Draft Genome Sequence of Ralstonia pseudosolanacearum (R. solanacearum phylotype I) Strain Cq01 Isolated from Grafted Benincasa hispida var. Chieh-qua in China

Ralstonia solanacearum species complex (RSSC) is a vascular soil-borne plant pathogen with an unusually broad host range. Traditionally, the group has been subdivided into 5 race based on the differences in host range. Recent reports propose to separate RSSC into three species: R. solanacearum, R. pseudosolanacearum, and R. syzygii. R. pseudosolanacearum strain Cq01 was isolated from grafting Benincasa hispida var. Chieh-qua plant with bacterial wilt in Guangxi, China, and it was determined to be race 1 biovar 3. The strain Cq01 was a close relative of the R. solanacearum model strain GMll000 (race 1, biovar 3, phylotype I), but they showed significant differences in the pathogenicity to Cucurbitaceae plants, although they were in accordance with the pathogenicity to other plants. The draft genome sizes of the strain Cq01 was 5.88 Mb, with 66.81% GC content. Comparison of the genome of strain Cq01 to that of strain GMll000 (GenBank accession numbers NC_003295.1 and NC_003296.1), the strain Cq01 had 707 specific gene, which may be related to its host specificity.

青枯雷尔氏菌物种复合体（Ralstonia solanacearum species complex, RSSC）是一类具有极宽宿主范围的维管束土传植物病原菌。传统上，该类群被划分为5个生理小种（race）。近期研究提出将RSSC划分为3个物种：青枯雷尔氏菌（R. solanacearum）、假青枯雷尔氏菌（R. pseudosolanacearum）以及蒲桃青枯雷尔氏菌（R. syzygii）。假青枯雷尔氏菌菌株Cq01分离自中国广西患青枯病的嫁接节瓜（Benincasa hispida var. Chieh-qua）植株，经鉴定为1号生理小种、3号生物型（biovar 3）。该菌株与青枯雷尔氏菌模式菌株GMll000（1号生理小种、3号生物型、系统发育群I（phylotype I））亲缘关系相近，但二者对葫芦科（Cucurbitaceae）植物的致病性存在显著差异，不过对其他植物的致病性则表现一致。菌株Cq01的草图基因组大小为5.88 Mb，GC含量为66.81%。将菌株Cq01的基因组与模式菌株GMll000的基因组（GenBank登录号：NC_003295.1与NC_003296.1）进行比较后发现，菌株Cq01拥有707个特异性基因，这些基因可能与其宿主特异性相关。