Biological control of Culex pipiens by local bacterial isolates

Abstract

Seven soil samples were collected from locally cultivated and contaminated soils from Cairo and El-Qalyubia governorates Shibin El-Qanater, Qalyub (El-Qalyubia) and Teraat Al Ismailiah (Al Amireyah Ash Shamaleyah and Qesm Than Shubra Al Kheimah, Cairo). A total of 62 different bacterial (46) and actinobacterial (16) isolates were recovered from the soils. All isolates were screened for their larvicidal activities against 3rd instar of Culex pipiens larvae. Only 13% were found to achieve mortality more than 50%. Isolates BAC (bacteria) and SC10 (actinobacteria) showed mortality average 82.9% and 69%, respectively against Cx. pipiens larvae. They were identified by 16S rRNA gene sequencing to Bacillus subtilis (MH370499) and Streptomyces griseoruber (MH370498). The growth conditions of the isolates were optimized by varying different physical and chemical