title: Genetic control of grain yield and grain physical characteristics in a bread wheat population grown under a range of environmental conditions.
abstract: Genetic analysis of the yield and physical quality of wheat revealed complex genetic control, including strong effects of photoperiod-sensitivity loci. Environmental conditions such as moisture deficit and high temperatures during the growing period affect the grain yield and grain characteristics of bread wheat (Triticum aestivum L.). The aim of this study was to map quantitative trait loci (QTL) for grain yield and grain quality traits using a Drysdale/Gladius bread wheat mapping population grown under a range of environmental conditions in Australia and Mexico. In general, yield and grain quality were reduced in environments exposed to drought and/or heat stress. Despite large effects of known photoperiod-sensitivity loci (Ppd-B1 and Ppd-D1) on crop development, grain yield and grain quality traits, it was possible to detect QTL elsewhere in the genome. Some of these QTL were detected consistently across environments. A locus on chromosome 6A (TaGW2) that is known to be associated with grain development was associated with grain width, thickness and roundness. The grain hardness (Ha) locus on chromosome 5D was associated with particle size index and flour extraction and a region on chromosome 3B was associated with grain width, thickness, thousand grain weight and yield. The genetic control of grain length appeared to be largely independent of the genetic control of the other grain dimensions. As expected, effects on grain yield were detected at loci that also affected yield components. Some QTL displayed QTL-by-environment interactions, with some having effects only in environments subject to water limitation and/or heat stress.
authors.affiliation: Australian Centre for Plant Functional Genomics and School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia.
authors.forename: Lancelot
authors.initials: L
authors.lastname: Maphosa
authors.forename: Peter
authors.initials: P
authors.lastname: Langridge
authors.forename: Helen
authors.initials: H
authors.lastname: Taylor
authors.forename: Boris
authors.initials: B
authors.lastname: Parent
authors.forename: Livinus C
authors.initials: LC
authors.lastname: Emebiri
authors.forename: Haydn
authors.initials: H
authors.lastname: Kuchel
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Reynolds
authors.forename: Ken J
authors.initials: KJ
authors.lastname: Chalmers
authors.forename: Anzu
authors.initials: A
authors.lastname: Okada
authors.forename: James
authors.initials: J
authors.lastname: Edwards
authors.forename: Diane E
authors.initials: DE
authors.lastname: Mather
mesh_terms: D001315:Australia; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D055864:Droughts; D059647:Gene-Environment Interaction; D008040:Genetic Linkage; D005838:Genotype; D006358:Hot Temperature; D018895:Microsatellite Repeats; D010316:Particle Size; D010641:Phenotype; D040641:Quantitative Trait Loci; D012639:Seeds / Q000235:genetics / Q000254:growth & development*; D013312:Stress, Physiological; D014908:Triticum / Q000235:genetics*
chemical_list: D018744:DNA, Plant