Methodological peculiarities of developing infection background from broomrape seeds in sunflower breeding for immunity

The authors conducted a racial identification of seeds of broomrape Orobanche cumana Wallr., collected in 2018 at the certain sunflower fields of the Krasnodar region, the Republic of Crimea, the Saratov and Voronezh regions. The article shows that races of different virulence dominate at different fields. This requires an obligatory racial identification of the parasite seeds, which are collected at present for developing infection backgrounds during sunflower breeding for immunity to broomrape. The germination of broomrape seeds, collected at the fields where sunflower plants suffered from moisture deficiency, did not exceed 33 %. The germination test of broomrape seeds with the corresponding adjustment of the dose of infection load should be a required element of the technology of developing infection background for evaluation of resistance of sunflower breeding samples.