In vitro antimicrobial activity of methanolic extracts from cutaneous secretions of Amazonian amphibians against phytopathogens of agricultural interest

ABSTRACT The biochemical defense mechanisms of amphibians involve cutaneous secretions bioactive molecules with antimicrobial activity. This study evaluated the in vitro activity methanolic extracts from two amphibian species Bufonidae family, Rhaebo guttatus and Rhinella marina, control phytopathogens Fusarium udum, solani, Colletotrichum truncatum, Aspergillus flavus, Rhizoctonia Macrophomina phaseolina, Calonectria pseudometrosideri. R. extract decreased mycelial growth F. A. M. phaseolina at some tested concentrations. marina C. truncatum concentration 0.5 mg mL-¹, inhibited flavus concentrations 0.1 which was similar to inhibition by positive control. also microsclerotia production solani 0.2 0.3 mL-¹. In addition, conidial sporulation germination varying degrees. appressoria formation 85-99% 63-100%, respectively. Our results demonstrated that treatment showed antifungal against studied phytopathogens.