| 364 endophytic bacteria and rhizoplane bacteria were isolated from capsicum annuum.L(Hai feng 12 and Qie men sweet pepper).Population densities of endophytic bacteria were found to be higher in the root tissue than in the leave tissue in the same breed of pepper. Generally, "Hai feng 12" had more kinds of endophytic bacteria than "Qie men sweet pepper".A total of 20 potencially antagonistic bacteria were screened by dual testing for in vitro antagonism towards 15 fungal pathogens which included Phytophthora capsici Leonian, Botrytis cinerea Pers. ex Fr, Pyricularia grisea (Cooke) Sacc.), Phytophthora melonis Katsura, Verticillium albo-atrum Reinke et Berthold., Colletotrichum capsici (Sydow) Butler and Bisby, Fusarium oxysporium (Schl.) f. sp. cucumerinum Qwen, Cladosporium cucumerinwn Ellis et Arthur, Phytophthora parasitica Destur, Fusarium oxysporum.f.sp.vasinfectum, Rhizoctonia solani Kohn, Helminthosporium turcicum Passerini, Alternaria longipes (Ellis et Everhart), Colletotrichum agaves Cavara, Cochliobolus sativus (Ito & Kurib) Drechsler ex Daster. The maximum inhibition zone radius was up to 11mm.The result from experment trial at greenhouse showed some bacteria from pepper had provided some biological disease control. For example, GF8, a rhizoplane bacteria, had been proved biological active against Rhizoctonia solani Kohn, Phytophthora capsici Leonian and Cladosporium cucumerinum Ellis et Arthur. The control efficiency reached 50%, 28.42% and 45.35% respectively.DIG High Prime DNA Labeling and Detection Starter KitI was used to detect nifHDK gene in 20 antagonistic bacteria. But nifHDK gene was not detected in bacteria.The 16S rDNA gene was used as a phylogenetic marker to analyse the diversity and taxonomy of bacteria obtained from pepper.They were identified into 6 genera: Burkholderia cepacia, Pseudomonas aeruginosa, Pseudomonas, Bacterium, Burkholderia, Brevibacillus reuszeri. YL35 needed further study because its sequence homology was only 93%.
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