EXTRATOS ATIVOS DE PIPER ADUNCUM L., SOBRE OS FUNGOS SCLEROTINIA SCLEROTIORUM (LIB.) DE BARRY, COLLETOTRICHUM GLOEOSPORIOIDES (PENZ.) SACC. E RHIZOPUS STOLONIFER (EHRENB. FR.) VUILL., TESTE IN VITRO E IN VIVO EM SOJA

Abstract

Agrochemicals based on secondary plant metabolites, such as plant extracts, are an alternative for controlling fungi of agronomic importance, as they are less toxic, biodegradable, and safer for the environment. Piper aduncum L., is a plant from tropical regions belonging to the Piperaceae family with important biological activities against insects, bacteria and fungi. In this context, the objective of this work was to evaluate the antifungal activity of hexane extracts from the leaves and influorescences of Piper aduncum on the agricultural fungi Sclerotinia sclerotiorum, Colletotrichum gloeosporioides and Rhizopus stolonifer, to determine the chemical composition of the extracts and to test the in vitro and in vivo in soybean culture. The major compounds identified in the hexane leaf extract were: germacrene B (33.1%), valencene (14.5%), β-cadinene (9.1%), α-humulene (8.1%) and β-cubebene (6.5%). In the inflorescence extract the predominant compounds were: viridiflorol (20.5%), spathulenol (15.2%), germacrene B (9.7%), α-cubebene (8.2%) and valencene (6.4%). The in vitro antifungal activity demonstrated that the hexane extract of the flowers showed greater antifungal activity with the studied fungi. In vivo tests with the most active concentrations, it can be concluded that Piper aduncum, in particular the extract of the inflorescences, has potential for use in the integrated management of diseases in soybeans, reducing the severity of the white mold disease, probably if its major compounds are isolated. The author is grateful to the Maranhão Research Support Foundation (FAPEMA)