Influence of the Potato Production System in the Soil Suppressiveness to Bacterial Wilt

The potato crop is highly affected by soil-borne diseases motivating its continuous migration to non-cultivated areas. Bacterial wilt caused by Ralstonia spp. is one of the main diseases affecting the potato crop in Brazil, since the conventional production system, used throughout the country, promotes an ideal environment for proliferation of members of this pathogen complex. Studying alternative potato production systems aiming to improve the soil biological properties is necessary in order to avoid the continuous migration of the potato crop to new areas. The objective of this work was to evaluate different potato production systems, namely, the Paces an alternative potato production system and the organic potato production systems in contrast to the conventional production system, a soil from the Paces system sterilized through autoclaving and an undisturbed Atlantic rainforest soil regarding the soil suppressiveness to bacterial wilt caused by R. solanacearum. The experimental design was randomized blocks with three replications, arranged in a 4 x 4 + 1 factorial scheme, the main factor being the production system and the secondary factor corresponding to the doses of soil contaminated with R. solanacearum added to each treatment (0, 25, 50 and 75%). The additional treatment corresponded to the soil of the conventional system with high incidence of R. solanacearum. The soil suppressiveness to bacterial wilt is a biological process inhibited by autoclaving. The Paces and the organic potato production systems have a significant potential to suppress R. solanacearum in infested soil.