Creation and identification of compensating intercalary translocation line Dv6-IT2 carrying the powdery mildew resistance gene PmV from Dasyprum villosum
Powdery mildew is one of the main dis-eases of wheat in China.The powdery mildew resistance genes PmV and Pm21 are homologous genes from different Dasyprum villosum germplasm resources,which are used in breeding in the form of T6V#4S·6DL and T6V#2S·6AL translocation lines,respectively.Pm21 gene has been widely used in China,while PmV gene is rarely used.The main reason is that the exogenous fragment of T6V#4S·6DL translocation chromosome is too large,the transmission rate in the parent-offspring generation is low,and it is difficult to use in breeding.The creation of compensating small fragment translo-cation containing PmV is an important way to improve the transmission rate and reduce the redundancy of exogenous genes.In this study,we crossed the distal translocation line Dv6T25 carrying PmV with the proximal translocation line Dv6T36 carrying PmV.According to the principle of exogenous overlap region recombination,a compensatory intercalary transloca-tion line Dv6-IT2 carrying PmV was screened in the F2 segregating population.Marker encryption analysis was performed u-sing the reference genome sequence information of D.villosum.The results showed that the double-sided breakpoints of the translocation fragments were 35.1-36.3 Mb and 85.1-85.3 Mb,respectively,and the length of the exogenous translocation fragment was about 50 Mb.The F2 segregating population was constructed by crossing Dv6-IT2 with Yangmai 23.The mark-er results indicated that the ratio of resistance to susceptibility was consistent with the segregation ratio of 3∶1,indicating that the PmV gene could be transmitted normally in the new translocation.In this study,Dv6-IT2 was successfully created,which promoted the utilization of PmV gene in wheat powdery mildew resistance breeding.
万方数据
维普
