Some Biological Characteristics of the Phytopthora Infestans Fungus Provoking Phytophtorosis Disease in Potatoes

In the article, the most damaging phytophthorosis disease of potatoes in Uzbekistan is mentioned and information about the spread of P. infestans fungi, the source of infection conservation and harm of disease-causing P. infestans is given. Including fungus best growth and development of fungi P. infestans at a temperature of 20–22 °C in oat Agar and potato—glucose-agaric nutrient media was determined, in which the Daily growth rate reached 30–31 mm. The rate of growth is slightly less than in potato agarics, and its growth in one day was 29–30 mm. The growth and development of the fungus at temperatures of 14–15 °C and 32 °C was slow. Potatoes are separated from different varieties fungus P. infestans the phytocyclic properties of P. infestans Lily strains were studied, it was found that of the strains 33 separated from the “Akrab” variety, 4 isolated from the “Rozara” variety, 11 isolated from the “Sante” variety and 48 isolated from the “Latona” variety were the most active. Potatoes are separated from different varieties When the pathogenic properties of P. infestans Lily strains were studied, strains 4, 33, and 45, separated from the varieties “Rozara”, “Akrab” and “Romano”, which were planted earlier in local conditions, strongly damaged these types of crops, that is, this indicator is in the “Rozara” variety, respectively 64.7%, 62.3%, 54.2%. In the “Akrab” variety, it was equal to 60.1%, 66.8%, 52.1%, and in the “Romano” variety-53.8%, 54.7%, and 59.6%.