Screening of Cellulolytic Actinomycetes for Decomposition of Agricultural Waste

Abstract

Each year, Viet Nam produces around 37 Mt of rice, 17-18 Mt of sugarcane and 4.5 Mt of maize and the total waste created by agriculture is estimated more than 50 Mt. Approximately nearly half of the straw is burned on the field, which is a common practice in intensive rice cultivation systems in this region and significantly impacts greenhouse gas emissions in the country. It has been a challenge for the government to reduce the burning of straw. Using microbials is a potential solution for the reason that fertilized straw, which contains essential nutrients as nitrogen, phosphorous and potassium, can be used as compost to enrich the soil. This study aims to screen for Actinomycetes with high cellulase activities for the decomposition of agricultural wastes. Among 21 isolated actinomycetes, 7 isolates including G1, G3, G11, D4, D5, DE2, X1 were selected with high enzymatic activities. The incubation of selected strains with rice straw and cane bagasse indicated that the ability of all these strains to degrade agricultural wastes. Rice straw showed better degradation results in comparison to sugarcane bagasse. The strains G3 and D4 showed the best degradation performance after 12 d of incubation. The remaining substrate including rice straw and sugarcane bagasse after incubation in turn with D4 and G3 were both 10.5%.