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 |
|
|
Heteromeles arbutifolia |
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.
e P. 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.