@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 {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.} }