Chemosensory Cues for Mosquito Oviposition Site Selection

Abstract

Gravid mosquitoes use chemosensory (olfactory, gustatory, or both) cues to select oviposi tion sites suitable for their offspring. In nature, these cues originate from plant infusions, microbes, mosquito immature stages, and predators. While attractants and stimulants are cues that could show the availability of food (plant infusions and microbes) and suitable conditions (the presence of conspecifics), repellents and deterrents show the risk of predation, infection with pathogens, or strong competition. Many studies have addressed the question of which substances can act as positive or negative cues in different mosquito species, with sometimes apparently contradicting results. These studies often differ in species, substance concentration, and other experimental details, making it difficult to compare the results. In this review, we compiled the available information for a wide range of species and substances, with particular attention to cues originating from larval food, immature stages, predators, and to syn thetic compounds. We note that the effect of many substances differs between species, and that many substances have been tested in few species only, revealing that the information is scattered across species, substances, and experimental conditions.

Rice volatiles lure gravid malaria mosquitoes, Anopheles arabiensis

“…Mosquitoes use volatiles originating from plants as attractants and stimulants for oviposition40. While gravid anopheline mosquitoes display preferences for volatiles associated with living plants41 and microbes associated with their larval habitats1920, culicines prefer those associated with the microbial fermentation of plant tissues2542.…”

Dengue virus infection changes Aedes aegypti oviposition olfactory preferences

“…Semiochemical preferences vary with the mosquito species and concentration, (reviewed by Afify et al . 29 ), but also with experimental assay conditions, including rearing methods, or the presence of background odours 30 .…”

A(maize)ing attraction: gravid Anopheles arabiensis are attracted and oviposit in response to maize pollen odours

“…Gravid females should select enemy-free and nutrient-rich habitats for their offspring, as mosquito aquatic stages are restricted in mobility within the maternally selected habitats [2, 3]. Breeding habitats with reduced predator [4, 5] and competitor pressures [5, 6], as well as sufficient food availability, are vital for determining mosquito fitness [7], and directly affects vectorial capacity and competence [8–11].…”

“…Breeding habitats with reduced predator [4, 5] and competitor pressures [5, 6], as well as sufficient food availability, are vital for determining mosquito fitness [7], and directly affects vectorial capacity and competence [8–11]. While a number of studies have characterized predator and competitor cues, little is known about how gravid mosquitoes make use of larval nutrient cues to select breeding habitats [3]. Larval mosquito diets have hitherto been shown to contain microorganisms, including algae and bacteria, along with pollen and particulate organic detritus [6, 9, 12–14].…”