title: Genetic dissection of grain size and grain number trade-offs in CIMMYT wheat germplasm.
abstract: Grain weight (GW) and number per unit area of land (GN) are the primary components of grain yield in wheat. In segregating populations both yield components often show a negative correlation among themselves. Here we use a recombinant doubled haploid population of 105 individuals developed from the CIMMYT varieties Weebill and Bacanora to understand the relative contribution of these components to grain yield and their interaction with each other. Weebill was chosen for its high GW and Bacanora for high GN. The population was phenotyped in Mexico, Argentina, Chile and the UK. Two loci influencing grain yield were indicated on 1B and 7B after QTL analysis. Weebill contributed the increasing alleles. The 1B effect, which is probably caused by to the 1BL.1RS rye introgression in Bacanora, was a result of increased GN, whereas, the 7B QTL controls GW. We concluded that increased in GW from Weebill 7B allele is not accompanied by a significant reduction in grain number. The extent of the GW and GN trade-off is reduced. This makes this locus an attractive target for marker assisted selection to develop high yielding bold grain varieties like Weebill. AMMI analysis was used to show that the 7B Weebill allele appears to contribute to yield stability.
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Griffiths
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: Luzie
authors.initials: L
authors.lastname: Wingen
authors.affiliation: CIMMYT, Int. Apdo. Postal 6-641, 06600 México, DF, Mexico.
authors.forename: Julian
authors.initials: J
authors.lastname: Pietragalla
authors.affiliation: Cátedra de Cerealicultura, Departamento de Producción Vegetal, and IFEVA-CONICET, Facultad de Agronomía, Universidad de Buenos Aires, Av. San Martin 4453, C1417DSE Buenos Aires, Argentina.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Garcia
authors.affiliation: Plant Production and Plant Protection Institute, Universidad Austral de Chile, Campus Isla Teja, Valdivia, Chile.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Hasan
authors.affiliation: Cátedra de Cerealicultura, Departamento de Producción Vegetal, and IFEVA-CONICET, Facultad de Agronomía, Universidad de Buenos Aires, Av. San Martin 4453, C1417DSE Buenos Aires, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Miralles
authors.affiliation: Plant Production and Plant Protection Institute, Universidad Austral de Chile, Campus Isla Teja, Valdivia, Chile.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Calderini
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: Jignaben Bipinchandra
authors.initials: JB
authors.lastname: Ankleshwaria
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: Michelle Leverington
authors.initials: ML
authors.lastname: Waite
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: James
authors.initials: J
authors.lastname: Simmonds
authors.affiliation: John Innes Centre, Norwich research Park, Norwich, NR4 7UH, Norfolk, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Snape
authors.affiliation: CIMMYT, Int. Apdo. Postal 6-641, 06600 México, DF, Mexico.
authors.forename: Matthew
authors.initials: M
authors.lastname: Reynolds
mesh_terms: D002523:Edible Grain / Q000033:anatomy & histology* / Q000235:genetics* / Q000600:supply & distribution; D017343:Genes, Plant; D056726:Genetic Association Studies; D000069600:Plant Breeding; D040641:Quantitative Trait Loci; D014908:Triticum / Q000033:anatomy & histology* / Q000235:genetics* / Q000254:growth & development