© 1997 Heron Publishing—Victoria, Canada
Analysis of bark proteins in blister rust-resistant and susceptible western white pine (Pinus monticola)
Joanne Davidson (1, 2) and Abul K. M. Ekramoddoullah (1)
1. Canadian Forest Service, Pacific Forestry Centre, 506 West Burnside Road, Victoria, British Columbia V8Z 1M5, Canada / 2. University of Victoria, Centre for Forest Biology, Victoria, British Columbia V8W 3P2, Canada / Received September 24, 1996
Summary
We compared bark proteins from four contrasting (blister rust-resistant versus susceptible) half-sib seedling pairs of western
white pine (Pinus monticola D. Don). Pooled proteins from resistant and susceptible groups (four trees per group) were separated by two-dimensional gel
electrophoresis, silver stained, and analyzed with the aid of a laser scanner interfaced with a computerized gel documentation
system.
Qualitative and quantitative protein differences were observed between resistant and susceptible groups. The number of proteins
unique to a group was greater in the susceptible category than in the resistant category. Biosynthesis of some common proteins
was enhanced near lesioned areas of susceptible seedlings. Many proteins shared similar charge and mass characteristics with
those of pathogenesis-related (PR) proteins. Two protein bands were isolated and partially characterized by N-terminal amino
acid sequencing: a 10.6-kDa band that was selectively enriched in all resistant individuals, and a 26.0-kDa band that was
enriched in some susceptible individuals. The significance of these protein differences and the possible use of selected proteins
as disease or resistance markers are discussed.
Keywords:
Cronartium ribicola, disease markers, pathogenesis-related proteins, resistance markers, slow canker growth.
