The article highlights the results of studying hybrid combinations of common onion to the Botrytis allii Munn pathogen. It is found out that as for the combinations being studied the resistance to pathogen was inherited as dominant, intermediate or recessive trait. Better resistance to neck rot was inherent in the hybrid combinations which parents comprised resistant and immune varieties, insofar as the determination of inheritance coefficient has indicated F1 hybrids have this characteristic expression dependant by 50 to 78% on the parental plant (h2 =0,50–0,78). Studying the determination of the impact of both parental components on inheritance of the resistance to B. allii pathogen showed that the regression coefficient subject to hybrid combination fell within R = 0,12–0,39, while the resistance coefficient within 0,24–0,78, respectively. Efficiency of selection is proved by the trait of resistance to neck rot based on the populations of Grandina х Mavka, Olina х Grandina, Grandina х Skvyrska і Skvyrska х Grandina, as their respective inheritance coefficient reached the level of 0,42 to 0,78.

Race-specific resistance of 19 common millet varieties that are firstly listed on the State Register of Plant Varieties Suitable for Dissemination in Ukraine in 2013 is assessed. It is found that almost half of the varieties are infected with all smut races, part of them is resistant only to the first group of smut races, and there is no variety to be resistant to all races of this disease. It is concluded that common millet varieties are needed to be examined for resistance to smut races

The article highlights the results of studying hybrid combinations of common onion to the Botrytis allii Munn pathogen. It is found out that as for the combinations being studied the resistance to pathogen was inherited as dominant, intermediate or recessive trait. Better resistance to neck rot was inherent in the hybrid combinations which parents comprised resistant and immune varieties, insofar as the determination of inheritance coefficient has indicated F1 hybrids have this characteristic expression dependant by 50 to 78% on the parental plant (h2 =0,50–0,78). Studying the determination of the impact of both parental components on inheritance of the resistance to B. allii pathogen showed that the regression coefficient subject to hybrid combination fell within R = 0,12–0,39, while the resistance coefficient within 0,24–0,78, respectively. Efficiency of selection is proved by the trait of resistance to neck rot based on the populations of Grandina х Mavka, Olina х Grandina, Grandina х Skvyrska і Skvyrska х Grandina, as their respective inheritance coefficient reached the level of 0,42 to 0,78.

Race-specific resistance of 19 common millet varieties that are firstly listed on the State Register of Plant Varieties Suitable for Dissemination in Ukraine in 2013 is assessed. It is found that almost half of the varieties are infected with all smut races, part of them is resistant only to the first group of smut races, and there is no variety to be resistant to all races of this disease. It is concluded that common millet varieties are needed to be examined for resistance to smut races

Collection samples of the onion of varying ecological and geographical origin have been scrutinized under the conditions of Chernigiv region to establish their susceptibility to Botrytis allii Munn pathogen. It is noted that the disease develops, first of all, on samples with dry leafs colored white, and established that enhanced resistance to the pathogen is inherent in forms of anthocyanin or red coloration or dry and damp skins (Rubin, Amfora, Veselka, Mavka, Braushverska Chervona, Venta F1, Tango F1, Golubka). Sources of resistance to neck rot are indicated (Olina, Texas Curli, Violetta, Red Baron F1), which have not been damaged by the pathogen at all through the three years of study. The use of parental pars quality of such samples will enable to produce prospective breeding material at hybridization.