Genetic Survey of a Canadian Collection of Brassica napus Breeding Lines and Germplasm

The development of canola (low erucic acid, low glucosinolate) from rapeseed and subsequent improvement of the crop for the Canadian prairies over the past 60 years is largely represented by collections of breeding material at Agriculture and Agri-Food Canada (AAFC).  Loss of allelic diversity had previously been shown to have occurred in the development of canola from summer rapeseed in cultivars released from the AAFC breeding program in the early 1990s.  It was suggested that heterogenic historic landraces and older varieties used in the development of canola may be a valuable source of variability that could be used to broaden the Canadian B. napus genepool.  Over the past 20 years, the development of various unique quality traits (high stability oil, low saturated fat) and yellow seeded canola gene pools has been achieved at AAFC using an array of breeding methods and varied sources of diversity.  In the current study, the allelic diversity of canola breeding collections and current breeding lines are being assessed using simple sequence repeat markers distributed over the B. napus genome.  Comparison of the diversity and relatedness of current breeding material to older collections may help identify unique sources of variability that can be assessed for agronomic performance and quality traits and subsequently be used in cultivar improvement.  Furthermore, monitoring diversity within current breeding material will provide a template for assessing heterotic potential between lines as well as minimizing genetic erosion within Canadian germplasm.