Genome-wide association study and transcriptome analysis reveal natural variation of key genes regulation flowering time in rapeseed

Mol Breed. 2024 May 18;44(6):40. doi: 10.1007/s11032-024-01479-4. eCollection 2024 Jun.

Abstract

Flowering time is a crucial determinant of both the yield and oil quality of rapeseed as well as a key indicator of plant maturity. We performed a genome-wide association study and transcriptome analysis to identify key genes/loci regulating flowering time in Brassica napus L. Forty-six haplotype regions harboring candidate genes were determined to be significantly associated with flowering time, and 28 of these haplotype regions overlapped with previously reported quantitative trait loci. A further investigation of these haplotype regions revealed nucleotide variations in the genes BnaFT-A02, BnaFRI-A10, and BnaFPA-A09 that correlated with phenotypic variations in flowering time. Furthermore, the co-expression network analysis indicated that BnaFT-A02 is directly linked to BnaFRI-A10 and BnaFPA-A09, in a subnetwork and also associated with 13 vernalization, 31 photoperiod, 33 autonomous pathway, and 10 gibberellin pathway genes, forming a potential network regulating flowering time in rapeseed. These results provide valuable haplotype markers for the breeding of early maturing rapeseed varieties.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-024-01479-4.

Keywords: Brassica napus; Co-expression; Flowering time; GWAS; Haplotype.