AbstractSeveral groups (biovars) of the kiwifruit bacterial canker pathogen, Pseudomonas syringae pv. actinidiae, are found in Japan. Here, we sequenced and compared the 10 genomes of biovar 1, the major group in Japan, which is known as the phaseolotoxin producer.The kiwifruit bacterial canker pathogen, Pseudomonas syringae pv. actinidiae (Psa), was first described in Japan in 1989 (1). Subsequently, Psa was found in other kiwifruit-producing countries (2). Based on comparative analyses (2–4), Psa was categorized into several groups (biovars). The first Japanese group was named biovar 1 (Psa1), which was also later found in Italy and Korea. This biovar produces phaseolotoxin (2), a phytotoxin that inhibits arginine biosynthesis in host plants and results in bacterial canker symptom development. On the Psa1 chromosome, a large number of genes involved in phaseolotoxin biosynthesis are accumulated in an approximately 23 kb region (argK-tox cluster), which is contained in an exogenous genomic island (tox island) that Psa1 acquired in the past (2). However, some Psa1 strains found in Ehime Prefecture, Japan (the Ehime isolates) do not produce phaseolotoxin, although they seem to possess the argK-tox cluster (5). On the other hand, several Psa1 strains preserved in the NARO Genebank (https://www.gene.affrc.go.jp/index_en.php) may lack this cluster (2). Here, we selected 10 strains (Table 1) that represent Psa1 diversity and conducted comparative genome analyses.
Draft Genome Sequences of Nine Japanese Strains of the Kiwifruit Bacterial Canker Pathogen Pseudomonas syringae pv. actinidiae Biovar 3