Open AccessCombined effect of local isolate Spodoptera littoralis nucleopolyhedrosis virus and Bacillus thuringiensis on Culex pipiens L. larvae (Culicidae: Diptera)
Author(s) -
Dalia Mahmoud,
Marah M. Abd El-Bar,
Magda H. Abdul Aziz Radi
Publication year - 2012
Publication title -
journal of basic and applied zoology /journal of basic and applied zoology
Language(s) - English
Resource type - Journals
eISSN - 2090-9896
pISSN - 2090-990X
DOI - 10.1016/j.jobaz.2012.10.007
Subject(s) - culex pipiens , spodoptera littoralis , bruton's tyrosine kinase , bacillus thuringiensis , spore , biology , bioassay , instar , noctuidae , larva , spodoptera litura , microbiology and biotechnology , botany , ecology , bacteria , receptor , biochemistry , genetics , tyrosine kinase
A local isolate of Spodoptera littoralis nucleopolyhedrosis virus (SlNPV) showed pathogenicity against Culex pipiens larvae, its long incubation period was broken using a combination between SlNPV and Bacillus thuringiensis subsp. kurstaki (Btk). Laboratory bioassay tests revealed that Culex pipiens 3rd larval instars were susceptible to the applied combination. Data revealed that the addition of Btk generally increased the toxic effect of SlNPV since LC50 decreased from 1.3×103PIB/ml (for SlNPV alone) to 3.6×102 mixed polyhedra and spores/ml (SlNPV-Btk combination), indicating a synergistic ratio of 3.6. LC95 was surprisingly 137-folds dropped as well. The addition of SlNPV generally increased the toxic effect of Btk at a low concentration, where the LC50 outstandingly decreased from 2.5×105spores/ml (for Btk) to 3.6×102 mixed polyhedra and spores/ml (for SlNPV-Btk combination), indicating a synergistic ratio of 6.9×102