Atividade fitotóxica de extratos de frutos do cerrado

Abstract

Some plant species have phytotoxic activity (bioherbicides) because they have bioactive compounds with the ability to inhibit the development of other plants. In this work, we aimed to evaluate the extracts and fractions of the fruits of caraguatá (Bromelia balansae), guavira (Campomanesia adamantium), ingá (Inga laurina) and passion fruit (Passiflora gibertii) have phytotoxic activity. The experimental design used was completely randomized, in which we used solutions of extracts and fractions at concentrations of 0, 250, 500 and 1.000 mg L-1 . We evaluated the phytotoxic effect of extracts and fractions on germination speed index, germination percentage, root and shoot length and total dry mass of lettuce and onion seedlings. All fruits evaluated in this study showed phytotoxic effect. We can highlight as the most relevant results the hexane fraction of guavira fruits, the ethyl acetate fraction of passion fruit fruits, which inhibited lettuce germination and the hexane fraction of caraguatá in onion. The greatest inhibition of growth was observed in the hexane fraction of guavira in lettuce and ethyl acetate fraction of ingá in onion. The compounds present in caraguatá, guavira, ingá and passion fruit fruits show phytotoxic activity and can be used as alternative bioherbicides less harmful to the environment.