Banca de QUALIFICAÇÃO: JÉSSICA FERNANDA DOS SANTOS BARROSO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JÉSSICA FERNANDA DOS SANTOS BARROSO
DATE: 29/02/2024
TIME: 09:00
LOCAL: Sala Virtual Remota (Microsoft Teams) https://bit.ly/QualMsc_JéssicaFernanda_PGBIOEXP
TITLE:

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KEY WORDS:

Mansonia; Insectary; Biolarvicides; Biological control; Persistence

PAGES: 75
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

Biolarvicides are agents that stand out worldwide in the biological control of mosquitoes of medical importance, reinforcing the initiative of harmless control and thus avoiding the accelerated use of chemical means, which minimizes problems related to resistance in various mosquito species. Given this versatility, we evaluated the effectiveness of two products, Vectobac-WG® and Vectomax-FG®, against the larvae of two species of Mansoniini in the laboratory. First-stage larvae (L1) of Ma. humeralis and Ma. titillans were obtained from field females and L1 larvae of Aedes aegypti from the laboratory were used as a comparison parameter for bioassays, which followed the World Health Organization (WHO) protocol (with adaptations), in an environment with controlled temperature (T) and relative humidity (RH) (T 25 - 27ºC / RH -70 - 80%). Different concentrations of Vectobac-WG 3. 000 UTI/mg (0.00025ppm, 0.0005ppm, 0.001ppm, 0.002ppm, 0.004ppm and 0.008ppm), and Vectomax-FG 50 UTI/mg (0.00031ppm, 0.00062ppm, 0.00125ppm, 0.0025ppm, 0.005ppm and 0.01ppm) were tested as larvicides using 50 L1 larvae in triplicates, with four repetitions at different times. Larval mortality was monitored for up to 48 hours. The persistence of the same products was tested in two lighting conditions (light and dark) for 35 days. The dose-effect and persistence of the products on the larvae were analyzed using the Kruskal-Wallis test (non-parametric ANOVA), and Dunn's test was used for multiple comparisons at a 5% significance level. To obtain the lethal concentrations (CL50 and CL90) after 24 and 48 hours, Probit analysis was carried out (concentration x mortality). Vectobac-WG caused an average mortality of 61.1% for Ma. humeralis, 70.8% for Ma. titillans and 37.7% for Ae. aegypti. Treatment with Vectomax-FG resulted in mortality of 50.1% for Ma. humeralis, 53.7% for Ma. titillans and 51.1% for Ae. aegypti. The estimated lethal concentrations (LC) of Vectobac-WG for Ma. humeralis and Ma. titillans were LC50 from 0.0004ppm to 0.0008ppm and LC90 from 0.0019ppm to 0.0029ppm, respectively. The CLs estimated for Vectomax-FG for Ma. humeralis and Ma. titillans were higher, i.e., CL50 0.0016ppm to 0.0018 ppm and CL90 0.0051ppm to 0.0061ppm, respectively. After an evaluation of 5 weeks from the start of application in the laboratory, the product Vectomax-FG caused mortality of > 66% up to the 3rd week for the two lighting conditions evaluated and Vectobac-Wg caused larval mortality of more than 50% under the use of direct light up to the 3rd week, this product showed mortality of 43% up to the 2nd week in the dark. In view of the results, we concluded that the larvae of Ma. humeralis and Ma. titillans were susceptible to the products Vectobac-WG and Vectomax-FG. The mortality of the larvae depended on the concentration of the product used, the type of bacilli and the species of mosquito used. The products persisted for 21 days, with mortality ranging from 100% to 58%. From the second week onwards, there was a noticeable difference between the lighting conditions.

COMMITTEE MEMBERS:
Externo à Instituição - FRANCISCO AUGUSTO DA SILVA FERREIRA - INPA
Presidente - ***.446.996-** - GENIMAR REBOUÇAS JULIÃO - UNIR