糖蜜草内生固氮菌IS-PCR和16S rRNA基因全序列分析

采用插入序列指纹图谱分析（IS-PCR）和16SrRNA基因全序列分析，对来源于优良牧草——糖蜜草Melinis minutiflora Beauv．内生固氮菌进行研究．结果表明，糖蜜草中分离的内生固氮菌与产脂固氮螺菌模式菌株DSM1691的插入序列指纹图谱存在着差异；来源于糖蜜草的4株菌紧密地聚在一起，与GenBank中已知产脂固氮螺菌Azospirillum lipoferum的16SrRNA基因全序列有97％的序列相似性．初步确定糖蜜草中分离的内生固氮菌为一新类群的内生固氮菌．

Molecular study of endophytic nitrogen fixing bacteria isolated from Melinis minutiflora

Endophytic diazotrophs isolated from molassess grass, Melinis minutiflora,were studied by insert sequence(IS)-PCR fingerprinting patterns and full length of 16S rRNA gene sequences.IS-PCR fingerprinting showed that different patterns appeared between isolates and the type strain DSM 1691 of Azospirillum lipoferum;16S rRNA gene sequence analyses indicated that homology between isolates and known species Azospirillum lipoferum is 97%. These results suggested that isolates from molasses grass are possible a new group of endophytic diazotrophs closely related to Azospirillum lipoferum.