Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/13/2002
Publication Date: 1/11/2003
Citation: Gu, X., Foley, M.E. 2003. Identification of quantitative trait loci controlling seed dormancy in weedy rice (Oryza sativa). [Abstract]. Plant and Animal Genome XI. Page No. 156. Interpretive Summary:
Technical Abstract: Seed dormancy contributes to adaptability of wild species, arrests development of the plant, and is a key factor in crop domestication. Our research has determined that seed dormancy is much stronger and heritability for the trait is higher in most weedy rice strains as compared with that in dormant cultivars. A very dormant weedy strain, `SS18-2', was selected to identify quantitative trait loci (QTLs) for hull-imposed seed dormancy under controlled conditions. The mapping population consisted of 160 BC1F1 individuals with a non-dormant, extremely early maturation breeding line, `EM93-1', as the recurrent parent. Each BC1F1 individual was split into four tillering-plants at the late seedling stage for replication of the phenotypic assay. The assay, which utilizes freshly harvested and partially after-ripened seeds, is conducted using standard germination methods of 30 C for 7 days. Simple sequence repeat (SSR) markers are used to construct a framework genetic map. To date, seventy-five markers distributed over the 12 chromosomes using a subgroup (96 BC1F1 plants) of the population. We are screening for more polymorphic DNA markers to close the gaps and to identify genotypes of the remaining BC1F1 individuals. The map and result from the QTL analysis will be presented.