P-8 - The attractant effects of three cyanobacterial taxa on Aedes aegypti oviposition.

Abstract: This research aims to identify effective, environmentally friendly attractants that can be further developed to control Aedes aegypti populations by targeting oviposition behavior and potentially reducing the spread of arboviruses. Ae. aegypti mosquitoes are the primary vectors of the dengue viruses. They utilize various chemosensory cues to select where they lay their eggs. Previous research showed that periphyton, the community of organisms defined as the bacteria, algae, and fungi living on surfaces beneath the water along with organic and inorganic detritus, is a strong attractant for gravid females, with cyanobacteria identified as key taxa. This study investigated whether cyanobacteria played a role in attracting Ae. aegypti mosquitoes for oviposition. To explore this, we tested whether three cyanobacterial strains- Anabaena spp, Oscillatoria spp, and Spirulina major- commonly found in larval environments and larval gut content of Ae. aegypti, influenced oviposition preferences. Using black ovi-cups, we conducted dual-choice assays of gravid Ae. aegypti mosquitoes, comparing two concentrations of each cyanobacterium. Egg papers were collected 24 hours post-release, and preference was determined based on egg count, followed by statistical analysis using analysis of variance in RStudio. Preliminary findings suggested that higher concentrations of the three tested cyanobacteria strains were more attractive for oviposition. These results may indicate that cyanobacteria in periphyton provide specific chemical or nutritional cues that attract female mosquitoes. Future experiments will focus on testing combinations of cyanobacteria strains to determine if they enhance attraction, comparing results to water and periphyton controls.