title: The wheat Phs-A1 pre-harvest sprouting resistance locus delays the rate of seed dormancy loss and maps 0.3 cM distal to the PM19 genes in UK germplasm.
abstract: The precocious germination of cereal grains before harvest, also known as pre-harvest sprouting, is an important source of yield and quality loss in cereal production. Pre-harvest sprouting is a complex grain defect and is becoming an increasing challenge due to changing climate patterns. Resistance to sprouting is multi-genic, although a significant proportion of the sprouting variation in modern wheat cultivars is controlled by a few major quantitative trait loci, including Phs-A1 in chromosome arm 4AL. Despite its importance, little is known about the physiological basis and the gene(s) underlying this important locus. In this study, we characterized Phs-A1 and show that it confers resistance to sprouting damage by affecting the rate of dormancy loss during dry seed after-ripening. We show Phs-A1 to be effective even when seeds develop at low temperature (13 °C). Comparative analysis of syntenic Phs-A1 intervals in wheat and Brachypodium uncovered ten orthologous genes, including the Plasma Membrane 19 genes (PM19-A1 and PM19-A2) previously proposed as the main candidates for this locus. However, high-resolution fine-mapping in two bi-parental UK mapping populations delimited Phs-A1 to an interval 0.3 cM distal to the PM19 genes. This study suggests the possibility that more than one causal gene underlies this major pre-harvest sprouting locus. The information and resources reported in this study will help test this hypothesis across a wider set of germplasm and will be of importance for breeding more sprouting resilient wheat varieties.
authors.affiliation: John Innes Centre, Norwich Research Park, NR4 7UH, UK.
authors.forename: Oluwaseyi
authors.initials: O
authors.lastname: Shorinola
authors.affiliation: John Innes Centre, Norwich Research Park, NR4 7UH, UK KWS UK Ltd, Hertfordshire, SG8 7RE, UK.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Bird
authors.affiliation: John Innes Centre, Norwich Research Park, NR4 7UH, UK.
authors.forename: James
authors.initials: J
authors.lastname: Simmonds
authors.affiliation: Limagrain UK Ltd, Woolpit Business Park, IP30 9UP, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Berry
authors.affiliation: Lantmannen, SE-268 81, Svalov, Sweden.
authors.forename: Tina
authors.initials: T
authors.lastname: Henriksson
authors.affiliation: RAGT Seeds, Essex, CB10 1TA, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Jack
authors.affiliation: KWS UK Ltd, Hertfordshire, SG8 7RE, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Werner
authors.affiliation: Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, LE12 5RD, UK.
authors.forename: Tanja
authors.initials: T
authors.lastname: Gerjets
authors.affiliation: Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, LE12 5RD, UK.
authors.forename: Duncan
authors.initials: D
authors.lastname: Scholefield
authors.affiliation: Institute of Experimental Botany, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 78371 Olomouc, Czech Republic.
authors.forename: Barbara
authors.initials: B
authors.lastname: Balcárková
authors.affiliation: Institute of Experimental Botany, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 78371 Olomouc, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Valárik
authors.affiliation: Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, LE12 5RD, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Holdsworth
authors.affiliation: John Innes Centre, Norwich Research Park, NR4 7UH, UK.
authors.forename: John
authors.initials: J
authors.lastname: Flintham
authors.affiliation: John Innes Centre, Norwich Research Park, NR4 7UH, UK cristobal.uauy@jic.ac.uk.
authors.forename: Cristobal
authors.identifier: 0000-0002-9814-1770
authors.initials: C
authors.lastname: Uauy
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics / Q000502:physiology; D017343:Genes, Plant / Q000235:genetics / Q000502:physiology; D060005:Genotyping Techniques; D018525:Germination / Q000235:genetics / Q000502:physiology*; D057445:Plant Dormancy / Q000235:genetics / Q000502:physiology*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D040641:Quantitative Trait Loci / Q000235:genetics* / Q000502:physiology; D014908:Triticum / Q000235:genetics / Q000254:growth & development*
keywords: After-ripening; PM19; Triticum; aestivum.; dormancy; pre-harvest sprouting; seed; synteny