The susceptibility of spring soft wheat to smut of Tatarstan origin

The assessment of spring soft wheat varieties artificially infected with smut pathogen showed that more than a half of cultivars recommended to cultivation in the Republic of Tatarstan are extremely susceptible to the disease. The varieties ‘Simbirtsit’, ‘Ester’, ‘Eskada 70’, ‘Eskada 66’, ‘Eskada 109’, ‘Zlata’ and ‘Arkhat’ turned to be less susceptible to the local type of smut. During favorable for wheat infection years the most susceptible varieties of wheat grown in the ecological seed plot have the infectious degree of 1273-5821 pc. of teliospores per kernel. The amount of spores of fungi Tilletia levis during wheat growing were less than the amount of spores of fungi Tilletia caries ; the ratio of the types varied during the years, i.e. the ratio of caries to levis was 4:1 in 2012, 16:1 in 2013; 55:1 in 2014, 27:1 in 2015 and 8:1 in 2016. Some heavily infected varieties can re-infect the seeds of other varieties with the smut spores in the process of harvesting. The varieties ‘Simbirtsit’ and ‘Eskada’ (without any signs of infection), harvested by the combine machine SAMPO 2110 after the harvesting of the variety ‘Omskaya 33’ (464630 teliospores per kernel) were infected with smut spores (10295 and 1965 teliospores per kernel respectively), that was enough for mass infection of the most susceptible varieties. During the variety testing it’s necessary to conduct seed disinfection to reduce negative effect of smut on productivity if it’s impossible to renovate the variety