CDFA |
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TABLE 2. Symptomatic plant samples were collected from the field and subsamples divided for plating on selective medium for ND pathogen isolation or processed for DNA extraction and diagnosis with molecular markers.
CDFA Analysisa __________Mitochondrial Marker Systemb___________
Host | # Samples | Pathogen | Culture Isolation | P. ramorum ITS Amp. | Genus Specific | P. ramorum Specific | P. pseudosyringae Specific | P. nemorosa Specific | Sequence Confirmationc |
Umbellularia californica | 14 | P. ramorum | 12 | 14 | 14 | 14 | 0 | NDd | 4-P. ramorum |
| 9 | P. ilicis-likee | 9 | 0 | 5 | 0 | 5 | ND | 5-P. pseudosyringae |
| | | | 0 | 4 | 0 | 0 | 4 | 4- P. nemorosa |
| 6 | None | 0 | 0 | 3 | 0 | 0 | 3 | 3- P. nemorosa |
Rhododendron sp. | 6 | None | 0 | 0 | 2 | 0 | 0 | ND | 1-P. syringae |
2 | P. ramorum | 2 | 2 | 2 | 2 | 0 | ND | | |
1 | P. syringae | 1 | 0 | 1 | 0 | ND | ND | 1- P. syringae | |
Aesculus californica | 3 | ND | ND | 0 | 0 | 0 | ND | ND | |
Acer macrophyllum | 6 | ND | ND | 0 | 0 | 0 | 1-0, 5-ND | ND | |
Arbutus menziesii | 2 | ND | ND | 0 | 0 | 0 | ND | ND | |
Sequoia sempervirens | 3 | None | 0 | 0 | 0 | 0 | ND | ND | |
Sambucus sp. | 1 | None | 0 | 0 | 0 | 0 | ND | ND | |
Salal sp. | 1 | ND | ND | 0 | 0 | 0 | ND | ND | |
Pseudotsuga menziesii | 1 | ND | ND | 0 | 0 | 0 | ND | ND | |
Heteromelesarbutifolia | 2 | None | 0 | 0 | 0 | 0 | ND | ND | |
Rhamnus californica | 1 | None | 0 | 0 | 0 | 0 | ND | ND | |
| 1 | None | 0 | 0 | 0 | 0 | ND | ND | |
| 1 | Phytophthora sp. | 1 | 0 | 1 | 0 | 0 | ND | |
Manzanita sp. | 1 | P. ilicis-like | 1 | 0 | 0 | 0 | 0 | ND | |
| | | | | | | | | |
a Plant samples from the field were processed at the California Department of Food and Agriculture by plating on selective medium and confirming species identification based on morphological criteria and amplification of extracted DNA with the P. ramorum specific ITS primers of Garbelotto et al. (2002). Not all samples were cultured for pathogen isolation.
b Extracted DNA was amplified using the mitochondrial based Phytophthora genus-specific, P. ramorum, P. nemorosa, and P. pseudosyringae species specific primer pairs.
c The Phytophthora genus-specific fragment was sequenced and compared to sequence data from known cultures listed in Table 1 to confirm isolate identification.
d ND = Not Done.
eP. ilicis-like refers to either P. nemorosa or P. pseudosyringae as noted in Rizzo et al. (36), further classification based on morphology was not done.