回交转育结合分子标记辅助选育抗赤霉病小麦新种质OA北大核心CSTPCD

In order to determine the effects of resistance genotypes and backcross times on Fusarium head blight(Fhb)resistance and agronomic traits of progeny materials,the main resistance genes Fhb1,Fhb2 and Fhb7 were pyramided in Zhengmai 1860,which was a widely planted variety in southern Huanghuai,by backcross transformation and molecular marker-assisted selection.The Fhb resistance and main agronomic traits of different genotypes and backcross generations were analyzed.The results showed that Fhb1,Fhb2 and Fhb7 could increase the Fhb resistance by 38.9%—76.9%,and there was no significant correlation between these three resistance genes and the bad agronomic traits such as high culm,low density spikelet and low thousand-grain weight.The percentage of scabbed spikelets of BC1F2,BC2F2,BC3F2 populations in two years were 37.8%,31.4%,37.8% and 43.4%,45.8% 43.3%,respectively.Fhb resistance did not decrease with the increase of backcross times.With the increase of backcross times,the plant height of the progeny population materials decreased from 84.95 cm to 70.49 cm,the number of fruiting spikelets per panicle increased from 20.48 to 21.24,the panicle length increased from 10.23 cm to 10.49 cm,and the thousand-grain weight increased from 37.36 g to 44.80 g.The main agronomic traits of the progeny population materials after three backcrosses were similar to those of the resistance gene receptor parent variety.The new germplasms Zhengzi2021CH182-33 and Zhengzi2021CH182-41 bred in this study with excellent comprehensive agronomic properties and Fhb resistance can be further used as disease-resistance parents.