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Caused by Rhizoctonia solani (Rhizoctonia solani) infection sesame sesame Blight is a serious soil-borne diseases, widely distributed of sesame growing areas. Production on the application of chemical fungicides to control the disease is mainly, but serious damage to the environment. Currently, the case is still a lack of effective disease-resistant varieties of endophytic bacteria and their metabolites in the biological control of sesame damping-off, not only to overcome the above shortcomings, but also has the advantages of stable control efficiency, environmental protection and safety. Rhizoctonia solani target bacteria, sesame rhizosphere part from different growing areas of the endophytic bacteria for study, separation of endogenous bacterial screening of biocontrol bacteria, endogenous bacterial colonization and endogenous bacteria of the characteristics of a preliminary study, screened endophytes Blight animate anti-effect of sesame. The main findings are as follows: flat surface disinfection coating method, 399 endophytic bacteria from Daejeon 72 different varieties of healthy sesame rhizosphere The results show that the number and variety of different sesame varieties in the same planting area endophytes exist differences; same sesame varieties in different growing areas, the number and variety of different bacteria. Confrontation by plate culture method, the use of the PDA, KBM and MYG three different medium, 399 endophytic bacteria isolated from the original strain, screening antagonistic strains against Rhizoctonia solani. Results in three kinds of media on a total of 210 Rhizoctonia fungus (R.solani) antagonistic strains accounted for 52.6% of the total number of tested strains. The greenhouse pot biocontrol test, preliminary screening system for screening sesame damping-off of antagonistic bacteria, pathogens and soil the ratio of 1:1000 (W / W). With this system, through the mix of bacteria - in vivo screening sesame Blight antagonistic strains, flat screened 210 strains tested isolates were obtained animate anti effects sesame Rhizoctonia strains antagonistic strains; No. B16, b10, D31, e23, G10, I10, strain G10 biocontrol effect of up to 52%. The field plot biocontrol strains b10 and G10 test, the control efficiency of 31.8% and 42.5%, respectively. Chitosan (Chitosan) and chitin (Chitin) as the sole carbon source the transparent circle Determination the endogenous 210 the bacteria produced chitosanase (Chitosanase) and chitinase (Chitinase) capability, The results showed that 42 endophytic bacteria has a capacity of producing chitosanase the five bacteria has the ability of producing chitinase, respectively, 20% and 2% of the total separation of the total number; milk Tablet measured antagonistic bacteria producing protease (Prolease) the case, a total of 165 production protease, accounting for 78% of the total number of isolates. 6 potted screening of biocontrol characteristics research results show that the strain G10 have the capacity of producing chitosanase production capacity of chitinase, I10, six bacteria have the ability of producing protease; addition, the measured six strains on PDA plates for watermelon Fusarium wilt (Fusarium oxysporium), watermelon anthracnose fungus (Colletotrichum orbiculare), Gaeumannomyces (Gaeumannoyces graminis var.tritici), Sclerotinia sclerotiorum fungus (Sclerotinia sclerotiorum) inhibition of the bacteria capacity, the results show the 6 strains exhibit a broad spectrum of antibacterial activity; Meanwhile, G10 Strain KBM medium liquid shake flask fermentation, chitosan activity in the fermentation broth was measured, the results show, the fermentation 24h enzyme live up to 1.7U/mL activity unit. Selective medium were determined through the water agar of law and IRRIGATING law in two ways, the use of colloidal chitosan as the sole carbon source G10 strains found in sesame root internal colonization dynamic G10 strains sesame roots can be long-term colonization. Respectively using cultural characteristics, morphological characteristics, physiological and biochemical characteristics and 16S rDNA sequence analysis of G10 strains were identified to the genus Bacillus subtilis (Bacillus subtilis).
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