Tymoschuk O. Winter Rot of Potato and The Measures on Limitation of its Development Under The Conditions of Polyssya of Ukraine

The thesis deals with the study of spreading, harmfulness, biological properties of dry rot agents that is caused by Fusarium fungi. The influence of biotic and abiotic factors on the growth and development of dry rot agents as well as the character of their interrelations with some pathogens of the fungic and bacterial origin was established. It was proved that some Fusarium fungi species which on the basis of anatomical and morphological properties were identified as F. avenaceum, F. culmorum, F. gibbosum, F. macroceras, F. sambucinum, F. oxysporum and F. solani take part in the pathogenesis of the winter rot. Див продовження:Продовження: 9118. РефератIt was experimentally determined that in the interrelations of Fusarium species with Phytophthora infestans and Alternaria solani the growth and development inhibition of Fusaria by phytopathogeneous fungi - agents of phytophtorosis and alternariosis is not observed. However, when establishing the character of Fusaria relations with the agents of wet bacterial rot it was proved that Erwinia carotovora subsp. carotovora species inhibits development of Fusarium fungi creating inhibition zone, and Bacillus polymyxa and Pseudomonas fluorescens bacteria do not have negative influence when they are simulneously cultivated with F. culmorum, F. solani and F. oxysporum. When studying he influence of biotic and abiotic factors on the growth of winter rot agents the optimum temperature limits (20-25 oC) were established and the Rydomil Gold MC 68 WP, fungicide which completely inhibited development of F. culmorum, F. oxysporum and F. solani in the conditions in vitro was determined. When testing home and foreign selection variaties as to their resistance to dry rot of tubers, the relatively resistant varieties such as Adretta, Alvara, Borodyanska rozheva, Virineya, Dara, Dnipryanka, Zagadka, Kobza, Kosen 95, Lugovska, Svitanok kyyivsky, Serpanok, Slovyanka and Yavir which can be expediently used in the research institutions with conducting expedient selection as to this property have been singled out.