Biomics

In the last decade, works have appeared that propose the use of wheat susceptibility genes to the pathogen Stagonospora nodorum Berk. (Snn) as molecular markers for marker-based selection. Relationships in the pathosystem "wheat - S. nodorum" are carried out according to the "gene-forgene" type in mirror image, i.e. the interaction of necrotrophic effectors of the fungus SnTox with the products of host susceptibility genes Snn leads to the development of the disease. The work studied the interactions of SnToxA-Tsn1 and SnTox1-Snn1, which play an important role in the development of Septoria nodorum blotch in soft and hard wheats. Using gene-specific primers for the Tsn1 and Snn1 susceptibility genes, PCR diagnostics of samples of polyploid wheat species of the genus Triticum and ancient varieties of T. aestivum from the PGR VIR collection for resistance to Stagonospora nodorum was carried out. Both dominant alleles of the Tsn1 and Snn1 genes were found in the tetraploid wheat T. durum x-46 and two ancient spring cultivars Selkirk and Salamouni. The dominant allele of the Snn1 gene was found in four studied ancient varieties of common wheat of winter and spring types of development. Primary screening of 12 accessions from the PGR VIR collection revealed two resistant accessions among tetraploid wheat species T. militinae k-59942 and T. timopheevii k-58666 and three resistant varieties of hexaploid wheat T. aestivum with winter development type Mironovskaya 808, Amelio and Susquehanna. These accessions are a promising source for gene introgression into cultivated wheats and material for breeding new wheat varieties.

Stagonospora nodorum Berk.; Triticum L.; necrotrophic effectors SnToxA and SnTox1; susceptibility genes Tsn1 иSnn1; selection

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