Discovery And Mapping Of Qinhei No.1 Wheat Dwarf Gene

Since the 1960 s,in the wheat breeding and production,the application of the dwarf gene Rht1 and Rht2 were derived from “Nonglin 10” effectively solved the problem of wheat lodging and significantly increased production.Therefore,the dwarf gene plays a crucial role in reducing plant height,improving the lodging resistance and yield of wheat.In order to discover the new dwarf genes,in this study,the 660 kSNP chip pool was tested on the tetraploid dwarf wheat Qinhei 1 and its F2 population.The new dwarf gene Rht-QH was discovered,located,and investigated to measure the impact on some agronomic traits.The key findings are mentioned as follows:1.The "Qinhei No.1"(QH-1)was sensitive to gibberellin by gibberellin sensitivity test,while the control material dwarf durum wheat(DW,containing Rht1)was not sensitive to gibberellin.The reasons are that both are tetraploid dwarf materials,it is speculated that the dwarf gene in durum wheat is different from the dwarf gene in "Qinhei 1".2.F2 segregating populations were generated by hybridization of QH-1 and DW.Detecting the allelicity of the dwarf gene in both materials,it was found that the plant height of the population plants was clearly separated,indicating that the two dwarf genes are non-alleles.Using the extreme individual pool to do 660 KSNP chip pooling detection,the two dwarf loci were detected on chromosomes 4B and 2A,respectively.Molecular marker detection showed that DW contains Rht1,and QH-1 might contain a new dwarf gene that could tentatively be named as Rht-QH.3.Genetic analysis of plant height traits in offspring segregated populations were containing only new dwarf genes and the finding was that the plant height separation ratio conformed to the dwarf : high stalk = 3:1,meaning that the new dwarf gene is dominant single gene inheritance in the separation group.4.Gene mapping with newly developed KSAP markers,positioning the dwarf gene Rht-QH into the KASP marker 2A1.7-2A2.3 region on 2A,and the physical distance between 2A1.7-2A2.3 is 17.74 Mb.5.To investigate the effect of Rht-QH gene on some agronomic traits.The Rht-QH gene was found to reduce the height of the plant by 26.6%,this gene significantly increased the number of spikelets in the main stem and also increased the 1000-grain weight.