title: Validation of a 1DL earlinessper se(eps) flowering QTL in bread wheat (Triticum aestivum).
abstract: Vernalization, photoperiod and the relatively poorly defined earlinessper se(eps) genes regulate flowering in plants. We report here the validation of a majorepsquantitative trait locus (QTL) located on wheat 1DL using near isogenic lines (NILs). We used four independent pairs of NILs derived from a cross between Spark and Rialto winter wheat varieties, grown in both the field and controlled environments. NILs carrying the Spark allele, defined by QTL flanking markersXgdm111andXbarc62, consistently flowered 3-5 days earlier when fully vernalized relative to those with the Rialto. The effect was independent of photoperiod under field conditions, short days (10-h light), long days (16-h light) and very long days (20-h light). These results validate our original QTL identified using doubled haploid (DH) populations. This QTL represents variation maintained in elite north-western European winter wheat germplasm. The two DH lines used to develop the NILs, SR9 and SR23 enabled us to define the location of the 1DL QTL downstream of markerXgdm111. SR9 has the Spark 1DL arm while SR23 has a recombinant 1DL arm with the Spark allele fromXgdm111to the distal end. Our work suggests that marker assisted selection ofepseffects is feasible and useful even before the genes are cloned. This meansepsgenes can be defined and positionally cloned in the same way as the photoperiod and vernalization genes have been. This validation study is a first step towards fine mapping and eventually cloning the gene directly in hexaploid wheat.
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Meluleki
authors.initials: M
authors.lastname: Zikhali
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Michelle
authors.initials: M
authors.lastname: Leverington-Waite
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Lesley
authors.initials: L
authors.lastname: Fish
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: James
authors.initials: J
authors.lastname: Simmonds
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Orford
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Luzie U
authors.initials: LU
authors.lastname: Wingen
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Goram
authors.affiliation: The John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Gosman
authors.affiliation: The John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE UK.
authors.forename: Alison
authors.initials: A
authors.lastname: Bentley
authors.affiliation: John Innes Centre, Norwich Research Park, Norwich, Norfolk, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Griffiths
keywords: Earliness per se (eps); Near isogenic lines (NILs); Photoperiod; Vernalization; Wheat