Genotypic and physiological adaptation to fungi diseases of barley cultivars bred in Farc of the north-east

The FGBNU FARC of the North-East in 2019-2021 conducted an immunological assessment and analysis of the effect of fungal diseases on the photosynthetic complex and infection of seeds in 16 barley varieties created over the past 30 years to substantiate the genotypic and physiological adaptation of plants to mycosis. The study was carried out on a phytopathological site with artificial inoculation with Helminthosporium spp. and evaluated for resistance to root rot, net and dark brown spots using wellknown methods. Varieties Dina, Forward, Dobryak and new lines 288-12, 52-12 and 94-13 are characterized by high and moderate resistance to diseases. A trend has been found to reduce root rot and dark brown spotting in barley lines, but there is no progress in breeding with respect to net spotting. Eight microbial taxa were identified in the structure of seed microflora. The species Bipolaris sorokiniana was identified in all seed samples, with the exception of the Dina variety, with a share in the contaminant from 8.2 % (Andrei) to 71.0 % (Pamyat Rodina) and an average of 41.1 % for the assortment; species of Alternaria spp. and Bacillus spp. - in 14 seed samples with an average share of 30.8 and 8.0 %; Fusarium spp. in 13 varieties with an average share of 6.8 %. A weak relationship (r) between seed infection and the development of root rot (r=0.24), dark brown and net spot (r=0.25 and r=0.16) was revealed; medium and significant relationship (at P ≥ 095) - between the development of root rot and dark brown leaf spot (r= 0.56). The negative effect of dark brown spotting was manifested in a decrease in the content of Chl a (r=-0.134) and Car (r=-0.217); net spotting - in a decrease in SSC (r=-0.439); root rot - in the reduction of Chl a (r=-0.325), Chl b (r=-0.316) and Car (r=-0.371).