Laboratory evaluation of Dalbergia oliveri (Fabaceae: Fabales) extracts and isolated isoflavonoids on Aedes aegypti (Diptera: Culicidae) mosquitoes

Abstract The yellow fever mosquito, Aedes aegypti (Diptera: Culicidae) transmits several devastating arboviruses, including dengue, chikungunya, and Zika virus, making development of inexpensive and eco-friendly strategies for its control an urgent priority. We evaluated the lethality of 13 commonly used plant-derived edible oils against late-third instar Ae. aegypti and then tested the three most lethal oils for stage-specific differences in lethality. We also examined the effects of the most lethal (hempseed), moderately lethal (sunflower and peanut), and least lethal (olive) oils on survival to adulthood and oviposition behavior of gravid females. We hypothesized that the insecticidal activity of edible oils is a function of the content of their linoleic acid, a key fatty acid component with film-forming properties. Among the 13 oils tested, hempseed oil was the most lethal, with an LC50 of 348.25 ppm, followed by sesame (670.44 ppm) and pumpkinseed (826.91 ppm) oils. Oils with higher linoleic acid content were more lethal to larvae than those with low linoleic acid content. Furthermore, pure concentrated linoleic acid was more lethal to larvae compared to any edible oil. In comparison to early instars, late instars were more susceptible to hempseed, sunflower, peanut, and olive oils; these oils also acted as oviposition deterrents, with effective repellency ≥63%. The proportion of larvae surviving to adulthood was significantly reduced in hempseed, sunflower, peanut, and olive oil treatments relative to controls. Our results suggest that some edible plant oils have potential as effective, eco-friendly larvicides, and oviposition deterrents for controlling container-dwelling mosquitoes, especially in resource-limited settings.

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Laboratory evaluation on the efficacy of Bacillus thuringiensis var. israelensis Berliner 1915 (Bacillaceae) on the instars of the dengue vector Aedes aegypti Linnaeus 1762 (Diptera: Culicidae) and against the adults of Diplonychus indicus Venk. & Rao (Hemiptera: Belostomatidae) as non-target organisma

Acta Entomology and Zoology ◽

10.33545/27080013.2020.v1.i1a.7 ◽

2020 ◽

Vol 1 (1) ◽

pp. 39-43

Author(s):

Grace Marin ◽

Subramanian Arivoli ◽

Selvanayagam Selvakumar ◽

Samuel Tennyson

Keyword(s):

Bacillus Thuringiensis ◽

Aedes Aegypti ◽

Laboratory Evaluation ◽

Dengue Vector

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LABORATORY EVALUATION OF THE DEVELOPMENT OF Aedes aegypti IN TWO SEASONS: INFLUENCE OF DIFFERENT PLACES AND DIFFERENT DENSITIES

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652014000500001 ◽

2014 ◽

Vol 56 (5) ◽

pp. 369-374 ◽

Cited By ~ 6

Author(s):

Tatiana Forte Lopes ◽

Marcia Moreira Holcman ◽

Gerson Laurindo Barbosa ◽

Maria de Fatima Domingos ◽

Rosa Maria Oliveira Veiga Barreiros

Keyword(s):

Aedes Aegypti ◽

Water Temperature ◽

Median Time ◽

Time Development ◽

Laboratory Evaluation ◽

Southeastern Brazil ◽

Survival Curves ◽

Coastal City ◽

Individual Experiment ◽

The Individual

Aedes aegypti is an important vector in Brazil being the main vector of the dengue-fever. This paper employs survival curves to describe the time in days from larvae to adult forms of Aedes aegypti raised, individually and collectively, and compares it during winter and spring when positioned inside and outside a laboratory. The study was conducted in São Vicente, a coastal city in Southeastern Brazil. The lowest water temperature in winter and in spring was 20 °C and the highest was 26 °C in spring. Higher and more stable temperatures were measured in the intra compared to the peri in both seasons. Consequently, larvae positioned in the intra resulted in the lowest median time to develop in the individual and collective experiment (nine and ten days, respectively). At least 25% of the larvae positioned in the intra in the individual experiment in the spring took only seven days to reach adulthood. Sex ratios and the median time development by sex did not show significant differences. These results indicate that efforts to control Aedes aegypti must be continuous and directed mainly to prevent the intra-domiciliary sites that can be infested in a week in order to reduce the human-vector contact.

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