Abstract
Using advanced intermated populations has been proposed as a way to increase the accuracy of mapping experiments. An F(3) population of 300 lines and an advanced intermated F(3) population of 322 lines, both derived from the same parental maize inbred lines, were jointly evaluated for dry grain yield (DGY), grain moisture (GM), and silking date (SD). Genetic variance for dry grain yield was significantly lower in the intermated population compared to the F(3) population. The confidence interval around a QTL was on average 2.31 times smaller in the intermated population compared to the F(3) population. One controversy surrounding QTL mapping is whether QTL identified in fact represent single loci. This study identifies two distinct loci for dry grain yield in the intermated population in coupling phase, while the F(3) identifies only a single locus. Surprisingly, fewer QTL were detected in the intermated population than the F(3) (21 vs. 30) and <50% of the detected QTL were shared among the two populations. Cross-validation showed that selection bias was more important in the intermated population than in the F(3) and that each detected QTL explained a lower percentage of the variance. This finding supports the hypothesis that QTL detected in conventional populations correspond mainly to clusters of linked QTL. The actual number of QTL involved in the genetic architecture of complex traits may be substantially larger, with effect sizes substantially smaller than in conventional populations.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.