TY - JOUR
T1 - Phytophthora pseudosyringae sp. nov., a new species causing root and collar rot of deciduous tree species in Europe
AU - Jung, Thomas
AU - Nechwatal, Jan
AU - Cooke, David E.L.
AU - Hartmann, Günther
AU - Blaschke, Markus
AU - Oßwald, Wolfgang F.
AU - Duncan, James M.
AU - Delatour, Claude
N1 - Funding Information:
We are grateful to the Bavarian State Ministry for Agriculture and Forestry (Projects F44 and F45), the Allianz Stiftung zum Schutz der Umwelt, the European Union (Project ‘Pathoak’ FAIR 5-CT97-3926), and The Scottish Executive Environment and Rural Affairs Department for the generous financial support. The authors would also like to thank Evelyn Kitta, Alexandra Nannig, Renate Bernhard, Johanna Lebherz and Naomi Williams for their assistance in the laboratory routines. We are also grateful to Clive M. Brasier (Forestry Research, Farnham), Everett Hansen (Oregon State University, Corvallis) and Helmut Blaschke (Department of Ecology, Freising, Germany) for constructive discussions. The isolates at SCRI were held under licence PH/27/2003.
PY - 2003/7/1
Y1 - 2003/7/1
N2 - In several studies of oak decline in Europe, a semi-papillate homothallic Phytophthora taxon was consistently isolated, together with other Phytophthora species, from rhizosphere soil samples. It was also found associated with necrotic fine roots and stem necroses of Fagus sylvatica and Alnus glutinosa. Due to morphological and physiological similarities, the semi-papillate isolates were previously identified as P. syringae by various authors. The morphology, physiology and pathogenicity against fine roots of Quercus robur, Q. petraea and F. sylvatica, bark of A. glutinosa, leaves of Ilex aquifolium and apple fruits of this Phytophthora species are described and compared with those of related and similar Phytophthora species, namely P. ilicis, P. psychrophila, P. quercina, P. citricola and P. syringae. The phylogenetic placement on the basis of ITS and mtDNA sequence data was also examined. Isolates of this taxon produce colonies with stellate to rosaceous growth patterns and limited aerial mycelium on various agar media. Antheridia are predominantly paragynous. In water culture catenulate hyphal swellings and semi-papillate caducous sporangia, that are usually limoniform, ellipsoid or ovoid, are formed abundandly, mostly in lax or dense sympodia. This taxon is a moderately slow growing, low temperature species with optimum and maximum temperatures around 20 and 25°C, respectively. Tested isolates are moderately aggressive to fine roots of oaks and beech, highly aggressive to holly leaves and apple fruits, and slightly pathogenic to alder bark. Thirteen tested isolates had an identical and distinct ITS sequence which was more similar to that of P. ilicis and P. psychrophila than any other known taxa. On the basis of their unique combination of morphological characters, colony growth patterns, cardinal temperatures for growth, growth rates, pathogenicity to oaks, beech, alder, apple and holly, their host range, and ITS and mtDNA sequences the semi-papillate caducous Phytophthora isolates from oaks, beech and alder are clearly separated from related and similar Phytophthora spp., and described as a new species, P. pseudosyringae sp. nov.
AB - In several studies of oak decline in Europe, a semi-papillate homothallic Phytophthora taxon was consistently isolated, together with other Phytophthora species, from rhizosphere soil samples. It was also found associated with necrotic fine roots and stem necroses of Fagus sylvatica and Alnus glutinosa. Due to morphological and physiological similarities, the semi-papillate isolates were previously identified as P. syringae by various authors. The morphology, physiology and pathogenicity against fine roots of Quercus robur, Q. petraea and F. sylvatica, bark of A. glutinosa, leaves of Ilex aquifolium and apple fruits of this Phytophthora species are described and compared with those of related and similar Phytophthora species, namely P. ilicis, P. psychrophila, P. quercina, P. citricola and P. syringae. The phylogenetic placement on the basis of ITS and mtDNA sequence data was also examined. Isolates of this taxon produce colonies with stellate to rosaceous growth patterns and limited aerial mycelium on various agar media. Antheridia are predominantly paragynous. In water culture catenulate hyphal swellings and semi-papillate caducous sporangia, that are usually limoniform, ellipsoid or ovoid, are formed abundandly, mostly in lax or dense sympodia. This taxon is a moderately slow growing, low temperature species with optimum and maximum temperatures around 20 and 25°C, respectively. Tested isolates are moderately aggressive to fine roots of oaks and beech, highly aggressive to holly leaves and apple fruits, and slightly pathogenic to alder bark. Thirteen tested isolates had an identical and distinct ITS sequence which was more similar to that of P. ilicis and P. psychrophila than any other known taxa. On the basis of their unique combination of morphological characters, colony growth patterns, cardinal temperatures for growth, growth rates, pathogenicity to oaks, beech, alder, apple and holly, their host range, and ITS and mtDNA sequences the semi-papillate caducous Phytophthora isolates from oaks, beech and alder are clearly separated from related and similar Phytophthora spp., and described as a new species, P. pseudosyringae sp. nov.
UR - http://www.scopus.com/inward/record.url?scp=0041423446&partnerID=8YFLogxK
U2 - 10.1017/S0953756203008074
DO - 10.1017/S0953756203008074
M3 - Article
C2 - 12967204
AN - SCOPUS:0041423446
SN - 0953-7562
VL - 107
SP - 772
EP - 789
JO - Mycological Research
JF - Mycological Research
IS - 7
ER -