Identification of Markers Linked to Flower Initiation Genes in the Hexaploid Oat Avena sativa

Flowering time is a decisive factor in the adaptation of oat, and its transition from vegetative to reproductive phase is mainly regulated by photoperiod and vernalization. The objective of this study was to identify molecular markers linked to flower initiation genes in the hexaploid oat Avena sativa.

A genetic population of 154 recombinant inbred lines (RILs) was analyzed in this study. Parental lines and RILs were evaluated for heading date in field tests in the Southern Brazil for the growing seasons of 2008, 2009, and 2012. DArT, AFLP, and SSR markers were tested for the QTL analyses.

Three regions of the map contained QTL affecting flowering time in the Brazilian ‘UFRGS 8 x UFRGS 930605’ mapping population. Phenotypic variation observed for the number of days to flowering was associated with the AFLP marker U86PM2 (linkage group unknown), with DArT markers on linkage group 1, and with DArT and SSR markers on linkage group 6. The locus U86M2 showed the largest effects in all growing seasons and in combination of years. These QTLs support the hypothesis that alleles with different effects for flower initiation are present in the oat mapping population.

Although there is still considerable research needed to validate these QTLs and to develop simple PCR-based markers to assist in the selection of germplasm with specific adaptations to flowering time, the results from the current study contribute to a better understanding of genetic and molecular factors affecting flowering time in oat.