Banca de DEFESA: RODRIGO BASTOS DOS SANTOS
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.STUDENT : RODRIGO BASTOS DOS SANTOS
DATE: 08/07/2022
TIME: 14:00
LOCAL: Videoconferência
TITLE:
INSECTICIDE AND ANTIOXIDANT POTENTIAL OF ESSENTIALS OILS OF SPECIES FROM THE GENUS Eugenia (Myrtaceae) ON THE DIAMONDBACK MOTH (Plutella xylostella)
KEY WORDS:
Chemical composition; Lethality; Antioxidant action; Eugenia; Plutella xylostella.
PAGES: 76
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:
Agricultural crops constantly suffer damage caused by pest insects, the lepidopterans, in turn, have caused substantial losses to producers. Plutella xylostella is the most important harmful species to the agricultural development of Brassicas, having as main control mechanism the use of chemical insecticides, which have shown resistance development, besides soil contamination and toxicity on non-target organisms. The present work aims to investigate the insecticidal potential of the essential oils from the leaves of different species of Eugenia, on the moth of crucifers, besides reporting their antioxidant action and chemical composition. The oils from Eugenias, showed yields ranging from 0.05% to 0.82%, besides being characterized with a high profile of sesquiterpenes. The caryophyllene oxide (25.20%) took the majority position in E. dysenterica oil, while the terpenoid longipinanol (15.01%) in E. klotzschiana, as well as spatulenol (12.71%) for E. langsdorffii was the main constituent, the oxygenated sesquiterpene curzerene (37.52%) was revealed for E. uniflora, while E-caryophyllene (51.39%) for E. uvalha. All EOs showed lower antioxidant action than controls by DPPH and ABTS method, which showed low free radical scavenging capacity. The results obtained in the larval toxicity bioassay showed, for E. uniflora leaf oil, a mean lethal concentration of 1.88 μL/mL, which showed higher lethal potential than the commercial products Azamax® (LC50 = 5.04 μL/mL) and Decis® (LC50 = 9.24 μL/mL). The other Eugenia oils showed higher values in this test. On the egg stage of P. xylostella, the treatments used proved to be more toxic, pitangueira (LC50 = 0.02 μL/mL) reaffirmed its higher lethality while E. dysenterica (LC50 = 1.28 μL/mL) and Azamax® (LC50 = 1.07 μL/mL) did not differ statistically. In the analysis of the feeding deterrent effect, E. klotzschiana showed an attractive effect, while cagaita (DA50 = 0.15 μL/mL), pitanga (DA50 = 0.13 μL/mL) and uvaia (DA50 = 0.15 μL/mL) reduced feeding by 50%, but did not differ statistically.
BANKING MEMBERS:
Presidente - 980615 - CLAUDIO AUGUSTO GOMES DA CAMARA
Interno - 1508305 - JOAO RUFINO DE FREITAS FILHO
Interno - 3133784 - MARCILIO MARTINS DE MORAES
Externa ao Programa - 065.662.504-09 - VANESKA BARBOSA MONTEIRO - UFRPE