Camellia oleifera is one of the four woody oil plants in the world, which is widely cultivated in South China. To examine the genetic diversity of C. oleifera in China, the diversity and genetic relationships among and within major populations of 109 varieties of C. oleifera were analyzed using ISSR markers. Twenty-three ISSR primers out of 49 primers yielded approximately 487 legible bands. A total of 335 of these bands were polymorphic markers, and the ratio of polymorphism was 68.86%. From the results, Zhejiang province showed the highest populations genetic diversity (H value 0.18), while Guangxi population showed the lowest genetic diversity (H 0.0851). Base on the bands, the genetic similarity coefficient ranged from 0.61 to 0.93 using NTSYS2.10e software. When coefficient was 0.75, 109 cultivars were divided into 11 categories and categories I contain 79 varieties by UPGMA cluster analysis. The test varieties divided into 7 sub-groups when categories were 0.75, which show a close genetic relationship. Results advised that Hunan is the main producing area of C. oleifera, with enriched C. oleifera variety and complex topography, and therefore has a high genetic diversity. Meanwhile, the main varieties of C. oleifera in Hubei are imported from Hunan, which results in fewer varieties and reduces the genetic diversity of C. oleifera. The ISSR profiles can improve C. oleifera germplasm management and provide potential determine correlations between different varieties and its distribution in different province.

Four separation methods of antimicrobial substances produced by CMN1308 (Bacillus amyloliquefaciens) were evaluated and selected according to number of antimicrobial substances and its activity in vitro. The results showed that extraction by acid precipitation of the fermentation supernatant of CMN1308 was the best with a diameter of inhibition zone of pathogen fungi P. expansum of 12.3 mm in a laboratory bioassay. Applying a silica thin layer chromatography (TLC), SDS-PAGE and other separation technologies we isolate antimicrobial substances, and the separated band were cut off for mass spectrometry analysis. The TLC of crude extract of CMN1308 show a topical band corresponding with the surfactin standard (Rf value =0.75), proved that the strain CMN1308 can produce this surface active compound. The mycoprotein extracted from CMN1308 was separated by Tricine-SDS-PAGE modified with the addition of urea in the separation gel. After mass spectrometric analysis and protein characterization, the isolated mycoprotein showed a maximum ion peak at M/Z of 2679 and molecular weight of 29.5 kDa, matching with protein flagellin. The extracellular antimicrobial protein of strain CMN1308 display four bands after urea-Tricine-SDS-PAGE, but after mass spectrometry analysis only two bands were identified. Band "A" with a maximum ion peak at M/Z of 1926 and molecular weight of 49.8 kDa, aligned with NCBI database, matching with DLDH (dihydrolipoamide dehydrogenase enzyme). Band "D" show the maximum ion peak at M/Z of 2936 and molecular weight of 22.4 kD, matching with a chitin binding protein. Thus, the strain CMN1308 has the potential to be developed as a commercial biological control agent for chestnut common pathogenic fungi.

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