New Fusarium head blight-resistant sources from Asian wheat germplasm

Fusarium head blight (FHB) is an important disease of wheat worldwide. Severe infection can dramatically reduce grain yield and quality. Resistant cultivars have been identified from several countries. However, only a few sources of FHB resistance showed stable FHB resistance across environments and have been used as the major source of resistance in breeding programs. To diversify the wheat FHB-resistance gene pool, new sources of FHB-resistance are desired. Ninety-four selected wheat landraces and cultivars, mainly from China and Japan, have been evaluated for FHB severity and deoxynivalenol (DON) content. Low DON content was correlated with resistance to the FHB symptom spread within an infected spike, but not with the resistance to FHB initial infection. Two-thirds of the accessions were either resistant or moderately resistant to FHB. Among them, 26 highly resistant accessions mainly originated from China and Japan. Fifteen of them had less than 2 mg kg(-1) DON in harvested grain, six of which showed all three types of resistance. Most of these resistant accessions lack known pedigree relations to Sumai 3, suggesting that some of them may carry genes for resistance to FHB and DON accumulation different from those in Sumai 3.