甘草内生细菌对4种植物病原菌的抑菌谱及其16S rRNA系统发育分析

旨在筛选对4种植物病原真菌具有拮抗活性的甘草内生细菌,为新疆甘草内生细菌的开发应用提供理论依据。采用平板对峙培养法从100株甘草内生细菌中筛选对石榴枯萎病甘薯长喙壳、草果叶斑病镰刀菌、草果假茎黑斑病小孢拟盘多毛孢、墨兰炭疽病胶孢炭疽菌等4个病原菌具有拮抗活性的菌株,并测定其16SrRNA基因序列,建立系统发育树对其进行初步鉴定。结果显示,61株菌株对甘薯长喙壳具有拮抗作用,其中13株菌的抑菌半径均大于15mm。进一步研究表明,10株菌对4种植物病原菌都表现出较高的抑菌能力。基于16Sr RNA基因序列分析与系统发育分析表明,其中11株菌为萎缩芽孢杆菌(Bacillus atrophaeus),另外2株菌分别为副氧化微杆菌(Microbacterium paraoxydans)和莫哈韦芽胞杆菌(B.mojavensis)。

Antimicrobial Spectrum of Endophytic Bacteria from Glycyrrhiza spp. Against Four Phytopathogens and Its Phylogenetic Analysis Based on 16S rRNA

In order to provide a theoretical basis for the exploration and utilization of endophytic bacteria of Glycyrrhiza, it is our aim to screen antagonistic strains of endophytic bacteria isolated from Glycyrrhiza against 4 kinds of plant pathogens.A total of 100 endophytic bacterias recovered from Glycyrrhiza were studied for its antagonism against Ceratocystis fimbriata,Pestalotiopsis microspora,Fusarium sp and Colletotrichum gloeosporioides Allesch by dual culture method. A phylogenetic tree were constructed based on its 16S rRNA gene sequences of the strains. The results indicated that 61 strains had inhibition activity to pomegranate wilt pathogen in vitro condition,and 13 strains showed strong antagonistic activity with an inhibition zone (>15 mm). The further study showed that 10 strains were high antagonistic activity against 4 kinds of plant pathogens. The identification result based on 16S rRNA gene sequence and phylogenetic tree demonstrated that 11 strains belonged to Bacillus atrophaeus and the other two strains belonged to Microbacterium paraoxydans and Bacillus mojavensis.