Download 2559 P Ramsfield

2005 IUFRO World Congress
Title: The development of a DNA based detection system for western gall rust
Author: Tod D. Ramsfield, Forest Research, Private Bag 3020, Rotorua, New Zealand.
Detlev R. Vogler, Institute of Forest Genetics, USDA Forest Service, Placerville, CA,
USA.
Abstract Text: Western gall rust (Peridermium harknessii syn. Endocronartium
harknessii) is a serious threat to exotic Pinus radiata forests in New Zealand. As the
pathogen is not present in New Zealand and because of the long period of time between
infection and spore production, a DNA based marker has been developed that is able to
detect the presence of pathogen DNA within galled tissue prior to sporulation. Initially,
the DNA based system was targeted at the internal transcribed spacer region of the
ribosomal DNA and a marker was developed that could detect western gall rust within
Pinus radiata but the marker could not distinguish P. harknessii from its close relative
Cronartium quercuum. In order to increase the specificity of the marker system, the
intergenic spacer region of the ribosomal DNA of E. harknessii and all four formae
specialis of C. quercuum was sequenced and compared. This allowed the development of
a marker system that was able to distinguish E. harknessii from all C. quercuum formae
specialis with the exception of C. quercuum f. sp. banksianae. IGS sequence alignment
has been used to construct a phylogeny to compare P. harknessii and C. quercuum. (190
words).
Preferred Format: Poster Presentation
Suggested Session: # 040: Alien pests threatening biodiversity of forest ecosystems