Powdery midlew is a dangerous disease of spring triticale in the far east

The studies were carried out in 2015–2022. in order to determine the degree of damage to collection samples of spring triticale by powdery mildew in the soil and climatic conditions of the Khabarovsk Territory of the Far East. The object of research is 84 samples of various ecological and geographical origins. The weather conditions during the research period were contrasting; with the normal precipitation for April–August being 466 mm, the excess was 16…263 mm; waterlogging contributed to an increase in relative air humidity to 100 %. The soil of the experimental plot is heavy loamy meadow-brown podzolized-gley. The distribution (R) of powdery mildew in triticale crops was high (80…100 %), the intensity of development (P) reached epiphytotic values annually. Collection varieties of spring triticale were distributed according to the intensity of disease development: moderately susceptible (13 samples), susceptible (35 samples), highly susceptible (36 samples). High correlation coefficients were calculated between the amount of precipitation in the booting-earing phase and the degree of infection of plants with powdery mildew (r = 0.861…0.897), and a linear regression equation was compiled that shows the dependence of the intensity of development of the powdery mildew pathogen and the amount of precipitation in the second ten days of June. Thus, spring triticale varieties were identified that have average susceptibility to powdery mildew pathogens (P = 30…40 %): Amore, Saur, Prag 409, Dagvo (Russia), Lana, Lotos (Belarus), Zgurivskiy, Oberig Kharkovskiy (Ukraine), 70 HN 458 (Canada), Je 57 (USA), Anoas 5, MX 51 (Mexico), Tleridal (Switzerland).