Heritable heading time variation in wheat lines with the same number of Ppd-B1 gene copies

• Published in: PloS one Vol. 12; no. 8; p. e0183745
• Main Authors: Ivaničová, Zuzana, Valárik, Miroslav, Pánková, Kateřina, Trávníčková, Martina, Doležel, Jaroslav, Šafář, Jan, Milec, Zbyněk
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 28.08.2017; Public Library of Science (PLoS)
• Subjects: Ambient temperature; B1 gene; Barley; Bioinformatics; Biology and life sciences; Bread; Chromosomes; Day length; Deoxyribonucleic acid; DNA; DNA Copy Number Variations; DNA Methylation; Environmental factors; Epigenetics; Flowering; Flowers & plants; Gene expression; Genes; Genes, Plant; Genetic Variation; Genomes; Genomics; Haplotypes; Photoperiod; Plant sciences; Promoter Regions, Genetic; Quantitative Trait Loci; Research and Analysis Methods; Seeds; Triticum - genetics; Triticum - physiology; Wheat
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0183745

The ability of plants to identify an optimal flowering time is critical for ensuring the production of viable seeds. The main environmental factors that influence the flowering time include the ambient temperature and day length. In wheat, the ability to assess the day length is controlled by photoperiod (Ppd) genes. Due to its allohexaploid nature, bread wheat carries the following three Ppd-1 genes: Ppd-A1, Ppd-B1 and Ppd-D1. While photoperiod (in)sensitivity controlled by Ppd-A1 and Ppd-D1 is mainly determined by sequence changes in the promoter region, the impact of the Ppd-B1 alleles on the heading time has been linked to changes in the copy numbers (and possibly their methylation status) and sequence changes in the promoter region. Here, we report that plants with the same number of Ppd-B1 copies may have different heading times. Differences were observed among F7 lines derived from crossing two spring hexaploid wheat varieties. Several lines carrying three copies of Ppd-B1 headed 16 days later than other plants in the population with the same number of gene copies. This effect was associated with changes in the gene expression level and methylation of the Ppd-B1 gene.