MOLECULAR COMPARISONS OF ENTOMOPATHOGENIC NEMATODES USING RANDOMLY AMPLIFIED POLYMORPHIC DNA (RAPD) MARKERS

The two entomopathogenic nematode genera Heterorhabditis and Steinerne ma were examined for genetic relatedness by random amplified polymorph ic DNA (RAPD) markers. Species of these genera have great potential fo r biological control of insect pests, and rapid and accurate identific ation of the many isolates of these nematodes is important for their i mplementation. Eighty ten-mer random primers were screened for use in determining genetic variability among isolates of Heterorhabditis bact eriophora H. megidis, Steinernema glaseri, S. carpocapsae, and S. felt iae. A similarity of 0-6 % was observed between the members of differe nt genera, and less than 20 % similarity was observed among congeneric species. Genetic analysis using seven primers of different Heterorhab ditis isolates from various parts of the world showed 24-96 % similari ty. These results agreed with other reports which showed many genetic differences among isolates. RAPD analysis described here can be used f or the assessment of genetic variability among species and isolates of entomopathogenic nematodes.