小麦地方品种核心种质赤霉病抗性鉴定及抗性基因检测OA

Fusarium head blight(FHB)is one of the most devastating diseases affecting wheat production.Breeding disease-resistant varieties is the most economical and effective method of controlling FHB.Wheat landraces have been identified as a valuable source of germplasm for FHB resistance.In this study,we evaluated the FHB resistance of 311 core collection of wheat landraces from China's southern winter wheat region,combining the results with the previously reported major FHB resistance genes/QTL(Fhb1,Fhb2,Fhb4,Fhb5,Fhb8,Fhb9,and QFhb.yas-2DL).This allowed us to assess the effects of different resistance genes and their combinations on resistance,and to screen out excellent new sources of resistance without known genes.Among the 311 landraces,158 consistently exhibited moderate resistance or higher(50.80％)over three years,of which 65 demonstrated resistance in all three years(20.90％).The molecular marker detection results indicated that the following detection frequencies of the known resistance genes/QTL,from highest to lowest were QFhb.yas-2DL(89.39％),Fhb5(55.95％),Fhb1(47.59％),Fhb2(27.65％),Fhb4(23.15％)and Fhb8(6.75％).No varieties carrying Fhb9 were detected.Of the seven reported FHB resistance genes/QTL,varieties carrying Fhb1 exhibited the lowest average percentage of symptomatic spikelets(PSS:21.47％)and had the most significant impact on reducing PSS.The pyramiding of multiple resistance genes has the potential to enhance FHB resistance.An analysis of resistance gene combinations revealed that,among the two-gene combinations,the FHB resistance exhibited by the Fhb1+QFhb.yas-2DL combination was superior to that of the Fhb5+QFhb.yas-2DL combination.Among the three-gene combinations,the Fhb1+Fhb2+QFhb.yas-2DL combination performed better.In the four-gene combinations,the FHB resistance performance of Fhb1+Fhb4+Fhb5+QFhb.yas-2DL and Fhb1+Fhb2+Fhb5+QFhb.yas-2DL were comparable.Additionally,this study identified three promising new resistance sources of resistance:Chushanbao,Youmangyuqiumai and Caomai.These varieties did not carry any known resistance genes/QTL,exhibited moderate resistance over three consecutive years.Consequently,these varieties have the potential to be utilized in the future for the identification of novel FHB resistance genes or QTLs.