Song Yu-Rim, Hwang In Sun, Oh Chang-Sik
Department of Horticultural Biotechnology, College of Life Sciences, Kyung Hee University, Yongin 17104, Korea.
Plant Pathol J. 2020 Feb;36(1):29-42. doi: 10.5423/PPJ.OA.10.2019.0254. Epub 2020 Feb 1.
causes bacterial fruit blotch in , including watermelon. Although is a seed-borne pathogen, it can cause diverse symptoms in other plant organs like leaves, stems and fruits. To determine the infection routes of , we examined the virulence of six isolates (Ac0, Ac1, Ac2, Ac4, Ac8, and Ac11) on watermelon using several inoculation methods. Among six isolates, DNA polymorphism reveals that three isolates Ac0, Ac1, and Ac4 belong to Clonal Complex (CC) group II and the others do CC group I. Ac0, Ac4, and Ac8 isolates efficiently infected seeds during germination in soil, and Ac0 and Ac4 also infected the roots of watermelon seedlings wounded prior to inoculation. Infection through leaves was successful only by three isolates belonging to CC group II, and two of these also infected the mature watermelon fruits. Ac2 did not cause the disease in all assays. Interestingly, three putative type III effectors (Aave_2166, Aave_2708, and Aave_3062) with intact forms were only found in CC group II. Overall, our results indicate that can infect watermelons through diverse routes, and the CC grouping of was only correlated with virulence in leaf infection assays.
引起包括西瓜在内的细菌性果实斑点病。虽然是种子传播病原体，但它可在叶片、茎和果实等其他植物器官中引发多种症状。为确定的侵染途径，我们使用多种接种方法检测了六个分离株（Ac0、Ac1、Ac2、Ac4、Ac8和Ac11）对西瓜的毒力。在六个分离株中，DNA多态性显示三个分离株Ac0、Ac1和Ac4属于克隆复合体（CC）第二组，其他的属于CC第一组。Ac0、Ac4和Ac8分离株在土壤中种子萌发期间有效侵染种子，Ac0和Ac4还侵染接种前受伤的西瓜幼苗根部。只有属于CC第二组的三个分离株通过叶片成功侵染，其中两个还侵染了成熟西瓜果实。Ac2在所有试验中均未引发病害。有趣的是，仅在CC第二组中发现了三种具有完整形式的假定III型效应子（Aave_2166、Aave_2708和Aave_3062）。总体而言，我们的结果表明可通过多种途径侵染西瓜，并且的CC分组仅与叶片侵染试验中的毒力相关。
