00577nas a2200145   4500008004100000022001400041245007800055210006900133260006500202300001600267490000700283100001600290700001400306856011100320       1996                        eng d  a0191-291700aSurvival of Phytophthora lateralis in infected roots of Port Orford cedar0 aSurvival of Phytophthora lateralis in infected roots of Port Orf  b[St. Paul, Minn.: American Phytopathological Society], 1980-  a1075–10780 v801 aHansen, E M1 aHamm, P B  uhttps://forestphytophthora.org/references/survival-phytophthora-lateralis-infected-roots-port-orford-cedar00415nas a2200145   4500008004100000022001300041245005100054210005100105260002100156300001200177490000700189100001600196700001700212856004000229       1991                        eng d  a0027551400aSpecies of the Phytophthora megasperma complex0 aSpecies of the Phytophthora megasperma complex  cMay - Jun., 1991  a376-3810 v831 aHansen, E M1 aMaxwell, D P  uhttp://www.jstor.org/stable/375999900605nas a2200157   4500008004100000022001400041245011200055210006900167300001200236490000700248100001600255700001400271700001400285700001400299856013400313       1979                        eng d  a0032-081100aIsolation, incidence and management of Phytophthora in forest tree nurseries in the Pacific Northwest [USA]0 aIsolation incidence and management of Phytophthora in forest tre  a607-6110 v631 aHansen, E M1 aHamm, P B1 aJulis, AJ1 aRoth, L F  uhttps://forestphytophthora.org/references/isolation-incidence-and-management-phytophthora-forest-tree-nurseries-pacific-northwest02170nas a2200205   4500008004600000245006600046210006600112300001800178490000700196520156000203100001601763700001601779700001601795700001801811700001601829700001801845700001401863700001401877856007301891       Submitted                   eng d     00aEpidemiology of Phytophthora ramorum in Oregon tanoak forests0 aEpidemiology of Phytophthora ramorum in Oregon tanoak forests  a1133-1143(11)0 v383 a<p>We followed the local intensification and dispersal of <em>Phytophthora ramorum</em> Werres, De Cock, &amp; Man In’t Veld in Oregon tanoak (<em>Lithocarpus densiflorus</em> (Hook &amp; Arn.) Rehd.) forests from its initial detection in 2001 through 2006, coincident with a continuing eradication effort. The initial infested area included nine scattered sites below 400m elevation, close to the Pacific Ocean near Brookings, Oregon. In subsequent years, one-half of new infections were within 122m of a previous infection, and 79% of the newly detected trees occurred within 300m of a previously identified tree. Dispersal up to 4km was occasionally recorded. Initial infection occurred in the upper crowns of tanoak trees. The pathogen was recovered in rainwater collected beneath diseased tanoak trees in every month from November 2006 through October 2007. Twenty-four multilocus microsatellite genotypes were identified among 272 <em>P. ramorum</em> isolates collected from Curry County. Genotypic analysis provided independent estimates of time of origin of the Oregon infestation, its clustered distribution, and dispersal distances. In all sampling years, 60%-71% of the isolates belonged to the same multilocus genotype. In 2001, 12 genotypes were detected and new genotypes were identified in each of the subsequent years, but all isolates belonged to the same clonal lineage. Knowledge of local intensification of the disease and long-distance dispersal should inform both Oregon eradication efforts and national quarantine regulations.</p>1 aHansen, E M1 aKanaskie, A1 aProspero, S1 aMcWilliams, M1 aGoheen, E M1 aOsterbauer, N1 aReeser, P1 aSutton, W  uhttp://www.nrcresearchpress.com/doi/abs/10.1139/X07-217#.UNIUO7aKS0c01467nas a2200157   4500008004100000245011100041210006900152300001200221490000700233520090400240100001601144700001401160700001401174700001601188856010501204       1980                        eng d00aSurvival, spread, and pathogenicity of Phytophthora spp. on Douglas-fir seedlings planted on forest sites.0 aSurvival spread and pathogenicity of Phytophthora spp on Douglas  a422-4250 v703 a<p>Douglas-fir seedling stock infected in the nursery with <em>Phytophthora cryptogea, P. drechsleri, P. megasperma, P. cactorum</em>, and an unidentified <em>Phytophthora sp</em>. were outplanted on commercial forest sites to test survival of the diseased trees and of the pathogens. Mortality of trees initially classified in severe, moderate, and inconspicuous symptom classes at outplanting reached 61, 26, and 11%, respectively, after 18 mo. <em>Phytophthora</em> was recovered about equally from roots of trees in each symptom class (15, 13, and 12%). Surviving trees regenerated healthy roots above old lesions even though <em>Phytophthora</em> persisted. Disease spread was limited. None of 360 healthy trees planted 0.6 m downslope from diseased trees became infected, and only 2 of 720 healthy trees became infected after each was paired with a diseased tree in the same planting hole.</p>1 aHansen, E M1 aRoth, L F1 aHamm, P B1 aJulis., A J  uhttp://www.apsnet.org/publications/phytopathology/backissues/Documents/1980Abstracts/Phyto70_422.htm00444nas a2200133   4500008004100000245005900041210005900100300001200159490000700171100001600178700002500194700002100219856007000240       1999                        eng d00aFirst confirmation of Phytophthora lateralis in Europe0 aFirst confirmation of Phytophthora lateralis in Europe  a587-5870 v831 aHansen, E M1 aStreito, Jean-Claude1 aDelatour, Claude  uhttp://apsjournals.apsnet.org/doi/abs/10.1094/PDIS.1999.83.6.587B02063nas a2200145   4500008004100000245013900041210006900180300001000249490000700259520154500266100001601811700001501827700001401842856006101856       2005                        eng d00aSusceptibility of Oregon forest trees and shrubs to Phytophthora ramorum: a comparison of artificial inoculation and natural infection0 aSusceptibility of Oregon forest trees and shrubs to Phytophthora  a63-700 v893 a<p><em>Phytophthora ramorum</em> is an invasive pathogen in some mixed-hardwood forests in California and southwestern Oregon, where it causes sudden oak death (SOD) on some members of <em>Fagaceae, ramorum</em> shoot dieback on some members of <em>Ericaceae</em> and conifers, and <em>ramorum</em> leaf blight on diverse hosts. We compared symptoms of <em>P. ramorum</em> infection resulting from four different artificial inoculation techniques with the symptoms of natural infection on 49 western forest trees and shrubs; 80% proved susceptible to one degree or another. No single inoculation method predicted the full range of symptoms observed in the field, but whole plant dip came closest. Detached-leaf-dip inoculation provided a rapid assay and permitted a reasonable assessment of susceptibility to leaf blight. Both leaf age and inoculum dose affected detached-leaf assays. SOD and dieback hosts often developed limited leaf symptoms, although the pattern of midrib and petiole necrosis was distinctive. Stem-wound inoculation of seedlings correlated with field symptoms for several hosts. The results suggested that additional conifer species may be damaged in the field. Log inoculation provided a realistic test of susceptibility to SOD, but was cumbersome and subject to seasonal variability. Pacific rhododendron, salmonberry, cascara, and poison oak were confirmed as hosts by completing Koch’s postulates. Douglas-fir was most susceptible to shoot dieback shortly after budburst, with infection occurring at the bud.</p>1 aHansen, E M1 aParke, J L1 aSutton, W  uhttp://apsjournals.apsnet.org/doi/abs/10.1094/PD-89-006301381nas a2200253   4500008004100000245012200041210006900163300001400232490000700246520058000253653002800833653002400861653002500885653002200910653002900932100001600961700001400977700001800991700001801009700001301027700001401040700001501054856005801069       2003                        eng d00aPhytophthora nemorosa, a new species causing cankers and leaf blight of forest trees in California and Oregon, U.S.A.0 aPhytophthora nemorosa a new species causing cankers and leaf bli  a129–1380 v883 a<p><em>Phytophthora nemorosa</em>, a new species isolated from stem cankers on two species of <em>Fagaceae</em> and leaves of various hosts, is described. The new species resembles <em>P. ilicis</em> with homothallic, amphigynous antheridia and deciduous, semi-papillate sporangia, and has a related ITS-DNA sequence. Symptoms and host range are similar to <em>P. ramorum</em>, cause of Sudden Oak Death and leaf blight and shoot dieback diseases in California and Oregon forests, although <em>P. nemorosa</em> does not appear to cause wide-spread mortality of oak trees.</p>10aLithocarpus densiflorus10aPhytophthora ilicis10aPhytophthora ramorum10aQuercus agrifolia10aUmbellularia californica1 aHansen, E M1 aReeser, P1 aDavidson, J M1 aGarbelotto, M1 aIvors, K1 aDouhan, L1 aRizzo, D M  uhttp://www.mycotaxon.com/vol/abstracts/88/88-129.html02259nas a2200169   4500008004100000022001400041245010400055210006900159300001400228490000700242520170800249100001601957700001701973700001401990700001402004856007102018       1986                        eng d  a0007-153600aThe taxonomic structure of Phytophthora megasperma: Evidence for emerging biological species groups0 ataxonomic structure of Phytophthora megasperma Evidence for emer  a557 - 5730 v873 a<p>Nomenclatural uncertainty surrounds <em>P. megasperma</em> as various authors, working with limited groups of isolates, offer their interpretations of this species based on pathology, morphology, or cytology. We compared 93 isolates, including many described by others, for classical morphological features, growth behaviour and appearance, electrophoretic pattern of total proteins, chromosome number and nuclear DNA content. Nine distinct sub-groups were distinguished. While most groups could be distinguished by each of the criteria, protein electrophoresis was the most sensitive. The groups included: ALF, pathogenic to alfalfa, <em>n</em> = 12–15; SOY, pathogenic to soybean, <em>n</em> = 12–15; CLO, pathogenic to clover, <em>n</em> = 11–15; DF, pathogenic to Douglas fir, <em>n</em> = 17–24; AC, isolated from rosaceous fruit trees; and BHR, a major group obtained from a broad range of hosts. The last two groups, distinguished primarily by protein pattern, comprised at least four karyotypes: KI, <em>n</em> = 12–17; KII, <em>n</em> = 15–23; KIII, <em>n</em> = 22–28; and KIV, <em>n</em>= 26–34. All four karyotypes occur within the BHR protein group, suggesting a polyploid series within a closely related genotype.</p><p id="">Two broad lines of evolution are hypothesized, a legume line comprising ALF, SOY, CLO, and perhaps DF isolates, and a Broad Host Range line of AC and BHR isolates. Sub-groups within each line may represent emerging biological species, isolated by host specificity or karyotype. Taxonomic designation for the various groups must await confirmation of the hypothesis by demonstration of the extent of barriers to gene flow between the groups.</p>1 aHansen, E M1 aBrasier, C M1 aShaw, D S1 aHamm, P B  uhttp://www.sciencedirect.com/science/article/pii/S000715368680097301510nas a2200133   4500008004100000245006100041210006000102300001200162490000700174520111200181100001601293700002101309856004601330       1999                        eng d00aPhytophthora species in oak forests of north-east France0 aPhytophthora species in oak forests of northeast France  a539-5470 v563 a<p><em>Phytophthora</em> species were surveyed from the end of 1997 through July 1998 in oak forests in NE France. Healthy (Amance) or declining (Illwald) forests were compared. The <em>Phytophthora</em> population in both was diverse and locally abundant. At least eight species were present at Amance and six at Illwald. At Amance <em>Phytophthora</em> species had a localized distribution in water and low-lying soils. At Illwald distribution was more uniform apparently due to flooding events. Most often recovered were <em>P. citricola, P. gonapodyides</em> and <em>P. quercina. P. gonapodyides</em> was ubiquitous in water and colonized leaf debris. <em>P. quercina</em> was widely distributed in soil but not abundant, and was found in sites that did not otherwise appear to favor <em>Phytophthora</em>. No correlation was detected between presence of <em>Phytophthora</em> in soil and health of trees. Unusual combinations of environmental factors may be required for resident <em>Phytophthora</em> to have a detrimental impact on oaks. © 1999 Editions scientifiques et médicales Elsevier SAS.</p>1 aHansen, E M1 aDelatour, Claude  uhttp://dx.doi.org/10.1051/forest:1999070200483nas a2200145   4500008004100000022001400041245006200055210005900117300001400176490000700190100001600197700001400213700001400227856009600241       1989                        eng d  a0191-291700aTesting Port-Orford-cedar for resistance to Phytophthora.0 aTesting PortOrfordcedar for resistance to Phytophthora  a791–7940 v731 aHansen, E M1 aHamm, P B1 aRoth, L F  uhttps://forestphytophthora.org/references/testing-port-orford-cedar-resistance-phytophthora00474nas a2200121   4500008004100000022001400041245007600055210006900131300001200200490000700212100001600219856011700235       2008                        eng d  a1797-246900aAlien forest pathogens: Phytophthora species are changing world forests0 aAlien forest pathogens Phytophthora species are changing world f  a33–410 v131 aHansen, E M  uhttps://forestphytophthora.org/references/alien-forest-pathogens-phytophthora-species-are-changing-world-forests