ANTIFUNGAL ACTIVITY OF ROSEMARY EXTRACT ON MACROPHOMINA PHASEOLINA AND CHARCOAL ROT CONTROL IN SOYBEAN
E. Lorenzetti, J.R. Stangarlin, O.J. Kuhn
The charcoal rot caused by the fungus Macrophomina phaseolina is an important disease of soybean (Glycine max), for which there is no recommended fungicides or resistant cultivars. The aim of this study was to investigate the antifungal activity and the control of charcoal rot of soybean stem with an aqueous extract of rosemary at concentrations of 1%, 2.5% and 5%. The in vitro assays were carried out to evaluate the mycelial growth and the production of micro-sclerotia in solid and liquid culture media, while in vivo assays evaluated the disease progress. The rosemary extract reduced the fungal growth on solid and liquid media by 44% and 74%, respectively, and the number of micro-sclerotia by 61%. There was a disease reduction of 53% and 56% in the area under the disease progress curve in the first and in second assay, respectively. These results indicate the potential of the rosemary extract for controlling charcoal rot in soybean.