Department of Plant Pathology, Sichuan Agricultural University, Chengdu 611130, P.R. China.
Plant Protection Station, Sichuan Provincial Department of Agriculture and Rural Affairs, Chengdu 610041, P.R. China.
Plant Dis. 2023 Oct;107(10):3248-3258. doi: 10.1094/PDIS-01-23-0005-RE. Epub 2023 Oct 25.
pv. causes kiwifruit bacterial canker and poses a major threat to the kiwifruit industry. This study aimed to investigate the genetic characteristics of the pv. population from kiwifruit in Sichuan, China. Sixty-seven isolates obtained from diseased plants were characterized using morphological features, multiplex-PCR, and multilocus sequence analysis (MLSA). The isolates exhibited the typical colony morphology of pv. Multiplex PCR amplification identified every isolate as pv. biovar 3. MLSA of the three housekeeping genes , , and , revealed that the reference strains of the five described biovars were clearly distinguished by a combined phylogenetic tree, and all of the tested isolates clustered with the reference strains of pv. biovar 3. Through a phylogenetic tree constructed from a single gene, it was found that gene alone could distinguish biovar 3 from the other biovars. Furthermore, all pv. isolates analyzed by BOX-A1R-based repetitive extragenic palindromic (BOX)-PCR and enterobacterial repetitive intergenic consensus (ERIC)-PCR clustered into four groups. The clustering results of BOX- and ERIC-PCR indicated that group III had the largest number of isolates, accounting for 56.72 and 61.19% of all 67 isolates, respectively, and the two characterization methods were similar and complementary. The results of this study revealed that the genomes of pv. isolates from Sichuan had rich genetic diversity but no obvious correlation was found between clustering and geographical region. This research provides novel methodologies for rapidly detecting kiwifruit bacterial canker pathogen and a molecular differentiation at genetic level of pv. biovar diversity in China.
pv. 引起猕猴桃溃疡病，对猕猴桃产业构成重大威胁。本研究旨在调查中国四川猕猴桃 pv. 种群的遗传特征。从病株中获得的 67 个分离物通过形态特征、多重 PCR 和多位点序列分析 (MLSA) 进行了表征。分离物表现出 pv. 的典型菌落形态。多重 PCR 扩增鉴定每个分离物均为 pv. 生物型 3。三个管家基因、和的 MLSA 显示，五个描述的生物型的参考菌株通过组合系统发育树清楚地区分，所有测试的分离物与 pv. 生物型 3 的参考菌株聚类。通过从单个基因构建的系统发育树发现，基因单独可以区分生物型 3 和其他生物型。此外，通过基于 BOX-A1R 的重复外基因回文 (BOX)-PCR 和肠细菌重复基因间共识 (ERIC)-PCR 分析的所有 pv. 分离物聚集成四个组。BOX 和 ERIC-PCR 的聚类结果表明，第 III 组的分离物数量最多，占所有 67 个分离物的 56.72%和 61.19%，两种表征方法相似且互补。本研究结果表明，四川 pv. 分离物的基因组具有丰富的遗传多样性，但聚类与地理区域之间没有明显的相关性。该研究为快速检测猕猴桃溃疡病病原菌提供了新的方法，并为中国 pv. 生物型多样性的遗传水平提供了分子差异。
