Isolation And Characterization Of An Efficient Cellulose-Decomposing Strain R7 And Its Application In Field

In China after the crops harvested, the stalks will accumulate large. As a rich resource, stalks burning is a great waste and caused serious pollution to environment. An efficient fungi which can break down cellulose was isolated from zijin mountain soil. It is identified as Hypocrea sp.. Strain R7(Hypocrea sp.), YN1(Aspergillus sp.) and ACCC30166(Trich-oderma sp.) were combined as a combination and its decomposing character was studied.(1) The CMC-Na was used as selective medium. According to the hydrolysis circle, eight strains of fungi that have ability to decompose straw were isolated. An efficient strain R7 was got after comparing the enzyme activity of different strains. Strain R7 was identified as Hypocrea sp.(2) The affection of carbon source, nitrogen source, time, temperature and pH for enzyme production were studied. Glucose could inhibit enzyme production, as CMC and bran could promote it. Take CMC-Na as carbon source, ammonium nitrate as nitrogen source and at 30℃, it could reach its highest enzyme activity at the third day.(3) Solid fermentation was taken in the lab. The stalk reached its highest temperature at the forth day and fell down slowly at the tenth day. The carbon-nitrogen ratio reached 13.49. The combination of the three fungi had best ability to degration straw.(4) Some application was done in field. The samples were used to plant corn in lab and the soil that have straw with fungi had best way corn is growing. We did DGGE to the samples and found the changes of microbiology flora. It meant that the combination of fungi to degradation straw haw some help in improving crops.