Effect of selected marine and freshwater microalgae on development and survival of the mosquito Aedes aegypti

Abstract

We isolated and identified strains of marine and freshwater planktonic and benthic microalgae from the vicinity of Indian River County, Florida (&27.5°N, 80.34°W), cultivated them in batch culture, and examined their allelopathic activity against mosquito larvae. Additional algal material was obtained from Syracuse University and the University of Texas-Austin Algal Culture Collection. Mosquito larvae (Aedes aegypti (L.)) from colonies maintained at the Florida Medical Entomology Laboratory were challenged with the microalgae using log-growth phase and senescent-phase cultures. Appropriate controls (no algae) were used for each treatment. There were no significant differences in development time between treatments across all trials and a few significant treatment effects on development times, mortality, or mosquito size in the individual trials; however, there was a tendency for treatments with senescent microalgae to develop faster than controls with no algae. Effects consistent with algal toxicity included the two trials with Microcystis aeruginosa, where the larvae exposed to the strain-producing microcystin had significantly longer development times than the controls or those grown with the non-microcystin-producing strain, and the trial with the dinoflagellate Akashiwo sanguinea, where larvae exposed to this species had significantly higher mortality than the controls. No consistent patterns or differences between experimental and control treatments in the value of k 0 , an estimate of the population finite rate of increase, were discernible from the data.

Pesticide‐mediated trophic cascade and an ecological trap for mosquitoes

“…Therefore, it is important to understand how aquatic community assembly is altered by changes in response to contaminants and how behavioral shifts in response to pesticide treatments could alter the ecological context. Green algae are likely to affect mosquito larval survival, although so far this has only been demonstrated under laboratory conditions (Marten 2007, Rey et al 2009). Our study suggests that this effect may be important in natural systems, in which algal species composition has been indirectly affected by pesticides.…”

North American Wetlands and Mosquito Control

“…There are several biological agents that have been shown to cause mortality in mosquitoes including algae [141,142], oomycetes [143,144], bacteria ( Bti , Ls , and recombinant bacteria) [145,146], microsporidian and gregarine parasites [147,148], pathogenic viruses [145], nematodes [149], predatory insects [150,151] including other mosquitoes [152,153], copepods [154,155], fish [156,157] and others. For general reviews of biological control of mosquitoes consult Chapman [158], Floore [159], and Rey [160].…”

Metabolites from freshwater aquatic microalgae and fungi as potential natural pesticides

“…Effects of them could be the toxicity to aquatic stages of mosquitoes, reduction of population by algae's indigestibility or modification of the reproductive cycles (Marten 1986;Rao et al 1999;Ahmad et al 2001;Tuno et al 2006;Marten 2007;Rey et al 2009). The use of microalgal hepato and neurotoxins as mosquito control agents is not recommended for environmental implications.…”