During two-year studies on two different soil types (Mollic Gleysols, Calcaric Fluvisols) in 4 repetitions and 4 different variants, as follows: 1. untreated seed ; 2. Dithane S- fungicide treated seed (60% Mancozeb, 800 g 100 kg-1 seed) ; 3. seed treated with fungicide Dithane S (60% Mancozeb, 400 g 100 kg-1 seed) + inoculated with Bacillus megaterium (0.6 x 1010 bacteria ha-1) ; 4. seed inoculated with Bacillus megaterium (1.2 x 1010 bacteria ha-1) we investigated influence of different seed treatments to infection with pathogenic fungi Pythium ultimum and Pythium debarianum, as well as, elements of sugar beet yield (root yield, sugar content). The best results were obtained by inoculation of sugar beet seed with the bacterium B. megaterium.

Agriculture