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【目的】对宁夏枸杞各药用部位内生细菌的分布特征、遗传多样性和抑菌活性进行分析。【方法】采用菌落计数和16S r RNA基因序列分析法研究枸杞内生细菌的分布特征、遗传多样性,采用琼脂扩散法测定其抑菌活性。【结果】从各药用组织器官中分离出内生细菌34株,隶属于7科11属,内生细菌的数量和群落组成存在明显的组织特异性,其数量表现为根皮>叶>花>果实,而多样性则表现为花>根皮>叶>果实。芽孢杆菌属为枸杞优势内生菌群,分布于所有组织中;抑菌实验结果表明有76.5%的内生菌对一种或多种病原菌的生长有抑制作用,芽孢杆菌属菌株R2、R7、L3和短波单胞菌属的R3拮抗番茄炭疽杆菌和玉米大斑病菌的能力较强,而多数菌株对大肠杆菌和金黄色葡萄球菌的抑制能力较弱。【结论】枸杞可培养内生细菌遗传多样性丰富,对植物病原菌有较强的抑制活性。
【Objective】 The distribution characteristics, genetic diversity and antibacterial activities of endophytic bacteria in medicinal parts of Lycium barbarum in Ningxia were analyzed. 【Method】 The distribution characteristics and genetic diversity of endophytic bacteria of Lycium barbarum were studied by colony counting and 16S rRNA gene sequence analysis. The antibacterial activities of endogenous bacteria were determined by agar diffusion method. 【Result】 Thirty-four strains of endophytic bacteria were isolated from various medicinal tissues and organs, belonging to 11 genera and 7 families. The number and the composition of endophytic bacteria were significantly tissue-specific, and their numbers were in the order of root bark> leaf> flower > Fruit, while diversity shows as flower> root bark> leaf> fruit. Bacillus belongs to the dominant endophytic flora of Chinese wolfberry and distributed in all tissues. The results of antibacterial test showed that 76.5% of endophytic bacteria could inhibit the growth of one or more pathogens. Bacillus strains R2, R7, R3 and short-wave genus of R3 antagonistic against Bacillus anthracis and Soleuca turcicum ability, and most strains of Escherichia coli and Staphylococcus aureus was weaker. 【Conclusion】 Wolfberry can cultivate endophytic bacteria rich in genetic diversity, strong inhibitory activity of plant pathogens.