Fungicide Resistance of Russian Phytophthora infestans strains

SUMMARY P. infestans strains have been isolated in pure culture from blighted samples, collected in the Moscow, Leningrad, Astrakhan, Smolensk, and Kostroma regions, Mariy El Republic, and Belarus. The fungicide resistance of collected strains has been tested in Petri dishes with agar medium. The most efficient fungicides are azoxystrobin and dimethomorph. The efficiency of fluazinam, chlorothalonil, and mancozeb is also rather high. Therefore, the application of these fungicides in recommended dosages can provide a successful potato late blight control. The strains, highly resistant to metalaxyl, has been revealed in the Moscow and Smolensk regions, and also in Belarus.