Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, USA.
Department of Entomology, National Taiwan University, Taipei 106, Taiwan, ROC.
Microb Genom. 2021 Dec;7(12). doi: 10.1099/mgen.0.000727.
The economically important plant pathogen has been reported in multiple regions of the globe during the last two decades, threatening a growing list of plants. Particularly, subspecies causes Pierce's disease (PD) of grapevines, which is a problem in the USA, Spain, and Taiwan. In this work, we studied PD-causing subsp. populations and compared the genome sequences of 33 isolates found in Central Taiwan with 171 isolates from the USA and two from Spain. Phylogenetic relationships, haplotype networks, and genetic diversity analyses confirmed that subsp. was recently introduced into Taiwan from the Southeast USA (i.e. the PD-I lineage). Recent core-genome recombination events were detected among introduced subsp. isolates in Taiwan and contributed to the development of genetic diversity. The genetic diversity observed includes contributions through recombination from unknown donors, suggesting that higher genetic diversity exists in the region. Nevertheless, no recombination event was detected between subsp. and the endemic sister species , which is the causative agent of pear leaf scorch disease. In summary, this study improved our understanding of the genetic diversity of an important plant pathogenic bacterium after its invasion to a new region.
在过去的二十年中，经济上重要的植物病原菌已在全球多个地区被报道，威胁着越来越多的植物。特别是，亚种引起葡萄的葡萄皮尔氏病（PD），这是美国、西班牙和中国台湾地区的一个问题。在这项工作中，我们研究了引起 PD 的亚种种群，并将在台湾中部发现的 33 个分离株的基因组序列与来自美国的 171 个分离株和来自西班牙的两个分离株进行了比较。系统发育关系、单倍型网络和遗传多样性分析证实，亚种最近从美国东南部（即 PD-I 谱系）传入台湾。在台湾引入的亚种分离株中检测到近期核心基因组重组事件，导致遗传多样性的发展。观察到的遗传多样性包括来自未知供体的重组贡献，这表明该地区存在更高的遗传多样性。然而，在亚种和地方性姐妹种之间没有检测到重组事件，后者是梨叶灼伤病的病原体。总之，这项研究提高了我们对一种重要植物病原菌入侵新地区后的遗传多样性的理解。
