02050nas a2200169   4500008004100000022001400041245009600055210006900151260001200220300001400232490000700246520153600253100001401789700001301803700001401816856005001830       2002                        eng d  a0191-291700aFirst report of bleeding canker caused by Phytophthora cactorum on horse chestnut in Turkey0 aFirst report of bleeding canker caused by Phytophthora cactorum   c06/2002  a697 - 6970 v863 a<p>Bleeding canker on horse chestnut (<em>Aesculus</em> sp.), caused by <em>Phytophthora cactorum</em> (Lebert and Cohn) Schröeter previously has been reported from the United States and Europe (1). In August 2000, it was found for the first time in a park in Ankara Province, Turkey. Symptoms included sparse yellowish brown foliage with abnormally small leaves, and dark-stained spots or dark brown necrosis of the bark on the trunk and main branches, with or without a reddish black gummy exudate. <em>P. cactorum</em> was isolated from tissues taken from the margins of necrotic bark. Pure cultures were slightly radiate, fluffy but not dense, and had short aerial hyphae when grown on carrot agar, potato dextrose agar, or V8 agar. Sporangia were ovoid, strongly papillate, and averaged 35.6 μm in length and 26.8 μm in width (range: 24 to 55 μm × 19 to 40 μm). The isolates were homothallic with smooth-walled paragynous oogonia ranging from 23.5 to 34.5 μm in diameter. To satisfy Koch's postulates, mycelium of <em>P. cactorum</em> was placed under the bark of six branches of healthy horse chestnut. Noninoculated wounds served as controls. Four months later a reddish black gummy exudate was observed oozing from the inoculated wounds, and the bark tissue was necrotic for 3 to 4 cm around each infection. <em>P. cactorum</em> was successfully reisolated from the necrotic bark tissue. Control wounds remained healthy. To our knowledge, this is the first report of this disease on horse chestnut in Asia Minor.</p>1 aIntini, M1 aGurer, M1 aOzturk, S  uhttp://dx.doi.org/10.1094/PDIS.2002.86.6.697C01798nas a2200181   4500008004100000022001400041245013300055210006900188300001400257490000700271520112900278653003201407100001701439700002101456700002201477700001701499856010001516       2006                        eng d  a1087-184500aGenetic characterization of the natural hybrid species Phytophthora alni as inferred from nuclear and mitochondrial DNA analyses0 aGenetic characterization of the natural hybrid species Phytophth  a511 - 5290 v433 a<p>The different subspecies of <em>Phytophthora alni, P. alni subsp. alni</em> (Paa), <em>P. alni subsp. uniformis (Pau)</em>, and <em>P. alni subsp. multiformis</em> (Pam), are recent and widespread pathogens of alder in Europe. They are believed to be a group of emergent heteroploid hybrids between two phylogenetically close <em>Phytophthora</em> species. Nuclear and mitochondrial DNA analyses were performed, using a broad collection of <em>P. alni</em> and two closely related species, <em>P. cambivora</em> and <em>P. fragariae</em>. (Paa) possesses three different alleles for each of the nuclear genes we studied, two of which are present in Pam as well, whereas the third matches the single allele present in Pau. Moreover, Paa displays common mtDNA patterns with both Pam and Pau. A combination of the data suggests that Paa may have been generated on several occasions by hybridization between Pam and Pau, or their respective ancestors. Pau might have <em>P. cambivora</em> as a species ancestor, whereas Pam seems to have either been generated itself by an ancient reticulation or by autopolyploidization.</p>10aInterspecific hybridization1 aIoos, Renaud1 aAndrieux, Axelle1 aMarÁais, BenoÓt1 aFrey, Pascal  uhttp://www.sciencedirect.com/science/article/B6WFV-4JS1TK3-1/2/aead0efc6dc22a393ebadec5b321185501377nas a2200217   4500008004100000022001400041245014600055210006900201260002900270300001400299490000600313520066300319653001500982653001300997653001501010100001701025700002401042700002101066700001701087856005501104       2007                        eng d  a1471-828600aCharacterization of microsatellite markers in the interspecific hybrid Phytophthora alni ssp. alni, and cross-amplification with related taxa0 aCharacterization of microsatellite markers in the interspecific   bBlackwell Publishing Ltd  a133–1370 v73 a<p><em>Phytophthora alni</em> ssp. <em>alni</em> is an interspecific hybrid oomycete causing a large-scale decay of alders throughout Europe. In this study we developed a set of 10 microsatellite markers that shows promise for population studies and for studying hybridization events between the parental species of the hybrid. Moreover, the genotype and the ploidy of the different subspecies of <em>P. alni</em> might be inferred from the quantitative ratio of amplified genome-specific alleles. Nine primer pairs cross amplified with the related species <em>Phytophthora cambivora</em> and <em>Phytophthora fragariae</em> and yielded distinct alleles.</p>10agenotyping10aoomycete10apolyploidy1 aIoos, Renaud1 aBarrés, Beno{\^ıt1 aAndrieux, Axelle1 aFrey, Pascal  uhttp://dx.doi.org/10.1111/j.1471-8286.2006.01554.x01806nas a2200181   4500008004100000022001400041245012800055210007100183260002500254300001200279490000800291520120300299100001701502700001901519700002101538700001701559856004801576       2005                        eng d  a0929-187300aSCAR–based PCR primers to detect the hybrid pathogen Phytophthora alni and its subspecies causing alder disease in Europe0 aSCAR–based PCR primers to detect the hybrid pathogen Phytophthor  bSpringer Netherlands  a323-3350 v1123 a<p>Since the 1990s, a new <em>Phytophthora</em> species hybrid has been jeopardizing the natural population of alders throughout Europe. This new <em>Phytophthora, P. alni</em>, has been suggested as a natural hybrid between two closely related species of <em>Phytophthora</em>. Little is known about the epidemiology of this pathogen, because its direct isolation is not always satisfactory. In this study we developed three pairs of Polymerase Chain Reaction (PCR) primers derived from Sequence Characterized Amplified Regions (SCAR) that allow discrimination among the three subspecies of <em>P. alni: P. alni subsp. alni, P. alni subsp. uniformis</em> and <em>P. alni subsp. multiformis</em>. These molecular tools were successfully used to detect <em>P. alni</em> directly in different substrates such as infested river water and soil, and necrotic alder bark, without the need for any prior baiting or isolation stages. An Internal Amplification Control (IAC) was included to help discriminate against false negative samples due to the potential presence of inhibitory compounds in DNA extracts. These molecular tools should be useful for epidemiological studies on this emerging disease.</p>1 aIoos, Renaud1 aHusson, Claude1 aAndrieux, Axelle1 aFrey, Pascal  uhttp://dx.doi.org/10.1007/s10658-005-6233-202032nas a2200169   4500008004100000245010500041210006900146300001400215490000700229520147100236100001701707700002401724700002501748700002101773700001701794856005101811       2007                        eng d00aDistribution and expression of elicitin genes in the interspecific hybrid oomycete Phytophthora alni0 aDistribution and expression of elicitin genes in the interspecif  a5587-55970 v733 a<p><em>Phytophthora alni</em> subsp. <em>alni</em>, <em>P. alni</em> subsp. <em>multiformis</em>, and <em>P. alni</em> subsp. <em>uniformis</em> are responsible for alder disease in Europe. Class I and II elicitin gene patterns of <em>P. alni</em> subsp. <em>alni</em>, <em>P. alni</em> subsp. <em>multiformis</em>, <em>P. alni</em> subsp. <em>uniformis</em>, and the phylogenetically close species <em>P. cambivora</em> and <em>P. fragariae</em> were studied through mRNA sequencing and 3' untranslated region (3'UTR)-specific PCRs and sequencing. The occurrence of multiple 3'UTR sequences in association with identical elicitin-encoding sequences in <em>P. alni</em> subsp. <em>alni</em> indicated duplication/recombination events. The mRNA pattern displayed by <em>P. alni</em> subsp. <em>alni</em> demonstrated that elicitin genes from all the parental genomes are actually expressed in this allopolyploid taxon. The complementary elicitin patterns resolved confirmed the possible involvement of <em>P. alni</em> subsp. <em>multiformis</em> and <em>P. alni</em> subsp. <em>uniformis</em> in the genesis of the hybrid species <em>P. alni</em> subsp. <em>alni</em>. The occurrence of multiple and common elicitin gene sequences throughout <em>P. cambivora</em>, <em>P. fragariae</em>, and <em>P. alni</em> sensu lato, not observed in other <em>Phytophthora</em> species, suggests that duplication of these genes occurred before the radiation of these species.</p>1 aIoos, Renaud1 aPanabières, Franck1 aIndustri, Beno{\^ıt1 aAndrieux, Axelle1 aFrey, Pascal  uhttp://aem.asm.org/content/73/17/5587.abstract02169nas a2200253   4500008004100000022001400041245013800055210006900193260002900262300001400291490000700305520136800312653002201680653001301702653002701715653002101742100001701763700001601780700001201796700001501808700001501823700002201838856005501860       2012                        eng d  a1365-305900aPotential susceptibility of Australian native plant species to branch dieback and bole canker diseases caused by Phytophthora ramorum0 aPotential susceptibility of Australian native plant species to b  bBlackwell Publishing Ltd  a234–2460 v613 a<p>Susceptibility to branch dieback caused by <em>Phytophthora ramorum</em> was tested using a detached branch assay for 66 Australian native plant species sourced from established gardens and arboreta in California. Six of these species were further tested for their susceptibility to bole cankers caused by <em>P.&nbsp;ramorum</em> using a sealed log assay. <em>Isopogon formosus</em> and <em>Eucalyptus denticulata</em> were identified as potentially highly susceptible Australian branch dieback hosts. Thirteen potentially tolerant Australian host species included <em>Banksia attenuata, B.&nbsp;marginata, E. haemastoma, E.&nbsp;regnans, Pittosporum undulatum</em> and <em>Billardiera heterophylla</em>. <em>Eucalyptus regnans</em> was identified as a potentially highly susceptible bole canker host, while <em>E.&nbsp;diversicolor</em> and <em>E.&nbsp;viminalis</em> were considered potentially tolerant species to bole cankers caused by <em>P.&nbsp;ramorum</em>. <em>Phytophthora ramorum</em> was able to infect all 66 species, as confirmed by reisolation. These results extend the known potential host range for <em>P.&nbsp;ramorum</em>, confirm it as a possible threat to Australian plant industries and ecosystems and highlight additional associated hosts that are important in the global horticultural trade, native forests and plantation forestry.</p>10ainvasive organism10aoomycete10aramorum branch dieback10aSudden oak death1 aIreland, K B1 aHüberli, D1 aDell, B1 aSmith, I W1 aRizzo, D M1 aHardy, St., G E J  uhttp://dx.doi.org/10.1111/j.1365-3059.2011.02513.x02306nas a2200205   4500008004100000022001400041245012500055210006900180260002900249300001400278490000700292520164900299100001701948700001601965700001201981700001501993700001502008700002202023856005502045       2011                        eng d  a1439-032900aPotential susceptibility of Australian flora to a NA2 isolate of Phytophthora ramorum and pathogen sporulation potential0 aPotential susceptibility of Australian flora to a NA2 isolate of  bBlackwell Publishing Ltd  a305–3200 v423 a<p><em>Phytophthora ramorum</em> is an invasive plant pathogen and the cause of considerable and widespread damage in nurseries, gardens and natural woodland ecosystems of the USA and Europe. It is considered to be a significant plant disease as it could cause biodiversity loss and severe economic losses in plant industries in areas where it is not yet known to exist, such as Australasia. Foliar susceptibility and sporulation potential were tested using detached-leaf assays for 70 Australian native plant species sourced from established gardens and arboreta in California using a NA2 isolate of <em>P. ramorum</em>. <em>Correa</em> ’Sister Dawn’, <em>Eucalyptus regnans</em>, <em>Isopogon cuneatus</em>, <em>I. formosus</em>, <em>Leptospermum scoparium</em>, <em>L. lanigerum</em> and <em>Melaleuca squamea</em> were identified as potentially highly susceptible host species. <em>Hedycarya angustifolia</em>, <em>Olearia argophylla</em>, <em>Phyllocladus aspleniifolius</em>, <em>Pittosporum undulatum</em> and <em>Podocarpus lawrencei</em> were identified as potentially resistant. All 70 species were able to be infected with <em>P. ramorum</em>, as confirmed by reisolation. Putative sporulating hosts include five members of the Myrtaceae, <em>Agonis flexuosa</em>, <em>Corymbia ficifolia</em>, <em>Eucalyptus haemastoma</em>, <em>E. delegatensis</em> and <em>E. viminalis</em>. As a part of a precautionary strategy, the potentially highly susceptible species found in this study are suitable candidates for targeted surveillance programmes in high-risk incursion areas of Australia and within the global horticultural trade.</p>1 aIreland, K B1 aHüberli, D1 aDell, B1 aSmith, I W1 aRizzo, D M1 aHardy, St., G E J  uhttp://dx.doi.org/10.1111/j.1439-0329.2011.00755.x02031nas a2200181   4500008004100000022001400041245010200055210006900157300001400226490000800240520141800248100002001666700002501686700002401711700002001735700002301755856007101778       2004                        eng d  a0953-756200aAFLP and phylogenetic analyses of North American and European populations of Phytophthora ramorum0 aAFLP and phylogenetic analyses of North American and European po  a378 - 3920 v1083 a<p>The genetic structure within and between USA and European populations of the emerging phytopathogen <em>Phytophthora ramorum</em> was examined. Four primer combinations were used for amplified fragment length polymorphism (AFLP) fingerprinting of 67 USA isolates from California and Oregon, and 18 European isolates from Belgium, Germany, The Netherlands, Spain and the UK. In addition, three DNA regions (ITS, <em>cox</em> II, and <em>nad</em> 5) of additional <em>Phytophthora</em> species were amplified by polymerase chain reaction, sequenced, and analysed to provide better phylogenetic understanding of <em>P. ramorum</em> within the genus <em>Phytophthora.</em> AFLP banding patterns indicate that the 85 isolates form two distinct lineages within a monophyletic group, distinct from the closely related outgroup species <em>P. lateralis.</em> With the exception of two isolates from an Oregon nursery, European and USA isolates clustered separately within individual clades. The AFLP profiles also indicate that a single clonal lineage dominates the North American population, while the European population consists of an array of mainly unique, closely related AFLP types. Sequences from the three DNA regions were identical among all <em>P. ramorum</em> isolates, and phylogenetic analysis indicates that <em>P. ramorum</em> is closely related to <em>P. lateralis</em> and <em>P. hibernalis.</em></p>1 aIvors, Kelly, L1 aHayden, Katherine, J1 aBonants, Peter, J M1 aRizzo, David, M1 aGarbelotto, Matteo  uhttp://www.sciencedirect.com/science/article/pii/S095375620861560901985nas a2200277   4500008004100000022001400041245015800055210006900213260002900282300001600311490000700327520111200334653001901446653001301465653002401478653000801502653002101510100001301531700001801544700001701562700002001579700002001599700001801619700001501637856005501652       2006                        eng d  a1365-294X00aMicrosatellite markers identify three lineages of Phytophthora ramorum in US nurseries, yet single lineages in US forest and European nursery populations0 aMicrosatellite markers identify three lineages of Phytophthora r  bBlackwell Publishing Ltd  a1493–15050 v153 a<p>Analysis of 12 polymorphic simple sequence repeats identified in the genome sequence of <em>Phytophthora ramorum</em>, causal agent of ‘sudden oak death’, revealed genotypic diversity to be significantly higher in nurseries (91% of total) than in forests (18% of total). Our analysis identified only two closely related genotypes in US forests, while the genetic structure of populations from European nurseries was of intermediate complexity, including multiple, closely related genotypes. Multilocus analysis determined populations in US forests reproduce clonally and are likely descendants of a single introduced individual. The 151 isolates analysed clustered in three clades. US forest and European nursery isolates clustered into two distinct clades, while one isolate from a US nursery belonged to a third novel clade. The combined microsatellite, sequencing and morphological analyses suggest the three clades represent distinct evolutionary lineages. All three clades were identified in some US nurseries, emphasizing the role of commercial plant trade in the movement of this pathogen.</p>10aexotic microbe10aoomycete10apopulation genetics10aSSR10aSudden oak death1 aIvors, K1 aGarbelotto, M1 aVries, I D E1 aRuyter-Spira, C1 aHekkert, TE., B1 aRosenzweig, N1 aBonants, P  uhttp://dx.doi.org/10.1111/j.1365-294X.2006.02864.x