Table 2. Genetic and pathogenic diversity of strains of Pseudomonas syringae according to the phylogenetic context of the strains. The presence or absence of genes was based on PCR detection.
| Cladea | Strainb | HRc |
Conserved genes in the canonical T3SS |
Psy642 hrcCf | Phage | gapA | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Disease on cantaloupe seedlings |
hopl1 |
CEL effectors |
hrp/hrc Cluster |
||||||||||
| Severityd | Incidencee | avrE | hrpW | hrpK | hrpL | hrcC | |||||||
| SZ-030 | Psy508g | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + |
| SZ-030 | − | 0.08 | 0.08 | − | − | − | − | − | − | + | + | + | |
| SZ-037 | − | 0.08 | 0.08 | − | − | − | − | − | − | + | + | + | |
| SZ-045 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| SZ-051 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| SZ-124 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| SZ-142 | − | 0.17 | 0.17 | − | − | − | − | − | − | + | + | + | |
| SZ-144 | − | 0.08 | 0.08 | − | − | − | − | − | − | + | + | + | |
| UB-015 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-185 | − | 0.08 | 0.08 | − | − | − | − | − | − | + | + | + | |
| UB-186 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-190 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-192 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-193 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-194 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-195 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-313 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | + | + | |
| UB-330 | − | ndh | nd | − | − | − | − | − | − | + | + | + | |
| Psy-642g | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + | |
| SZ-093 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + | |
| UB-184 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + | |
| UB-218 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + | |
| CC1504 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + | |
| USA-052 | − | 0.00 | 0.00 | − | + | + | + | − | − | + | − | + | |
| TA-002 | TA-043 | − | 1.67 | 1.00 | − | − | − | − | − | − | − | + | + |
| CCE-284 | − | 2.17 | 0.83 | − | − | − | − | − | − | − | − | + | |
| CCE-286 | − | 1.75 | 0.75 | − | − | − | − | − | − | − | − | + | |
| CCE-291 | − | 1.33 | 0.75 | − | − | − | − | − | − | − | − | + | |
| CCE-321 | − | 0.17 | 0.42 | − | − | − | − | − | − | − | − | + | |
| CCE-324 | − | 0.50 | 0.50 | − | − | − | − | − | − | − | − | + | |
| CCV-0050 | − | 1.17 | 1.00 | − | − | − | − | − | − | − | − | + | |
| CCV-0172 | − | 0.17 | 0.17 | − | − | − | − | − | − | − | − | + | |
| CCV-0178 | − | 2.91 | 1.00 | − | − | − | − | − | − | − | − | + | |
| CCV-0180 | − | 2.50 | 1.00 | − | − | − | − | − | − | − | − | + | |
| CSZ-0284 | − | 1.25 | 0.67 | − | − | − | − | − | − | − | − | + | |
| CSZ-0297 | − | 2.08 | 0.67 | − | − | − | − | − | − | − | − | + | |
| CC-1582 | − | 2.58 | 1.00 | − | − | − | − | − | + | − | − | + | |
| CC-0655 | + | 0.50 | 0.42 | − | + | − | − | − | + | − | − | + | |
| CC-0657 | + | 0.00 | 0.00 | − | + | − | + | + | + | − | − | + | |
| UB-246 | SZ-131 | − | 0.08 | 0.08 | − | − | − | − | − | − | − | + | + |
| UB-246 | − | 0.00 | 0.00 | − | − | − | − | − | − | − | + | + | |
| CC-1524 | CC-1419 | − | 0.00 | 0.00 | − | + | − | − | + | + | − | − | + |
| CC1418 | + | 0.00 | 0.00 | − | + | + | − | + | + | − | − | + | |
| CC1422 | + | 0.00 | 0.00 | − | + | + | − | + | + | − | − | + | |
| UB-169 | + | 0.00 | 0.00 | − | − | − | + | − | + | − | − | + | |
| UB-172 | + | 0.00 | 0.00 | − | − | − | + | − | + | − | − | + | |
| Cit7 | Cit7g | + | No known hostsi | + | + | + | + | + | + | − | − | + | |
| Group 1 | SZ-122 | − | 0.00 | 0.00 | − | − | + | + | + | − | − | − | + |
| SZ-026 | + | 0.25 | 0.25 | + | + | + | + | + | + | − | − | + | |
| SZ-046 | + | 0.25 | 0.25 | + | + | + | + | + | + | − | − | + | |
| SZ-049 | + | 0.33 | 0.25 | + | + | + | + | + | + | − | − | + | |
| SZ-145 | + | 0.00 | 0.00 | + | + | + | + | + | + | − | − | + | |
| CC-1569 | + | nd | nd | + | + | + | + | + | + | − | − | + | |
| DC3000g | + | 0.00 | 0.00 | + | + | + | + | + | + | − | − | + | |
| Group 2a | UB-419 | + | 2.83 | 1.00 | + | + | + | + | + | + | − | − | + |
| SZ-035 | + | 0.46 | 0.30 | + | + | + | + | + | + | − | − | + | |
| SZ-048 | + | 0.50 | 0.42 | + | + | + | + | + | + | − | − | + | |
| SZ-089 | + | 2.17 | 1.00 | + | + | + | + | + | + | − | − | + | |
| UB-197 | + | 0.00 | 0.00 | + | + | + | − | + | + | − | − | + | |
| UB-210 | + | 0.33 | 0.08 | + | + | + | − | + | + | − | − | + | |
| UB-421 | + | 2.83 | 1.00 | + | + | + | + | + | + | − | − | + | |
| Group 2b | USA-050 | − | 0.00 | 0.00 | − | − | − | − | − | − | + | − | + |
| CC0654 | + | 1.40 | 0.50 | + | + | + | + | + | + | − | − | + | |
| B728Ag | + | 0.00 | 0.00 | + | + | + | + | + | + | − | − | + | |
| Group 3 | 1448Ag | + | 0.00 | 0.00 | + | + | + | + | + | + | − | − | + |
| UB-370 | UB-370 | + | 0.00 | 0.00 | − | + | + | − | + | + | − | − | + |
| USA-102 | USA-046 | + | 0.00 | 0.00 | − | + | + | − | + | − | − | − | + |
| USA-106 | + | 0.00 | 0.00 | − | + | + | + | + | + | − | − | + | |
| USA-032 | USA-032 | + | 3.25 | 1.00 | − | + | + | − | + | + | − | − | + |
Abbreviations: CEL, conserved effector loci; HR, hypersensitive reaction; nd, not determined.
Clades are those described by Morris et al. (2010).
The origins of strains from non agricultural habitats used in this study are described in the supplementary table.
Hypersensitive reaction on tobacco (cv. Xanthi).
Mean intensity, on a scale of 0 to 4, of disease symptoms on 12 cantaloupe seedlings at 7 days after inoculation.
The proportion of 12 cantaloupe seedlings showing disease symptoms at 7 days after inoculation.
Detection of the Psy642 variant of the hrcC gene was based on primers different from those for detecting the canonical hrcC.
Reference strains described previously as follows: Psy508 (Mohr et al., 2008), Psy-642 (Clarke et al., 2010), Cit7 (Hirano and Upper, 1990), DC3000, B728A and 1448A (P. syringae Genome Resources: http://pseudomonas-syringae.org/home.html).
Not determined.
The pathogenicity of Cit7 has been previously well characterized. There are no known hosts and it is considered to be nonpathogenic (Hirano and Upper, 1990).