Antimicrobial activity against Macrophomina phaseolina and the control of charcoal rot in soybeans using the homoeopathic drugs Sepia and Arsenicum album

Abstract

The aim of this study was to evaluate the control of charcoal rot in soybeans using Sepia and Arsenicum album homeopathic solutions in dynamizations of 6, 12, 24, 36 and 48CH (hahnemanian centesimal scale), in addition to verify the antimicrobial activity of these treatments against Macrophomina phaseolina. Additional treatments were also used, including distilled water and a hydroalcoholic solution of 30% ethanol. In vitro tests were performed to analyze the number of micro-sclerotia and the mycelial growth of the fungus. In vivo assays were used to evaluate the progress of the disease and the size of the lesions. For the area under the mycelial growth curve (AUMGC), A. album had no effect, however, Sepia reduced up to 32% of the fungal growth. For micro-sclerotia there was no statistical difference. For the area under the disease progress curve (AUDPC), both Sepia and A. album in 24CH dynamization reduced fungal growth up to 50% and 70% in the first and second assays, respectively, compared to control treatments. These results indicate the potential of these homeopathic drugs for controlling soybean charcoal rot.