Study On Microbial Remediation Of Apium Graveolens Continuous Cropping Obstacle In Inner Mongolia

The Taibus County located in the southern part of Xilin Gol League is known as"the Chinese celery first township"where the celery planting-area is about 2000hm2and the business about celery can produce about 3 million yuan per year. For the continuous cropping, a kind of celery disease named root-rot often happened recently over large area. The happening frequency of this kind disease is generally more than 30%, and the more serious situation is the completely loss in harvest on the heavy infected region. The traditional chemical pesticide has little effective on this kind disease. The happening of this disease has limited the development of local celery planting. In order to solve this problem effectively, the experiments study on screening higher efficient antagonistic actinomyces, and discusses that it can whether promote the growth of plant, and control the disease of plant or not. The main results are as follow:1.The occurrence of root rot disease in is closely related to the abnormal of microflora in celery rhizosphere soil and root surface soil in Inner Mongolia. In the rgizosphere soil, the number of bacteria, fungus of diseased plant in initial stage is less than healthy plant, while the number of bacteria, fungus of diseased plant in middle and late stage is much more than healthy plant. In the root surface soil, the number of bacteria of diseased plant in initial stage is less than healthy plant, while that in middle and late stage is much more than healthy plant. In initial, middle and late stage, the number of fungus of diseased plant is much more than healthy plant. In the reduction of the ratio of B / F in the rgizosphere soil and the root surface soil and the proportion of pathogenic fungi increasing and lead to the disease. The type of soil change form bacterium to fungi.2. From Inner Mongolia Taibus we isolated some fungi form infected plants and rhizosphere soil and root surface of soil. After morphological and molecular biology, we determine these are Fusarium sambucinum, Alternaria alternate, Fusarium oxysporum f. sp. Vasinfectum, Fusarium redolen, Plectosphaerella cucumerina.3. Using agar block and the growth rate method, we were screened five strong antagonistic former 621 actinomycetes. These stains number are A11, A12, A7, A28 and A49. After we analyzing its 16S rDNA sequence and turned out these are Streptomyces carnosus, Streptomyces pactum , Streptomyces globisporus , Streptomyces globisporus subsp. Globisporus and Streptomyces kanamyceticu.4.we studyed on the medium by adding CaCl2 and the method of microwave treatment have effect on the total number of actinomycetes, Streptomyces, Micromonospora, not identified kinds and the antagonistic actinomycetes. After adding CaCl2 to the medium, we found that the total number of actinomycetes, antagonistic actinomycetes and strong broad-spectrum of antagonistic strains increased. Similarly, the microwave treatment of tested soil in the GA, GACa and HA 3 kinds of media, we found out the total number of actinomycetes, Streptomyces, Micromonospora and unidentified genus were significantly increased, which show that the microwave could increase the amount of actinomycetes significantly.5. Pot experiments showed that when inoculating three pathogens, celery leaves and roots PPO enzyme activity and soluble protein content, POD activity and MDA content in leaves were significantly lower than the CK, while the cell membrane permeability and injury rate celery leaves higher than the CK. when inoculating three antagonistic actinomycetes, celery leaves and roots PPO enzyme activity and soluble protein content, POD activity and MDA content in leaves were significantly higher than the CK, while the cell membrane permeability and injury rate celery leaves lower than the CK. when mixed inoculating three pathogens and three antagonistic actinomycetes, celery leaves and roots PPO enzyme activity and soluble protein content, POD activity and MDA content in leaves were significantly higher than inoculated pathogens, while the cell membrane permeability and injury rate celery leaves lower than inoculated pathogens. Further proof, three actinomycetes contribute to the induction of celery resistance and inhibit the disease occurred.