INFLUÊNCIA DE EXTRATO VEGETAL DAS FOLHAS DE SUCUPIRA (Pterodon emarginatus) NO CONTROLE DE Ditylenchus gallaeformans

Abstract

The nematode of the species Ditylenchus gallaeformans, causal agent of galls and deformations in aerial tissues of ornamental plants of the family melastomataceae, like the species of micônias. The use of plant extracts has been widely used for studies of their biological activities, in different types of control, for both insects and microorganisms that cause plant diseases. The central-west region has great potential in relation to varieties and diversification of plants with therapeutic potential and control of phytopathogens, including nematodes. Considering this

importance, some species considered native to the Cerrado region were chosen to perform a pre- test, and to be able to choose which would be the best option for the development of the work.

Sucupira was the species chosen because it is a popular plant of Cerrado and has some proven medical importance. The test was performed under laboratory conditions using the completely randomized design, with 4 treatments (concentrations of the sucupira leaf extract) plus the control (distilled water) and six replicates. The extract was obtained through exhaustive percolation with ethyl alcohol 95%, and concentrated in a rotary evaporator. After obtaining the crude extract, it was fractionated in increasing concentrations in the following order: 12.5 ppm; 25 ppm; 50 ppm and 100 ppm. Test tubes and petri dishes were used, and each treatment consisted of 1.5 mL of solubilized extract in 1% DMSO, respectively and 1 mL of the solution containing 300 (J2) of Ditylenchus gallaeformans. After 48 hours, the number of dead J2 was quantified, in other words, those that were immobile after the addition of NaOH N1 at 20%. The confirmation of the death of the J2 was made by the microscopic photonic count of the nematodes that were in the stretched and immobile positions. A significant reduction in the number of live nematodes in the different treatments compared to the control treatment was observed. Starting from the concentration of 50 ppm, deaths of 95% of the J2 of Ditylenchus gallaeformans were caused. This result is evidence that the ethanolic extract of the sucupira leaves has the potential to be used in the control of the gall nematodes of the micônia leaf.