Molecular systematics and phylogenetic reconstruction of Steinernema and Heterorhabditis .

Entomopathogenic nematodes (EPNs) belonging to the genera Heterorhabditis and Steinernema possess the attribute of potential biological insecticides and are therefore attractive from a commercial viewpoint. These nematodes, in general, are relatively conserved in gross morphology such as microscopic sizes or morphological similarity, thus making the task of identification difficult for taxonomists. Molecular characterization of EPNs has important implications for their proper classification, biodiversity studies, population genetics, ecology and selection of the appropriate species and/or strains in biological control programmes. This chaper discusses different molecular techniques for entomopathogenic nematode identification. These include routine molecular methods (such as polymerase chain reaction (PCR), internal transcribed spacer-restriction fragment length polymorphism, random amplified polymorphic DNA and amplified fragment length polymorphism), DNA barcoding, quantitative PCR, sequencing technologies and phylogenesis.