QTL Mapping For Gluten Strength And Steamed Bread In Common Wheat (Triticum Aestivum L.)

Wheat（Triticum aestivum L.）as an important food crop,its quality is of great importance to improve people’s lives.Wheat nutritional quality including amino acid balance and protein content,and processing quality is divided into milling quality and food processing quality.As a staple food in northern China,steamed bread quality directly affects the level of people’s lives.Gluten strength is one of the important indexes of food processing quality and has important significance for wheat quality improvement.In the present study,linkage analysis and association analysis based on high density genetic map for gluten strength,17 kinds of amino acid content and the processing quality of steamed bread were studied using a recombinant inbred line（RIL）consisting of 173 lines derived from a“Shannong01-35 × Gaocheng9411”cross and a natural population consisting of 205 wheat varieties.And the main QTLs,QSed1 B.1-26 and QHei5 B.5-488 for sedimentation value and the height of the steamed bread were developed into practical CAPS markers.In addition,a new CAPS marker was developed in QHei5 B.5-488 target segment using bioinformatics methods,which could be used for fine mapping.The mainly results of the study were as follows:1 Important genetic loci: the QTLs for gluten strength were detected on chromosomes 1A,1B,1D,4B,7B and 7D.Among them,QSed1 B.1-26,QSed1D-4,QGI1D-2 and QDG4 B.4-13 were the main QTLs affected gluten strength,with contribution over 10%.The QTLs for amino acids were detected on chromosomes 1A,1B,2A,2B,3A,3B,4A,4B,5B,6B and 7A.Among them,1B.4-38（TA004690-1102-RAC875_REP_C113316₃05）and the SNP marher BS00065510₅1 on chromosome 1D controlled a variety of amino acids.The QTLs for the processing quality of steamed bread were detected on chromosomes 1A,1B,2A,3A,3B,4A,5B and 7B.Among them,QHei5 B.5-488 and 1D-116（wsnp_Ex_c35886₄3949442,wsnp_Ex_c35886₄3950574,BS00093390₅1）were main major loci.2 Practical CAPS marker development: according to the sequence information of SNP marker TDURUM_CONTIG98378₄52 and KU_C14332₂2613741,1B-CAPS1 and 5B-CAPS2 linked to wheat sedimentation value and the height of steamed were developed,which can be applied in marker-assisted selection.3 QHei5 B.5-488 region genetic map density: a new molecular markers CAPS-5B-488 was developed,and the genetic distance from RAC875_C29431₁849 to CAPS-5B-488 was 3.51 cM,from WSNP_KU_C14332₂2613741 was 1.65 cM.In addition,the final QTL analysis showed that the gene distance controlling the height of steamed bread reduced to 3.51 cM.