Submitted to: Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2000
Publication Date: N/A
Interpretive Summary: Molecular and genetic linkage maps are useful for plant breeding, genetic studies, and cloning genes of agricultural importance. Three low- resolution genetic maps have been constructed for oat. These maps were based on restriction fragment length polymorphisms (RFLP) and provided a foundation on which to pursue more targeted gene-discovery efforts. However, to effectively utilize current and future maps for positional cloning in oat, a significant increase in marker density is necessary. We established a highly saturated map with two new PCR-based marker systems, amplified fragment length polymorphisms (AFLPs) and sequence-specific amplification polymorphisms (S-SAP). A total of five hundred and thirteen markers were positioned on seven linkage groups, corrresponding to the seven basic chromosomes in oat, barley, wheat, and rye. These data will be deposited in the USDA-Graingenes database, creating a framework for public utilization. This is the first description of utilization of AFLP and retrotransposon-based S-SAP in the map construction for oat. The results described address the goals of National Program 302, Plant Biological and Molecular Processes, and will be useful in gene cloning, genetic mapping of qualitative genes, and positioning QTL of agricultural importance
Technical Abstract: A saturated map of diploid oat was constructed based on a recombinant inbred (RI) population developed from a cross between A. strigosa (C.I. 3815) and A. wiestii (C.I. 1994). This map includes 372 AFLP and 78 S-SAP markers, six crown-rust resistance genes, a cluster of resistance-gene analogs, one morphological marker, and is anchored by 45 grass-genome RFLP markers. This new A. strigosa x A. wiestii RI map is colinear with a diploid Avena map from an A. atlantica x A. hirtula F2 population. However, some linkage blocks were rearranged as compared to the RFLP map derived from the progenitor A. strigosa x A. wiestii F2 population. Clustering of markers led to the formation of highly saturated linkage blocks. Mapping of Bare-1-like sequences via sequence-specific AFLP indicated that related retrotransposons had considerable heterogeneity and widespread distribution in the diploid Avena genome. Novel amplified fragments detected in the RI population suggested that some of these retrotransposon-like sequences are active in diploid Avena. This framework map will be useful in gene cloning, genetic mapping of qualitative genes, and positioning QTL of agricultural importance.