Juvenile resistance of zoned in the Russian Federation and promising triticale cultivars to leaf fungal diseases

Triticale is a grain crop developed by man as a result of crossing wheat and rye in order to combine the best traits of the parent species in a single organism. Fast introduction of triticale into practice and its wide spread cultivation is prevented by the fact that many commercial cultivars have high potential of productivity while varying in insufficient resistance to lodging and to a number of dangerous diseases. In 2023-2024 there was studied juvenile resistance to four fungal diseases (leaf rust, dark-brown leaf spot blotch, septoria blotch, powdery mildew) in 118 varieties from the register of the Russian Federation and promising triticale cultivars (winter and summer) included to the State Variety Testing over the past 5 years. The seedlings were infected with combined Puccinia triticina population, mixture of Bipolaris sorokiniana, Stagonospora nodorum and Blumeria graminis f. sp. tritici isolates collected in North-Western region of the Russian Federation. Disease resistance was evaluated according to the VIR methodology. By the results of one experiment, 93 samples of 118 were evaluated as resistant to powdery mildew. But according to the results of three independent experiments among winter and summer hexaploid triticale only 27 and 12 cultivars, respectively, were characterized by high juvenile resistance to powdery mildew. According to the results of the first experiment 10 samples were included into the class of leaf rust resistant. Only Pakhar winter cultivar was resistant to the disease according to the results of three independent experiments. All the samples of the research were highly susceptible to dark brown leaf spot blotch and septoriosis. Thus, among the triticale cultivars 39 were marked as powdery mildew resistant and 1 – as leaf rust resistant. They are of certain interest for breeding. It was also shown that for selection of reliable sources of resistance the plant material should be studied in not less than three independent experiments.