The Identification Of Resistance To FHB And Polymorphism Of Resistant Genes In Barley

Fusarium head blight (FHB) is a widespread disease of barley. The risk of FHBinfection is high when warm and humid weather occurs around flowering. In NorthAmerica and China, heavy epidemics mainly caused by Fusarium graminearumSchwabe. Apart from direct yield losses, the most serious concern is the contaminationof the crop with mycotoxins. Barley lots contaminated with deoxynivalenol (DON) maybe rejected by the malting and brewing industry.In 2005 and 2006, the resistance to spread and invasion of Fusarium head blight wasevaluated for 262 Barley cultivars coming from China, America, Canada, Japan usingsingle floret injection and spay inoculation. The result showed there is the resistance tospread as well as to initial infection of Fusarium head blight in barley. After comparingthe proportion of scabbed spikelets on 21 days after inoculation,9 varieties were identifiedas resistant, they are Yan 96157,2000 Pin 12,Xiu 9744,Vivar,Phoenix,Yan 94148,Jian 35,Yan 97001 and 96AC20-30, which occupying 3.44% of the total tested cultivars. Thecomparison of different indexes such as proportion of scabbed spikelets, rate of diseasedheads, diseased index, infection rating on 21 days after spay inoculation suggested thatthree resistance types exited. The genetic diversity among eighty-seven barley cultivars was investigated using aset of 54 SSR primers related and not related to barley FHB QTL. The barley SSRprimers located in 2H, 6H chromosomes. QTL were also used to investigate the geneticdiversity of 34 resistance and sensitive cultivars in comparison with Ciho4196, Chevron,Frederickson, Stander, Gobernadora. On the 54 SSR loci,a total of 193 alleles had beendetected in these elite cultivars. At each SSR locus, 1 to 11 alleles could be detected withan average of 3.57.Based on SSR data, cluster analysis among the 87 cultivars showedthat all the cultivars were clustered into two groups, cultivars come from the same areawere also clustered into the same group. The first group includes two cultivars that comefrom China, Japan and Europe, North America separately. The second group barleycultivars mainly come from Yancheng and North America area. Result gained from geneanalysis is the same with resistance evaluation. Haplotype analysis show that resistantcultivars 96AC20-30, Xiu 9744, Yan 94148, Yan 97001 have the same sites withFrederickson on least 3 SSR markers of chromosome 2 H, but Phoenix, Vivar, Jian 35show different sites, so then may have the different resistant genes.