Molecular Cytogenetic Characterization and Fusarium Head Blight of Five Wheat Thinopyrum Intermedium Partial Amphiploids

Background: Partial amphiploids created by crossing octoploid tritelytrigia and Thinopyrum intermedium are important intermediates in wheat breeding because of their resistance to major wheat diseases. We examined the chromosome compositions of five wheat Th. intermedium partial amphiploids using GISH and multicolor FISH. Results: The result revealed that five lines had 10 14 J genome chromosomes from Th. intermedium and 42 common wheat chromosomes, using the J genomic DNA from Th. bessarabicum and the oligo probes pAs1 1 , pAs1 3 , AFA 4 , GAA ) 10, and pSc119.2 1 . Five lines resembled the parent Ganmai 8 but had better protein contents. P rotein contents of t wo lines HS2 2 and HS2 5 were up to more than 20%. Evaluation of Fusarium head blight (FHB) resistance revealed that the percent of symptomatic spikelets (PSS) of these lines were below 30%. Lines HS2 2, HS2 4, HS2 5, and HS2 16 were less than 20%. Line HS2 5 with 14 J genome chromosomes from Th. intermedium showed the best disease resistance, with PSS values of 10.8% and 16.6% in 2016 and 2017, respectively. Conclusions: New wheat Th. intermedium amphiploids with the J genome chromosomes were identified and can be considered as a valuable source of FHB resistance in wheat breeding.