cassava peel, the earthworms could not survive. Similar results were found with the application of distillery slop mixed with cassava pulp and cassava peel. Therefore, suitable rates of molasses and distillery slop use for earthworm survival are 1.25 - 3.75% and 6.25-25%, respectively. In conclusion, molasses and distillery slop can be used with cassava industrial waste material in the vermicomposting process.