Overcoming the potato cultivar tuber resistance by the agents of main potato diseases in dependence from changes of mycological features of pathogens

At different regions of Russia, potato crop is affected with different diseases, late blight, early blight, fusariosis are prevailing among them. Potato losses caused with these diseases go to 50-60%. Leading role at their suppression should be associated with complex cultivar resistance. It provides good potato yields. Aim of our investigation is an estimation of potato cultivars with different resistance to the agents of potato late blight, early blight and fusariosis. Cultivar resistance is principal factor at pathogen aggressiveness manifestation. Our investigation revealed potato cultivars with high leveled tuber resistance (Nikulinsky, Udacha). Also some cultivars (Sante) inappropriate to manifested characteristics. Pathogen propagules were found to be the primary factor influencing the pathogen aggressiveness manifestation. A high their concentration provides a high leveled aggressiveness. Currently, aggressiveness of Phytophthora infestans, Alternaria alternata, Fusarium oxysporum was investigated depending from cultivar, kind of inoculation and concentration of zoosporangia and conidia. Tuber disks of potato cultivar Nikulinsky were affected with all pathogens at minimal level. Tuber disks of potato cultivar Avrora were affected with Fusarium oxysporum conidia and chlamydospores at maximal level. According to the data obtained, potato cultivars with high leveled field resistance such as Nikulinsky, Udacha should be practically used with joint assessment of populations of potato pathogens.

фитофтороз картофеля, альтернариоз картофеля, агрессивность, фузариоз картофеля, Phytophthora infestans, Alternaria alternata, Fusarium oxysporum, potato late blight, potato early blight, potato fusariosis, aggressiveness, Phytophthora infestans, Alternaria alternata, Fusarium oxysporum