Abstract:
Abstract
Background: The midgut microbiota of mosquitoes maintain basal immune activity and immune priming. In recent
years, scientists have focused on the use of microbial communities for vector control interventions. In the present
study, the midgut bacteria of larvae and adults of Aedes aegypti and Ae. albopictus were assessed using both fieldcollected
and laboratory-reared mosquitoes from Sri Lanka.
Methods: Adults and larvae of Ae. aegypti and Ae. albopictus were collected from three selected areas in Gampaha
Medical Officer of Health area, Gampaha District, Western Province, Sri Lanka. Bacterial colonies isolated from mosquito
midgut dissections were identified by PCR amplification and sequencing of partial 16S rRNA gene fragments.
Results: Adults and larvae of Ae. aegypti and Ae. albopictus harbored 25 bacterial species. Bacillus endophyticus and
Pantoea dispersa were found more frequently in field-collected Ae. aegypti and Ae. albopictus adults, respectively.
The midgut bacteria of Ae. aegypti and Ae. albopictus adults (X2 = 556.167, df = 72, P < 0.001) and larvae (X2 = 633.11,
df = 66, P < 0.001) were significantly different. There was a significant difference among the bacterial communities
between field-collected adults (X2 = 48.974, df = 10, P < 0.001) and larvae (X2 = 84.981, df = 10, P < 0.001). Lysinibacillus
sphaericus was a common species in adults and larvae of laboratory-reared Ae. aegypti. Only P. dispersa occurred in the
field-collected adults of Ae. aegypti and Ae. albopictus. Species belonging to genera Terribacillus, Lysinibacillus, Agromyces
and Kocuria were recorded from Aedes mosquitoes, in accordance with previously reported results.
Conclusions: This study generated a comprehensive database on the culturable bacterial community found in the
midgut of field-collected (Ae. aegypti and Ae. albopictus) and laboratory-reared (Ae. aegypti) mosquito larvae and adults
from Sri Lanka. Data confirm that the midgut bacterial
