Poster: Global change

Abs # 19: Gene Expression in Imbibed Brassic napus Seeds

Presenter:	Li, Fengling , fengling.li@nrc.ca
Authors	Li, Fengling  (A)   Wu, Xianzhong  (A)   Tsang, Ed  (A)   Cutler, Adrian  (A)
Affiliations:	(A): Plant Biotechnology Institute, National Research Council Canada

Yields of canola crops are dependent upon rapid and uniform seed germination. However, under sub-optimal growth conditions, imbibed seeds may not germinate and in some cultivars may subsequently become dormant. The decision point that determines whether imbibed seeds proceed to germination is subject to very precise regulation, the complexity of which originates both from environmental factors and from inherent seed properties. Our goals are to understand mRNA-level regulation of germination in Brassica napus and the differences between germinating and non-germinating seeds. The approach utilizes Arabidopsis cDNA microarrays to compare gene expression profiles in normally germinating seeds of Brassica napus with seeds in which germination is blocked either by water stress, imposed by polyethylene glycol-8000 (PEG), or by ABA analog PBI 429 (methyl 8’-acetylene abscisate) that is longer lasting and more active than ABA. Microarrays were hybridized with dye-labeled cDNA from seed following different times (6-48 hours) of PEG and PBI 429 treatments. Results for selected genes have been independently validated by Northern analysis. A summary of the comparisons will be presented.