Biocontrole de fitonematoides: o protagonismo de Bacillus spp. na produção de soja

Abstract

Soybean (Glycine max L.) has consolidated itself as the main commodity of Brazilian agribusiness; however, its yield potential is severely limited by the incidence of phytonematodes, whose economic losses reach R$ 16.2 billion annually. This study analyzed, through a literature review, the role of rhizobacteria of the genus Bacillus spp. in the integrated management of Heterodera glycines, Meloidogyne spp., and Pratylenchus brachyurus. The results highlight the effectiveness of the species B. subtilis, B. firmus, B. amyloliquefaciens, B. methylotrophicus, and B. thuringiensis in controlling these phytopathogens. The efficiency of these biological agents is attributed to their multifunctional action, which includes direct antagonism through metabolites and crystalline proteins, induction of plant resistance, and promotion of plant growth. It was observed that maximum suppression of phytonematode populations occurs when biological control is combined with cultural management practices using cover crops, such as species of the genera Brachiaria and Crotalaria, which act as non-host or antagonistic crops by interrupting the biological cycle of phytonematodes. It is concluded that the integration of Bacillus spp. represents a highly viable biotechnological solution, essential to ensure the resilience and profitability of national soybean production in the face of the phytosanitary challenge imposed by phytonematodes