Year 2017, Volume 63 Issue 4 (15.12.2017)
Year : | 2017 |
Volume : | 63 |
Issue : | 4 (15.12.2017) |
Authors : | Farida BENZINA, Hakima OULEBSIR-MOHANDKACI, Messaouda BELAID, Hamama IRNATENE, Sonia MAMMERI |
Title : | ISOLATION OF ENTOMOPATHOGENIC BACTERIA FROM LARVAE OF A LEPIDOPTERAN SPECIE; GALLERIA MELLONELLA AND STUDY OF THEIR INSECTICIDAL EFFECT |
Abstract : | Few years ago, considerable progress has been made to explain the disappearance of bee colonies, including correct identification of pests involved and the search for more effective and healthy alternatives to protect them. Indeed, our work is based on the isolation, characterization and identification of entomopathogenic bacterial strains of the genus Bacillus from larvae of wax moth Galleria mellonela reared in the laboratory, with a preliminary study of the use of these entomopathogenic bacteria on the larvae (L5) of G. mellonella under controlled conditions. In fact, 9 bacterial strains of the genus Bacillus have been isolated. They are spore forming bacteria, Gram, catalase and oxidase positive and present variable responses to the gelatinase test, lecitinase, caseinase, culture in anaerobiosis and growth at different temperatures (45 ° C., 55 ° C., 65 ° C.). From our study, we also find that the strain S4, probably identified as Bacillus thuringiensis, has a better effect on the larvae of Galleria mellonella. It caused very remarkable symptoms and mortality rates that vary depending on the strain and bacterial concentration tested and the mode of application. Injection of strain S4 for individuals resulted mortality of 83.33%, 75% and 50%, respectively, after treatment with high, medium and low concentration after only 3 days. The comparative examination of the hemolymph test results shows that the injection of the bacteria into the larvae resulted in a significant increase in hemolymph protein and carbohydrate content as compared to controls |
For citation : | Benzina F., Oulebsir-Mohandkaci H., Belaid M., Irnatene H., Mammeri S. (2017): Isolation of entomopathogenic bacteria from larvae of a Lepidopteran specie; Galleria mellonella and study of their insecticidal effect. Agriculture and Forestry, 63 (4): 59-68. DOI:10.17707/AgricultForest.63.4.06 |
Keywords : | Galleria mellonella, Bacillus, isolation, mortality, haemolymph. |
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