Insecticidal activity of marine toad rhinella marina (L.) skin secretions against dengue mosquito Aedes aegypti (L.) (Diptera: Culicidae)

Issue Date

10-2017

Abstract

The insecticidal activity of skin secretions of the marine toad Rhinella marina (L.) was assayed against the dengue mosquito Aedes aegypti (L.). Ether (EF) and aqueous fractions (AF) were prepared through solvent fractionation. Ovicidal and larvicidal activities were determined against A. aegypti. Growth inhibition and oviposition deterrent assays were also done. Distilled water (negative control) and black pepper ethanolic extract at 14 ppm (ovicidal) and 3.97 ppm (larvicidal) were included for comparison. The EF had significantly higher 24-h ovicidal toxicity (LC50 = 22.32 ± 1.98 ppm) and larvicidal toxicity (LC50 = 3.79 ± 0.20 ppm) than the AF with LC50 eggs of 230.28 ± 29.36 ppm) and AF with LC 50 larvae of 9.06 ppm. The higher amount of bufadienolides in the EF of the skin secretions explains the ovicidal and larvididal activity against A. aegypti. Treated larvae produced abnormalities which include ruptured abdomen, damaged exoskeleton, disintegrated internal organ, and in the subsequent adult, enlarged abdomen and extended wing span. Meanwhile, oviposition deterrent activity was 100% for AF and 79% for EF. These findings suggest that the skin secretions of R.marina can be a potent source of insecticidal bioactive compounds.

Source or Periodical Title

The Philippine Entomologist

ISSN

0048-3753

Volume

31

Issue

2

Page

176-177

Document Type

Article

Frequency

semi-annually

Language

English

En – AGROVOC descriptors

AEDES AEGYPTI; TOADS; AMPHIBIANS; AQUATIC ANIMALS; ETHERS; INSECTICIDAL PROPERTIES; LARVICIDAL PROPERTIES; OVICIDAL PROPERTIES; INSECT CONTROL; BIOLOGICAL CONTROL AGENTS

This document is currently not available here.

Share

COinS