title: Molecular mapping of the grain iron and zinc concentration, protein content and thousand kernel weight in wheat (Triticum aestivum L.).
abstract: Genomic regions responsible for accumulation of grain iron concentration (Fe), grain zinc concentration (Zn), grain protein content (PC) and thousand kernel weight (TKW) were investigated in 286 recombinant inbred lines (RILs) derived from a cross between an old Indian wheat variety WH542 and a synthetic derivative (Triticum dicoccon PI94624/Aegilops squarrosa [409]//BCN). RILs were grown in six environments and evaluated for Fe, Zn, PC, and TKW. The population showed the continuous distribution for all the four traits, that for pooled Fe and PC was near normal, whereas, for pooled Zn, RILs exhibited positively skewed distribution. A genetic map spanning 2155.3cM was constructed using microsatellite markers covering the 21 chromosomes and used for QTL analysis. 16 quantitative trait loci (QTL) were identified in this study. Four QTLs (QGFe.iari-2A, QGFe.iari-5A, QGFe.iari-7A and QGFe.iari-7B) for Fe, five QTLs (QGZn.iari-2A, QGZn.iari-4A, QGZn.iari-5A, QGZn.iari-7A and QGZn.iari-7B) for Zn, two QTLs (QGpc.iari-2A and QGpc.iari-3A) for PC, and five QTLs (QTkw.iari-1A, QTkw.iari-2A, QTkw.iari-2B, QTkw.iari-5B and QTkw.iari-7A) for TKW were identified. The QTLs together explained 20.0%, 32.0%, 24.1% and 32.3% phenotypic variation, respectively, for Fe, Zn, PC and TKW. QGpc.iari-2A was consistently expressed in all the six environments, whereas, QGFe.iari-7B and QGZn.iari-2A were identified in two environments each apart from pooled mean. QTkw.iari-2A and QTkw.iari-7A, respectively, were identified in four and three environments apart from pooled mean. A common region in the interval of Xgwm359-Xwmc407 on chromosome 2A was associated with Fe, Zn, and PC. One more QTL for TKW was identified on chromosome 2A but in a different chromosomal region (Xgwm382-Xgwm359). Two more regions on 5A (Xgwm126-Xgwm595) and 7A (Xbarc49-Xwmc525) were found to be associated with both Fe and Zn. A QTL for TKW was identified (Xwmc525-Xbarc222) in a different chromosomal region on the same chromosome (7A). This reflects at least a partly common genetic basis for the four traits. It is concluded that fine mapping of the regions of the three chromosomes of A genome involved in determining the accumulation of Fe, Zn, PC, and TKW in this mapping population may be rewarding.
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.|Division of Crop Improvement, ICAR- Indian Institute of Wheat & Barley Research, Karnal, Haryana, India.
authors.forename: Gopalareddy
authors.initials: G
authors.lastname: Krishnappa
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Anju Mahendru
authors.identifier: http://orcid.org/0000-0001-6958-1630
authors.initials: AM
authors.lastname: Singh
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Swati
authors.initials: S
authors.lastname: Chaudhary
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Arvind Kumar
authors.initials: AK
authors.lastname: Ahlawat
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Santosh Kumar
authors.initials: SK
authors.lastname: Singh
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Ram Bihari
authors.initials: RB
authors.lastname: Shukla
authors.affiliation: Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India.
authors.forename: Jai Prakash
authors.initials: JP
authors.lastname: Jaiswal
authors.affiliation: Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Gyanendra Pratap
authors.initials: GP
authors.lastname: Singh
authors.affiliation: ICAR- Indian Agricultural Research Institute, Regional Station, Samastipur, Bihar, India.
authors.forename: Ishwar Singh
authors.initials: IS
authors.lastname: Solanki
mesh_terms: D017343:Genes, Plant; D007501:Iron / Q000032:analysis*; D010940:Plant Proteins / Q000032:analysis*; D040641:Quantitative Trait Loci; D014908:Triticum / Q000737:chemistry* / Q000235:genetics; D015032:Zinc / Q000032:analysis*
chemical_list: D010940:Plant Proteins; D007501:Iron; D015032:Zinc