الفهرس 
Classification of Culex mosquitoOnly 14 pages are availabe for public view
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Abstract
In this work, 62 bacterial and actinobacterial isolates were
isolated from different soil samples and screened for their
larvicidal activities against the 3rd instar Culex pipiens larvae. Two
potent isolates that showed high mortality rate were identified by
16S rRNA gene sequencing as Bacillus subtilis (MH370499) and
Streptomyces griseoruber (MH370498). Optimizing the
environmental and nutritional conditions increased the corrected
mortality percentage of B. subtilis from 72.9% to 100% and S.
griseoruber from 69% to be 100%. LC50 and LC90 of B. subtilis
were 11.37% and 24.64% respectively after 48 h. produced by B.
after 48 h, while for S. griseoruber were 4.62% and 11.52%.
The best solvent for active substance from B. subtilis
extraction was ethyl acetate, while for S. griseoruber was hexane.
The GC-MS analysis of S. griseoruber detected the presence of
antilarval compounds ambrosin and triacontane. In addition,
surfactin and chitinase production (by B. subtilis and S. griseoruber
respectively) were the major substances responsible for larvicidal
activities. SDS analysis revealed the presence of different protein
bands for both isolates.
Key words: Control, Culex, Streptomyces, Bacillus, mosquito.