Screening Of High Efficient Cellulose Degrading Microbes And The Application Of Composite Microbial Inoculants In Composting Of Crop Straw

293 cellulose degrading strains were isolated and screened from the soils and composts,which consisted of 79 bacteria,121 actinomycetes and 93 fungi.Ten high cellulose degrading strains including 4 bacterias(b60,b62,b66,b68),4 actinomycetes (s28,s96,s98,s99,s106) and 2 fungi(f29,f53) were selected by Congo red agar and growth speed.The results of identification showed that four bacteria strains belonged to different genus,b60 was genus of Cellulomonas,b62 was genus of Pseudomonas,b66 and b68 were genus of Bacillus.s96,s98 and s99 belonged to genus of Sterptomyces,s106 belonged to genus of Micromonospora.f29 belonged to genus of Aspergillus and f53 belonged to genus of Trichoderma.By the means of orthogonal test with 10 screened strains and 1 strains of Aspergillus niger,1 strains of Cellulomonas carate,2 strains of azotobacter and the commercial product EM,3 highly effective combinations were obtained.The degradation rate for filter paper were combination 12＞combination 8＞combination 5.Combination 12 was used to study its adaptability to some environmental factors on the liquid medium.It showed that the optimal carbon source was microcrystalline cellulose and caroxymethy cellulose sodium salt,the appropriate nitrogen source was peptone and yeast extract,while the optimal medium pH and culture temperature were 6.5 and 30℃,respectively.And the optimal incubation time was 6 days.The enzyme characteristcs of cellulase of group 12 showed that the K_m for CMC-Ns was 0.32 g/L,V_max,was 0.15mg/(min·ml) in the condition of 60℃,pH 6.0.The molecular weights of outside cell cellulase of group 12 were 98.5kD and 61.3kD revealed by SDS-PAGE.The experiments were set up three treatments for aerobic compost text with crop straw including no-inoculant(CK₁),purchased microbial inoculants(CK₂),self-inoculantion of microbial group12(treatment T).11 indicators were tracked by temperature,water content,pH,C/N ratio,ash content,coarse fiber content,SOUR,seed germination index, the result showed that CK₂ and treatment T average C/N ratio is 19.27,average coarse fiber content is 21.25%,average SOUR is 0.035 mg O₂/(g·h·VS),average seed germination index is 101.3%.Through the four compost maturity indicators of variance analysis,the results showed that,there is a significant difference between the CK₁ and CK₂,CK₁ and treatment T of the C / N ratio and no significant difference between CK₂ and treatment T, and other three indicators have no significant difference among CK₁,CK₂ and treatment T.