AUTHOR=Liu Jia , Wang Wenxiang , Mei Desheng , Wang Hui , Fu Li , Liu Daoming , Li Yunchang , Hu Qiong 

TITLE=Characterizing Variation of Branch Angle and Genome-Wide Association Mapping in Rapeseed (Brassica napus L.)

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.00021

DOI=10.3389/fpls.2016.00021

ISSN=1664-462X

ABSTRACT=<p>Changes in the rapeseed branch angle alter plant architecture, allowing more efficient light capture as planting density increases. In this study, a natural population of rapeseed was grown in three environments and evaluated for branch angle trait to characterize their phenotypic patterns and genotype with a 60K <italic>Brassica</italic> Infinium SNP array. Significant phenotypic variation was observed from 20 to 70°. As a result, 25 significant quantitative trait loci (QTL) associated with branch angle were identified on chromosomes A2, A3, A7, C3, C5, and C7 by the MLM model in TASSEL 4.0. Orthologs of the functional candidate genes involved in branch angle were identified. Among the key QTL, the peak SNPs were close to the key orthologous genes <italic>BnaA.Lazy1</italic> and <italic>BnaC.Lazy1</italic> on A3 and C3 homologous genome blocks. With the exception of Lazy (<italic>LA</italic>) orthologous genes, <italic>SQUMOSA PROMOTER BINDING PROTEIN LIKE 14</italic> (<italic>SPL14</italic>) and an auxin-responsive <italic>GRETCHEN HAGEN 3</italic> (<italic>GH3</italic>) genes from <italic>Arabidopsis thaliana</italic> were identified close to two clusters of SNPs on the A7 and C7 chromosomes. These findings on multiple novel loci and candidate genes of branch angle will be useful for further understanding and genetic improvement of plant architecture in rapeseed.</p>