Controle alternativo de macrófitas aquáticas infestantes de reservatórios

Abstract

Observing all economic losses, social and environmental impacts caused by the extreme proliferation of aquatic macrophytes in reservoirs, besides Brazil being a country with great importance in electric power generation from Hydroelectric Power Plants. This work had as objective to develop potential bioherbicides from microorganisms, obtaining the production of phytotoxins for use in biocontrol of aquatic macrophytes.The experiment was installed in a completely randomized design (CRD) with 3 replicates for each treatment, plus the control; using 3 species of aquatic macrophytes, Eichhornia crassipes, Pistia stratiotes e Salvinia herzogii. Visual evaluations were carried out at 2, 5, 8, 10, 15 days after treatment (DAT), using a percentage scale of notes, where 0% represented no control and 40% control of the plants, the same evaluation days were used to verify the fresh mass. By the selection technique, three fungi were selected, Trichoderma spp., Verticilliuml spp. e Paecilomyces spp., producing 4 bioherbicides, one with interaction of two fungi, Trichoderma spp + Verticillium. By evaluating the results, it was possible to identify that in the visual, the main damages were caused only in one of the species (Pistia stratiotes) and in 2 treatments(Paecilomyces e Verticillium), with greater incidence between the second and fifth day after application of the bioherbicide. For fresh mass, similarly, only one of the species obtained results, having three (Paecilocyces, Trichoderma e Verticillium) of the four treatments with a significant result in relation to the control.