Journal of Nematology (2004) 36, p. 344 (Saeb et al.)

Amr T.M. Saeb and Parwinder S. Grewal (2004)
Noval molecular markers for the identification of the species of entomopathogenic nematode Heterorhabditis
Journal of Nematology 36 (3), 344-344
paper presented at the Society of Nematologists 43rd Annual Meeting, Estes Park, Colorado 7-11 August 2004
Abstract: Entomopathogenic nematodes have tremendous potential for the control of many insect pests. However, identification and differentiation between the species of Heterorhabditis is a very complicated task. This study aims to investigate potential use of nova molecular markers including the heat shock protein 70 gene(s), major sperm protein gene(s) and topoisomerase gene to differentiate between the species of Heterorhabditis. For the hsp70 gene family, four sets of primers were designed based on the free-living nematode Caenorhabditis elegans genomic sequences. One primer set targeted one exon area while the other three targeted the intron areas. The genomic DNA isolated from all 6 known Heterorhabditis species was subjected to polymerase chain reaction (PCR) using the primer sets. The amplified intron regions exhibited a distinct and reproducible pattern that characterizes different nematode species. The exon primer set was found to be specific for the species H. megidis for both the US and the European isolates. This exon amplified a product with a molecular weight of 307 bp. DNA Sequencing data showed the amplification product is a pseudogene, phi hsp70. Both msp gene(s) and topoisomerase genes also showed distinct and reproducible patterns that characterized different Heterorhabditis species. This is the first study to use hsp70 gene family and topoisomerase gene as a target to differentiate between the entomopathogenic nematode species. The results of this study will facilitate rapid identification of the nematode species with simple PCR reactions and eliminate the need of inclusion of previously characterized nematode species in each test.
Database assignments for author(s): Parwinder S. Grewal

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
identification/taxonomy
molecular biology - genes

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Heterorhabditis megidis/Photorhabdus temperata (entomopathogen)
Heterorhabditis (genus - entomopathogens)