Potencial nematicida de Bacillus velezensis e seus metabólitos secundários no controle de Meloidogyne incognita

Abstract

Soybean is one of the main agricultural commodities in Brazil; however, its productivity can be reduced by the action of plant-parasitic nematodes, especially Meloidogyne incognita, which is responsible for the formation of root galls and significant economic losses. Given the limitations of conventional control methods, biological agents have emerged as more sustainable alternatives. In this context, the present study aimed to evaluate the biological activity of Bacillus velezensis on different developmental stages of M. incognita through the use of a fermented suspension for the control of secondstage juveniles (J2), as well as cell suspensions and extracellular metabolites from different strains to assess egg hatching, aiming at their applicability in the sustainable management of soybean crops. The study was conducted at the Biological Control Laboratory II of the Federal University of Technology – Paraná (UTFPR), at the Dois Vizinhos Campus, and at a partner laboratory specialized in nematology. In vitro assays of juvenile mortality and egg hatching were carried out using a completely randomized design with 4 replications. The experimental data were subjected to the Scott-Knott test at a 5% probability level. The results demonstrated that B. velezensis induced high mortaly in M. incognita juveniles, indicating significant nematicidal activity against pathogen's mobile stages. However, the treatments did not show a significant effect on egg hatching under the evaluated conditions. Therefore, the findings indicate the potential of B. velezensis for the biological control of M. incognita, particularly against infective juveniles, highlighting the need for further studies involving concentrations, application methods, and the biological availability of metabolites.