@article {Baccal{\textperiodcentered}1998261, title = {Austrocedrus chilensis mortality in the Nahuel Huapi National Park (Argentina)}, journal = {Forest Ecology and Management}, volume = {109}, number = {1-3}, year = {1998}, pages = {261 - 269}, abstract = {

Decline and mortality of Austrocedrus chilensis occurs throughout its natural distribution in Argentina. The problem was noted several decades ago but its causes are unknown. The aim of this work is to investigate the association between the occurrence of the decline and site characteristics considered to be relevant from the ecological point of view. A multivariate analysis is carried out using topographic and climatic information, obtained from 32 sites, within the limits of the Nahuel Huapi National Park, showing a wide range of decline and mortality incidence. Results of this study suggest that an ecological pattern of tree decline and mortality exists. The A. chilensis forests seem more prone to developing symptoms when occurring at sites with higher precipitation and not very high altitudes. To the eastern limit of its distribution, where precipitation is substantially low, A. chilensis forests show no symptoms of decline. It is, thus, hypothesized that sites with relatively poor soil drainage are more prone to develop symptoms. However, it is not clear whether high soil moisture directly affects roots or it produces a more suitable environment for root pathogen proliferation and infection.

}, keywords = {Decline, incidence, Saturated soil, Slope gradient}, issn = {0378-1127}, doi = {DOI: 10.1016/S0378-1127(98)00250-3}, url = {http://www.sciencedirect.com/science/article/B6T6X-3TW94FH-V/2/a6dc0b47a09acf8d6091e66f27b29502}, author = {Nora B. Baccal{\'a} and Pablo H. Rosso and Mar{\`I}a Havrylenko} } @article {JPH:JPH1079, title = {PCR-based DNA Markers for identifying hybrids within Phytophthora alni}, journal = {Journal of Phytopathology}, volume = {154}, number = {3}, year = {2006}, pages = {168{\textendash}177}, publisher = {Blackwell Verlag GmbH}, abstract = {

Two pairs of oligonucleotide primers were designed for the polymerase chain reaction (PCR)-based detection and differential identification of naturally occurring interspecific hybrid types (subspecies) of Phytophthora alni, all of which cause collar rot of alder trees. Primer pairs were derived from randomly amplified polymorphic DNA (RAPD) fragments that were unique to various subspecies of this alder pathogen. The primer pair set, SAP1/SAP2 (SAP), was derived from a 0.93-kb RAPD fragment amplified from P. alni ssp. alni. The primer pair set, SWAP1/SWAP2 (SWAP), was derived from a 1.13-kb fragment amplified from P. alni ssp. uniformis. Patterns of SAP and SWAP amplification enabled distinction among the three subspecies. No PCR products were amplified from isolates of 31 other Phytophthora spp. examined, including P. cambivora and P. fragariae, the suspected progenitors of P. alni. The SAP and SWAP primer sets were able to detect a minimum of 10\ pg of DNA from pure cultures or DNA extracted from as few as 10 zoospores. Pathogen DNA could also be amplified directly from bark lesions of artificially inoculated and naturally infected common alders and from lesions developed on common cherry-laurel leaves used in baiting the pathogen from infested soil. Direct detection of pathogen DNA from alder tissue using SAP and SWAP primer sets should prove useful in developing measures for effective quarantine and management of P. alni.

}, keywords = {Alnus, oomycete, Phytophthora alni, polymerase chain reaction markers, species hybrids}, issn = {1439-0434}, doi = {10.1111/j.1439-0434.2006.01079.x}, url = {http://dx.doi.org/10.1111/j.1439-0434.2006.01079.x}, author = {Bakonyi, J. and Nagy, Z. {\'A}. and {\'E}rsek, T.} } @article {doi:10.1094/PDIS-91-6-0705, title = {Phytophthora spp. associated with forest soils in eastern and north-central U.S. oak ecosystems}, journal = {Plant Disease}, volume = {91}, number = {6}, year = {2007}, pages = {705-710}, doi = {10.1094/PDIS-91-6-0705}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PDIS-91-6-0705}, author = {Balci, Y. and Balci, S. and Eggers, J. and MacDonald, W. L. and Juzwik, J. and Long, R. P. and Gottschalk, K. W.} } @article {EFP:EFP617, title = {Involvement of Phytophthora species in white oak (Quercus alba) decline in southern Ohio}, journal = {Forest Pathology}, volume = {40}, number = {5}, year = {2010}, pages = {430{\textendash}442}, publisher = {Blackwell Publishing Ltd}, abstract = {

This study was initiated to investigate the possible role of Phytophthora species in white oak decline (Quercus alba) in southern Ohio at Scioto Trail State Forest. Surveys demonstrated the presence of four species of Phytophthora including one novel species. By far, the most common species was P.\ cinnamomi; P.\ citricola and P.\ cambivora were isolated infrequently. In few instances, P.\ cinnamomi was isolated from fine roots and necroses on larger roots. No special pattern of incidence was found, but P.\ cinnamomi was more commonly isolated from greater Integrated Moisture Index values suggesting moist lower bottomlands favour this Phytophthora species. When tree crown condition was examined relative to the presence of Phytophthora, no significant association was found. However, roots of declining P.\ cinnamomi-infested trees had 2.5 times less fine roots than non-infested and healthy trees, which was significantly different. The population densities of P.\ cinnamomi from declining trees were significantly greater than from healthy trees, suggesting increased pathogen activity that has the potential to cause dieback and decline and possibly the cause of a reduced fine root amount found on declining trees.

}, issn = {1439-0329}, doi = {10.1111/j.1439-0329.2009.00617.x}, url = {http://dx.doi.org/10.1111/j.1439-0329.2009.00617.x}, author = {Balci, Y. and Long, R. P. and Mansfield, M. and Balser, D. and MacDonald, W. L.} } @article {4042, title = {Phytophthora quercetorum sp. nov., a novel species isolated from eastern and north-central USA oak forest soils}, journal = {Mycological Research}, volume = {112}, year = {2008}, month = {08/2008}, pages = {906 - 916}, abstract = {

Isolates belonging to an undescribed Phytophthora species were frequently recovered during an oak forest soil survey of Phytophthora species in eastern and north-central USA in 2004. The species was isolated using an oak leaf baiting method from rhizosphere soil samples collected from Quercus rubra, Q. macrocarpa, and Q. phellos. This species is formally described as P. quercetorum. It is homothallic and has aplerotic oogonia and paragynous antheridia. It produces papillate sporangia (occasionally bipapillate) of ovoid-elongated shapes. Its temperature optimum for growth is ca 22.5\ {\textdegree}C with the upper limit of ca 32.5\ {\textdegree}C. P. quercetorum differs from the morphologically related P. quercina in producing distinct submerged colony-patterns, different growth-temperature requirements, and oogonial shapes and sizes. Phylogenetic analyses using seven nuclear loci supported P. quercetorum as a novel species within clade 4, closely related to P. arecae, P. palmivora, P. megakarya, and P. quercina.

}, issn = {09537562}, doi = {10.1016/j.mycres.2008.02.008}, url = {http://www.sciencedirect.com/science/article/pii/S0953756208000841}, author = {Yilmaz Balci and Balci, Selin and Jaime E. Blair and Sook-Young Park and Seogchan Kang and Macdonald, William L.} } @article {4077, title = {A diverse range of Phytophthora species are associated with dying urban trees}, journal = {Urban Forestry \& Urban Greening}, year = {2013}, month = {9/2013}, abstract = {

Surveys of dying vegetation within remnant bushland, parks and gardens, and streetscapes throughout the urban forest of Perth and the South-west of Western Australia revealed symptoms typical of those produced by Phytophthora species. A total of nine Phytophthora species, including P. alticola, P. multivora, P. litoralis, P. inundata, P. nicotianae and P. palmivora were isolated. In addition, three previously undescribed species, Phytophthora aff. arenaria, Phytophthora aff. humicola and Phytophthora sp. ohioensis were isolated. Isolates were recovered from a wide range of native and non-native host genera, including Agonis, Allocasuarina, Brachychiton, Calothamnus, Casuarina, Corymbia, Dracaena, Eucalyptus, Ficus, Pyrus and Xanthorrhoea. Phytophthora multivora was the most commonly isolated species. Out of 230 samples collected 69 were found to be infected with Phytophthora. Of those 69, 54\% were located within parks and gardens, 36\% within remnant bushland, and 10\% within streetscapes. These pathogens may play a key role in the premature decline in health of the urban forest throughout Perth, and should be managed according to the precautionary principle and given high priority when considering future sustainable management strategies.

}, issn = {16188667}, doi = {10.1016/j.ufug.2013.07.009}, url = {http://dx.doi.org/10.1016/j.ufug.2013.07.009}, author = {P.A. Barber and Paap, T. and Burgess, T. I. and Dunstan, W. and G.E.St.J. Hardy} } @book {4254, title = {Phytophthora basal canker of red maple}, series = {Plant Pathology Circular}, volume = { No. 361}, year = {1993}, publisher = {Fla. Dept. Agric. \& Consumer Services. Division of Plant Industry}, organization = {Fla. Dept. Agric. \& Consumer Services. Division of Plant Industry}, address = {Gainseville, FL. }, url = {http://www.freshfromflorida.com/content/download/11368/144504/pp361.pdf}, author = {Barnard, E.L. and Mitchell, D.J.} } @article {436, title = {Hongos Aphyllophorales (Basidiomycetes) que causan pudriciones en Austrocedrus chilensis}, journal = {Boletiacuten de la Sociedad Argentina de Botaacutenica}, volume = {31}, year = {1996}, pages = {201-216}, author = {Barroetave{\~n}a, C. and Rajchenberg, M.} } @article {PPA:PPA1961, title = {A new threat to UK heathland from Phytophthora kernoviae on Vaccinium myrtillus in the wild}, journal = {Plant Pathology}, volume = {58}, number = {2}, year = {2009}, pages = {393{\textendash}393}, publisher = {Blackwell Publishing Ltd}, issn = {1365-3059}, doi = {10.1111/j.1365-3059.2008.01961.x}, url = {http://dx.doi.org/10.1111/j.1365-3059.2008.01961.x}, author = {Beales, P. A. and Giltrap, P. G. and Payne, A. and Ingram, N.} } @article {4569, title = {Genotypic diversity of Phytophthora cinnamomi and P. plurivora in Maryland{\textquoteright}s nurseries and Mid-Atlantic forests}, journal = {Phytopathology}, year = {2017}, month = {Jul-02-2017}, abstract = {

Genetic diversity of two Phytophthora species, P. cinnamomi (102 isolates) and P. plurivora (186), commonly encountered in Maryland nurseries and forests in the Mid-Atlantic United States was characterized using amplified fragment length polymorphism (AFLP). Expected heterozygosity and other indices suggested a lower level of diversity among P. cinnamomi than P. plurivora. Hierarchical clustering showed P. cinnamomi isolates separated into four clusters, and two of the largest clusters were closely related, containing 80\% of the isolates. In contrast, P. plurivora isolates separated into six clusters, one of which included approximately 40\% of the isolates. P. plurivora isolates recovered from the environment (e.g. soil, water) were genotypically more diverse than those found causing lesions. For both species, isolate origin (forest vs. nursery or among nurseries) was a significant factor of heterozygosity. Clonal groups existed within P. cinnamomi and P. plurivora and included isolates from both forest and nurseries, suggesting that a pathway from nurseries to forests or visa verse exists.

}, issn = {0031-949X}, doi = {10.1094/PHYTO-05-16-0215-R}, url = {http://apsjournals.apsnet.org/doi/10.1094/PHYTO-05-16-0215-R}, author = {Beaulieu, Justine and Ford, Blain B and Balci, Yilmaz} } @proceedings {4338, title = {Kauri (Agathis australis) Under Threat From Phytophthora?}, volume = {General Technical report PSW-GTR-221}, year = {2007}, month = {2009}, pages = {74{\textendash}85}, publisher = {U.S. Department of Agriculture, Forest Service Pacific Southwest Research Station}, address = {Monterey, California}, abstract = {

Five species of Phytophthora have been recorded from Agathis australis (kauri) or soil in kauri forests: P. cinnamomi, P. cryptogea, P. kernoviae, P. nicotianae and Phytophthora taxon Agathis (PTA) initially recorded as P. heveae. P. cinnamomi has been found widely in natural stands and has been linked with ill-thrift and occasional tree death, especially in regenerating stands on poorly drained sites. PTA, which is known from fewer natural stands, is associated with a collar rot, causing large bleeding lesions near the ground, yellowing foliage, and tree death. The other three species have only been reported once. ITS sequence studies of PTA show it belongs with, but is distinct from, P. heveae in ITS clade 5. Cultural and molecular studies indicate a close relationship with P. katsurae. It is proposed that PTA may be introduced to New Zealand, but too few isolates are available to determine whether genetic variability of this species provides support for this hypothesis. Recent surveys have found collar rot is widely distributed across the natural range of kauri. Typically, affected stands are relatively small in size. Size class distributions indicate trees of many ages are affected and a disease front can sometimes be detected. Pathogenicity tests show PTA is highly pathogenic to kauri. We propose that collar rot caused by PTA is an emerging disease caused by an introduced pathogen that is spreading slowly from widespread disease foci. It poses a threat to kauri, both at the individual icon level and at the population level, with flow-on effects to kauri ecosystems.

}, author = {Beever, JE and Coffey, MD and Ramsfield, TD and Dick, MA and Horner, IJ} } @article {doi:10.1094/PD-90-1362C, title = {First report of Phytophthora cambivora causing bleeding cankers and dieback on beech (Fagus sylvatica) in Italy}, journal = {Plant Disease}, volume = {90}, number = {10}, year = {2006}, pages = {1362-1362}, abstract = {

European beech (Fagus sylvatica) is an important forest tree species common in northern and central Europe. In Italy, this species is typical in mountain areas over 1,000 m above sea level. In the last decade, decline and death was reported on European beech caused by several Phytophthora species (2), and P. pseudosyringae was recently reported in Italy (3). During 2004 and 2005, seven declining and dying F. sylvatica trees, older than 20 years, were observed in the Veneto Region of Italy with symptoms of bleeding cankers at the base of trunks and on branches. Cankers on the collar showed tongue-shaped necroses of the inner bark and cambium tissues. Four trees were in a public park of Mestre and three were in a forest stand in the province of Belluno. Samples were taken from declining trees, one in the park and two in the forest. Inner bark and cambium tissue pieces were cut from the canker margins, cultured on CARPBHy-agar (corn meal agar amended with 250 μg ml-1 ampicillin, 10 μg ml-1 rifampicin, 10 μg ml-1 pimaricin, 15 μg ml-1 benomyl, 50 μg ml-1 hymexazol), and incubated at 20{\textdegree}C. Ten morphologically similar isolates were subcultured as single hyphal tips and characterized. These isolates produced nonpapillate sporangia that were ovoid, obpyriform or ellipsoid, and exhibited predominately internal proliferation in soil extract. Hyphal swellings with outgrowths were present under those conditions. The morphological characteristics were consistent with those of P. cambivora (1). Base sequences of the ITS region of rDNA were determined for six of the isolates, and an 832-bp fragment was amplified for each isolate and that sequence was 100\% homologous with sequences DQ396418 and AY880985 of P. cambivora in the NCBI database (http://www.ncbi.nlm.nih.gov/BLAST/). The sequence of one isolate, ISPaVe 1950, was deposited in GenBank (Accession No. AM269752). Pathogenicity tests were conducted with 2-year-old potted beech seedlings. Inoculum of representative isolates was grown for 4 weeks on sterilized millet seeds moistened with V8 broth and added to soil at 3\% (wt/vol). Control plants received sterilized inoculum only. The soil was flooded for 48 h. Inoculations were performed during May 2005 at 15 to 35{\textdegree}C with six replicates for the inoculated and control plants. The plants were maintained outdoors and assessed after 3 months. Wilt, root rot, and dark brown lesions at the collar developed on inoculated plants, but not on the controls. Symptoms were similar to those on naturally infected trees. The pathogen reisolated from the inoculated plants was morphologically identical to the original isolates, which confirmed P. cambivora as the causal agent. To our knowledge, this is the first report of P. cambivora on beech in Italy.

}, doi = {10.1094/PD-90-1362C}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PD-90-1362C}, author = {Belisario, A. and Maccaroni, M. and Vettorazzo, M.} } @article {4553, title = {Phytophthora gonapodyides Causes Decline and Death of English (Persian) Walnut ( Juglans regia) in Italy}, journal = {Plant Disease}, volume = {100}, year = {2016}, month = {Jan-12-2016}, pages = {2537 - 2537}, abstract = {

In late spring 2015, several commercially grown Persian walnut (Juglans regia L.) cv. Lara trees in northeastern Italy (Udine) exhibited extensive foliar wilt and canopy decline associated with collar and root rot. Sudden collapse was recorded in about 80\% of trees facing an irrigation canal. Symptomatic tissues excised from roots and collars of affected plants were surface disinfested for 1 min in a 1\% NaOCl solution, rinsed for 5 min in sterile distilled water, and placed onto P5ARPH selective medium. A Phytophthora-like organism was consistently isolated. Pure cultures, with a typical rosette pattern, were obtained by single-hyphal transfers onto potato dextrose agar (PDA). Mycelial disks of three isolates, AB260, AB261, and AB262, grown on carrot piece agar, were floated in petri plates with soil extract solution and incubated under continuous fluorescent light at room temperature. Within 48 to 72 h, sporangia were produced that were persistent, nonpapillate, tapered at the apex, and 40.0 to 102.8 {\texttimes} 22.8 to 45.7 {\textmu}m (average 56 {\texttimes} 33 {\textmu}m of 30 sporangia). Both internal and external proliferations were observed. Oospores and chlamydospores were absent. These morphological characteristics all corresponded to those reported for Phytophthora gonapodyides (Brasier et al. 1993; Erwin and Ribeiro 1996). Optimal growth for all three isolates was at 30{\textdegree}C (3.4 mm/day), with limited growth at 4{\textdegree}C (1.25 mm/day), and no growth at 35{\textdegree}C. The identity was confirmed by sequencing the internal transcribed spacer (ITS) using universal primers ITS4 and ITS6 (Cooke et al. 2000) and cytochrome c oxidase, subunit II (Cox II) (Martin and Tooley 2003). BLAST analysis of ITS 821-bp segment (GenBank accession nos. LN877760, LN901312, LN901313) showed 100\% identity with published P. gonapodyides sequences available in GenBank (i.e., HQ261570, AF541889, or AF541888), as well as with a Cox II 568-bp segment (LN877762, LN894191, LN894192) against AY129197. Greenhouse pathogenicity tests were conducted in controlled conditions. A total of six 1-year-old shoots cut from J. regia plants, about 2 cm in diameter, were used and three inoculation points each were made. Mycelial plugs (6 mm in diameter) cut from margins of actively growing 10-day-old cultures on PDA were inserted through the epidermis into phloem tissue. Controls were treated as described above except that sterile PDA plugs replaced the inoculum. Shoots were incubated in test tubes with sterile water in the dark at 24 {\textpm} 2{\textdegree}C. After 2 weeks, lesions were evident at all inoculation points, with an average length of 26 mm. Symptoms were similar to those caused by natural infection. P. gonapodyides was consistently reisolated from lesion margins. No colonies were isolated from control plants that remained symptomless. P. gonapodyides is ubiquitous in streams and ephemeral water pools, and is capable of saprophytic existence (Erwin and Ribeiro 1996). Although it is mainly known as a minor pathogen, there are reports indicating that some isolates can be highly virulent (Orlikowski et al. 2011) as in the present study where well developed 7-year-old walnut trees were killed by the pathogen. In the current study, P. gonapodyides aggressiveness was most likely sustained by the prolonged presence of flooding water at the root level, and a cool soil environment. To our knowledge, this is the first report of P. gonapodyides on Persian walnut in Italy or elsewhere.

}, issn = {0191-2917}, doi = {10.1094/PDIS-03-16-0394-PDN}, url = {http://apsjournals.apsnet.org/doi/10.1094/PDIS-03-16-0394-PDN}, author = {Belisario, A. and Luongo, L. and Vitale, S. and Galli, M. and Haegi, A.} } @article {4466, title = {Visualizing the early infection of Agathis australis by Phytophthora agathidicida, using microscopy and fluorescent in~situ hybridization}, journal = {Forest Pathology}, year = {2016}, month = {Jan-03-2016}, pages = {n/a - n/a}, abstract = {

Phytophthora agathidicida (PTA) causes a root rot and collar rot of New Zealand kauri (Agathis australis). This study developed techniques to visualize early infection of kauri by PTA in deliberately inoculated seedlings. Conventional light microscopy was carried out on cleared and stained roots using trypan blue to observe PTA structures. Additionally, scanning electron microscopy (SEM) was used to study the PTA root structures at a higher resolution. A fluorescent in\ situ hybridization assay (FISH) was developed using a PTA-specific probe to label PTA structures in planta. Infection progression in roots of 2-year-old kauri inoculated with PTA at 5, 10, 16 and 20\ days post-inoculation (d.p.i.) was compared using these three approaches. Light microscopy identified no Phytophthora-like structures in the control treatments. In PTA-inoculated plants, lignitubers were produced 5\ d.p.i. in cortical cells. Infection was localized after 5\ days, but as the infection progressed (up to 20\ d.p.i.), the {\textquoteleft}degree{\textquoteright} of root infection increased, as did the number of replicates in which structures were observed. SEM provided higher resolution images; again, no PTA structures were observed in the negative control material examined. The slide-based FISH-specificity assay successfully hybridized with PTA hyphae. Fluorescence was observed using 330{\textendash}380\ nm excitation and an emission filter at 420\ nm (DAPI), with PTA nuclei fluorescing a bright greenish-yellow. Cross-reactivity was not observed when the assay was applied to six other non-target Phytophthora species. Successful hybridization reactions occurred between the primer and PTA structures in planta. Applying this FISH assay has allowed clear differentiation of the intracellular and intercellular structures of PTA. The technique can be applied to longer term studies or analysis of ex situ inoculation studies aiming to elucidate differential host-responses to the pathogen. Additionally, the technique could be applied to study the interactions with other fungal endophytes (e.g. mycorrhizal fungi), which could be assessed for biocontrol potential as part of the integrated management of the disease.

}, doi = {10.1111/efp.12280}, url = {http://doi.wiley.com/10.1111/efp.12280}, author = {Bellgard, S. E. and Padamsee, M. and Probst, C. M. and Lebel, T. and Williams, S. E.}, editor = {Jung, T.} } @article {doi:10.1094/PDIS.2000.84.6.661, title = {Incidence of Phytophthora root rot of Fraser fir in North Carolina and sensitivity of isolates of Phytophthora cinnamomi to metalaxyl}, journal = {Plant Disease}, volume = {84}, number = {6}, year = {2000}, pages = {661-664}, doi = {10.1094/PDIS.2000.84.6.661}, url = {http://apsjournals.apsnet.org/doi/abs/10.1094/PDIS.2000.84.6.661}, author = {Benson, D. M. and Grand, L. F.} } @book {3946, title = {A range-wide assessment of Port-Orford-Cedar (Chamaecyparis lawsoniana) on federal lands}, year = {2003}, pages = {182}, publisher = { U.S. Department of Agriculture, Forest Service, and U.S. Department of the Interior, Bureau of Land Management}, organization = { U.S. Department of Agriculture, Forest Service, and U.S. Department of the Interior, Bureau of Land Management}, address = {Portland, OR}, url = {http://www.fs.fed.us/r6/dorena/publications/in/poc-range-wide-assessment}, author = {Betlejewski, F. and Casavan, K. and Dawson, A. and Goheen, D.G. and Mastrofini, K. and Rose, D.L. and White, D.E.} } @article {4720, title = {Phytophthora spp. associated with Appalachian oak forests and waterways in Pennsylvania, with P. abietivora as a pathogen of five native woody plant species.}, journal = {Plant Disease}, year = {2021}, month = {11/2021}, abstract = {

To document the distribution of potentially harmful Phytophthora spp. within Pennsylvania (PA), the PA Department of Agriculture collected 89 plant, 137 soil, and 48 water samples at 64 forested sites from 2018 to 2020. In total, 231 Phytophthora strains were isolated using baiting assays and identified based on morphological characteristics and sequences of nuclear and mitochondrial loci. Twenty-one Phytophthora spp. in nine clades and one unidentified species were present. Phytophthora abietivora, a recently described clade 7a species, was recovered from diseased tissue of 10 native broadleaved plants and twice from soil from 12 locations. Phytophthora abietivora is most likely endemic to PA based on pathogenicity tests on six native plant species, intraspecific genetic diversity, wide distribution, and recoveries from Abies Mill. and Tsuga Carri{\`e}re plantations dating back to 1989. Cardinal temperatures and morphological traits are provided for this species. Other taxa, in decreasing order of frequency, include P. chlamydospora, P. plurivora, P. pini, P. cinnamomi, P. xcambivora, P. irrigata, P. gonapodyides, P. cactorum, P. pseudosyringae, P. hydropathica, P. stricta, P. xstagnum, P. caryae, P. intercalaris, Phytophthora {\textquoteleft}bitahaiensis{\textquoteright}, P. heveae, P. citrophthora, P. macilentosa, P. cryptogea, and P. riparia. Twelve species were associated with diseased plant tissues. This survey documented 53 new plant-Phytophthora associations and expanded the known distribution of some species.

}, issn = {0191-2917}, doi = {10.1094/PDIS-05-21-0976-RE}, url = {https://apsjournals.apsnet.org/doi/10.1094/PDIS-05-21-0976-RE}, author = {Bily, Devin and Nikolaeva, Ekaterina V. and Olson, Tracey and Kang, Seogchan} } @article {Blackwell194371, title = {The life history of Phytophthora cactorum (Leb. \& Cohn) Schroet}, journal = {Transactions of the British Mycological Society}, volume = {26}, number = {1-2}, year = {1943}, pages = {71 - 89}, abstract = {Summary An account is given of the life history of Phytophthora Cactorum (Leb. \& Cohn) Schroet., a paragynous, homothallic species. The mycelium and reproductive spores in their development and germination are described as under: The mycelium: its vegetative growth and form and its perennation. The sporangium, conidium, resting conidium, chlamydospore: their interrelationships, development and germination. The oogonium and antheridium: fertilization. The oospore: its dormancy and germination.}, issn = {0007-1536}, doi = {DOI: 10.1016/S0007-1536(43)80013-9}, url = {http://www.sciencedirect.com/science/article/B985G-4YW2HHM-D/2/d8cd209743ea7bb728b94dadd761bd5d}, author = {Elizabeth Blackwell} } @article {Blaha19941379, title = {Phytophthora isolates from coconut plantations in Indonesia and Ivory Coast: characterization and identification by morphology and isozyme analysis}, journal = {Mycological Research}, volume = {98}, number = {12}, year = {1994}, pages = {1379 - 1389}, abstract = {

Isolates of Phytophthora were obtained from coconut palms with bud rot and/or premature nut-fall disease in Indonesia (36 isolates) and Ivory Cost (15 isolates), and from coconut plantation soil in Indonesia (17 isolates). Their morphology and isozyme patterns for MDH and GPI were compared with those of seven known Phytophthora species. Isolates from Indonesia assigned to P. arecae or P. palmivora by morphology had identical isozyme patterns and could not be separated by cluster analysis. Isolates of P. palmivora had one single-banded, and three triple-banded GPI patterns, one of which was unique to isolates from coconut. Isolates from Ivory Coast were assigned by morphology and by a distinctive MDH isozyme pattern to P. katsurae. They showed some morphological similarities, and had an identical GPI isozyme pattern to reference cultures of P. heveae, previously reported as a pathogen on coconut. We conclude that P. palmivora is the main pathogen associated with bud rot and premature nut-fall in Indonesia, whereas P. katsurae is associated with premature nut-fall in Ivory Coast.

}, issn = {0953-7562}, doi = {DOI: 10.1016/S0953-7562(09)81067-8}, url = {http://www.sciencedirect.com/science/article/pii/S0953756209810678}, author = {Georges Blaha and Geoffrey Hall and Jeffry S. Warokka and Erlene Concibido and Carlos Ortiz-Garcia} } @article {Blair2008266, title = {A multi-locus phylogeny for Phytophthora utilizing markers derived from complete genome sequences}, journal = {Fungal Genetics and Biology}, volume = {45}, number = {3}, year = {2008}, pages = {266 - 277}, keywords = {Molecular markers}, issn = {1087-1845}, doi = {DOI: 10.1016/j.fgb.2007.10.010}, url = {http://www.sciencedirect.com/science/article/B6WFV-4PYP77J-1/2/ebf8754b49bc2fd36ab9e34941eeed43}, author = {Jaime E. Blair and Michael D. Coffey and Sook-Young Park and David M. Geiser and Seogchan Kang} } @article {4449, title = {Detection of Phytophthora ramorum in Nurseries and Forest Lands in California in 2004 to 2009}, journal = {Plant Disease}, volume = {100}, year = {2016}, month = {Jan-01-2016}, pages = {139 - 148}, abstract = {

From December 2004 through May 2009, samples were collected from California nurseries and wild lands to survey for Phytophthora ramorum and comply with federal regulations of nursery stock. Samples were prescreened by an enzyme-linked immunosorbent assay (ELISA) that detects Phytophthora spp. and tested by culture, P. ramorum-specific real-time polymerase chain reaction (PCR), and nested PCR. Yearly percentages of infected samples ranged from 0.6 to 2.3\%. Camellia spp., Rhododendron spp., Magnolia spp., Pieris spp., and Laurus nobilis tested positive the most frequently in the nurseries and Lithocarpus densiflorus, Umbellularia californica, and Quercus agrifolia tested positive most often from wild lands. Of the 118,410 samples isolated onto PARP media, 0.8\% was identified as P. ramorum. Of 115,056 samples tested by ELISA, 5.9\% tested positive for Phytophthora spp. Of the 6,520 samples tested by PCR, 12.4\% tested positive for P. ramorum. The false-negative, positive, and internal control failure rates of the assays are discussed. After removing the seasonal effect of sampling strategy, isolation of the pathogen into culture was found to be seasonally dependent whereas detectability by PCR and ELISA was not. To our knowledge, this is the first evaluation of a regulatory testing program for a plant pathogen on this scale using standardized assays.

}, issn = {0191-2917}, doi = {10.1094/PDIS-12-14-1302-RE}, url = {http://apsjournals.apsnet.org/doi/10.1094/PDIS-12-14-1302-RE}, author = {Blomquist, C. L. and Yakabe, L. E. and Rooney-Latham, S. and McRoberts, N. and Thomas, C.} } @article {4651, title = {First Report of Leaf Spot Caused by Phytophthora taxon Pgchlamydo on Evergreen Nursery Stock in California}, journal = {Plant Disease}, volume = {96}, year = {2012}, month = {Jan-11-2012}, pages = {1691 - 1691}, abstract = {

As part of the Phytophthora ramorum testing program from 2005 through 2007, a Phytophthora sp. was isolated on PARP-CMA medium (4) at the CDFA lab in Sacramento, CA, from the margin of necrotic spots and tissue suffering from dieback on Arctostaphylos sp. (manzanita), Camellia spp., Laurus nobilis (bay), Buxus sempervirens (boxwood), Rhododendron sp., Arbutus unedo (strawberry tree), and Sequoia sempervirens (coast redwood). Isolates were collected from Shasta, Contra Costa, San Diego, Solano, Santa Cruz, Alameda, Sacramento, San Joaquin, Monterey, and Los Angeles Counties. Isolates from A. unedo tissue on PARP medium produced apapillate, obovate sporangia 25 to 80 {\texttimes} 15 to 40 μm (48.0 {\texttimes} 26.9 μm average) and a few isolates produced intercalary and terminal chlamydospores at 22{\textdegree}C (30 to 46 μm diameter, 38.9 μm average). The internal transcribed spacer region (ITS) of rDNA was amplified from four isolates using ITS1 and ITS4 primers as described by White et al. (3) and the amplicons sequenced (GenBank Accession Nos. JQ307188 through JQ307191). BLAST analysis of the amplicons showed 99 to 100\% identity with the ITS sequence of Phytophthora taxon Pgchlamydo from forest streams in Oregon (GenBank Accession No. HM004224) (1). Pathogenicity tests were performed on B. sempervirens, C. sasanqua, L. nobilis, and A. unedo. Five plants of each species were inoculated with 6-mm plugs taken from the margin of a 7- to 10-day-old culture grown on V8 juice agar. Plant leaves were wounded with a sterile pushpin and two agar plugs were covered with a freezer tube cap filled with sterile dH2O and clipped to the underside of the leaves with a sterile pin-curl clip (4). Inoculated plants were sprayed with water, covered with plastic bags, and incubated for 2 days, when bags and plugs were removed. Five leaves of each isolate plus five control plugs using V8 juice agar alone were inoculated on each plant. Plants were incubated for 12 days at 18{\textdegree}C (16-h photoperiod). Lesions formed on all inoculated plants, ranging in size from approx. 1 mm on B. sempervirens to 9.2 {\texttimes} 10.9 mm average on A. unedo. The lesions on A. unedo grew into and caused the mid-vein to blacken. The lesion sizes on camellia and bay were larger than those formed on B. sempervirens and smaller than those formed on A. unedo, with most lesions surrounded by a dark ring. Phytophthora taxon Pgchlamydo is associated with leaf lesions on rhododendron and dieback of yew in Minnesota (2). To our knowledge, this is the first report of Phytophthora taxon Pgchlamydo causing disease in camellia, bay, strawberry tree, and boxwood in California. Phytophthora taxon Pgchlamydo causes damage that is indistinguishable from the quarantine pest, P. ramorum (4).

References: (1) P. W. Reeser et al. Mycologia 103:22, 2011. (2) B. W. Schwingle and R. A. Blanchette. Plant Dis. 92:642, 2008. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds., Academic Press, San Diego, 1990. (4) L. E. Yakabe et al. Plant Dis. 93:883, 2009.

}, issn = {0191-2917}, doi = {10.1094/PDIS-02-12-0221-PDN}, url = {http://apsjournals.apsnet.org/doi/10.1094/PDIS-02-12-0221-PDN}, author = {Blomquist, C. L. and Yakabe, L. E. and Soriano, M. C. and Negrete, M. A.} } @article {4123, title = {The impact of plant diseases on world chocolate production}, journal = {Plant Health Progress}, year = {2001}, abstract = {

Many factors contribute to a decline in production of cocoa beans worldwide. Plant diseases such as black pod, witches{\textquoteright} broom, and frosty pod rot are major components of the decline in production. Plant pathologists and microbiologists must discover and devise means to reduce disease losses and to save chocolate for the enthusiastic consumers of the world. This review discusses the major disease of cacao and their effect on world production.

}, doi = {10.1094/PHP-2001-0709-01-RV}, url = {http://www.plantmanagementnetwork.org/pub/php/review/cacao/}, author = {Bowers, J. H. and Bailey, B. A. and Hebbar, P. K. and Sanogo, S. and Lumsden, R. D.} } @article {4680, title = {Phytophthora agathidicida: research progress, cultural perspectives and knowledge gaps in the control and management of kauri dieback in New Zealand}, journal = {Plant Pathology}, volume = {69}, year = {2020}, month = {Feb-01-2021}, pages = {3 - 16}, abstract = {

Kauri (Agathis australis), which is one of the world{\textquoteright}s largest and longest-living conifer species, is under threat from a root and collar dieback disease caused by the oomycete pathogen Phytophthora agathidicida. The noted incidence of kauri dieback has increased in the past decade, and even trees \>1000\ years old are not immune. This disease has profound effects on both forest ecosystems and human society, particularly indigenous M{\={a}}ori, for whom kauri is a taonga or treasure of immense significance. This review brings together existing scientific knowledge about the pathogen and the devastating disease it causes, as well as highlighting important knowledge gaps and potential approaches for disease management. The life cycle of P.\ agathidicida is similar to those of other soilborne Phytophthora pathogens, with roles for vegetative hyphae, zoospores and oospores in the disease. However, there is comparatively little known about many aspects of the biology of P.\ agathidicida, such as its host range and disease latency, or about the impact on the disease of abiotic and biotic factors such as soil health and co-occurring Phytophthora species. This review discusses current and emerging tools and strategies for surveillance, diagnostics and management, including a consideration of genomic resources, and the role these play in understanding the pathogen and how it causes this deadly disease. Key aspects of indigenous M{\={a}}ori knowledge, which include rich ecological and historical knowledge of kauri forests and a holistic approach to forest health, are highlighted.

}, issn = {0032-0862}, doi = {10.1111/ppa.v69.110.1111/ppa.13104}, url = {https://bsppjournals.onlinelibrary.wiley.com/doi/full/10.1111/ppa.13104}, author = {Bradshaw, R. E. and Bellgard, S. E. and Black, A. and Burns, B. R. and Gerth, M. L. and McDougal, R. L. and Scott, P. M. and Waipara, N. W. and Weir, B. S. and Williams, N. M. and Winkworth, R. C. and Ashcroft, T. and Bradley, E. L. and Dijkwel, P. P. and Guo, Y. and Lacey, R. F. and Mesarich, C. H. and Panda, P. and Horner, I. J.} } @proceedings {607, title = {A disease survey of cherimoya orchards in Northland, New Zealand.}, year = {2007}, address = {Adelaide}, author = {Braithwaite, M. and Bullians, M.S. and Pay, J.M. and Gill, G.S.C. and Hill, C.F.} } @article {4612, title = {Genetic diversity of Phytophthora pluvialis, a pathogen of conifers, in New Zealand and the west coast of the United States of America}, journal = {Plant Pathology}, volume = {67}, year = {2018}, month = {Jan-06-2018}, pages = {1131 - 1139}, abstract = {

Phytophthora pluvialis is the causal agent of red needle cast on Pinus radiata in New Zealand. It was first isolated in 2008 but had previously been recovered from tanoak (Notholithocarpus densiflorus) and Douglas-fir (Pseudotsuga menziesii) trees in Oregon, USA in 2002. Phytophthora pluvialis was subsequently described as a new species in 2013 and classified as a clade III Phytophthora species. The aim of this study was to gain a better understanding of the genetic diversity, population structure and origin of this pathogen. A total of 360 P.\ pluvialis isolates were collected from the USA and New Zealand. The genome sequences of two P.\ pluvialis isolates were used to identify 27 single nucleotide polymorphism (SNP) markers that were then used to genotype the two populations. The genotypic data showed that the USA population of P.\ pluvialis had twice the genetic diversity and a greater number of multilocus genotypes (MLGs) compared to the New Zealand population, with 126 and 24 MLGs, respectively. The majority of the subpopulations within the USA and New Zealand showed linkage disequilibrium. All subpopulations had a negative fixation index, indicating that clonal reproduction is prevalent in both countries. A minimum spanning network (MSN) showed two unique clusters of isolates in the New Zealand population, suggesting two potential introductions of P.\ pluvialis into New Zealand from the USA. There was no significant structure within the New Zealand or USA populations. This study provides novel insight into the genetic structure of P.\ pluvialis in New Zealand and the USA.

}, doi = {https://doi.org/10.1111/ppa.12812}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/ppa.12812?campaign=wolacceptedarticle}, author = {Brar, S. and Tabima, J. F. and McDougal, R. L. and Dupont, P.-Y. and Feau, N. and Hamelin, R. C. and Panda, P. and LeBoldus, J. M. and Gr{\"u}nwald, N. J. and Hansen, E. M. and Bradshaw, R. E. and Williams, N. M.} } @article {588, title = {Plant pathology: Sudden larch death}, journal = {Nature}, volume = {466}, year = {2010}, pages = {824-825}, chapter = {824}, doi = {10.1038/466824a}, url = {http://dx.doi.org/10.1038/466824a}, author = {Brasier,Clive and Webber,Joan} } @article {268, title = {Oak mortality in Iberia}, journal = {Nature}, volume = {360}, year = {1992}, pages = {539-539}, issn = {0028-0836}, doi = {doi:10.1038/360539a0}, url = {http://www.nature.com/nature/journal/v360/n6404/abs/360539a0.html}, author = {C.M. Brasier} } @article {CambridgeJournals:150657, title = {Sudden Oak Death: Phytophthora ramorum exhibits transatlantic differences}, journal = {Mycological Research}, volume = {107}, number = {03}, year = {2003}, pages = {257-259}, doi = {10.1017/S0953756203227660}, url = {http://dx.doi.org/10.1017/S0953756203227660}, author = {Brasier,Clive} } @article {594531620010401, title = {Comparative aggressiveness of standard and variant hybrid alder phytophthoras, Phytophthora cambivora and other phytophthora species on bark of alnus, Quercus and other woody hosts.}, journal = {Plant Pathology}, volume = {50}, number = {2}, year = {2001}, pages = {218}, abstract = {

Analyzes results of pathogenicity tests on the bark of Alnus glutinosa with standard and variant hybrid alder phytophthoras. Aggressiveness on living alder logs; Levels of pathogenicity; Rates of lesion development.

}, keywords = {Alnus glutinosa, Disease, pest resistance, Phytophthora, plants}, issn = {00320862}, doi = {10.1046/j.1365-3059.2001.00553.x}, url = {http://onlinelibrary.wiley.com.proxy.library.oregonstate.edu/doi/10.1046/j.1365-3059.2001.00553.x/abstract}, author = {C.M. Brasier and Kirk, S.A.} } @article {PPA:PPA140, title = {Evidence for Phytophthora cinnamomi involvement in Iberian oak decline}, journal = {Plant Pathology}, volume = {42}, number = {1}, year = {1993}, pages = {140{\textendash}145}, publisher = {Blackwell Publishing Ltd}, abstract = {

Rapid and sometimes extensive mortality and decline of oak, principally Quercus suber and Q. ilex, has occurred in parts of southern Spain and Portugal in recent decades. We report here isolation of the aggressive root pathogen Phytophthora cinnamomi from roots of diseased oaks or from soil at eleven out of thirteen decline foci examined. It is proposed that the introduction and spread of P. cinnamomi may be a major factor in the Iberian oak decline, interacting with drought and other site factors, and leading to stress-related attacks by insects and other fungi. By analogy, it may also be involved in the similar oak declines occurring elsewhere on the Mediterranean.

}, issn = {1365-3059}, doi = {10.1111/j.1365-3059.1993.tb01482.x}, url = {http://dx.doi.org/10.1111/j.1365-3059.1993.tb01482.x}, author = {C.M. Brasier and Robredo, F. and Ferraz, J. F. P.} } @article {Brasier2012, title = {Four phenotypically and phylogenetically distinct lineages in Phytophthora lateralis}, journal = {Fungal Biology}, year = {2012}, pages = {-}, abstract = {

Until recently Phytophthora lateralis was known only as the cause of dieback and mortality of Chamaecyparis lawsoniana in its native range in the Pacific Northwest. Since the 1990s however disease outbreaks have occurred increasingly on ornamental C. lawsoniana in Europe; and in 2007 the pathogen was discovered in soil around old growth C. obtusa in Taiwan, where it may be endemic. When the phenotypes of over 150 isolates of P. lateralis from Taiwan, across the Pacific Northwest (British Columbia to California) and from France, the Netherlands and the UK were compared three growth rate groups were resolved: one slow growing from Taiwan, one fast growing from the Pacific Northwest and Europe and one of intermediate growth from a small area of the UK. Within these growth groups distinct subtypes were identified based on colony patterns and spore metrics and further discriminated in a multivariate analysis. The assumption that the three main growth groups represented phylogenetic units was tested by comparative sequencing of two mitochondrial and three nuclear genes. This assumption was confirmed. In addition two phenotype clusters within the Taiwan growth group were also shown to be phylogenetically distinct. These four phenotypically and genotypically unique populations are informally designated as the Pacific Northwest lineage, the UK lineage, the Taiwan J lineage and the Taiwan K lineage. Their characteristics and distribution are described and their evolution, taxonomic and plant health significance is discussed.

}, keywords = {Colony pattern, evolution, Growth rate, Multigene phylogeny, Multivariate analysis, Sporangial morphology}, issn = {1878-6146}, doi = {10.1016/j.funbio.2012.10.002}, url = {http://www.sciencedirect.com/science/article/pii/S1878614612001717?v=s5}, author = {Clive M. Brasier and Selma Franceschini and Vettraino, Anna Maria and Hansen, Everett M. and Sarah Green and Cecile Robin and Joan F. Webber and Andrea Vannini} } @article {Brasier11051999, title = {Origin of a new Phytophthora pathogen through interspecific hybridization}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {96}, number = {10}, year = {1999}, pages = {5878-5883}, abstract = {Plant disease epidemics resulting from introductions of exotic fungal plant pathogens are a well known phenomenon. An associated risk that accelerated pathogen evolution may be occurring as a consequence of genetic exchange between introduced, or introduced and resident, fungal pathogens is largely unrecognized. This is, in part, because examples of natural, interspecific hybridization in fungi are very rare. Potential evolutionary developments range from the acquisition of new host specificities to emergence of entirely new pathogen taxa. We present evidence from cytological behavior, additive nucleotide bases in repetitive internal transcribed spacer regions of the rRNA-encoding DNA (rDNA), and amplified fragment length polymorphisms of total DNA that a new, aggressive Phytophthora pathogen of alder trees in Europe comprises a range of heteroploid-interspecific hybrids involving a Phytophthora cambivora-like species and an unknown taxon similar to Phytophthora fragariae. The hybrids marked developmental instabilities, unusual morphological variability, and evidence for recombination in their internal transcribed spacer profiles indicates that they are of recent origin and that their evolution is continuing. The likelihood of such evolutionary events may be increasing as world trade in plants intensifies. However, routine diagnostic procedures currently in use are insufficiently sensitive to allow their detection.}, doi = {doi: 10.1073/pnas.96.10.5878}, url = {http://www.pnas.org/content/96/10/5878.abstract}, author = {C.M. Brasier and Cooke, D. E. L. and Duncan, J. M.} } @article {Brasier19931287, title = {Cultural characters, protein patterns and unusual mating behaviour of Phytophthora gonapodyides isolates from Britain and North America}, journal = {Mycological Research}, volume = {97}, number = {11}, year = {1993}, pages = {1287 - 1298}, issn = {0953-7562}, doi = {DOI: 10.1016/S0953-7562(09)80160-3}, url = {http://www.sciencedirect.com/science/article/B7XMR-4VXMWBV-2/2/79f23cf89ac836528cb576d2f46f81b3}, author = {C.M. Brasier and P.B. Hamm and Hansen, E.M.} } @article {1261, title = {Natural stem infection of Lawson cypress (Chamaecyparis lawsoniana) caused by Phytophthora ramorum}, journal = {New Disease Reports}, volume = {25}, year = {2012}, pages = {26}, url = {http://dx.doi.org/10.5197/j.2044-0588.2012.025.026}, author = {C.M. Brasier and Webber, JF} } @article {1439572819951201, title = {An unusual Phytophthora associated with widespread alder mortality in Britain}, journal = {Plant Pathology}, volume = {44}, number = {6}, year = {1995}, pages = {999 - 1007}, abstract = {

During 1993 and 1994 an unusual Phytophthora was consistently isolated from bark lesions at the stem bases of dying alder in Southern Britain. The Phytophthora resembles P. cambivora in both its gametangial and sporangial morphology. However, it is distinct from this species in being homothallic rather than outcrossing; in producing a significant proportion of small and sometimes partially developed oogonia; in having a high frequency of oosphere abortion; in having an appressed felty colony type with little or no aerial mycelium; and in exhibiting a lower optimum temperature for growth (c.22.5{\textdegree}C) and lower growth temperature maximum (c.29{\textdegree}C) on carrot agar than P. cambivora (c.27.5{\textdegree} and 33.5{\textdegree}C respectively). An inoculation test confirmed its pathogenicity to Alnus. The status of the alder Phytophthora is discussed. On the basis of its unusual characteristics and unusual host it is suggested that it might be a new or recently introduced organism rather than a previously unrecorded indigenous variant of P. cambivora.

}, keywords = {AGRICULTURAL pests, ALDER, ALDER {\textendash} Diseases \& pests, GREAT Britain, Phytophthora, PLANT diseases}, issn = {00320862}, doi = {doi/10.1111/j.1365-3059.1995.tb02658.x}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3059.1995.tb02658.x/abstract}, author = {C.M. Brasier and Rose, J. and Gibbs, J. N.} } @article {4653, title = {Multiple new phenotypic taxa from trees and riparian ecosystems in Phytophthora gonapodyides-P. megasperma ITS Clade 6, which tend to be high-temperature tolerant and either inbreeding or sterile}, journal = {Mycological Research}, volume = {107}, year = {2003}, month = {Jan-03-2003}, pages = {277 - 290}, abstract = {

Phytophthora isolates associated with Phytophthora major ITS Clade 6 were grouped into 11 phenotypic taxa. These comprised the described morphospecies P. gonapodyides, P. megasperma s. str. and P. humicola; four previously identified but so far undescribed taxa, informally designated here P. sp. O-group, P. sp. Apple-cherry, P. taxon Pgchlamydo, and P. taxon Walnut; and four previously unknown taxa, designated P. taxon Oaksoil, P. taxon Raspberry, P. taxon Forestsoil, and P. taxon Riversoil. With the exception of P. gonapodyides each phenotypic taxon represented an unique ITS lineage. Two isolates morphologically identical to P. gonapodyides comprised a separate lineage and probably represent another taxon, designated here P. taxon Salixsoil. P. humicola, P. sp. O-group, P. sp. Apple-cherry and P. taxon Walnut grouped together as subclade I. Within subclade II, P. taxon Oaksoil, P. taxon Raspberry, P. taxon Forestsoil, P. taxon Riversoil and P. taxon Pgchlamydo formed a cluster of closely related but phenotypically distinct lineages basal to P. gonapodyides and P. megasperma, P. taxon Salixsoil being the most basal member. The taxonomy, adaptation and breeding systems of Clade 6 taxa are discussed. They show a strong association with forests and riparian ecosystems, only a limited association with agriculture and an ability to tolerate high temperatures. Also, in contrast to most other Phytophthora clades, Clade 6 taxa are predominantly sterile or inbreeding in culture. Only one taxon, P. sp. O-group, appears classically A1/A2 heterothallic.

}, issn = {09537562}, doi = {10.1017/S095375620300738X}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0953756208611788}, author = {Brasier, Clive M. and Cooke, David E.L. and Duncan, James M. and Hansen, Everett M.} } @article {CambridgeJournals:249527, title = {Sudden oak death (Phytophthora ramorum) discovered on trees in Europe}, journal = {Mycological Research}, volume = {108}, number = {10}, year = {2004}, pages = {1108-1110}, doi = {10.1017/S0953756204221244}, url = {http://dx.doi.org/10.1017/S0953756204221244}, author = {Brasier,Clive and Denman,Sandra and Brown,Anna and Webber,Joan} } @article {Brasier2004823, title = {Production of gametangia by Phytophthora ramorum in vitro}, journal = {Mycological Research}, volume = {108}, number = {7}, year = {2004}, pages = {823 - 827}, abstract = {

Until now gametangia have not been obtained between paired European A1 and American A2 isolates of Phytopthora ramorum in vitro. Their production in artificial culture relies on interspecific pairings. Using P. drechsleri and P. cambivora testers, 51 of 110 P. ramorum isolates from across Europe were all shown to be A1s; while 32 of 38 American isolates from across California and southwest Oregon were shown to be A2s. However, these interspecific pairings are complex, unusually slow and unpredictable. A range of culture media and conditions are described that were tested, unsuccessfully, with a view to enhancing the efficiency of the interspecific pairings. In further tests, gametangia were obtained between A1 and A2 isolates of P. ramorum when juvenile, pre-chlamydospore producing mycelia were mixed together on carrot agar. The gametangia formed in 3{\textendash}10 d, sparsely to frequently, initially only within the boundaries of the mixed inocula but subsequently in the extended mycelial growth. Chlamydospores were also produced. This inoculum-mixing method, though again sometimes unpredictable, should enhance efficiency of testing for compatibility types and facilitate further studies on whether the sexual outcrossing system of P. ramorum is functional. Differences between sexual reproduction of P. ramorum and that of other heterothallic Phytophthora species are discussed.

}, issn = {0953-7562}, doi = {10.1017/S0953756204000565}, url = {http://www.sciencedirect.com/science/article/pii/S0953756208603949}, author = {Brasier,Clive and Susan Kirk} } @article {CambridgeJournals:249519, title = {Phytophthora alni sp. nov. and its variants: designation of emerging heteroploid hybrid pathogens spreading on Alnus trees}, journal = {Mycological Research}, volume = {108}, number = {10}, year = {2004}, pages = {1172-1184}, abstract = {

In 1993 a destructive new Phytophthora pathogen of riparian Alnus trees was discovered in the UK and subsequently shown to be present in other parts of Europe. The new Phytophthora comprised a group of emergent heteroploid hybrids, probably between P. cambivora and a species related to P. fragariae. These included a common, near tetraploid standard hybrid, the presumptive allopolyploid; and four scarcer major variant types with chromosome numbers intermediate between diploid and tetraploid, named the Swedish, Dutch, German and UK variants. The standard hybrid type is formally designated here as Phytophthora alni subsp. alni. The Swedish variant is designated as P. alni subsp. uniformis; and the Dutch, German and UK variants collectively as P. alni subsp. multiformis. The properties of the Dutch, German and UK variants within subsp. multiformis are informally described. The problems of designating emergent species hybrids under the International Code of Botanical Nomenclature and the reasons for the taxonomic choices made are discussed.

}, doi = {10.1017/S0953756204001005}, url = {http://dx.doi.org/10.1017/S0953756204001005}, author = {Clive M. Brasier and Kirk, S.A. and Jose Delcan and David E.L. Cooke and Thomas Jung and Man In{\textquoteright}t Veld, W.A.} } @article {Brasier2003277, title = {Multiple new phenotypic taxa from trees and riparian ecosystems in Phytophthora gonapodyides-P. megasperma ITS Clade 6, which tend to be high-temperature tolerant and either inbreeding or sterile}, journal = {Mycological Research}, volume = {107}, number = {3}, year = {2003}, pages = {277 - 290}, issn = {0953-7562}, doi = {DOI: 10.1017/S095375620300738X}, url = {http://www.sciencedirect.com/science/article/B7XMR-4RT04VN-6/2/68f2582c518f07f52e7a0db891ca14dd}, author = {Clive M. Brasier and David E.L. Cooke and James M. Duncan and Hansen, Everett M.} } @article {4652, title = {Cultural characters, protein patterns and unusual mating behaviour of Phytophthora gonapodyides isolates from Britain and North America}, journal = {Mycological Research}, volume = {97}, year = {1993}, month = {Jan-11-1993}, pages = {1287 - 1298}, abstract = {

Isolates of Phytophthora gonapodyides associated with roots of woody hosts or from aquatic habitats in Britain (10 isolates) and North America (Alaska to California, 12 isolates) were compared. They showed similar characteristics including similar sporangial dimensions, colonies with often distinctive petaloid patterns and a silvery appearance, slow growth rates at 20, 25 and 30 {\textdegree}C, and a maximum temperature for growth of about 35{\textdegree}. Most isolates exhibited a similar protein banding pattern distinct from that of P. cryptogea or P. drechsleri, and including a characteristic band designated the {\textquoteleft}PG band{\textquoteright}. Three isolates deviated from this pattern and two of these also produced chlamydospores and chains of swellings in culture. These isolates might be hybrids related to P. gonapodyides or a different taxon, in which case {\textquoteleft}P. gonapodyides{\textquoteright} is polyphyletic.

All the isolates were self-sterile. When paired directly or indirectly via polycarbonate membranes with A2 sexual compatibility types of heterothallic species such as P. cambivora, P. megakarya or P. meadii, gametangia were produced which were morphologically characteristic of these species. The range of heterothallic species responding was different from that responding sexually to Trichoderma volatiles. P. gonapodyides isolates may be sterile A1 compatibility types able to produce a compatibility substance which induces selfing in the heterothallic A2s.

Three other self-sterile Phytophthora isolates associated with woody hosts in Britain were a distinct group, with a different colony pattern, a distinct 30{\textdegree} growth optimum and an ability to grow at 37{\textdegree}. Their protein banding pattern was different from that of either P. gonapodyides or P. cryptogea/P. drechsleri, but showed similarities to these species. One isolate induced gametangial formation in P. drechsleri A1 types, the two others were sexually neutral. These three isolates might also be species hybrids, possibly with P. gonapodyides and P. cryptogea as parents.

}, issn = {09537562}, doi = {10.1016/S0953-7562(09)80160-3}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0953756209801603}, author = {Brasier, C.M. and Hamm, P.B. and Hansen, E.M.} } @article {4135, title = {Taxonomy of Phytophthora palmivora on cocoa}, journal = {Transactions of the British Mycological Society}, volume = {72}, year = {1979}, month = {2/1979}, pages = {111 - 143}, abstract = {

Morphological and physiological studies-chromosome type, colony morphology and growth rate on carrot agar, cocoa pod lesion characteristics, morphology and size of sporangia, sporangial pedicels, chlamydospores and sex organs, compatibility type, growth on a synthetic medium, response to Trichoderma, and temperature relations-were made with c. 950 Phytophthora isolates from cocoa (Theobroma cacao L.) attributed to P. palmivora (Butl.) Butl. The survey covered isolates from all the major cocoa growing areas of the world, and included isolates studied by C. H. Gadd and S. F. Ashby in the 1920s.

The majority of the isolates could be assigned to one of three distinct forms, termed S, L and MF4. The S-type is attributed here to P. palmivora, which is redefined. Both L and MF4 are considered to be distinct species of Phytophthora. The L-type could not be identified with any known species and is described here as P. megakarya sp.nov. P. palmivora occurred world-wide on cocoa, whereas P. megakarya was obtained only from West Africa and MF4 only from Central and South America and the West Indies.

Isolates attributed to P. palmivora from other hosts were also examined. Some isolates from rubber, coconut and durian were P. palmivora (S-type). Isolates from pepper comprised a group closely resembling MF4. Isolates from coconut and rubber originally attributed to P. palmivora by S. F. Ashby, C. H. Gadd and E. M. Blackwell comprised a further group, and were also attributed here to P. palmivora, yet were somewhat different morphologically from the S-type on cocoa. It is not clear which of these two types is authentic P. palmivora.

The significance of these results, and the value of the various diagnostic criteria used, is discussed.

}, issn = {00071536}, doi = {10.1016/S0007-1536(79)80015-7}, url = {http://www.sciencedirect.com/science/article/pii/S0007153679800157}, author = {C.M. Brasier and Griffin, M.J.} } @article { refId, title = {Phytophthora cinnamomi and oak decline in southern Europe. Environmental constraints including climate change}, journal = {Ann. For. Sci.}, volume = {53}, year = {1996}, pages = {347-358}, doi = {10.1051/forest:19960217}, url = {http://dx.doi.org/10.1051/forest:19960217}, author = {C.M. Brasier} } @proceedings {brasier1999role, title = {The role of Phytophthora pathogens in forests and semi-natural communities in Europe and Africa}, year = {1999}, month = {2000}, pages = {6{\textendash}13}, publisher = {International Union of Forestry Research Organizations Working Party 7.02.09.}, address = {Forest Research Laboratory, Oregon State University, Corvallis, OR}, author = {C.M. Brasier}, editor = {Hansen, E.M. and Sutton, W.} } @conference {brasier2002pathogenicity, title = {Pathogenicity of Phytophthora ramorum isolates from North America and Europe to bark of European Fagaceae, American Quercus rubra and other forest trees}, booktitle = {Sudden oak death, a science symposium - the state of our knowledge, USDA Forest Service and University of California, Berkeley.}, year = {2002}, pages = {30{\textendash}31}, author = {C.M. Brasier and Rose, J. and Kirk, S.A. and Webber, JF} } @article {brasier2006recent, title = {Recent developments in Phytophthora diseases of trees and natural ecosystems in Europe}, journal = {Progress in Research on Phytophthora Diseases of Forest Trees. Proceedings, 3rd Int. IUFRO Working Party}, volume = {7}, number = {09}, year = {2006}, pages = {11{\textendash}17}, author = {C.M. Brasier and T. Jung} } @article {Brasier2005853, title = {Phytophthora kernoviae sp. nov., an invasive pathogen causing bleeding stem lesions on forest trees and foliar necrosis of ornamentals in the UK}, journal = {Mycological Research}, volume = {109}, number = {8}, year = {2005}, pages = {853 - 859}, abstract = {

A new Phytophthora pathogen of trees and shrubs, previously informally designated Phytophthora taxon C, is formally named here as P. kernoviae. P. kernoviae was discovered in late 2003 during surveys of woodlands in Cornwall, south-west England, for the presence of another invasive pathogen, P. ramorum. P. kernoviae is self-fertile (homothallic), having plerotic oogonia, often with distinctly tapered stalks and amphigynous antheridia. It produces papillate sporangia, sometimes markedly asymmetric with medium length pedicels. Its optimum temperature for growth is ca 18 ${\i}nfty$C and upper limit ca 26${\i}nfty$. Currently, P. kernoviae is especially noted for causing bleeding stem lesions on mature Fagus sylvatica and foliar and stem necrosis of Rhododendron ponticum. P. kernoviae is the latest of several invasive tree Phytophthoras recently identified in the UK. Its geographical origins and the possible plant health risk it poses are discussed.

}, issn = {0953-7562}, doi = {DOI: 10.1017/S0953756205003357}, url = {http://www.sciencedirect.com/science/article/B7XMR-4RS503Y-5/2/2264e8910ee36f4e72255d6160ebf9e4}, author = {Clive M. Brasier and Paul A. Beales and KIRK,Susan A. and Denman,Sandra and Joan Rose} } @article {brasier_phytophthora_2010, title = {Phytophthora lateralis discovered in an old growth Chamaecyparis forest in Taiwan.}, journal = {Plant pathology}, volume = {59}, number = {4}, year = {2010}, pages = {595{\textendash}603}, keywords = {phylogeny}, issn = {00320862}, doi = {http://dx.doi.org/10.1111/j.1365-3059.2010.02278.x}, author = {C.M. Brasier and A. Vannini and T.T. Chang and A.M. Vettraino} } @article {PPA:PPA1886, title = {The biosecurity threat to the UK and global environment from international trade in plants}, journal = {Plant Pathology}, volume = {57}, number = {5}, year = {2008}, pages = {792{\textendash}808}, publisher = {Blackwell Publishing Ltd}, abstract = {Native plant communities, woodlands and landscapes in the UK and across the world are suffering from pathogens introduced by human activities. Many of these pathogens arrive on or with living plants. The potential for damage in the future may be large, but current international regulations aimed at reducing the risks take insufficient account of scientific evidence and, in practice, are often highly inadequate. In this Letter I outline the problems and discuss some possible approaches to reducing the threats.}, keywords = {biosecurity, forests, invasive pathogens, natural ecosystems, PLANT diseases, plant health}, issn = {1365-3059}, doi = {10.1111/j.1365-3059.2008.01886.x}, url = {http://dx.doi.org/10.1111/j.1365-3059.2008.01886.x}, author = {C.M. Brasier} } @article {4630, title = {Phytophthora species recovered from the Connecticut River Valley in Massachusetts, USA}, journal = {Mycologia}, volume = {108}, year = {2016}, month = {Aug-01-2017}, pages = {6 - 19}, abstract = {

Little is currently known about the assemblage of Phytophthora species in northeastern North America, representing a gap in our understanding of species incidence. Therefore, Phytophthora species were surveyed at 20 sites in Massachusetts, with 16 occurring in the Connecticut River Valley. Many of the sampled waterways were adjacent to active agricultural lands, yet were buffered by mature floodplain forests composed of Acer, Platanus, Populus and Ulmus. Isolates were recovered with three types of baits (rhododendron leaves, pear, green pepper) in 2013 and water filtration in 2014. Overall, 457 isolates of Phytophthora were recovered and based on morphological characters and rDNA internal transcribed spacer (ITS), β-tubulin (β-tub) and cytochrome oxidase c subunit I (cox1) sequences, 18 taxa were identified, including three new species: P. taxon intercalaris, P. taxon caryae and P. taxon pocumtuck. In addition, 49 isolates representing five species of Phytopythium also were identified. Water filtration captured a greater number of taxa (18) compared to leaf and fruit baits (12). Of the three bait types rhododendron leaves yielded the greatest number of isolates and taxa, followed by pear and green pepper, respectively. Despite the proximity to agricultural lands, none of the Phytophthora species baited are considered serious pathogens of vegetable crops in the region. However, many of the recovered species are known woody plant pathogens, including four species in the P. citricola s.l. complex that were identified: P. plurivora, P. citricola III, P. pini and a putative novel species, referred to here as P. taxon caryae. An additional novel species, P. taxon pocumtuck, is a close relative of P. borealis based on cox1 sequences. The results illustrate a high level of Phytophthora species richness in the Connecticut River Valley and that major rivers can serve as a source of inoculum for pathogenic Phytophthora species in the northeast.

}, issn = {0027-5514}, doi = {10.3852/15-038}, url = {https://www.tandfonline.com/doi/full/10.3852/15-038}, author = {Brazee, Nicholas J. and Wick, Robert L. and Hulvey, Jonathan P.} } @article {4703, title = {Diversity and Pathogenicity of Phytophthora Species Associated with Declining Alder Trees in Italy and Description of Phytophthora alpina sp. nov}, journal = {Forests}, volume = {11}, year = {2020}, month = {Aug-05-2020}, pages = {848}, abstract = {

Extensive decline and mortality events of alder trees have recently been observed in several riparian ecosystems in Italy. Since there is little information about the aetiology of this disease and given the high ecological relevance of riparian ecosystems, an in-depth study was conducted in three sites spanning from the Mediterranean to Alpine regions. From spring 2019 to spring 2020, 261 samples of bleeding cankers, rhizosphere soil and leaves used as baits along waterways were collected and used for Phytophthora isolation. Based on morphology, colony appearance and DNA sequence data, 10 species belonging to 6 clades were identified. These included P. plurivora (84 isolates), P. pseudocryptogea (50), P. hydropathica (18), P. gonapodyides (14), P. bilorbang (13), P. pseudosyringae (12), P. lacustris (11), P. acerina (7), P. cactorum (1) and one isolate of the hybrid Phytophthora {\texttimes}serendipita. In addition, two new Phytophthora species, one of which is described here as Phytophthora alpina sp. nov., were isolated. The pathogenicity of P. alpina and other species obtained from samples collected in the green alder stand was assessed on 3-year-old seedlings. All species proved to be pathogenic on green alder causing symptoms congruent with field observations. Results obtained have allowed us to expand knowledge about alder decline aetiology. The diversity of pathogenicity of Phytophthora species associated with symptomatic alder trees suggested that no single agent is responsible for the disease, but that it is the result of multiple infections of different Phytophthora species, variable in assemblages among sites.

}, doi = {10.3390/f11080848}, url = {https://www.mdpi.com/1999-4907/11/8/848/htm}, author = {Bregant, Carlo and Sanna, Gian Paolo and Bottos, Adriano and Maddau, Lucia and Montecchio, Lucio and Linaldeddu, Benedetto T.} } @article {4258, title = {Phytophthora palmivora}, volume = {Number 12}, year = {2005}, pages = {2 pp}, publisher = {American Samoa Community College Community \& Natural Resources Cooperative Research \& Extension }, abstract = {

The organism that caused the 1845-46 Irish Potato Famine was named Phytophthora, the {\textquotedblleft}plant destroyer{\textquotedblright}. Though initially considered a fungus, or water mold, this organism is more like certain algae and has been moved from the kingdom Fungi to Chromista. There are about 80 species of Phytophthora, all damaging to plants. One of the most common tropical species is P. palmivora, with more than 150 plant hosts. Some of the most important hosts are black pepper (Piper nigrum), rubber (Hevea brasilensis), durian (Durio zibethinus), coconut (Co- cos nucifera), cocoa (Theobroma cacao), breadfruit (Artocarpus altilis), and papaya (Carica papaya). In American Samoa, the last three hosts are attacked by P. palmivora.

}, url = {http://www2.ctahr.hawaii.edu/adap/ASCC_LandGrant/Dr_Brooks/BrochureNo12.pdf}, author = {Brooks, F} } @article {PPA:PPA1511, title = {Colonization of tree xylem by Phytophthora ramorum, P. kernoviae and other Phytophthora species}, journal = {Plant Pathology}, volume = {56}, number = {2}, year = {2007}, pages = {227{\textendash}241}, publisher = {Blackwell Publishing Ltd}, abstract = {

The aetiology and frequency of Phytophthora spp. in discoloured xylem tissue beneath phloem lesions was investigated in a range of broadleaved trees infected with P. ramorum, P. kernoviae, P. cambivora, P. citricola and other species. Isolation was attempted from the inner surface of 81 sterilized discoloured wood panels (6 {\texttimes} 4 cm) from 53 trees. Discolouration mostly extended 1{\textendash}5 mm into the xylem (75\%), but incursions of 6{\textendash}10 mm (10\%) and 10{\textendash}25 mm (15\%) were frequent. Of the wood panels, 81\% yielded Phytophthora spp. In 66 cases, both a wood panel and an overlying phloem panel were sampled. In 56\% of these, a Phytophthora, sp. was isolated from both the wood and the phloem panel. In 23\% the Phytophthora sp. was isolated from the wood panel only and in 8\% from the phloem panel only. Small {\textquoteleft}island{\textquoteright} phloem lesions, often in linear arrays adjacent to main lesions, were a common feature of Fagus sylvatica and Quercus spp. trees infected with P. ramorum or P. kernoviae. Island lesions were often connected by underlying strips or intermittent pits of discoloured xylem in line with the wood grain. Phytophthora ramorum, P. kernoviae and other Phytophthora spp. were successfully isolated from these connecting xylem features with P. ramorum and P. kernoviae also recovered from discoloured tissue 5{\textendash}25 mm below exposed xylem surfaces 24{\textendash}27 months after the overlying phloem was removed. These results show that these pathogens commonly occupy xylem beneath phloem lesions; that they can perennate in xylem tissue; that they can spread in xylem tissue ahead of phloem lesions; and indicate that they may initiate new phloem lesions in this way. Such colonization must lead to at least local xylem dysfunction. It is recommended that, if xylem discoloration is present, isolation of the Phytophthora sp. should be attempted from the xylem as well as the bark; also, that removal of infected outer sapwood should be undertaken during excision of bleeding lesions for disease control and in protocols aimed at preventing national or international spread of these tree stem pathogens.

}, keywords = {bark lesions, bleeding cankers, phloem, Phytophthora, tree stem diseases, wood}, issn = {1365-3059}, doi = {10.1111/j.1365-3059.2006.01511.x}, url = {http://dx.doi.org/10.1111/j.1365-3059.2006.01511.x}, author = {Brown, A. V. and C.M. Brasier} } @article {1306, title = {A leaf and twig disease of English holly caused by Phytophthora ilicis N. sp.}, journal = {Phytopathology}, volume = {47}, year = {1957}, pages = {95-101}, abstract = {

This is an expanded account from Oregon State College, Corvallis, of a disease of holly caused by Phytophthora sp. [34, p. 328], for which the name P. ilicis n.sp. is proposed. It was shown that the defoliation which accompanies the disease is due to the production of ethylene by infected leaf tissue. The disease develops from October to May, and is inactive in the summer. The pathogen is distinguishable from P. porri by its smaller oogonia, and from P. hibernalis and P. syringae by the consistent presence of amphigynous antheridia. On diseased holly tissues the sporangia have a shallow apical thickening and no papilla, and measure 18 to 30 by 30 to 50 (average 24 by 39) {\textmu}, with persistent pedicels, 5 to 15 {\textmu} long. Oogonia average 21 {\textmu} and oospores 18 {\textmu}, with a slightly yellow wall; antheridia average 13 by 1{\textmu}.

}, author = {Buddenhagen, I. W. and Young, R. A.} } @mastersthesis {1305, title = {A Phytophthora-induced disease of English holly, Ilex aquifolium L.}, volume = {MS}, year = {1954}, school = {Oregon State University}, type = {masters}, address = {Corvallis}, author = {Buddenhagen, I. W.} } @mastersthesis {1197, title = {Root rots caused by Phycomycetes}, year = {1927}, pages = {51 pp.}, school = {University of Utrecht, Meded. Phytopath. Lab. Willie Commelin Scholten Baarn 11: 4,7.}, type = {masters}, author = {Buisman, C.J.} } @article {4078, title = {Re-evaluation of Phytophthora species isolated during 30 years of vegetation health surveys in western Australia using molecular techniques}, journal = {Plant Disease}, volume = {93}, year = {2009}, month = {03/2009}, pages = {215 - 223}, abstract = {

For 30 years, large-scale aerial photography has been used to map the extent of Phytophthora dieback disease in native forests in the southwest of Western Australia, with validation of the observations involving routine testing of soil and root samples for the presence of Phytophthora cinnamomi. In addition to P. cinnamomi, six morpho-species have been identified using this technique: P. citricola, P. megasperma, P. cryptogea, P. drechsleri, P. nicotianae, and P. boehmeriae. In recent years, many new Phytophthora species have been described worldwide, often with similar morphology to existing species; thus, as many of the isolates collected in Western Australia have been difficult to identify based on morphology, molecular identification of the morpho-species is required. Based on amplification of the internal transcribed spacer (ITS) region of the rDNA gene, sequence data of more than 230 isolates were compared with those of existing species and undescribed taxa. P. inundata, P. asparagi, P. taxon PgChlamydo, P. taxon personii, and P. taxon niederhauserii were identified based on sequence data. Phylogenetic analysis revealed that nine potentially new and undescribed taxa can be distinguished. Several of the new taxa are morphologically indistinguishable from species such as P. citricola, P. drechsleri, and P. megasperma. In some cases, the new taxa are closely related to species with similar morphology (e.g., P.sp.4 and P. citricola). However, the DNA sequences of other new taxa such as P.sp.3 and P.sp.9 show that they are not closely related to morphologically similar species P. drechsleri and P. megasperma, respectively. Most of the new taxa have been associated with dying Banksia spp., while P.sp.2 and P.sp.4 have also been isolated from dying Eucalyptus marginata (jarrah). Some taxa (P.sp.3, 6, and 7) appear to have limited distribution, while others like P.sp.4 are widespread.

}, issn = {0191-2917}, doi = {10.1094/PDIS-93-3-0215}, author = {Burgess, Treena I. and Webster, Janet L. and Ciampini, Juanita A. and White, Diane and Hardy, Giles E. StJ. and Stukely, Michael J. C.} } @article {4706, title = {Towards a best practice methodology for the detection of Phytophthora species in soils}, journal = {Plant Pathology}, volume = {Early view}, year = {2020}, month = {Nov-07-2020}, abstract = {

The genus Phytophthora contains species that are major pathogens worldwide, affecting a multitude of plant species across agriculture, horticulture, forestry, and natural ecosystems. Here, we concentrate on those species that are dispersed through soil and water, attacking the roots of the plants, causing them to rot and die. The intention of this study was to compare the soil baiting protocol developed by the Centre for Phytophthora Science and Management (CPSM) with two other baiting methods used in Australia. The aim was to demonstrate the effectiveness of each protocol for soil baiting Phytophthora species in different substrates. Three experiments were conducted: the first to test the sensitivity of each method to detect Phytophthora cinnamomi, the second to test the effect of substrate type (sand or loam), and the third to test the detection of species (P. cinnamomi, P. multivora, or P. pseudocryptogea). The specificity of different plant species baits was compared within and between the methods. Substrate type influenced isolation in all methods; however, the CPSM method was superior regardless of substrate, albeit slower than one of the other methods for one substrate. Comparing bait species between the three methods, Quercus ilex was the most attractive bait for P. cinnamomi, particularly in the CPSM method. The choice of protocol affected the isolation associated with each bait type. Overall, the multiple bait system used by CPSM was shown to provide the most sensitive and reliable detection of Phytophthora species from soil samples.

}, issn = {0032-0862}, doi = {10.1111/ppa.13312}, url = {https://bsppjournals.onlinelibrary.wiley.com/doi/abs/10.1111/ppa.13312?af=R}, author = {Burgess, Treena I. and L{\'o}pez-Villamor, {\'a}n and Paap, Trudy and Williams, Briony and Belhaj, Rajah and Crone, Michael and Dunstan, William and Howard, Kay and Hardy, Giles E. St. J.} } @article {4487, title = {Current and projected global distribution of Phytophthora cinnamomi, one of the world{\textquoteright}s worst plant pathogens}, journal = {Global Change Biology}, year = {2016}, month = {Jan-09-2016}, abstract = {

Globally, Phytophthora cinnamomi is listed as one of the 100 worst invasive alien species and active management is required to reduce impact and prevent spread in both horticulture and natural ecosystems. Conversely, there are regions thought to be suitable for the pathogen where no disease is observed. We developed a CLIMEX model for the global distribution of P. cinnamomi based on the pathogen{\textquoteright}s response to temperature and moisture and by incorporating extensive empirical evidence on the presence and absence of the pathogen. The CLIMEX model captured areas of climatic suitability where P. cinnamomi occurs that is congruent with all available records. The model was validated by the collection of soil samples from asymptomatic vegetation in areas projected to be suitable by the model for which there were few records. DNA was extracted and the presence or absence of P. cinnamomi determined by high throughput sequencing (HTS). While not detected using traditional isolation methods, HTS detected P. cinnamomi at higher elevations in eastern Australia and central Tasmania as projected by the CLIMEX model. Further support for the CLIMEX model was obtained by using the large dataset from southwest Australia where the proportion of positive records in an area is related to the Ecoclimatic Index value for the same area. We provide for the first time a comprehensive global map of the current P. cinnamomi distribution, an improved CLIMEX model of the distribution, and a projection to 2080 of the distribution with predicted climate change. This information provides the basis for more detailed regional scale modelling and supports risk assessment for governments to plan management of this important soil-borne plant pathogen.

}, doi = {http://dx.doi.org/10.1111/gcb.13492 }, url = { http://dx.doi.org/10.1111/gcb.13492 }, author = {Burgess, Treena I. and Scott, John K. and McDougall, Keith L. and Stukely, Michael J. C. and Crane, Colin and Dunstan, William A. and Brigg, Frances and Andjic, Vera and White, Diane and Rudman, Tim and Arentz, Frans and Ota, Noboru and Hardy, Giles E. St.J.} } @article {4257, title = {Report of the imperial mycologist, 1918{\textendash}1919}, journal = {Science Report Institute Pusa}, pages = {82 pp}, author = {Butler, EJ} } @proceedings {4218, title = {Bud rot of coconut and other palms}, year = {1924}, pages = {145-147}, author = {Butler, EJ} }