@article {PPA:PPA2506, title = {Infectivity and sporulation potential of Phytophthora kernoviae to select North American native plants}, journal = {Plant Pathology}, volume = {61}, year = {2011}, month = {04/2012}, pages = {224{\textendash}233}, publisher = {Blackwell Publishing Ltd}, abstract = {

Phytophthora kernoviae exhibits comparable epidemiology to Phytophthora ramorum in invaded UK woodlands. Because both pathogens have an overlapping geographic range in the UK and often concurrently invade the same site, it is speculated that P. kernoviae may also invade North American (NA) forests threatened by P. ramorum, the cause of Sudden Oak Death. This paper addresses the susceptibility of select NA plants to P. kernoviae, including measures of disease incidence and severity on wounded and unwounded foliage. The potential for pathogen transmission and survival was investigated by assessing sporangia and oospore production in infected tissues. Detached leaves of Rhododendron macrophyllum, Rhododendron occidentale and Umbellularia californica, and excised roots of U. californica and R. occidentale were inoculated with P. kernoviae and percent lesion area was determined after 6 days. Leaves were then surface sterilized and misted to stimulate sporulation and after 24 h sporangia production was assessed. The incidence of symptomless infections and sporulation were recorded. All NA native plants tested were susceptible to P. kernoviae and supported sporangia production; roots of U. californica and R. occidentale were both susceptible to P. kernoviae and supported sporangia production. Oospore production was also observed in U. californica roots. The results highlight the vulnerability of select NA native plants to infection by P. kernoviae, suggest that symptomless infections may thwart pathogen detection, and underscore the importance of implementing a proactive and adaptive biosecurity plan.

}, keywords = {forest biosecurity, host susceptibility, invasive disease, Phytophthora kernoviae}, issn = {1365-3059}, doi = {10.1111/j.1365-3059.2011.02506.x}, url = {http://dx.doi.org/10.1111/j.1365-3059.2011.02506.x}, author = {Fichtner, E. J. and D. M. Rizzo and Kirk, S.A. and Webber, JF} } @article {doi:10.1094/PHYTO-97-10-1366, title = {Detection, distribution, sporulation, and survival of Phytophthora ramorum in a California redwood-tanoak forest soil}, journal = {Phytopathology}, volume = {97}, number = {10}, year = {2007}, pages = {1366-1375}, doi = {10.1094/PHYTO-97-10-1366}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PHYTO-97-10-1366}, author = {Fichtner, E. J. and Lynch, S. C. and D. M. Rizzo} } @proceedings {680, title = {Persistence of Phytophthora ramorum and Phytophthora kernoviae in U.K. natural areas and implications for North American forests}, volume = {Gen. Tech. Rep. PSW-GTR-229}, year = {2009}, month = {04/2010}, pages = {83-84}, publisher = {U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station.}, address = {Santa Cruz, California}, author = {Elizabeth J. Fichtner and Rizzo, David M. and Webber,Joan and Kirk, Susan A. and Alistair Whybrow}, editor = {Susan J. Frankel and John T. Kliejunas and Katharine M. Palmieri} } @article {doi:10.1094/PDIS-03-10-0236, title = {Root infections may challenge management of invasive Phytophthora spp. in U.K. woodlands}, journal = {Plant Disease}, volume = {95}, number = {1}, year = {2011}, pages = {13-18}, abstract = {

Because sporulation of Phytophthora ramorum and P. kernoviae on Rhododendron ponticum, an invasive plant, serves as primary inoculum for trunk infections on trees, R. ponticum clearance from pathogen-infested woodlands is pivotal to inoculum management. The efficacy of clearance for long-term disease management is unknown, in part due to lack of knowledge of pathogen persistence in roots and emerging seedlings. The main objectives of this work were to (i) investigate whether both pathogens infect R. ponticum roots, (ii) determine the potential for residual inoculum of P. kernoviae to infect R. ponticum seedlings in cleared woodlands, and (iii) assess potential for R. ponticum roots to support survival and transmission of P. kernoviae. Roots of R. ponticum were collected from both unmanaged and cleared woodlands and assessed for pathogen recovery. Both P. ramorum and P. kernoviae were recovered from asymptomatic roots of R. ponticum in unmanaged woodlands, and P. kernoviae was recovered from asymptomatic roots from seedlings in cleared woodland. Oospore production of P. kernoviae was observed in naturally infected R. ponticum foliage and in inoculated roots. Roots also supported P. kernoviae sporangia production. The results of this study suggest that post-clearance management of R. ponticum regrowth is necessary for long-term inoculum management in invaded woodlands.

}, issn = {0191-2917}, doi = {10.1094/PDIS-03-10-0236}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PDIS-03-10-0236}, author = {Fichtner, E. J. and D. M. Rizzo and Kirk, S.A. and Webber, JF} } @article {doi:10.1094/PHYTO-99-5-0608, title = {Survival, dispersal, and potential soil-mediated suppression of Phytophthora ramorum in a California redwood-tanoak Forest}, journal = {Phytopathology}, volume = {99}, number = {5}, year = {2009}, note = {PMID: 19351257}, pages = {608-619}, doi = {10.1094/PHYTO-99-5-0608}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PHYTO-99-5-0608}, author = {Fichtner, E. J. and Lynch, S. C. and D. M. Rizzo} } @article {408, title = {Cypress mortality (mal del cipr{\'e}s) in the Patagonian Andes: comparisons with similar forest diseases and declines in North America}, journal = {European Journal of Forest Pathology}, volume = {29}, year = {1999}, month = {April 1999}, pages = {89{\textendash}96}, abstract = {

Summary Widespread mortality of Cordilleran cypress (Austrocedrus chilensis) occurs in developed and pristine forests in south-western Argentina and possibly south-eastern Chile. Affected trees may die rapidly but mortality is commonly preceded by several decades of severely restricted radial stem growth. Roots are often affected by one or more types of decay. Cypress mortality, locally termed {\textquoteleft}mal del cipres{\textquoteright}, is similar to a major forest disease in North America: Port-Orford-cedar (Chamaecyparis lawsoniana) root disease in Oregon and California and a major tree decline: Alaska yellow-cedar (Chamaecyparis nootkatensis) decline in south-east Alaska. This paper discusses several hypotheses concerning mal del cipres and compares current forest decline research in Patagonia with North America.

}, doi = {10.1046/j.1439-0329.1999.00133.x}, url = {http://dx.doi.org/10.1046/j.1439-0329.1999.00133.x}, author = {Filip, G. M. and Rosso, P. H.} } @proceedings {417, title = {{\textquoteleft}{\textquoteleft}Mal del cipr{\'e}s{\textquoteright}{\textquoteright} disease: analysis of the association between aerial symptoms and vitality of trees.}, year = {2009}, pages = {282{\textendash}3}, publisher = {USDA Forest Service, Pacific Southwest Research Station: Gen. Tech. Rep. PSW-GTR-221, 282{\textendash}3}, address = {Albany, CA, USA}, author = {Floria, MP and Greslebin, A. G.} } @article {3949, title = {Distribution of the Phytophthora disease of alder}, number = {Retrieved 12 June 2010.}, year = {2006}, publisher = {UK Forestry Commission}, url = {http://www.forestry.gov.uk/fr/INFD-737J2S}, author = {Forestry_Commission_Great_Britain} } @article {4187, title = {Gene~{\texttimes}~environment tests discriminate the new EU2 evolutionary lineage of Phytophthora ramorum and indicate that it is adaptively different}, journal = {Forest Pathology}, volume = {44}, year = {2013}, month = {06/2014}, pages = {219-232}, abstract = {

A new evolutionary lineage of the destructive introduced tree pathogen Phytophthora ramorum, EU2 lineage, was recently discovered attacking larch and other hosts in Northern Ireland and south west Scotland, UK. Sixteen {\textquoteleft}medium\ {\texttimes}\ agar concentration\ {\texttimes}\ incubation temperature{\textquoteright} stress environments were tested to find a rapid and repeatable method to discriminate the known EU2 lineage from the EU1, NA1 and NA2 lineages in culture, in particular from the EU1 already prevalent across the UK; and to investigate whether EU2 might be adaptively different. At 28{\textdegree}C on both Carrot agar and V8 juice agar, the mean radial growth rates of all four lineages were significantly different, with NA2\ \>\ EU2\ \>\ EU1\ \>\ NA1. At this temperature, EU2 colonies were not only phenotypically distinct from EU1 and all other lineages but on average grew three times as fast as EU1. This indicates that EU2 is adaptively different from EU1. Twelve days growth in the environment {\textquoteleft}V8A/2\% agar/28{\textdegree}C gave excellent discrimination of all four lineages in three repeat experiments, including clear discrimination of EU2 from EU1. Each lineage exhibited a distinctive colony pattern. The utility of this test environment was examined further by screening fresh UK isolates of unknown lineage from new larch outbreak sites alongside standard isolates. The lineage assignments predicted were corroborated by gene sequencing and RFLP profiling. These results also revealed that the EU2 lineage was present at several new larch sites in south west Scotland, whereas isolates from geographically adjacent areas such as the Isle of Mull, north west Scotland, the Isle of Man and north west England were all of EU1 lineage.

}, issn = {1439-0329}, doi = {10.1111/efp.12085}, url = {http://dx.doi.org/10.1111/efp.12085}, author = {Franceschini, S. and Webber, J. F. and Sancisi-Frey, S. and Brasier, C. M.} } @proceedings {946, title = {Proceedings of the sudden oak death third science symposium}, year = {2007}, month = {2008}, pages = {491 pp.}, publisher = {Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture}, address = {Santa Rosa, California}, abstract = {

The Sudden Oak Death Third Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. One hundred and seventeen submissions describing papers and posters on the following sudden oak death/ P. ramorum topics are included: biology, genetics, nursery, and wildland management, monitoring, ecology, and diagnostics.

}, keywords = {coast live oak, invasive species, Phytophthora ramorum, Sudden oak death, tanoak}, url = {http://www.fs.fed.us/psw/publications/documents/psw_gtr214/}, author = {Frankel, Susan J. and Kliejunas, John T. and Palmieri, Katharine M.} } @proceedings {944, title = {Proceedings of the sudden oak death second science symposium: the state of our knowledge}, year = {2005}, month = {2006}, pages = {571 pp.}, publisher = {Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture}, address = {Monterey, California}, abstract = {

The Sudden Oak Death Second Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Ninety papers and forty-six posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland management, monitoring, ecology, and diagnostics. Several papers on P. kernoviae and other forest Phytophthora species are also presented.

}, keywords = {coast live oak, invasive species, Phytophthora ramorum, Sudden oak death, tanoak}, url = {http://www.fs.fed.us/psw/publications/documents/psw_gtr196/}, author = {Frankel, Susan J. and Shea, Patrick J. and Haverty, Michael I.} } @article {4382, title = {Pest Alert: Phytophthora tentaculata.}, number = {December 18 2015}, year = {2015}, publisher = {Pacific Southwest Research Station, USDA Forest Service}, address = {Albany, CA . }, abstract = {

Phytophthora tentaculata has been detected in several California native plant nurseries and restoration sites. These are the first detections of P. tentaculata in the USA. Phytophthora tentaculata was initially noticed in a native plant nursery causing a severe root and crown rot in sticky monkey flower, Diplacus aurantiacus subsp. aurantiacus (Scrophulariaceae) in 2012 (figure 1). Since then it has been detected in four additional nurseries in three counties in CA in addition to three restoration sites where outplanted stock was found to be infected.

}, url = {http://www.suddenoakdeath.org/wp-content/uploads/2015/02/P.tentaculata.Pest_.Alert_.022315.pdf}, author = {Frankel, S and Swiecki, T and Bernhardt, E and Rooney-Latham, S and Blomquist, C} } @proceedings {945, title = {Proceedings of the sudden oak death fourth science symposium.}, year = {2009}, month = {2010}, pages = {378 pp.}, publisher = {Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture}, address = {Santa Cruz, California}, abstract = {

The Sudden Oak Death Fourth Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Ninety submissions describing papers or posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland management, monitoring, ecology, and diagnostics.

}, keywords = {coast live oak, invasive species, Phytophthora ramorum, Sudden oak death, tanoak}, url = {http://www.fs.fed.us/psw/publications/documents/psw_gtr229/}, author = {Susan J. Frankel and John T. Kliejunas and Katharine M. Palmieri} } @article {4710, title = {Phytophthora Introductions in Restoration Areas: Responding to Protect California Native Flora from Human-Assisted Pathogen Spread}, journal = {Forests}, volume = {11}, year = {2020}, month = {Nov-30-2020}, pages = {1291}, abstract = {

Over the past several years, plantings of California native plant nursery stock in restoration areas have become recognized as a pathway for invasive species introductions, in particular Phytophthora pathogens, including first in the U.S. detections (Phytophthora tentaculata, Phytophthora quercina), new taxa, new hybrid species, and dozens of other soilborne species. Restoration plantings may be conducted in high-value and limited habitats to sustain or re-establish rare plant populations. Once established, Phytophthora pathogens infest the site and are very difficult to eradicate or manage{\textemdash}they degrade the natural resources the plantings were intended to enhance. To respond to unintended Phytophthora introductions, vegetation ecologists took a variety of measures to prevent pathogen introduction and spread, including treating infested areas by solarization, suspending plantings, switching to direct seeding, applying stringent phytosanitation requirements on contracted nursery stock, and building their own nursery for clean plant production. These individual or collective actions, loosely coordinated by the Phytophthoras in Native Habitats Work Group ensued as demands intensified for protection from the inadvertent purchase of infected plants from commercial native plant nurseries. Regulation and management of the dozens of Phytophthora species and scores of plant hosts present a challenge to the state, county, and federal agriculture officials and to the ornamental and restoration nursery industries. To rebuild confidence in the health of restoration nursery stock and prevent further Phytophthora introductions, a voluntary, statewide accreditation pilot project is underway which, upon completion of validation, is planned for statewide implementation.

}, doi = {10.3390/f11121291}, url = {https://www.mdpi.com/1999-4907/11/12/1291/htm}, author = {Frankel, Susan J. and Conforti, Christa and Hillman, Janell and Ingolia, Mia and Shor, Alisa and Benner, Diana and Alexander, Janice M. and Bernhardt, Elizabeth and Swiecki, Tedmund J.} } @article {951, title = {Sudden oak death and Phytophthora ramorum in the USA: a management challenge}, journal = {Australasian Plant Pathology}, volume = {37}, year = {2008}, pages = {19{\textendash}25}, abstract = {

Oaks and tanoaks in California and Oregon coastal forests are being ravaged by sudden oak death. The exotic causal agent, Phytophthora ramorum, is an oomycete in the Straminipile group, a relative of diatoms and algae. P. ramorum also infects many popular horticultural plants (i.e. camellia and rhododendron), causing ramorum blight, with symptoms expressed as leaf spots, twig blight and shoot dieback. P. ramorum has raised important biosecurity issues, which continue to reverberate through the agriculture, forestry and horticulture industries as well as associated government management, regulatory and scientific agencies. The continued spread of this and other new Phytophthora spp. presents significant impetus for adjustments in the management and regulation of forest pathogens and nursery stock.

}, url = {http://www.publish.csiro.au/?paper=AP07088}, author = {Susan J. Frankel} } @article {4691, title = {Impact of weather variables and season on sporulation of Phytophthora pluvialis and Phytophthora kernoviae}, journal = {Forest Pathology}, volume = {50}, year = {2020}, month = {Mar-03-2020}, pages = {e12588}, abstract = {

Phytophthora pluvialis and Phytophthora kernoviae are the causal agents of important needle diseases on Pinus radiata in New Zealand. Little is known about the epidemiology of the diseases, making the development of control strategies challenging. To investigate the seasonality and climatic drivers of sporulation, inoculum traps, consisting of pine fascicles floating on water in plastic containers, were exchanged fortnightly at five sites in P.\ radiata plantations between February 2012 and December 2014. Sections of needle baits were plated onto selective media and growth of Phytophthora\ pluvialis and P.\ kernoviae recorded. To explore the generalizability of these data, they were compared to detection data for both pathogens from the New Zealand Forest Health Database (NZFHDB). Further, equivalent analyses on infection of Rhododendron ponticum by P.\ kernoviae in Cornwall, UK allowed the comparison of the epidemiology of P.\ kernoviae across different host systems and environments. In New Zealand, inoculum of P.\ pluvialis and P.\ kernoviae was detected between January{\textendash}December and March{\textendash}November, respectively. Inoculum of both species peaked in abundance in late winter. The probability of detecting P.\ pluvialis and P.\ kernoviae was greater at lower temperatures, while the probability of detecting P.\ pluvialis also increased during periods of wet weather. Similar patterns were observed in NZFHDB data. However, the seasonal pattern of infection by P.\ kernoviae in the UK was the opposite of that seen for sporulation in New Zealand. Phytophthora kernoviae was likely limited by warmer and drier summers in New Zealand, but by colder winter weather in the UK. These results emphasize the importance of considering both environmental drivers and thresholds in improving our understanding of pathogen epidemiology.

}, doi = {10.1111/efp.v50.210.1111/efp.12588}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/efp.12588}, author = {Fraser, Stuart and Gomez-Gallego, Mireia and Gardner, Judy and Bulman, Lindsay S. and Denman, Sandra and Williams, Nari M.} } @article {4527, title = { Las especies de Phytophthora en la Argentina}, journal = { Revista de Investigaciones Agricoles}, volume = {4}, year = {1950}, pages = {47-133}, author = {Frezzi, MJ} } @article {4450, title = {Effects of Soil Solarization and Trichoderma asperellum on Soilborne Inoculum of Phytophthora ramorum and Phytophthora pini in Container Nurseries}, journal = {Plant Disease}, volume = {100}, year = {2016}, month = {Jan-02-2016}, pages = {438 - 443}, abstract = {

Infested container nursery beds are an important source of soilborne Phytophthora spp. for initiating disease through movement with surface water or splashing onto foliage. We investigated the effects of soil solarization, alone or with subsequent amendment with a Trichoderma asperellum biocontrol agent, on the survival of Phytophthora spp. inoculum. In field trials conducted with Phytophthora ramorum in San Rafael, CA and with P. pini in Corvallis, OR, infested rhododendron leaf inoculum was buried at 5, 15, and 30 cm below the soil surface. Solarization for 2 or 4 weeks during summer 2012 eliminated recovery of Phytophthora spp. buried at all depths in California trial 1, at 5 and 15 cm in California trial 2, but only at 5 cm in Oregon. There was no significant reduction of Phytophthora spp. recovery after T. asperellum application. Although the population densities of the introduced T. asperellum at the 5-cm depth were often two- to fourfold higher in solarized compared with nonsolarized plots, they were not significantly different (P = 0.052). Soil solarization appears to be a promising technique for disinfesting the upper layer of soil in container nurseries under certain conditions.

}, issn = {0191-2917}, doi = {10.1094/PDIS-04-15-0453-RE}, url = {http://apsjournals.apsnet.org/doi/10.1094/PDIS-04-15-0453-RE}, author = {Funahashi, F. and Parke, J. L.} }