Fine mapping a domestication-related QTL for spike-related traits in a synthetic wheat.
QTL analysis using a BC5F2:3 mapping population derived from a cross between Am3, a synthetic hexaploid wheat as a donor parent, and Laizhou953, a Chinese winter wheat cultivar as a recurrent parent, showed that variation at the microsatellite locus Xgwm113 on chromosome 4B was associated with variation in grain number per spike (GN), spike length (SL), and spikelet number per spike (SPI). The Qgn.caas-4B, Qsl.caas-4B, and Qspi.caas-4B were responsible for 16.6%-35.6%, 18.0%-32.3%, and 23.7%-25.9% of the phenotypic variation present in two environments, respectively. Segregation for GN fit a Mendelian monogenic ratio. A subpopulation consisting of 497 plants was used to map the QTL to a 1.2 cM interval between Xgwm113 and Xgwm857. The three spike traits, GN, SL, and SPI, were correlated and were thus probably under the pleiotropic control of the QTL. The Am3 allele had a reduction effect on all three spike traits. Evidence for positive selective history on SSR locus Xgwm113 was supported using Ewens-Watterson's statistic test on a germplasm panel of wild and landrace entries, suggesting that this genomic region may contain genes under selection during wheat domestication.
Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
Jin
J
Wang
Xiangzheng
X
Liao
Yulian
Y
Li
Ronghua
R
Zhou
Xueju
X
Yang
Lifeng
L
Gao
Jizeng
J
Jia
D000465:Algorithms; D002874:Chromosome Mapping / Q000379:methods; D018556:Crops, Agricultural / Q000033:anatomy & histology / Q000166:cytology / Q000235:genetics; D003433:Crosses, Genetic; D004526:Efficiency; D005638:Fruit / Q000166:cytology* / Q000235:genetics; D056726:Genetic Association Studies; D018745:Genome, Plant; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000033:anatomy & histology / Q000166:cytology / Q000235:genetics*; D040641:Quantitative Trait Loci / Q000235:genetics*; D014908:Triticum / Q000033:anatomy & histology* / Q000166:cytology / Q000235:genetics*