红地球葡萄健康叶片内生细菌多样性分析

本研究利用平板分离方法和变性凝胶梯度电泳(DGGE)技术,分析了北京、成都、合肥、武汉等4个地区的红地球葡萄在开花期、成熟期和衰老期健康叶片中内生细菌的群落结构。平板分离培养结果表明不同地区葡萄叶片中的内生细菌数量在8.0×10~3~2.8×10~4CFU·g~(-1)之间,其中武汉地区最高;不同生长时期葡萄叶片中的内生细菌数量在0.8×10~3~1.5×10~4CFU·g~(-1)之间,其中成熟期数量最大。扩增16S rRNA基因序列鉴定,分离获得的内生细菌属于芽胞杆菌属、泛菌属、短小杆菌属、假单胞菌属和葡萄球菌属,芽胞杆菌属为常见菌群。DGGE分析结果显示,同一地区和同一生长时期的样品间相似性较高;不同地区以成都地区的内生细菌种类最丰富;不同生长时期以成熟期种类最多。对特征条带回收测序,结果显示不可培养细菌和未确认的海洋浮游细菌在葡萄叶片中大量存在。

Diversity of endophytic bacteria in healthy leaves of red globe grapes

Our study analysis the diversity of endophytic bacteria in red globe grape leaves sampled from four different regions (i.e. Beijing, Chengdu, Hefei and Wuhan), three different growth stages (i.e. flowering, maturing and senescence), by traditional plating isolation and denaturing gradient gel electrophoresis (DGGE) method. Results show that the population of endophytic bacteria in samples from different regions ranged from 8.0×10³ -2.8×10⁴ CFU·g^-1, between which the highest was from Wuhan. Population of endophytic bacteria in samples from different growth stages were between 0.8×10³ -1.5×10⁴ CFU·g^-1, and the largest was in mature period. All the strains isolated from leaves collected from different regions and different growth period were identified as Bacillus, Pantoea, Curtobacterium, Pseudomonas and Staphylococcus, based on 16S rRNA gene sequence aligment. Bacillus sp. was the dominant genus. DGGE profiles showed that samples from the same area or the same growth stage were of highly similarities, and easy to gather as a class. The species diversity was mainly expressed in samples from Chengdu and samples from mature stage. Uncultured bacteria and unrecognized marine planktonic bacteria were abounded in grape leaves as a result of cloning and sequencing for the characteristic bands.