Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: February 1, 1996
Publication Date: N/A
A core set of 302 Recombinant Inbred Lines (RILs) has been developed from 'Lemont'/'Teqing' to serve as a "permanent" rice gene-mapping population. Seed is being shared and data on 120 RFLPs will be made publicly available via RiceGenes on the Internet. This is the first rice mapping population suitable for study in rice-growing regions of the U.S. and offers the chance to economically map genes for any character found to be segregating Transgressive segregation has been observed for each character measured to date, including some where the parents are not apparently different. A portion of the RILs and the parental lines should be observed when evaluating the population's suitability for mapping a character. This population has more lines, less severe sterility, and less genetic skewness than other available mapping populations, allowing identification of genes with smaller effect. Lessons learned while developing this mapping population include: a) select a widely compatible parent if possible, b) avoid environments that increase outcrossing, c) most of the phenotypic variance observed in F6 and later generations was attributable to mixture rather than heterozygosity - replication is imperative and panicle bagging may be limited to highly sterile lines, d) interpret QTL analyses from biological and technical viewpoints, e) skewing and natural selection will occur - document it and account for it in data interpretations, f) mapping multiple traits simultaneously can elucidate relationships between them, g) take advantage of unexpected segregation, h) use Dr. McCouch's "Anchor" probes if possible. In earlier, segregating generations of this population, we identified and located QTLs for several characters. We will use these RILs to better define the QTLs before attempting Marker Assisted Selection.