RIZOBACTÉRIAS COMO AGENTES DE BIOCONTROLE DA PODRIDÃO MOLE EM BATATA

Abstract

Potato (Solanum tuberosum L.) cultivation is highly relevant in Brazil, serving various purposes ranging from industrial processing to fresh consumption. One of the main challenges faced by producers in obtaining these tubers is disease management, especially those of bacterial origin, such as soft rot, which compromise productivity. Biological control is an important tool in disease management, progressively standing out as a sustainable and increasingly viable alternative. Rhizobacteria isolated from cultivation areas where interaction with the crop has already been established are promising agents in the control of phytopathogens. The objective of this work was to evaluate the efficiency of using rhizobacteria as antagonists to the genera Dickeya and Pectobacterium, through assays conducted in a humid chamber. Eighteen bacteria were tested against the phytopathogen Dickeya spp., and among these, 12 against Pectobacterium spp., collected from potato cultivation areas. Treatments with each bacterial isolate were evaluated in triplicate. Rhizobacteria LFB11, LFB10, and LFB18 showed the best results in suppressing Dickeya spp. in potato tubers, with values statistically similar to the negative control (without inoculation of the phytobacteria). Isolates LFB1, LFB2, LFB6, LFB7, LFB9, LFB10, LFB11, and LFB12 showed efficiency for both phytopathogens, demonstrating effectiveness in reducing or inhibiting infection regardless of the causal agent. These isolates demonstrated high biocontrol potential for soft rot, possibly due to antagonistic mechanisms, such as the production of antimicrobial metabolites and competition for nutrients and infection sites.