Blend wheat AL-type hybrid and using SSRs to determine the purity of hybrid seeds

Heterosis is a promising approach to increase wheat yield from a limited planting area. In this study, a fine quality restorer line 99AR144-1 and three stable male sterile lines, AL18A, AL36A and AL20A, were assigned as male and female, respectively. Seeds of the wheat line 99AR144-1 and three male sterile lines were mixed according to different proportions and then planted at an experimental farm at the Xinjiang Academy of Agri-Reclamation Sciences from 2013 to 2016. When the mixed sowing ratios of combinations 2 (AL36A × 99AR144-1) and 3 (AL20A × 99AR144-1) were 6 to 8%, the seed production yields were higher than the control; the yield of hybrid seed production increased by 98.8 and 19.9%, respectively. This increase was attributed to a rise in the outcrossing seed setting rate. Further, this study used the Xbarc-8 SSR (simple sequence repeat) molecular marker to identify the purity of blend hybrid seeds and establish a regression equation for hybrid seed purity testing. The coefficient of the regression equation were 0.9878 and 0.9689 respectively, which shows that the purity of hybrids can be accurately predicted by using this equation. This method can quickly and accurately identify the seed purity in mixed seed production.