Comparative pharmacological characterization of D1-like dopamine receptors from Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus suggests pleiotropic signaling in mosquito vector lineages

Five media, formulated from dried cow blood, mineral salts, and seeds from four species of legumes, were assessed for growth, sporulation, and insecticidal properties of Bacillus sphaericus strain 1593. Bacterial powders, prepared from broth, were assayed against Culex quinquefasciatus, Anopheles gambiae, and Aedes aegypti. Good growth and sporulation were obtained with all the media. The highest number of viable cells and spores per millitre (8.6 × 108 and 8.1 × 108) were obtained in media containing ground seeds of Vignia unguiculata, Voandzeia subterranean, and Arachis hypogea. All powders were effective against C. quinquefasciatus and A. gambiae. Powders from media containing Arachis hypogea were the most effective with LC50's of 4.344 × 10−3 ± 1.650 × 10−4 and 0.193 ± 1.376 × 10−2 μg/mL for C. quinquefasciatus and A. gambiae, respectively. Aedes aegypti larvae were only slightly susceptible to the powders. This investigation shows that these media can be used for the production of B. sphaericus 1593 primary powder.

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Effectiveness of Three Fruit Seed Extracts as Larvicide against Three Major Mosquito Vectors Aedes aegypti Linnaeus, Culex quinquefasciatus Say and Anopheles gambiae Giles (Diptera: Culicidae)

International Journal of TROPICAL DISEASE & Health ◽

10.9734/ijtdh/2020/v41i2330415 ◽

2020 ◽

pp. 16-29

Author(s):

Lame Younoussa ◽

Kary Mallam Oumarou ◽

Theodora Kopa Kowa ◽

Serge Eteme Enama ◽

Gabriel Agbor Agbor ◽

...

Keyword(s):

Aedes Aegypti ◽

Anopheles Gambiae ◽

Culex Quinquefasciatus ◽

Tap Water ◽

Mosquito Species ◽

Mangifera Indica ◽

Larval Mortality ◽

Persea Americana ◽

Plant Seed ◽

Seed Extracts

The CH2Cl2-MeOH (30:70 v/v) extracts of the seeds of Mangifera indica (Mango), Persea americana (Avocado) and Dacryodes edulis (African plum) were evaluated for potential mosquito larvicidal activity against 3rd and 4th instar larvae of Aedes aegypti, Culex quinquefasciatus and Anopheles gambiae. Extracts were diluted with 1 mL of methanol and concentrations ranging from 1000 to 125 mg/L in 4 replicates each, were prepared in the volume of 100 mL in the plastic cups (250 mL). A volume of 1 mL of methanol added to 99 mL of tap water was prepared as negative control and Bi-one (1000 mg/L) constituted a positive control. In each test solution, 25 larvae of each mosquito species were separately transferred and larval mortality was recorded after 24 h post-treatment. As results, the three plant seed extracts applied at 1000 mg/L caused for at least 79% mortality of each mosquito species larvae assessed. The seed extract of P. americana (LC50 of 98.31, 129.24 and 136.26 mg/L, respectively against An. gambiae, Ae. aegypti and Cx. quiquefasciatus larvae) was the most potent followed by D. edulis (LC50 of 176.87 mg/L for An. gambiae, 198.68 mg/L for Ae. aegypti and 201.70 mg/L for Cx. quinquefasciatus) and M. indica (LC50 of 258.98 mg/L for An. gambiae, 297.35 mg/L for Ae. aegypti and 435.45 mg/L for Cx. quinquefasciatus). Globally, all the seed extracts were more toxic against An. gambiae larvae compared to other mosquito species and need further exploration for the development of a new botanical larvicide to reduce mosquito densities.

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