INOCULATION OF Rhizophagus intraradices AND SOIL PATHOGENS IN SOYBEAN GROWN IN THE CERRADO

Resumo

The Brazilian Cerrado, known for its extensive arable areas and favorable climate conditions, plays a crucial role in the production of soybeans, a crop essential to global food security. However, the productivity of this crop is often compromised by soil diseases that negatively impact its development. The use of Arbuscular Mycorrhizal Fungi (AMF), such as Rhizophagus intraradices, emerges as a promising alternative for the integrated management of soil diseases. This work aims to investigate the effect of inoculating the arbuscular mycorrhizal fungus (AMF) Rhizophagus intraradices on the population of soil pathogens and the health of soybean plants grown in the Cerrado. The experiment was conducted using a completely randomized design with treatments in a 2x5 factorial scheme. The first factor was inoculation with Rhizophagus intraradices versus a control treatment without inoculation. The second factor consisted of areas with the occurrence of five soil-borne pathogens: Cercospora ssp., Curtobacterium flaccumfaciens, Fusarium oxysporum, Sclerotinia sclerotiorum, and Rhizoctonia solani. Inoculation was applied via seed treatment. During the R3 soybean cycle, samples of rhizospheric soil and roots were collected for analysis in the laboratory, where AMF spores and soil pathogens were identified and quantified using molecular and microbiological methods. Inoculation with Rhizophagus intraradices resulted in a significant reduction in the populations of Fusarium oxysporum and Rhizoctonia solani, but did not significantly affect the populations of Cercospora ssp, Curtobacterium flaccumfaciens, and Sclerotinia sclerotiorum. The diversity of identified native AMF genera was also greater in inoculated areas. Inoculation of soybeans with Rhizophagus intraradices has demonstrated to be a promising strategy for the biological control of soilborne pathogens, particularly Fusarium oxysporum and Rhizoctonia solani.