@article {4485, title = {Diversity of Phytophthora species in natural ecosystems of Taiwan and association with disease symptoms}, journal = {Plant Pathology}, volume = {66}, year = {2017}, month = {Jan-07-2016}, pages = {194{\textendash}211}, abstract = {

In 2013 a survey of Phytophthora diversity was performed in 25 natural and seminatural forest stands and 25 rivers in temperate montane and subtropical lowland regions of Taiwan. Using baiting assays, 10 described species and 17 previously unknown taxa of Phytophthora were isolated from 71.5\% of the 144 rhizosphere soil samples from 33 of 40 tree species sampled in 24 forest stands, and from 19 rivers: P.\ capensis, P.\ citrophthora, P.\ plurivora, P.\ tropicalis, P.\ citricola VII, P.\ sp.\ {\texttimes}\ botryosa-like, P.\ sp.{\texttimes}\ meadii-like and P.\ sp. occultans-like from Clade 2; P.\ palmivora from Clade 4; P.\ castaneae and P.\ heveae from Clade 5; P.\ chlamydospora and P.\ sp. forestsoil-like from Clade 6; P.\ cinnamomi (Pc), P.\ parvispora, P.\ attenuata nom. prov., P.\ flexuosa nom. prov., P.\ formosa nom. prov., P.\ intricata nom. prov., P.\ {\texttimes}\ incrassata nom. prov. and P.\ {\texttimes}\ heterohybrida nom. prov. from Clade 7; P.\ sp. palustris and five new hybrid species from Clade 9. The A1 mating type of Pc was widespread in both montane and lowland forests and rarely associated with disease, whereas the A2 mating type was limited to lowland forests and in some cases causing severe dieback. Most other Phytophthora species were not associated with obvious disease symptoms. It is concluded that (i) Taiwan is within the centre of origin of most Phytophthora taxa found, (ii) Pc A2 is an introduced invasive pathogen, and (iii) interspecific hybridizations play a major role in speciation and species radiations in diverse natural ecosystems.

}, doi = {10.1111/ppa.12564}, url = {http://doi.wiley.com/10.1111/ppa.12564http://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111\%2Fppa.12564}, author = {Jung, T. and Chang, T. T. and Bakonyi, J. and Seress, D. and P{\'e}rez-Sierra, A. and Yang, X. and Hong, C. and Scanu, B. and Fu, C. H. and Hsueh, K. L. and Maia, C. and Abad-Campos, P. and Le{\'o}n, M. and Horta Jung, M.} } @article {4657, title = {Multiple new Phytophthora species from ITS Clade 6 associated with natural ecosystems in Australia: evolutionary and ecological implications}, journal = {Persoonia - Molecular Phylogeny and Evolution of Fungi}, volume = {26}, year = {2011}, month = {Jun-06-2013}, pages = {13 - 39}, abstract = {

During surveys of dying vegetation in natural ecosystems and associated waterways in Australia many new taxa have been identified from Phytophthora ITS Clade 6. For representative isolates, the region spanning the internal transcribed spacer region of the ribosomal DNA, the nuclear gene encoding heat shock protein 90 and the mitochondrial cox 1 gene were PCR amplified and sequenced. Based on phylogenetic analysis and morphological and physiological comparison, four species and one informally designated taxon have been described; Phytophthora gibbosa, P. gregata, P. litoralis, P. thermophila and P. taxon paludosa. Phytophthora gibbosa, P. gregata and P. taxon paludosa form a new cluster and share a common ancestor; they are homothallic and generally associated with dying vegetation in swampy or water-logged areas. Phytophthora thermophila and P. litoralis are sister species to each other and more distantly to P. gonapodyides. Both new species are common in waterways and cause scat tered mortality within native vegetation. They are self-sterile and appear well adapted for survival in an aquatic environment and inundated soils, filling the niche occupied by P. gonapodyides and P. taxon salixsoil in the northern hemisphere. Currently the origin of these new taxa, their pathogenicity and their role in natural ecosystems are unknown. Following the precautionary principle, they should be regarded as a potential threat to native ecosystems and managed to minimise their further spread.

}, issn = {00315850}, doi = {10.3767/003158511X557577}, url = {http://www.ingentaconnect.com/content/nhn/pimj/2011/00000026/00000001/art00002}, author = {Jung, T. and Stukely, M.J.C. and Hardy, G.E.St.J. and White, D. and Paap, T. and Dunstan, W.A. and Burgess, T.I.} } @article {4656, title = {Phytophthora root and collar rot of alders in Bavaria: distribution, modes of spread and possible management strategies}, journal = {Plant Pathology}, volume = {53}, year = {2004}, month = {Jan-04-2004}, pages = {197 - 208}, abstract = {

A survey of symptoms of phytophthora root and collar rot of common (Alnus glutinosa) and grey alder (A. incana) in riparian and forest stands in Bavaria was conducted by the Bavarian State Forestry and river authorities. Symptoms were seen in 1041 out of 3247 forest alder stands. The majority of the affected stands (80{\textperiodcentered}9\%) were less than 21\ years old; 46\% of these young stands were growing on nonflooded sites and 92\% had been planted. The riparian survey showed that symptoms were widespread along more than 50\% of the river systems. Along some rivers the disease incidence exceeded 50\%. The {\textquoteleft}alder Phytophthora{\textquoteright} was recovered from 166 of 185 riparian and forest alder stands with symptoms. In 58 of the 60 rivers and streams investigated in detail, the source of inoculum was traced back to infested young alder plantations growing on the river banks or on forest sites that drain into the rivers. Once introduced to a river system, the {\textquoteleft}alder Phytophthora{\textquoteright} infects alders downstream. Baiting tests showed that the {\textquoteleft}alder Phytophthora{\textquoteright} was present in rootstocks of alders from three out of four nurseries which regularly bought in alder plants for re-sale, but not in rootstocks from four nurseries that grew their own alders from seed. In addition, the infected nurseries used water from infested water courses for irrigation. The Bavarian State Ministry for Agriculture and Forestry has developed a code of practice for producing healthy alder plants in forest nurseries. This includes a 3-year fallow period between bare-rooted alder crops because of poor survival of the {\textquoteleft}alder Phytophthora{\textquoteright} in soil.

}, issn = {0032-0862}, doi = {10.1111/j.0032-0862.2004.00957.x}, url = {http://doi.wiley.com/10.1111/j.0032-0862.2004.00957.x}, author = {Jung, T. and Blaschke, M.} } @article {4610, title = {Canker and decline diseases caused by soil- and airborne Phytophthora species in forests and woodlands}, journal = {Persoonia - Molecular Phylogeny and Evolution of Fungi}, volume = {40}, year = {2018}, month = {Jan-01-2018}, pages = {182-220}, abstract = {

Most members of the oomycete genus Phytophthora are primary plant pathogens. Both soil- and airborne Phytophthora species are able to survive adverse environmental conditions with enduring resting structures, mainly sexual oospores, vegetative chlamydospores and hyphal aggregations. Soilborne Phytophthora species infect fine roots and the bark of suberized roots and the collar region with motile biflagellate zoospores released from sporangia during wet soil conditions. Airborne Phytophthora species infect leaves, shoots, fruits and bark of branches and stems with caducous sporangia produced during humid conditions on infected plant tissues and dispersed by rain and wind splash. During the past six decades, the number of previously unknown Phytophthora declines and diebacks of natural and semi-natural forests and woodlands has increased exponentially, and the vast majority of them are driven by introduced invasive Phytophthora species. Nurseries in Europe, North America and Australia show high infestation rates with a wide range of mostly exotic Phytophthora species. Planting of infested nursery stock has proven to be the main pathway of Phytophthora species between and within continents. This review provides insights into the history, distribution, aetiology, symptomatology, dynamics and impact of the most important canker, decline and dieback diseases caused by soil- and airborne Phytophthora species in forests and natural ecosystems of Europe, Australia and the Americas.

}, issn = {0031-5850}, doi = {10.3767/persoonia.2018.40.08}, url = {http://www.ingentaconnect.com/content/nhn/pimj/10.3767/persoonia.2018.40.08}, author = {Jung, T. and P{\'e}rez-Sierra, A. and Dur{\'a}n, A. and Horta Jung, M. and Balci, Y. and Scanu, B.} }