FUNGAL-DERIVED OLFACTORY CUES AS OVIPOSITION ATTRACTANTS FOR MOSQUITOES: TOWARD A NOVEL LURE-AND-KILL STRATEGY

INTRODUCTION. The global threat posed by mosquitoes is intensifying due to climate change and increased human mobility, enabling these vectors to expand into new geographic regions. Mosquitoes act as vectors of numerous pathogens, transmitting protozoans such as Plasmodium spp. (the causative agents of malaria) and helminths including filarial worms. They also pose zoonotic risks, exemplified by Dirofilaria immitis, which affects both animals and humans. Moreover, mosquito-borne arboviruses, such as Dengue, Zika, West Nile, and Chikungunya, represent a growing public health challenge. Pathogen transmission is driven by the hematophagous behavior of female mosquitoes, which acquire infectious agents during blood feeding and subsequently transmit them to new hosts. Despite multidisciplinary control efforts, including vaccination, pharmacological interventions, and genetic strategies, the global burden of mosquito-borne diseases remains substantial. This has stimulated interest in innovative approaches such as “lure-and-kill” strategies, which exploit attractants to target specific mosquito populations. MATERIALS AND METHODS. Recent studies have highlighted the role of microorganisms as potential sources of attractant cues. In this study, we evaluated the oviposition attraction potential of four fungal strains, Wickerhamomyces anomalus, Barnettozyma californica, Metschnikowia pulcherrima, and Rhodotorula paludigena, previously isolated from mosquito larvae collected in natural breeding sites. Oviposition-site selection bioassays were conducted using gravid Aedes spp. females housed in BugDorm cages containing two oviposition substrates: one supplemented with fungal cultures (1 × 10⁵ cells/ mL) and a control containing only YPD medium, positioned at opposite corners. To further elucidate the mechanisms underlying attraction, electroantennography (EAG) and dual-choice Y-tube olfactometry were employed. EAG was used to assess peripheral olfactory sensitivity and enable high-throughput screening of volatile organic compounds (VOCs), while olfactometry assays quantified behavioral responses to specific odor cues. RESULTS AND CONCLUSION. Results demonstrated that all tested fungal strains exhibited attractant potential, with slightly higher egg deposition observed in fungus-treated sites compared with controls. Behavioral responses to odor stimuli were found to be influenced by multiple biotic and abiotic factors. Accordingly, variables such as circadian rhythm, time of day, mosquito age, activity level, mating status, and feeding condition are currently being investigated to refine and optimize experimental conditions. These findings support the role of fungal-derived volatile cues as effective oviposition attractants for Aedes spp., highlighting their potential application in environmentally sustainable lure-and-kill strategies. Further characterization of the underlying chemical signals and optimization of behavioral parameters will be critical for translating