Published in Probe Volume 2(1): Spring 1992
Dr. W. K. Kim and Dr. T. F.
Townley-Smith
Agriculture Canada Research Station-Winnipeg
Manitoba, Canada
Canadian researchers have increased their networking capability and strengthened communication with each other as a result of establishing the Canada Wheat Genome Mapping Group.
The scientists formed the Group in Winnipeg in February 1990 when the RFLP Workshop-Agriculture Canada BioCrop Network convened in conjunction with the Canada Expert Committee on Plant Breeding and Plant Disease. At the discussion session of the Cereals RFLP Syndicate, participants selected two coordinators for the Group, Drs. Won K. Kim and N.K. Howes of the Agriculture Canada Winnipeg Research Station.
Rather than initiate wheat RFLP mapping immediately, the Group decided to focus on the application of the technology (for example, the use of PCR and barley probes to wheat; support of barley initiatives of the North America Barley Genome Mapping Project; and the use of available probes to tag smut and bunt resistance, and high protein genes).
Group Membership
Currently, there are 34 individual members with the following interests: RFLP Mapping, 6; Cytogenetics (includes in situ hybridization and development of double-haploids), 5; Genetic Analysis and Field Tests (agronomic and disease evaluation), 19; Molecular Biology, 2; and Quality Tests, 2.
Canadian research establishments that have a cereal biotechnology program on-site are involved in the mapping effort. Participating institutions are: The Plant Research Centre, Agriculture Canada, Ottawa; the Winnipeg Research Station; the Lethbridge Research Station; the University of Guelph; and the University of Saskatchewan. Some members of these establishments serve on the recently organized Steering Committee.
In February the Group held a Genome Mapping Workshop in Saskatoon, Saskatchewan, at the Canada Expert Committee meeting. Once the Group's mandate and genetic resources are identified for the mapping effort, more research institutions are expected to participate.
Winnipeg's RFLP Analysis
One project of the Winnipeg Research Station is the RFLP analysis of wheat and barley genomes. Coordinated by Dr. Kim and Dr. T.F. Townley-Smith, the project's objective is to identify genes for rust, smut, and sprouting resistance. These are the integral components of the Station's cereal cultivar development program.
RAPD (random amplified polymorphic DNA) primers (arbitrary nucleotide sequence) are now widely used to amplify the genomic DNA by PCR and to detect polymorphism among cereal cultivars. These findings can be used as genetic markers and to construct genetic maps. Researchers are in the process of screening 400 RAPD primers that were synthesized by the University of British Columbia Biotechnology Centre staff. Of 150 screened, researchers found 41 polymorphic primers in barley and 35 in wheat. The following cereal cultivars are used for the genetic analysis with selected RAPD markers:
Barley (in collaboration with Dr. P.L. Thomas)--Researchers use Hannchen (2 row) with covered smut resistance gene and Plush (6 row) with covered smut resistance gene. (These two genes are not linked.) Nineteen RAPD markers are in analysis, using F6 recombinant inbred lines. Sixty of 100 single seed descent lines were screened for disease reaction.
Wheat (in collaboration with Dr. N.K. Howes and Mr. R. Knox)--Researchers are interested in tagging a bunt resistance gene and a sprouting resistance gene. A wheat germplasm RL 4555 (soft, white, sprouting resistance gene) x Biggar BSR (bunt resistance gene bt-10 (derived from BW553)) and smut resistance gene (derived from Glenlea). We have F3 single seed descent lines for analysis, using 15 RAPD markers.
Wheat (in collaboration with Mr. E. Czarnecki)--Researchers are interested in mapping a bunt resistance gene and finding DNA markers that would detect polymorphism. Wheat cultivar Roblin x BW 553, BC3 F2, and BC3 F5 are now available for RAPD analysis. Researchers also found polymorphism between these materials when ribosomal DNA repeat unit was restricted with Bam H1 and probed with pMF2 (ribosomal RNA genes of Neurospora crassa).
For cereal DNA analysis at the Station, researchers identified several useful parental lines: RL 4555 (soft, white, sprouting resistance gene); Biggar BSR (bt 10, bunt resistance gene and smut resistance gene); Chinese Spring Sr 6 (stem rust resistance gene); BW 121 (streak mosaic virus resistance gene); Timgalen (Australian germplasm, stem rust resistance genes, Sr 5, Sr 6, Sr 8, Sr Tt), and Sr T (Australian wheat cultivars by CSIRO, 1975). The mapping populations would include single seed descent and double-haploids.
Related Research
Other related research includes Ribosomal DNA repeat unit polymorphism in 27
accessions of six species of Aegilops (in collaboration with Dr. E.R.
Kerber
and Mr. B. Innes). Species of the genus Aegilops are important
sources of
useful alien genes in developing wheat cultivars with disease and insect
resistance, and cold hardiness. In an effort to understand the genetic
diversity amony several species, the ribosomal RNA genes were double-digested
with Bam HI and Eco RI. Researchers found that two accessions of
Ae.squarrosa
var.strangulata (collected from Turkmenia and Azerbaijan, former USSR)
had two
additional Bam HI sites in the non-transcribed spacer region in addition to two
sites in the coded regions.
Contact for Information
For more information on the Canada Wheat Genome Mapping Group and the genetic
material currently under investigation, please write to Dr. Won K. Kim,
Agriculture Canada Research Station, Winnipeg, Manitoba, Canada R3T2M9; Ph.
(204) 983-5533 or 983-2340; FAX (204) 983-4604.