Sam Hendricks, Wendy Sutton and Jeffrey Stone, Oregon State University, Dept. of Botany and
Plant Pathology, Corvallis, OR; Richard Sniezko and Angelia Kegley, USDA Forest Service, Dorena
Genetic Resources Center, Cottage Grove, OR; and Anna Schoettle, USDA Forest Service, Rocky Mountain
Abstract
Polymerase Chain Reaction (PCR) Applications in
White Pine Blister Rust Resistance Screening
Research Station, Fort Collins, CO
Abstract—A goal of breeding programs for resistance to white
pine blister rust is the development of multigenic resistance, even
if the genetics and mechanisms of resistance may be imperfectly
understood. The goal of multigenic resistance has prompted efforts
to categorize host resistance reactions at increasingly finer scales,
to identify heritable traits that may confer quantitative resistance.
PCR amplification of Cronartium ribicola DNA presents a sensitive
and highly specific method for detection of C. ribicola in host tissues, and is well suited to screening of large numbers of samples for
which other methods of pathogen detection (e.g., microscopy) may
be unsuitable. PCR amplification can be used to detect presence of
the pathogen in different host tissues, and so can provide useful information on putatative resistance responses that may be localized
in specific tissue types. We report development of a PCR based
assay for detection of C. ribicola in pine needle tissue and the results of PCR screening for C. ribicola in limber pine and whitebark
pine individuals that have been identified as having as yet uncharcterized resistance responses that prevent or impair colonization in
needle, shoot, root and bark tissues, and discuss the advantages of
this method in operational breeding programs. PCR amplification
detected C. ribicola in symptomatic regions of western white pine,
whitebark pine and limber pine needles at 6 months after inoculation; C. ribicola was detected in the nonsymptomatic region of only
one of six infected needles tested. Work is continuing to improve
the sensitivity of the technique.
The content of this paper reflects the views of the author(s), who are
responsible for the facts and accuracy of the information presented
herein.
In: Keane, Robert E.; Tomback, Diana F.; Murray, Michael P.; and Smith, Cyndi M., eds. 2011. The future of high-elevation, five-needle white pines in Western North
USDA
Forest
Service
Proceedings
RMRS-P-63.
America:
Proceedings
of the
High Five Symposium.
28-30 2011.
June 2010; Missoula, MT. Proceedings RMRS-P-63. Fort Collins, CO: U.S. Department of Agriculture,
Forest Service, Rocky Mountain Research Station. 376 p. Online at http://www.fs.fed.us/rm/pubs/rmrs_p063.html
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