Banca de DEFESA: GINNA GONÇALVES PEREIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : GINNA GONÇALVES PEREIRA
DATE: 23/02/2024
TIME: 14:00
LOCAL: sala virtual do google meet
TITLE:

INSECTICIDAL ACTIVITY OF Varronia ESSENTIAL OIL
curassavica Jacq. ABOUT LARVAE OF Aedes aegypti (DIPTERA: CULICIDAE).

KEY WORDS:

Public health. Insect Vector. Botanical Insecticides. Essential oil.

PAGES: 74
BIG AREA: Outra
AREA: Ciências Ambientais
SUMMARY:

The Aedes aegypti mosquito is of great interest in studies on arboviruses, due to the damage to public health as it is the main transmitter of the dengue, chikungunya, yellow fever and Zika viruses. For years, this vector was restricted to some tropical regions and the viruses were endemic to them, but they are currently spreading to other subtropical and temperate regions. At this juncture, a continuous increase in the incidence of these arboviruses can be seen. Currently, there is an increase in
investments to control the insect vector, but these measures are increasingly difficult due to the indiscriminate use of synthetic chemical insecticides which, although they are effective, are polluting the environment and their specific action does not only reach the target organism, causing severe impacts environmental and human health. Therefore, botanical insecticides appear with the aim of reducing this damage. Therefore, with this research, we sought to evaluate the insecticidal effect of Varronia curassavica Jacq essential oil. (whale weed) on larvae of Ae. aegypti. The essential oil was obtained by the hydrodeslitation method in a Clevenger-type device and its chemical constitution was made through gas chromatography coupled to a mass spectrometer (GC/MS). In bioassays, 20 larvae were used per test, in disposable cups with a volume of 25 ml each. The tests were carried out in four concentrations, with four repetitions each, plus a positive test, containing the synthetic insecticide pyriproxyfen at a commercial concentration and a negative test, containing only distilled water. The essential oil killed 100% of the larvae at the highest concentration (0.125% ) in 24 hours. At 0.0625%, mortality varied between 77.5% in 24 hours, 96.3% in 48 hours and 100% in 72 hours. While at concentration 0.0312%, a result of 63.7% mortality was obtained in 24 hours and 90 and 95% in 48 and 72 hours, respectively. For the lowest concentration (0.0156%), mortality was 37.5, 51.2 and 25.5% at 24, 48 and 72 hours,
respectively. In order to analyze the Lethal Concentrations (LC), the LC10 was calculated, with a value of 0.003%, the LC50 of 0.014% and the LC90 of 0.031%, values that are, considerably, below the minimum, average and maximum concentrations of the tested oil. The main constituents found in Varronia curassavica oil were (E)-Caryophyllene, Bicyclogermacrene and δ-Cadinene, probably responsible for the mortality of Aedes aegypti larvae. The results demonstrate the insecticidal potential of V. curassavica essential oil in controlling Ae. aegypti, especially as this is unprecedented data for this plant species.

COMMITTEE MEMBERS:
Externo à Instituição - JOSÉ WEVERTON ALMEIDA BEZERRA - UFPE
Interna - ESTELITA LIMA CANDIDO
Presidente - FRANCISCO ROBERTO DE AZEVEDO
Externo à Instituição - SAULO RELISON TINTINO - UFPE