Effect of bacterium Pseudomonas fluorescens and low fungicide dose seed treatments on parasite fungus Apharomyces cochlioides and sugar beet yield and quality

The aim of this study was to evaluate whether the application of Thiram 42-S and Dithane S-60 aiming to control Aphanomyces cochlioides, a pathogenic fungi causing root decay, and a simultaneous inoculation of sugar beet seeds with Pseudomonas fluorescens has an effect on sugar beet yield and quantity. Experiments were carried out on two soil types, Mollic Gleysols and Eutric Cambisol, and lasted 3 years. The highest average sugar beet root yield (85.15 t/ha), the highest average sugar concentration (16.39%) and the highest average sugar yield value (12.79 t/ha) were obtained with the combination Thiram 42-S + P. fluorescens. However, concerning the yield, there were no significant differences between the above-mentioned variant and the one with seed inoculated only with P. fluorescens (84.63 t/ha). The highest percentage of infected and decayed plants (on both soil types) was reported in the control variant (28.92% infected and 25% decayed plants on average), whereas the lowest one was detected when seeds were inoculated with P. fluorescens and treated with Thiram 42-S (4.70% infected and 2.88% decayed plants).