Open AccessA novel quantitative trait locus on chromosome A9 controlling oleic acid content in Brassica napus
Author(s) -
Zhao Qing,
Wu Jian,
Cai Guangqin,
Yang Qingyong,
Shahid Muhammad,
Fan Chuchuan,
Zhang Chunyu,
Zhou Yongming
Publication year - 2019
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.13142
Subject(s) - biology , quantitative trait locus , brassica , genetics , locus (genetics) , candidate gene , gene , allele , population , genetic linkage , marker assisted selection , horticulture , demography , sociology
Summary One of the most important goals in the breeding of oilseed crops, including Brassica napus , is to improve the quality of edible vegetable oil, which is mainly determined by the seed fatty acid composition, particularly the C18:1 content. Previous studies have indicated that the C18:1 content is a polygenic trait, and no stable quantitative trait loci ( QTL s) except for FAD 2 have been reported. By performing a GWAS using 375 low erucic acid B. napus accessions genotyped with the Brassica 60K SNP array and constructing a high‐density SNP ‐based genetic map of a 150 DH population, we identified a novel QTL on the A9 chromosome. The novel locus could explain 11.25%, 5.72% and 6.29% of phenotypic variation during three consecutive seasons and increased the C18:1 content by approximately 3%–5%. By fine mapping and gene expression analysis, we found three potential candidate genes and verified the fatty acids in a homologous gene mutant of Arabidopsis. A metal ion‐binding protein was found to be the most likely candidate gene in the region. Thus, the C18:1 content can be further increased to about 80% with this novel locus together with FAD 2 mutant allele without compromise of agronomic performance. A closely linked marker, BnA129, for this novel QTL ( OLEA 9 ) was developed so that we can effectively identify materials with high C18:1 content at an early growth stage by marker‐assisted selection. Our results may also provide new insight for understanding the complex genetic mechanism of fatty acid metabolism.