Journal Details


Volume Number:  3
Jurnal Name:  Efflatounia

Authors: 
               Alia Zayed
               Muhammad Shamseldean
               Khaled M. Abd-El Aleem
               Yasmin A. Fergany

Title:
INTERACTIONS BETWEEN BEAUVERIA BASSIANA AND THE ENTOMOPATHOGENIC NEMATODES HETERORHABDITIS BACTERIOPHORA AND STEINERNEMA SP. I: IN VIVO EFFECTS ON HOST PREFERENCE OF THE NEMATODE AND ON PATHOGEN PROGENY PRODUCTION IN THE GREATER WAX MOTH GALLERIA MELLONELLA L.

Keywords: 
Entomopathogenic fungus Beauveria bassiana , entomopathogenic nematodes, Heterorhabditis bacteriophora , Steinernema sp. , interactions, antagonism, synergism, host preference, progeny production.

Abstract:
The interaction between indigenous isolates of the entomopathogenic fungus, Beauveria bassiana (Bb2) and the entomopathogenic nematodes, Heterorhabditis bacteriophora (EBN10K) and Steinernema sp. (EGBS) was investigated in this study. Both pathogens were tested singly, simultaneously and in different sequential combinations against the last instar larvae of the greater wax moth, Galleria mellonella L. Two concentrations, 500 and 1500 infective juveniles (IJs)/ml, of both nematodes were used in this study. The simultaneous treatments with both pathogens, except for using 1500 IJs/ml of H. bacteriophora , resulted in a synergistic effect on the larval mortalities compared to the single infection of each pathogen. The initial exposure to B. bassiana exhibited an antagonistic effect on both nematodes, particularly Steinernema sp. which was adversely affected. There was no evidence that both pathogens could reproduce in the same infected cadaver. Infective juvenile production of H. bacteriophora increased gradually with the increase of initial fungal exposure period from 1 to 3 days, at both low and high IJs concentrations. Mutual incompatibility between B. bassiana and the high concentration of H. bacteriophora was observed through the progeny production when the fungus was initially applied 5 days prior to the nematode. Steinernema sp. failed to reproduce in the initially fungus-infected larvae at low nematode concentration where the fungus was the dominant pathogen in the cadavers. However with the application of high nematode concentration, Steinernema sp. reproduced in the host but at a lower rate rather than by H. bacteriophora . The results indicated that the increase of IJs concentration has an adverse effect on the production of the fungus in G. mellonella cadavers.

Paper Pdf. File:
Paper Pdf. File
http://www.efflatounia.com/files/03-03.pdf