Mosquito autogeny in Aedes caspius (Diptera: Culicidae): alterations of larval nourishments reservation upon bacterial infection
, Ahmed, A. M. . 2013
The present study recorded mosquito autogeny for the first time amongst Aedes
caspius species in the Eastern region of Saudi Arabia. Laboratory rearing showed an
obligatory autogenous species of Ae. caspius since it foregoes blood feeding during its
first ovarian cycle, even in the presence of the hosts (CD mouse), but produces its second
egg batch only if ingested a blood meal. Both morphological and molecular identification
confirmed that both autogenous and anautogenous strains belong to the same species of
Ae. caspius. Data from biochemical analysis showed significant 2, 1.6, and 1.4 folds higher
total carbohydrates, proteins, and lipids reserves respectively in the fourth larval instar of
the autogenous strain compared to that of the anautogenous ones. In addition, exposing the
fourth larval instars of autogenous strain to the infection stress by the mosquito larvicidal
bacterium, Bacillus thuringiensis var kurstaki has significantly reduced total carbohydrates,
proteins and lipids reserves by 29%, 35%, and 46%, respectively, at 12 h postinfection
compared to those of uninfected ones. These reductions in nourishment reserves weremore
pronounced at 24 h postinfection in the case of proteins and lipids, but not carbohydrates.
These results may indicate that bacterial infection is a health stress that significantly
reduced nourishments reservation, which may interrupt the success of adult autogeny.
However, the impact of infection-induced decline in larval nourishments reservation on
successful adult autogeny is still to be investigated.
