番茄根内生芽孢杆菌的多样性和系统发育研究

旨在了解番茄根内生芽孢杆菌(Bacillus spp.)的分布和物种多样性。采用纯培养的方法从11 种不同的番茄栽培品种中分离纯化根内生芽孢杆菌，并通过16S rRNA基因序列的扩增、测序和分析进行分子鉴定及系统发育分析。从11 个样品中分离出芽孢杆菌65 株，分别鉴定为芽孢杆菌属(Bacillus)和短芽孢杆菌属(Brevibacterium)的18 个种。不同的番茄栽培品种分离的根内生芽孢杆菌的种类存在差异。系统发育分析表明分离的内生芽孢杆菌聚为几个小簇和不同种群，但是来源于不同番茄品种的同一种属的芽孢杆菌菌株的16S rRNA基因序列聚为同一分支，并且没有明显的差异。研究表明不同番茄栽培品种的根内生芽孢杆菌存在广泛的物种和分布多样性。

Diversity and Phylogenetic Analysis of Root Endophytic Bacillus in Tomato

The study aims to investigate the distribution and species diversity of tomato root endophytic Bacillus. The endophytic Bacillus strains were isolated from 11 tomato cultivars using the traditional pure culturing method, and the molecular identification and phylogenetic analysis were conducted with 16S rRNA amplification, sequencing and analysis. A total of 65 endophytic isolates were obtained and identified as 18 species of Bacillus and Brevibacterium. The types of endophytic Bacillus strains from different cultivars were different. Phylogenetic analysis indicated that Bacillus spp. were clustered into different branches and populations. However, there was no obvious sequence difference for the same species from different tomato cultivars. The study indicated that the root endophytic Bacillus from different tomato cultivars had extensive species and distribution diversity.