Banca de DEFESA: AMANDA LAYSA SILVA NASCIMENTO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : AMANDA LAYSA SILVA NASCIMENTO
DATE: 20/02/2024
TIME: 14:30
LOCAL: Departamento de Química - Sala de Auditório
TITLE:

EVALUATION OF THE ACARICIDAL POTENTIAL OF COMPOUNDS PRESENT IN ESSENTIAL OILS OF PLANTS FROM THE FLORA OF PERNAMBUCANA ON Tetranychus urticae

KEY WORDS:

Acaricidal activity, essential oils, binary mixture, Tetranychus urticae, repellency, residual contact.

PAGES: 77
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:

Tetranychus urticae (Koch) is a cosmopolitan and polyphagous pest, considered one of the main agricultural pests worldwide. Its control is mainly carried out by the application of commercial acaricides such as Orthus® and Azamax®, which cause environmental contamination, damage to non-target organisms and contribute to the development of resistant populations of the pest. As an alternative to commercial mites, botanical acaricides based on essential oils (EOs) and their main constituents have been used to control T. urticae. In this way, the search for new alternatives based on EOs and compounds derived from them is important to minimize the emergence of resistant populations. The properties observed for EOs are attributed to their main constituents. However, the property observed for a given oil cannot be attributed solely to the majority constituent since the toxicity of the oil can be increased due to interactions between the constituents in smaller percentages. At this stage of the work, the toxicity of more than 50 compounds from the monoterpene class (α-pinene and geraniol), phenylpropanoid (safrole) and diterpene (phytol) was evaluated. Among the compounds tested, phytol revealed the greatest toxicity against T. urticae, with a mortality of 100% at a concentration of 0.5μL/mL. Tests were carried out to investigate the lethal and sublethal acaricidal potential, through the residual and ovicidal contact bioassay of binary mixtures obtaining medium lethal (LC₅₀) and sublethal concentrations, evaluating hatching and oviposition against the two-spotted mite. All compounds and binary mixtures were shown to be toxic to T. urticae through the residual contact bioassay, with the best results observed for the mixtures 30% phytol and 70% safrole (LC₅₀= 2.16 µL/mL), 10% phytol and 90% safrole (LC₅₀= 3.38 µL/mL). For the bioassay of ovicidal residual contact mixtures, all binary mixtures acted strongly on the eclosion of T. urticae, within 48 hours.

COMMITTEE MEMBERS:
Presidente - MARCILIO MARTINS DE MORAES
Interno - CLAUDIO AUGUSTO GOMES DA CAMARA
Externa à Instituição - CAROLINA ALVES DE ARAUJO - UFRPE
Externo à Instituição - RODOLFO RODRIGUES DA SILVA - UFRPE