Journal article

Publication year: 2021

Pages: 1217-1231

Journal: Theoretical and Applied Genetics

Volume number: 134

Issue number: 4

ISSN: 0040-5752

eISSN: 1432-2242

Open access status: Hybrid

DOI Link: https://doi.org/10.1007/s00122-021-03768-4

Publisher: Springer

Abstract: 
Perfect timing of flowering is crucial for optimal pollination and high seed yield. Extensive previous studies of flowering behavior in Brassica napus (canola, rapeseed) identified mutations in key flowering regulators which differentiate winter, semi-winter and spring ecotypes. However, because these are generally fixed in locally adapted genotypes, they have only limited relevance for fine adjustment of flowering time in elite cultivar gene pools. In crosses between ecotypes, the ecotype-specific major-effect mutations mask minor-effect loci of interest for breeding. Here, we investigated flowering time in a multiparental mapping population derived from seven elite winter oilseed rape cultivars which are fixed for major-effect mutations separating winter-type rapeseed from other ecotypes. Association mapping revealed eight genomic regions on chromosomes A02, C02 and C03 associating with fine modulation of flowering time. Long-read genomic resequencing of the seven parental lines identified seven structural variants coinciding with candidate genes for flowering time within chromosome regions associated with flowering time. Segregation patterns for these variants in the elite multiparental population and a diversity set of winter types using locus-specific assays revealed significant associations with flowering time for three deletions on chromosome A02. One of these was a previously undescribed 288 bp deletion within the second intron of FLOWERING LOCUS T on chromosome A02, emphasizing the advantage of long-read sequencing for detection of structural variants in this size range. Detailed analysis revealed the impact of this specific deletion on flowering-time modulation under extreme environments and varying day lengths in elite, winter-type oilseed rape.

Harvard Citation style: Vollrath, P., Chawla, H., Schiessl, S., Gabur, I., Lee, H., Snowdon, R., et al. (2021) A novel deletion in FLOWERING LOCUS T modulates flowering time in winter oilseed rape, TAG Theoretical and Applied Genetics, 134(4), pp. 1217-1231. https://doi.org/10.1007/s00122-021-03768-4

APA Citation style: Vollrath, P., Chawla, H., Schiessl, S., Gabur, I., Lee, H., Snowdon, R., & Obermeier, C. (2021). A novel deletion in FLOWERING LOCUS T modulates flowering time in winter oilseed rape. TAG Theoretical and Applied Genetics. 134(4), 1217-1231. https://doi.org/10.1007/s00122-021-03768-4