Inheritance And Mapping Of Gene Controlling Supernumerary Spikelet In Tetraploid Branched Spike Wheat "Jiutoumai"

As one of the most important grain crops, the substantial increase of wheat (Triticum aestivum L.) production has become more important for worldwide food safety. Previous studies have showed the spike architecture is closely related with the wheat production. The supernumerary spikelet, a variation in wheat spikes, could significantly increase the spikelet number, even the mature grain number. Therefore, studying the genetic mechanism responsible for the spike architecture will be the future direction for wheat breeding.Two RIL populations derived from the cross between tetraploid wheat line "jiutoumai" and Khapli were used to analyze the inheritance of supernumerary spikelet. According to our investigation, three spike types were observed in populations:normal spike, branched spike and the lateral supernumerary spikelet type. Among which, branched spike and the lateral supernumerary spikelet type were classified as supernumerary spikelet type. Genetic analysis showed the separation ratio of branched spikes and no branched spikes in two populations both were1:3, which showed two genes determined the branched spike character. However, the separation ratio of lateral supernumerary spikelet type and normal spike in two populations both were1:1, which showed lateral supernumerary spikelet character in "jiutoumai" was controlled by a single gene.To map the gene controlling lateral supernumerary spikelet character, bulk analysis was conducted. The result showed that the gene was linked with SSR molecular markers Xwmc453、Xgwm122、Xwmc296、Xgwm275、Xgwm339、Xgwm515、Xgwm95、 Xgwm249and Xgwm558on the short arm of chromosome2A, was temperately named lssl. In addition, two STS markers Xmag2090and Xmag3635were mapped close to lssl with genetic distance both of2.4cM.