Holiachuk Y. Late blight of a potato and immunological method of protection in the conditions of the western Forest-steppe of Ukraine

Thesis is devoted to specification of biological features of the causal organism of a late blight of potato - Рh. infestans and to revealing of sources of resistance to pathogen among the widespread and perspective varieties and potato hybrids. As a result of researches spreading, dynamics of development and degree of harmfulness of the causal organism of a late blight of potato in the conditions of the western Forest-steppe of Ukraine are established. The races structure of the causal organism is defined. For the first time the sexual process of pathogen in laboratory conditions is fixed. Ability of oospores to tolerate unfavorable conditions of the winter season in field conditions and to cause a lesion of plants of a potato in a following growing season is proved. Presence at populations of Рh. infestans isolations, belonging to mycelium of different mating type is established. The allocation procedure isolations of the causal organism of a late blight of potato in pure culture is modified. The resistance of an above-ground part of plants and tubers of varieties and potato hybrids to a lesion of pathogen in field and laboratory conditions is investigated.