Autogenous mosquitoes produce eggs without ingesting blood as adults and rely on their larval nutrition for egg provisioning. Autogeny is genetically determined but the expression of autogeny is affected by poor nutrition or crowding during the larval stage. We report on the effect of larval and adult nutrition on autogenous egg production by Ochlerotatus atropalpus. Ochlerotatus atropalpus is obligatory autogenous during its first egg cycle and is anautogenous during its second cycle. We also report on the effect of larval nutrition on a closely related anautogenous species, Ochlerotatus epactius. Overall, poor larval nutrition results in smaller sized adult females, lower fecundity and smaller levels of nutrient stores (total amount of lipid, glycogen and protein). Nutrient storage by Oc. epactius is not affected by larval nutrition, but meaningful nutrient storage for autogenous Oc. atropalpus is strongly dependent on a high quality larval diet. I next determined the importance of adult nutrition (water vs. sugar) toward autogenous egg production. Regardless of larval and adult nutrition female Oc. atropalpus produce their first egg batch autogenously. However, only those females that experienced a poor larval environment were motivated to blood feed and produce a second egg batch. Although Oc. atropalpus is not a vector during its anautogenous phase, my data support other studies in which medically important mosquito species required multiple blood meals as adults if they were nutritionally stressed as larvae. This scenario only increases the likelihood of vector-borne disease transmission.
Species 1: Diptera Culicidae Ochlerotatus atropalpus
Species 2: Diptera Culicidae Ochlerotatus epactius
Keywords: Autogenous egg production, Larval nutrition
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