Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/13/2005
Publication Date: 1/14/2006
Citation: Cruz, V., Luhman, R., Rife, C.L., Shoemaker, R.C., Marek, L.F., Brummer, E.C., Gardner, C.A. 2006. Characterization of flowering time and ssr marker analysis of annual and winter type brassica napus germplasm [abstract]. Plant and Animal Genome VX Conference. Poster Presentation P144. Interpretive Summary:
Technical Abstract: The flowering time and life forms of all Brassica napus accessions conserved at the North Central Regional Plant Introduction Station (NCRPIS) were characterized and a survey of molecular variation was conducted using simple sequence repeats (SSR). To characterize flowering time, 598 accessions comprising the entire collection of B. napus were planted in Iowa and Kansas field sites and observed for days to flowering (1st, 50% and 100% flowering). Days from planting to 50% flowering ranged from 31 to 83 in Iowa and from 42 to 89 in Kansas. Flowering time between locations was significantly correlated, although differences in flowering time rank were observed for several accessions. Accessions that failed to flower in a single growing season comprised 30% of the B. napus collection. Not all plants of an accession flowered, so 100% flowering was not always achieved. Accessions were classified according to flowering time in six groups. From these groups, fifty were selected for marker analysis including 10 non-flowering and 40 flowering accessions that were of diverse geographic origins and observed variation in flowering dates. Thirty SSR markers selected across 18 Brassica linkage groups from BrassicaDB, and three derived from Brassica expressed sequence tags (ESTs) were used. An average of three alleles per locus was observed. Analysis of molecular variation using cluster analysis and ordination resulted in recognizable, distinct groups of annual and biennial plant life form types.