| Abstrakt: |
Background: Integrated pest management is one of the ways to solve the problems of increased outbreaks of pests induced by the effects of climate change. Therefore, the present investigation was carried out to study the integrated effect of entomopathogenic fungus, Metarhizium anisopliaeand gamma radiation to control 5th instar larvae the black cut worm, Agrotis ipsilon(Hufnagel) (Lepidoptera: Noctuidae), under laboratory condition. The leaf dipping technique was used to test the pathogenicity of different concentrations of the fungus against normal and F1 (resulted from irradiated male parent pupae with 100 Gy) larvae. As well as, the changes in the haemocytes were studied using LC50of M. anisopliaeof both treatment (unirradiated and F1 larvae). Results: The results showed that larval mortality percentage was both M. anisopliaevirulent and time dependent. Furthermore, F1 larvae were more susceptible to M. anisopliaewhere 100% mortality was recorded after 3 days of M. anisopliaetreatment at 8 × 105spores/ml concentration. While mortality of normal (unirradiated) larvae reached 40% at the same time and concentration. The haematological examination of larvae revealed significant reduces in total haemocyte counts, differential percentage and increase in morphological malformation of the haemocytes which was pronounced by F1 + M. anisopliaeLC50. Conclusions: According to the obtained results, the gamma irradiation increased the pathogenicity of the fungus against the 5th instar A. ipsilonlarvae. So, the combination between the two control tools may provide a satisfactory integrated control program after further field trials. |
Full text from SpringerLink