QTL mapping and candidate gene analysis of uppermost-internode length for new wheat germplasm'Pubing3228'
[Objective]The present study aimed to identify the new loci/genes controlling uppermost-internode length and explore the molecu-lar genetic mechanism of the uppermost-internode length in'Pubing3228'.[Method]The high density molecular linkage map was construc-ted for the RIL population derived from the cross between'Pubing3228'and'Jing4839'using 55K SNP chip.Inclusive Composite Interval Mapping method was used to carry out QTL mapping for uppermost-internode length.Based on the identified QTLs,the candidate genes were predicted for uppermost-internode length.[Result]The large variation was found for the uppermost-internode length in the RIL population and the uppermost-internode length of each line varied from 16.00 to 117.50 cm.Total of 6 QTLs were identified for uppermost-internode length and these QTLs were distributed on chromosome 2B,4B,4D,5B and 6D.LOD value of these QTLs varied from 2.55 to 7.88 and the phenotypic variation explaination(PVE)of that ranged from 3.43％to 15.84％.Furthermore,most QTLs were contributed by'Pubing3228'.Two major QTLs were identified for uppermost-internode length.One was QUIL-4B.e1 and was mapped to the distance be-tween AX-109373490 and AX-111540511 on chromosome 4B.Another was QUIL-4D.e1 and was mapped to the distance between AX-110984743 and AX-109230716 on chromosome 4D.One reliable QTL,QUIL-4D,was detected under two environments.The candidate a-nalysis was performed for uppermost-internode length and 15 candidate genes were obtained.These candidate genes mainly encoded some re-lated proteins and functional enzymes,which could regulate or affect plant metabolic activities and thus affect the uppermost-internode length of wheat.For example,TraesCS4D01 G039200 possibly encoded a fibrillar family protein that could directly affect the uppermost-internode length of wheat.TraesCS4D01 G040300 possibly encoded a metabolite transporter protein,which may affect the length uppermost-internode of wheat by regulating the distribution of metabolites in the uppermost-internode region.[Conclusion]Total of 6 QTLs and 15 candidate genes were identified for uppermost-internode length.These results not only help to elucidate the genetic mechanism of uppermost-internode length but also provide new wheat germplasm and effective information for the improvement of uppermost-internode length in the future.
NETL
NSTL
万方数据
