International Journal of Nematology (2007) 17, 116-123

Mahfouz M.M. Abd-Elgawad and Khuong B. Nguyen (2007)
Isolation, identification and environmental tolerance of new heterorhabditid populations from Egypt
International Journal of Nematology 17 (2), 116-123
Abstract: Four Egyptian strains of entomopathogenic nematodes, EG,, EG2, EG3 and EG, were recently isolated from Behera, Gharbia, Kaliobia and El-Menia Governorates of Egypt. The air temperature is high (35-42°C) in these areas in summer. Morphological and molecular studies showed that these strains are Heterorhabditis bacteriophora. In a heat tolerance assay using the four isolates as well as H. bacteriophora HP88, the strain EG, was the most tolerant (P 0.05), with about 30% of its infective juveniles (IJs) remaining alive after 5 hours exposure at 37°C. In a desiccation assay, their exposure to low relative humidity (25±0.5°C, 40-57% 12H) for three hours accounted for 91, 67; 49, 61 and 94% death of the infective juveniles of H. bacteriophora strains EG1, EG2, EG3 , EG, and HP88, respectively. Significantly (P 0.05) higher tolerance to desiccation conditions was exhibited with EG2, EG3 and EG4 than with EG, and HP88. These results may further stimulate a survey of entomopathogenic nematodes in areas characterized by extreme environmental conditions.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Mahfouz M.M. Abd-Elgawad

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Heterorhabditis bacteriophora/Photorhabdus (entomopathogen)			Egypt