02555nas a2200217 4500008004100000022001400041245011100055210006900166300001200235490000700247520187500254653001602129653002302145653001802168100002202186700001702208700002302225700002602248700002502274856003802299 2010 eng d a0815-319100aPhytophthora elongata sp. nov., a novel pathogen from the Eucalyptus marginata forest of Western Australia0 aPhytophthora elongata sp nov a novel pathogen from the Eucalyptu a477-4910 v393 a

A novel homothallic species of Phytophthora producing semipapillate sporangia on sympodially branching sporangiophores, thick-walled oospores in smooth-walled oogonia, and paragynous antheridia is described here as Phytophthora elongata sp. nov. DNA sequencing of the internal transcribed spacer (ITS) DNA and coxI gene confirm P. elongata as a distinct species within ITS clade 2. It has been isolated in the northern jarrah forest of Western Australia (WA) from the roots and collars of dead and dying Eucalyptus marginata and occasionally Corymbia calophylla in rehabilitated bauxite mine pits. It has also been associated with dead and dying plants of several mid- and understorey species in the northern and southern jarrah forest—Banksia grandis, Leucopogon propinquus, Dryandra squarrosa and an Andersonia sp., as well as the monocotyledonous Xanthorrhoea preissii, X. gracilis and Patersonia xanthina. P. elongata has also been isolated from sandy soils and loams in Victoria in eastern Australia. The pathogenicity of P. elongata to E. marginata and Banksia spp. has been shown in this and earlier studies. Due to the uniformity of the ITS DNA and cox 1 sequence data in WA, P. elongata may be the result of a recent clonal introduction. More pathogenicity tests on a wider range of native plant species are needed to assess the host range of P. elongata and its invasive potential in WA.

10abiosecurity10anatural ecosystems10aphylogenetics1 aRea, Alexander, J1 aJung, Thomas1 aBurgess, Treena, I1 aStukely, Michael, J C1 aHardy, Giles St, E J uhttp://dx.doi.org/10.1071/AP10014