02304nas a2200169 4500008004100000245012700041210006900168260001600237300001100253490000700264520172100271100001701992700001802009700002202027700002302049856006202072 2020 eng d00aMigratory passerine birds in Britain carry Phytophthora ramorum inoculum on their feathers and “feet” at low frequency0 aMigratory passerine birds in Britain carry Phytophthora ramorum  cDec-09-2019 ae125690 v503 a

In this study, we investigated whether birds could be vectors facilitating long‐distance spread of Phytophthora ramorum in Britain. Migratory bird species associated with the main sporangium‐producing host plants and most likely to pick up P. ramorum spores were considered. Swabs were taken from the flank and “feet” of 1,014 birds over a 12‐month period (April 2011–March 2012) in the west of Britain and subsequently analyzed for the presence of P. ramorum using nested PCR. Ten positive samples from 10 birds were identified: three in Cornwall, one in Devon, three in Gloucestershire, two in north Wales and one in Merseyside. Phytophthora ramorum was detected on samples from four species of thrushes (Redwing Turdus iliacus, Fieldfare T. pilaris, Blackbird T. merula and Song Thrush T. philomelos) and one species of warbler (Chiffchaff Phylloscopus collybita). All birds that tested positive were sampled in late autumn and winter (October–February), when long‐distance movements (over 100 km) would have stopped. The low incidence of P. ramorum found using PCR suggests that the incidence of inoculum, whether viable or not, on birds was low. The apparently low incidence of inoculum on birds suggests migratory passerine birds can carry P. ramorum inoculum on their feathers and “feet,” albeit at low frequency. The dates of positive samples indicate that birds would not have been moving long distances at the time but further work is needed to estimate the extent of their contribution to the spread of P. ramorum in Britain.

1 aDadam, Daria1 aSiasou, Eleni1 aWoodward, Stephen1 aClark, Jacquie, A. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/efp.1256901110nas a2200121 4500008004100000245007600041210006800117300001000185490000600195520071900201100001400920856005400934 1974 eng d00aThe occurrence of Phytophthora palmivora (Butl.) Butl. in soil in Ghana0 aoccurrence of Phytophthora palmivora Butl Butl in soil in Ghana a37-410 v73 a

The occurrence of Phytophthora palmivora (But!.) But!. in soil was studied over 2 consecutive years by baiting the fungus with healthy cocoa pods. The fungus was frequently found in soils of a forest reserve, an abandoned cocoa farm and in farms still under cocoa cultivation; its activity, however, differed under the three soil conditions. Fluctuations in the occurrence of P. palmivora in soil did not depend on atmospheric temperature. At Obomeng, the fungus was isolated more frequently from a cocoa farm than from either an abandoned cocoa farm or a forest area. The isolation of P. palmivora from the uncultivated forest soil indicates that the fungus is indigenous to forest soils.

1 aDakwa, JT uhttp://gains.org.gh/articles/gjas_v7_1_p37_41.pdf03758nas a2200289 4500008004100000245010600041210006900147260001600216490000700232520286200239100002103101700001803122700002503140700002003165700001803185700002003203700002703223700001703250700002303267700001603290700002303306700002003329700002603349700002403375700002103399856004803420 2019 eng d00aMitotic Recombination and Rapid Genome Evolution in the Invasive Forest Pathogen Phytophthora ramorum0 aMitotic Recombination and Rapid Genome Evolution in the Invasive cMar-12-20190 v103 a

Invasive alien species often have reduced genetic diversity and must adapt to new environments. Given the success of many invasions, this is sometimes called the genetic paradox of invasion. Phytophthora ramorum is invasive, limited to asexual reproduction within four lineages, and presumed clonal. It is responsible for sudden oak death in the United States, sudden larch death in Europe, and ramorum blight in North America and Europe. We sequenced the genomes of 107 isolates to determine how this pathogen can overcome the invasion paradox. Mitotic recombination (MR) associated with transposons and low gene density has generated runs of homozygosity (ROH) affecting 2,698 genes, resulting in novel genotypic diversity within the lineages. One ROH enriched in effectors was fixed in the NA1 lineage. An independent ROH affected the same scaffold in the EU1 lineage, suggesting an MR hot spot and a selection target. Differences in host infection between EU1 isolates with and without the ROH suggest that they may differ in aggressiveness. Non-core regions (not shared by all lineages) had signatures of accelerated evolution and were enriched in putative pathogenicity genes and transposons. There was a striking pattern of gene loss, including all effectors, in the non-core EU2 genome. Positive selection was observed in 8.0% of RxLR and 18.8% of Crinkler effector genes compared with 0.9% of the core eukaryotic gene set. We conclude that the P. ramorum lineages are diverging via a rapidly evolving non-core genome and that the invasive asexual lineages are not clonal, but display genotypic diversity caused by MR.

IMPORTANCE Alien species are often successful invaders in new environments, despite the introduction of a few isolates with a reduced genetic pool. This is called the genetic paradox of invasion. We found two mechanisms by which the invasive forest pathogen causing sudden oak and sudden larch death can evolve. Extensive mitotic recombination producing runs of homozygosity generates genotypic diversity even in the absence of sexual reproduction, and rapid turnover of genes in the non-core, or nonessential portion of genome not shared by all isolates, allows pathogenicity genes to evolve rapidly or be eliminated while retaining essential genes. Mitotic recombination events occur in genomic hot spots, resulting in similar ROH patterns in different isolates or groups; one ROH, independently generated in two different groups, was enriched in pathogenicity genes and may be a target for selection. This provides important insights into the evolution of invasive alien pathogens and their potential for adaptation and future persistence.

1 aDale, Angela, L.1 aFeau, Nicolas1 aEverhart, Sydney, E.1 aDhillon, Braham1 aWong, Barbara1 aSheppard, Julie1 aBilodeau, Guillaume, J1 aBrar, Avneet1 aTabima, Javier, F.1 aShen, Danyu1 aBrasier, Clive, M.1 aTyler, Brett, M1 aGrünwald, Niklaus, J1 aHamelin, Richard, C1 aTaylor, John, W. uhttps://mbio.asm.org/content/10/2/e02452-1800497nas a2200109 4500008004100000245008800041210006900129260003900198100001800237700001600255856011600271 2003 eng d00aPathways of movement for Phytophthora ramorum, the causal agent of Sudden Oak Death0 aPathways of movement for Phytophthora ramorum the causal agent o bAmerican Phytopathological Society1 aDavidson, J M1 aShaw, C G T uhttps://forestphytophthoras.org/references/pathways-movement-phytophthora-ramorum-causal-agent-sudden-oak-death00450nas a2200133 4500008004100000245006900041210006900110300001200179490000700191100001800198700001900216700001500235856006600250 2008 eng d00aSources of inoculum for Phytophthora ramorum in a redwood forest0 aSources of inoculum for Phytophthora ramorum in a redwood forest a860-8660 v981 aDavidson, J M1 aPatterson, H A1 aRizzo, D M uhttp://apsjournals.apsnet.org/doi/abs/10.1094/PHYTO-98-8-086002274nas a2200169 4500008004100000245009200041210006900133300001200202490000800214520169100222100002601913700002601939700002501965700002701990700002002017856006702037 2011 eng d00aForest type influences transmission of Phytophthora ramorum in California oak woodlands0 aForest type influences transmission of Phytophthora ramorum in C a492-5010 v1013 a

The transmission ecology of Phytophthora ramorum from bay laurel (Umbellularia californica) leaves was compared between mixed-evergreen and redwood forest types throughout winter and summer disease cycles in central, coastal California. In a preliminary multisite study, we found that abscission rates of infected leaves were higher at mixed-evergreen sites. In addition, final infection counts were slightly higher at mixed-evergreen sites or not significantly different than at redwood sites, in part due to competition from other foliar pathogens at redwood sites. In a subsequent, detailed study of paired sites where P. ramorum was the main foliar pathogen, summer survival of P. ramorum in bay laurel leaves was lower in mixed-evergreen forest due to lower recovery from infected attached leaves and higher abscission rates of infected leaves. Onset of inoculum production and new infections of bay laurel leaves occurred later in mixed-evergreen forest. Mean inoculum levels in rainwater and final infection counts on leaves were higher in redwood forest. Based on these two studies, lower summer survival of reservoir inoculum in bay laurel leaves in mixed-evergreen forest may result in delayed onset of both inoculum production and new infections, leading to slower disease progress in the early rainy season compared with redwood forest. Although final infection counts also will depend on other foliar pathogens and disease history, in sites where P. ramorum is the main foliar pathogen, these transmission patterns suggest higher rates of disease spread in redwood forests during rainy seasons of short or average length.

1 aDavidson, Jennifer, M1 aPatterson, Heather, A1 aWickland, Allison, C1 aFichtner, Elizabeth, J1 aRizzo, David, M uhttp://apsjournals.apsnet.org/doi/abs/10.1094/PHYTO-03-10-006400486nas a2200145 4500008004100000245007700041210006900118260001400187100001800201700001400219700001800233700001600251700001500267856005800282 2003 eng d00aSudden oak death and associated diseases caused by Phytophthora ramorum.0 aSudden oak death and associated diseases caused by Phytophthora  cJuly 20031 aDavidson, J M1 aWerres, S1 aGarbelotto, M1 aHansen, E M1 aRizzo, D M uhttp://www.plantmanagementnetwork.org/php/shared/sod/00550nas a2200157 4500008004100000245008100041210006900122300001200191490000700203100002600210700002500236700002600261700002100287700002000308856006400328 2005 eng d00aTransmission of Phytophthora ramorum in mixed-evergreen forest in California0 aTransmission of Phytophthora ramorum in mixedevergreen forest in a587-5960 v951 aDavidson, Jennifer, M1 aWickland, Allison, C1 aPatterson, Heather, A1 aFalk, Kristen, R1 aRizzo, David, M uhttp://apsjournals.apsnet.org/doi/abs/10.1094/PHYTO-95-058700439nas a2200109 4500008004100000245007600041210006900117300001400186490000700200100001300207856010900220 1938 eng d00aRoot-rot of sweet chestnut and beech caused by species of Phytophthora.0 aRootrot of sweet chestnut and beech caused by species of Phytoph a101–1160 v121 aDay, W R uhttps://forestphytophthoras.org/references/root-rot-sweet-chestnut-and-beech-caused-species-phytophthora02656nas a2200289 4500008004100000022001400041245008900055210006900144260002900213300001400242490000700256520181900263653002002082653001302102653001502115653002702130653001402157653001602171100002102187700001902208700001802227700001602245700002202261700001202283700001602295856005502311 2010 eng d a1365-305900aEffect of host factors on the susceptibility of Rhododendron to Phytophthora ramorum0 aEffect of host factors on the susceptibility of Rhododendron to  bBlackwell Publishing Ltd a301–3120 v593 a

Phytophthora ramorum causes sudden oak death (SOD) in western coastal forests of the USA. In Europe, the pathogen is mainly present in the nursery industry, particularly on Rhododendron. Because of the primary role of Rhododendron as a host and potentially as a vector, the effect of Rhododendron host factors on P. ramorum susceptibility and sporulation was investigated. Inoculation methods using either wounded or non-wounded detached leaves were applied to 59 Rhododendron cultivars and 22 botanical species, replicated in three separate years. All Rhododendron species and cultivars were susceptible when using wounded leaves, but not when using non-wounded leaves, suggesting a resistance mechanism operating at the level of leaf penetration. Using a regression tree analysis, the cultivars and species were split into four susceptibility classes. Young leaves were more susceptible than mature leaves when wounded, but less susceptible when non-wounded. This effect was not correlated with leaf hydrophobicity or the number of leaf hairs. The presence or the type of rootstock did not affect the cultivar susceptibility level. Sporangia and chlamydospore production in the leaf lesions varied widely among Rhododendron cultivars and was not correlated with the susceptibility level. The susceptibility to P. ramorum correlated well with the susceptibility to P. citricola and P. hedraiandra × cactorum, suggesting that the resistance mechanisms against these species are non-specific. Susceptibility to P. kernoviae was low for most cultivars. These findings have implications for detection, spread and disease control, and are therefore important in pest risk assessment.

10ahost resistance10aleaf age10aleaf hairs10aPhytophthora kernoviae10arootstock10asporulation1 aDe Dobbelaere, I1 aVercauteren, A1 aSpeybroeck, N1 aBerkvens, D1 aVan Bockstaele, E1 aMaes, M1 aHeungens, K uhttp://dx.doi.org/10.1111/j.1365-3059.2009.02212.x00431nas a2200121 4500008004100000245005800041210005800099300000800157490000700165100001600172700001900188856010200207 1991 eng d00aFirst report of Phytophthora lateralis on Pacific yew0 aFirst report of Phytophthora lateralis on Pacific yew a9680 v751 aDeNitto, GA1 aKliejunas, J T uhttp://www.apsnet.org/publications/PlantDisease/BackIssues/Documents/1991Abstracts/PD_75_968C.htm02485nas a2200253 4500008004100000022001400041245012000055210006900175260002600244300001400270490000700284520170700291653002501998653001302023653002802036653001202064653001902076653002102095100001402116700001402130700001702144700001502161856005502176 2005 eng d a1365-305900aIn vitro leaf inoculation studies as an indication of tree foliage susceptibility to Phytophthora ramorum in the UK0 aIn vitro leaf inoculation studies as an indication of tree folia bBlackwell Science Ltd a512–5210 v543 a

Leaves of 11 coniferous and 23 broad-leaved tree species important to UK forestry were tested for their susceptibility to the quarantine pathogen Phytophthora ramorum using a detached leaf assay. Two European and two USA isolates were used. Wounded and unwounded leaves were dipped in zoospore suspensions during summer; conifers were also tested in winter. Successful infection of tissue and amount of necrosis were assessed. Highly susceptible broad-leaved hosts included Aesculus hippocastanum, Fraxinus excelsior, Quercus ilex, Ulmus procera and, to a lesser extent, Castanea sativa, Q. cerris and Q. petraea, together with Umbellularia californica and rhododendrons. Acer pseudoplatanus, Alnus glutinosa, Carpinus betulus, Corylus avellana, Fagus sylvatica, Prunus avium, Q. robur, Q. rubra and Q. suber showed consistently low susceptibility. Conifer species including Abies procera, Picea abies, P. sitchensis, Pseudotsuga menziesii, Sequoia sempervirens and Tsuga heterophylla were also susceptible. Pseudotsuga menziesii and A. procera were severely affected. Pinus contorta, P. nigra var. maritima and P. sylvestris were virtually resistant, while Taxus baccata was only slightly affected. Increased necrosis was apparent on leaves that were wounded prior to inoculation. These results extend the known range of trees that P. ramorum is able to attack and confirm its relative host-nonspecificity.

10abroad-leaved species10aconifers10adetached leaf dip assay10afoliage10aforest species10aSudden oak death1 aDenman, S1 aKirk, S A1 aBrasier, C M1 aWebber, JF uhttp://dx.doi.org/10.1111/j.1365-3059.2005.01243.x01895nas a2200181 4500008004100000022001400041245009500055210006900150260002900219300001400248490000700262520133000269100001401599700001401613700001601627700001501643856005501658 2009 eng d a1365-233800aPhytophthora ramorum and Phytophthora kernoviae on naturally infected asymptomatic foliage0 aPhytophthora ramorum and Phytophthora kernoviae on naturally inf bBlackwell Publishing Ltd a105–1110 v393 a

Phytophthora ramorum and Phytophthora kernoviae are recently discovered invasive Phytophthoras causing leaf necrosis and shoot tip dieback mostly on ornamental and forest understorey species, but also cause bleeding cankers on stems of a wide range of tree species. Sporulation occurs only on infected shoots or fruits and foliage so foliar hosts are central to the disease epidemiology. In field trials to assess infection in trap plants exposed to natural inoculum of P. ramorum and P. kernoviae on rhododendron in south west England, it was discovered that leaves of the trap plants (Rhododendron ‘Cunninghams White’) and holm oak (Quercus ilex) were asymptomatically infected and supported sporulation of both pathogens. More than half the rhododendron trap plants exposed to inoculum of P. kernoviae became infected compared with approximately a third of those exposed to P. ramorum in a natural situation. Approximately one third of the infections were detected from asymptomatic foliage for both pathogens. The significance of these findings for plant health regulation based on visual inspection as a measure to prevent introduction and dissemination of both these pathogens is explored and research gaps identified.

1 aDenman, S1 aKirk, S A1 aMoralejo, E1 aWebber, JF uhttp://dx.doi.org/10.1111/j.1365-2338.2009.02243.x00572nas a2200121 4500008004100000020002200041245007200063210006900135260009800204300001000302100004900312856008900361 2008 eng d a978-1-74152-795-700aVictoria’s Public Land Phytophthora cinnamomi Management Strategy0 aVictoria s Public Land Phytophthora cinnamomi Management Strateg bDepartment of Sustainability and Environment, PO Box 500, East Melbourne, Victoria, Australia a37 pp1 aDepartment of Sustainability and Environment uhttp://lakeshub.com/wp-content/uploads/2013/04/Phytophthora_cinnamomi_Strategy-1.pdf04536nas a2200181 4500008004100000022001400041245010700055210006900162260001600231300000900247490000800256520395000264100001604214700002104230700001704251700002004268856006604288 2016 eng d a0191-291700aFirst Report of Phytophthora chlamydospora Causing Root Rot on Walnut (Juglans regia ) Trees in Turkey0 aFirst Report of Phytophthora chlamydospora Causing Root Rot on W cJan-11-2016 a23360 v1003 a

Common or English (Persian) walnut (Juglans regia L.) is an important nut crop in Turkey, which is the fourth largest producer of walnut in the world. In August 2015, we observed sudden wilt and subsequent death associated with root rot. Approximately 15% of 2,000 5- to 7-year-old J. regia cv. Chandler trees grafted on wild walnut (J. regia) in waterlogged areas of a commercial walnut orchard in Bingöl province of eastern Turkey were affected. Most fine roots were completely rotted and the inner bark of infected lateral and taproots showed a reddish brown discoloration. Tissue samples taken from the margins of root lesions of 10 symptomatic trees were placed on grated carrot corn meal agar (GCCMA) (Türkölmez et al. 2015) amended with 5 mg of pimaricin, 250 mg of ampicillin, 10 mg of rifampicin, 100 mg of pentachloronitrobenzene, and 50 mg of hymexazol per liter (P5ARPH). Plates were incubated for 5 days at 28°C in the dark. A Phytophthora species was consistently isolated from the tissues. On GCCMA, colonies had a distinct petaloid growth pattern and produced abundant spherical, thin-walled, intercalary and terminal chlamydospores (30 to 46 μm diameter) and hyphal chains of globose to subglobose swellings. After incubation of mycelial disks in nonsterile soil extracts at 25°C, all isolates produced hyaline, nonpapillate, noncaducous sporangia of ovoid to obpyriform shape, with internal proliferation, measuring 34.5 to 56.5 μm in length, 27.0 to 39.5 μm wide, with a length/breadth ratio of 1.4 to 1.7, formed on unbranched or sympodial sporangiophores. Growth rate on carrot agar (CA) at 25°C was 3.3 to 3.5 mm d−1; the optimum and maximum temperatures for mycelium growth on CA were 29 and 37°C, respectively. All these characteristics were similar to those described for Phytophthora chlamydospora Brasier and Hansen (Hansen et al. 2015), previously known as P. taxon Pgchlamydo. Genomic DNA was extracted from three representative isolates. The internal transcribed spacer (ITS) region of rDNA and cox2 gene regions were amplified using the ITS6/ITS4 and FMPhy10b/FMPhy8b primer pairs, respectively, and sequenced (GenBank accession nos. KU725882, KU725883, KU707216, KX446861, KX446862). BLAST searches of ITS region showed 100% identity to many P. chlamydospora isolates, including the ex-type culture P236 (AF541900) (Brasier et al. 2003), deposited in GenBank and of cox2 gene regions of two isolates had 100% identity with PD_01777_cox2 and PD_00174_cox2 accessions deposited at Phytophthora-ID databases, which confirmed the morphological identification. Pathogenicity of P. chlamydospora was evaluated using the soil infestation method on 10 1-year-old potted J. regia cv. Chandler seedlings by growing P. chlamydospora on sterilized millet seeds for 4 weeks at 29°C and adding infested millet seeds to potting soil at a rate of 3% (w/v). In 10 noninoculated control plants, sterilized millet seeds were added to the potting soil. Both inoculated and control plants were flooded for 24 h at 2 week intervals. All inoculated plants showed severe wilting within a month and necrosis on lateral and taproots and rot on fineroots after 2 months of incubation in a greenhouse where air temperatures ranged from 24 to 30°C, while control plants remained asymptomatic. Koch’s postulates were satisfied after reisolating P. chlamydospora, which was identified morphologically, from symptomatic roots of inoculated plants. P. chlamydospora has been previously recovered from several ornamental and woody species (Blomquist et al. 2012; Brasier et al. 2003; Ginetti et al. 2014), and to our knowledge, this is the first report of P. chlamydospora infection of walnut, which represents a new host for this pathogen.

1 aDerviş, S.1 aTürkölmez, Ş.1 aÇiftçi, O.1 aSerçe, Ç., U. uhttp://apsjournals.apsnet.org/doi/10.1094/PDIS-03-16-0306-PDN00448nas a2200133 4500008004100000245004500041210004500086260003100131300001200162100002100174700001300195700002100208856008500229 2004 eng d00aPhytophthora diseases of Theobroma cacao0 aPhytophthora diseases of Theobroma cacao aMontpellier, FrancebCIRAD a15–441 aDespreaux, Denis1 aCilas, C1 aDespreaux, Denis uhttps://forestphytophthoras.org/references/phytophthora-diseases-theobroma-cacao02739nas a2200193 4500008004100000022001400041245012200055210006900177260001600246300000600262490000700268520212300275100001902398700001902417700001802436700001802454700002002472856005302492 2014 eng d a1179-539500aPathogenicity of Phytophthora pluvialis to Pinus radiata and its relation with red needle cast disease in New Zealand0 aPathogenicity of Phytophthora pluvialis to Pinus radiata and its cJan-01-2014 a60 v443 a

Background

Red needle cast, a new foliage disease of Pinus radiata in New Zealand is described. The disease has been variable in incidence and severity both regionally and in different years. The early symptoms of discrete olive coloured lesions, often with a narrow dark resinous mark or band, were first recognised in winter of 2008 in plantation forests on the eastern coast of the North Island. These lesions develop further to result in rapid needle senescence and premature defoliation. The disease has been termed red needle cast in New Zealand as affected trees have a reddish appearance prior to the casting of the needles. The subsequent four years of monitoring have confirmed that, depending on location, symptoms are first observed in late autumn through late winter. Newly developing spring and summer foliage is seldom affected. Isolation from needles using a Phytophthora-selective medium frequently yielded an unknown species of Phytophthora which was subsequently found to be identical to Phytophthora pluvialis, a species described from Oregon, USA in 2013 where it is not associated with disease. Infection appears to be limited to the needles with no recoveries of Phytophthora pluvialis having been made from the roots, stems or branches. Occasionally a second species of Phytophthora, P. kernoviae, was also recovered from needles with the same symptoms.

Methods

Needle symptoms were described in the field from 2008-2012 with isolation onto Phytophthora selective media. Koch’s postulates was completed on potted plants and detached needles.

Results

Symptoms were reproduced on both detached needles and potted plants of Pinus radiata when inoculated with zoospore suspensions of Phytophthora pluvialis.

Conclusions

This paper presents evidence that Phytophthora pluvialis is the primary cause of red needle cast in New Zealand.

1 aDick, Margaret1 aWilliams, Nari1 aBader, Martin1 aGardner, Judy1 aBulman, Lindsay uhttp://www.nzjforestryscience.com/content/44/1/602365nas a2200289 4500008004100000022001400041245014300055210006900198260002900267300001400296490000800310520143500318653002001753653001601773653002501789653002201814653001501836653002501851653001801876100002101894700002101915700001801936700002101954700002201975700002301997856005502020 2008 eng d a1469-813700aEvidence for the role of synchronicity between host phenology and pathogen activity in the distribution of sudden oak death canker disease0 aEvidence for the role of synchronicity between host phenology an bBlackwell Publishing Ltd a505–5140 v1793 a

Variations in synchronicity between colonization rate by the pathogen and host phenology may account for unexplained spatial distribution of canker disease. The hypothesis that synchronous pathogenicity and host development are necessary for incidence of sudden oak death disease was tested by correlating seasonal variations in host cambial phenology and response to inoculation with Phytophthora ramorum.

10aexotic pathogen10ainoculation10aPhytophthora ramorum10aQuercus agrifolia10aresistance10aspatial distribution10asynchronicity1 aDodd, Richard, S1 aHüberli, Daniel1 aMayer, Wasima1 aHarnik, Tamar, Y1 aAfzal-Rafii, Zara1 aGarbelotto, Matteo uhttp://dx.doi.org/10.1111/j.1469-8137.2008.02450.x00426nas a2200109 4500008004100000245007000041210006600111300001200177490000700189100001700196856010300213 1931 eng d00aA crown rot of hollyhock caused by Phytophthora megasperma n. sp.0 acrown rot of hollyhock caused by Phytophthora megasperma n sp a513-5260 v211 aDrechsler, C uhttps://forestphytophthoras.org/references/crown-rot-hollyhock-caused-phytophthora-megasperma-n-sp01603nas a2200169 4500008004100000022001400041245011400055210006900169300000700238490000700245520105300252100001801305700001901323700001701342700002001359856005401379 2014 eng d a1179-539500aFirst evidence of genetic-based tolerance to red needle cast caused by Phytophthora pluvialis in radiata pine0 aFirst evidence of geneticbased tolerance to red needle cast caus a310 v443 a

BACKGROUND:Red needle cast (RNC) is a new needle disease of Pinus radiata D. Don (radiata pine) in New Zealand that is causing significant, but as-yet un-quantified, loss of growth and productivity. This foliar disease has recently been attributed to the infection of the needles by Phytophthora pluvialis Reeser, Sutton & E Hansen. Genetic improvement is seen as a possible solution to mitigate the effects of this needle disease on forest productivity.FINDINGS:To quantify the ability of genetics to provide a solution, RNC was assessed on a single clones-within-families genetics trial using two methods: the percentage needle cast that was attributable to red needle cast symptoms; and the percentage needle cast where the causal agent was not clearly identifiable. Both needle cast assessment methods were found to be heritable (h2 0.21-0.31).CONCLUSIONS:Selecting for tolerance to RNC is likely to deliver healthier trees. More assessments across a number of sites and seasons are required to confirm this result.

1 aDungey, Heidi1 aWilliams, Nari1 aLow, Charlie1 aStovold, Graham uhttp://www.nzjforestryscience.com/content/44/1/3101103nas a2200145 4500008004100000245010200041210006900143260005100212300001200263490000700275520058600282100001700868700002100885856005100906 2005 eng d00aControl of Phytophthora cinnamomi with phosphite: some recent developments in application methods0 aControl of Phytophthora cinnamomi with phosphite some recent dev bAustralian Network for Plant Conservation Inc. a10–110 v343 a

Phytophthora cinnamomi has a world-wide distribution, causes disease in a very wide range of plants and is responsible for the destruction of certain plant communities in Europe and Australia. P. cinnamomi was probably introduced into Australia in the nineteenth century and is now established in south-western Australia and Tasmania, and throughout eastern Australia, from South Australia to the wet tropics. P. cinnamomi is listed as a Key Threatening Process under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999.

1 aDunstan, W A1 aHardy, G.E.St.J. uhttp://researchrepository.murdoch.edu.au/2427/04210nas a2200169 4500008004100000245012300041210006900164260001600233300001000249490000600259520359000265100002503855700001603880700002603896700002403922856009403946 2016 eng d00aAn overview of Australia’s Phytophthora species assemblage in natural ecosystems recovered from a survey in Victoria0 aoverview of Australia s Phytophthora species assemblage in natur cJan-01-2016 a47-580 v73 a

Although Phytophthora species cause serious diseases worldwide, until recently the main focus on disease in natural ecosystems in southern Australia has been on the distribution and impact of P. cinnamomi. However, new Phytophthora pathogens have emerged from natural ecosystems, and there is a need to better understand the diversity and distribution of these species in our natural forests, woodlands and heathlands. From a survey along a 70 km pipeline easement in Victoria, Phytophthora species were isolated from 249 rhizosphere samples and 25 bait bags deployed in 21 stream, river, or wetland locations. Of the 186 Phytophthora isolates recovered, 130 were identified to species based on ITS sequence data. Ninety-five isolates corresponded to 13 described Phytophthora species while additionally 35 isolates were identified as Clade 6 hybrids. Phytophthora cinnamomi was the most common species isolated (31 %), followed by P. elongata (6 %), both species were only recovered from soil. Samples from sites with the highest soil moisture at the time of sampling had the highest yield of isolates. Consistent with other studies throughout the world, Clade 6 species and their hybrids dominated water samples, although many of these species were also recovered less frequently from soil samples. Many of the species recovered in this study have not previously been reported from eastern Australia, reinforcing that Phytophthora species are widespread, abundant and diverse in natural ecosystems. We have probably been underestimating Phytophthora diversity in Australia.

1 aDunstan, William, A.1 aHoward, Kay1 aHardy, Giles, E. StJ.1 aBurgess, Treena, I. uhttp://www.ingentaconnect.com/content/ima/imafung/pre-prints/content-k4_Vol7_no1_Article402454nas a2200241 4500008004100000245010300041210006900144300001400213490000700227520172800234653001801962653002301980653002402003100001402027700001802041700001602059700001502075700001502090700001402105700001902119700001902138856005502157 2008 eng d00aPhytophthora pinifolia sp. nov. associated with a serious needle disease of Pinus radiata in Chile0 aPhytophthora pinifolia sp nov associated with a serious needle d a715–7270 v573 a

During the course of the past three years, a new disease of ,em>Pinus radiata, referred to as ‘Daño Foliar del Pino’ (DFP) has appeared in the Arauco province of Chile and subsequently spread to other areas. The disease is typified by needle infections, exudation of resin at the bases of the needle brachyblasts and, in younger trees, necrotic lesions in the cambium, which eventually girdle the branches. The disease causes the death of young seedlings and mature trees can also succumb after a few years of successive infection, probably hastened by opportunistic fungi such as ,em>Diplodia pinea. Isolations on selective medium for Phytophthora spp. led to the consistent isolation of a Phytophthora sp. from needle tissue. DNA sequence comparisons for the ITS rDNA and cox II gene regions, and morphological observation showed that this oomycete represents a previously undescribed species for which the name Phytophthora pinifolia sp. nov. is provided. This new species is characterized by unbranched sporangiophores, and non-papillate, sub-globose to ovoid sporangia that are occasionally free from the sporangiophore with medium length pedicels. Despite using a number of oospore inducing techniques, oogonia/antheridia were not observed in isolates of P. pinifolia. Pathogenicity trials with P. pinifolia showed that it is pathogenic to P. radiata and causes rapid death of the succulent apical parts of young plants. Phytophthora pinifolia is the first Phytophthora known to be associated with needles and shoots of a Pinus sp. and its aerial habit is well matched with the occurrence and symptoms of DFP in Chile.

10aMonterey pine10aoomycete phylogeny10aplantation forestry1 aDurán, A1 aGryzenhout, M1 aSlippers, B1 aAhumada, R1 aRotella, A1 aFlores, F1 aWingfield, B D1 aWingfield, M J uhttp://dx.doi.org/10.1111/j.1365-3059.2008.01893.x02221nas a2200241 4500008004100000245009100041210006900132300001100201490000800212520145200220653001801672653001401690653001801704653002101722100001901743700002201762700002401784700002101808700001801829700002501847700002601872856008101898 2009 eng d00aDNA-based method for rapid identification of the pine pathogen, Phytophthora pinifolia0 aDNAbased method for rapid identification of the pine pathogen Ph a99-1040 v2983 a

Phytophthora pinifolia causes a needle and shoot disease in Pinus radiata, referred to as ‘Daño Foliar del Pino’. This newly discovered disease requires intensive research efforts that necessitate the processing of large numbers of samples for which accurate identification, often by people not experienced in Phytophthora taxonomy, is required. The aim of this study was, therefore, to develop species-specific primers for P. pinifolia that amplify the internal transcribed spacer region of the ribosomal operon and the nuclear Ypt1 gene, respectively. The primers were tested over several Phytophthora spp., as well as fungi isolated from P. radiata. In all cases, only P. pinifolia was amplified. In addition to the species-specific primers, a PCR-restriction fragment length polymorphism protocol using available Phytophthora genus-specific primers was also used to generate a species-specific profile for P. pinifolia. This provided a characteristic profile that allows the identification of P. pinifolia, and it could also discriminate between 27 different species of Phytophthora. Both techniques reported in this study make it possible to identify large numbers of P. pinifolia cultures accurately and efficiently, which will be important for both quarantine work and biological research on this important new pathogen.

10aMonterey pine10aoomycetes10aPinus radiata10atree defoliation1 aDurán, Alvaro1 aSlippers, Bernard1 aGryzenhout, Marieka1 aAhumada, Rodrigo1 aDrenth, Andre1 aWingfield, Brenda, D1 aWingfield, Michael, J uhttp://onlinelibrary.wiley.com/doi/10.1111/j.1574-6968.2009.01700.x/abstract00707nas a2200205 4500008004100000022001400041245008100055210006900136300001400205490000800219653001800227100001900245700002400264700001900288700002200307700002100329700002500350700002600375856010000401 2010 eng d a1878-614600aAFLP analysis reveals a clonal population of Phytophthora pinifolia in Chile0 aAFLP analysis reveals a clonal population of Phytophthora pinifo a746 - 7520 v11410aPinus radiata1 aDurán, Alvaro1 aGryzenhout, Marieka1 aDrenth, AndrÈ1 aSlippers, Bernard1 aAhumada, Rodrigo1 aWingfield, Brenda, D1 aWingfield, Michael, J uhttp://www.sciencedirect.com/science/article/B9879-50GMMRW-1/2/c0c76996906d7b589f9430c65d0b2880