title: Allele frequencies in theVRN-A1,VRN-B1andVRN-D1vernalization response andPPD-B1andPPD-D1photoperiod sensitivity genes, and their effects on heading in a diverse set of wheat cultivars (Triticum aestivumL.).
abstract: Heading of cereals is determined by complex genetic and environmental factors in which genes responsible for vernalization and photoperiod sensitivity play a decisive role. Our aim was to use diagnostic molecular markers to determine the main allele types inVRN-A1,VRN-B1,VRN-D1,PPD-B1andPPD-D1in a worldwide wheat collection of 683 genotypes and to investigate the effect of these alleles on heading in the field. The dominantVRN-A1,VRN-B1andVRN-D1alleles were present at a low frequency. ThePPD-D1aphotoperiod-insensitive allele was carried by 57 % of the cultivars and was most frequent in Asian and European cultivars. ThePPD-B1photoperiod-insensitive allele was carried by 22 % of the genotypes from Asia, America and Europe. Nine versions of thePPD-B1-insensitive allele were identified based on gene copy number and intercopy structure. The allele compositions inPPD-D1,PPD-B1andVRN-D1significantly influenced heading and together explained 37.5 % of the phenotypic variance. The role of gene model increased to 39.1 % whenPPD-B1intercopy structure was taken into account instead of overallPPD-B1type (sensitive vs. insensitive). As a single component,PPD-D1had the most important role (28.0 % of the phenotypic variance), followed byPPD-B1(12.3 % forPPD-B1_overall, and 15.1 % forPPD-B1_intercopy) andVRN-D1(2.2 %). Significant gene interactions were identified between the marker alleles withinPPD-B1and betweenVRN-D1and the twoPPD1genes. The earliest heading genotypes were those with the photoperiod-insensitive allele inPPD-D1andPPD-B1, and with the spring allele forVRN-D1and the winter alleles forVRN-A1andVRN-B1. This combination could only be detected in genotypes from Southern Europe and Asia. Late-heading genotypes had the sensitivity alleles for bothPPD1genes, regardless of the allelic composition of theVRN1genes. There was a 10-day difference in heading between the earliest and latest groups under field conditions.
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: Tibor
authors: T
authors: Kiss
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: Krisztina
authors: K
authors: Balla
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: Ottó
authors: O
authors: Veisz
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: László
authors: L
authors: Láng
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: Zoltán
authors: Z
authors: Bedő
authors: John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK.
authors: Simon
authors: S
authors: Griffiths
authors: IDna Genetics Ltd, Norwich Research Park, Norwich, NR4 7UH UK.
authors: Peter
authors: P
authors: Isaac
authors: Centre for Agricultural Research, Agricultural Institute, Hungarian Academy of Sciences, Martonvásár, 2462 Hungary.
authors: Ildikó
authors: I
authors: Karsai
keywords: DEV49–DEV59 plant development phases; Photoperiod response; Vernalization genes; Wheat (T. aestivum L.)