Morphometrics and Molecular Characterization of New Isolate of Entomopathogenic Nematode, Heterorhabditis Bacteriophora Poinar, 1976 (nematoda, Rhabditida) from the North of Iran

For the first time during the survey of entomopathogenic nematodes in north of Iran, a geographical isolates of Heterorhabditis recovered from soil using Galleria baiting technique. Based on morphological and molecular characterization this isolates was identified as Heterorhabditis bacteriophora NIR1. Morphometric and morphological comparisons of the new isolate with type species and other described isolates from different areas showed that H. bacteriophora NIR1 is morphologically similar to others but differ from type species in the following cases. For infective juvenile, means of body length (582 vs 570 μm), distance from anterior end to nerve ring (86 vs 83 μm) and esophagus length (121 vs 125 μm) and for male, means of body length (910 vs 820 μm), maximum body width (60 vs 43 μm), anal body width (27 vs 23 μm), esophagus length (114 vs 103 μm), distance from anterior end to excretory pore (155 vs 121 μm) and spicule length (42 vs 40 μm) were different from type isolate. Molecular studies of rDNA ITS regions showed that the Iranian isolate is closely related to the other described isolates of H. bacteriophora from other area. Sequence length of amplified region of ITS-rDNA of NIR1 isolate (819 base pairs) is the same as in type species. Intraspecific relationships among isolates of H. bacteriophora showed that geographic distribution is associated with the genetic and morphologic differences.