DIFFERENTIATION OF BACTERIAL-FEEDING NEMATODES IN SOIL ECOLOGICAL-STUDIES BY MEANS OF ARBITRARILY-PRIMED PCR

Arbitrarily-primed polymerase chain reaction (ap-PCR) was used to diff erentiate closely related bacterial-feeding nematodes of the genera: C aenorhabditis, Acrobeloides, Cephalobus and Zeldia. Average percentage similarity of bands generated by ap-PCR with seven different primers between 14 isolates of Caenorhabditis elegans was > 90%, whereas betwe en C. elegans, C. briggsae and C. remanei similarity was <20%. Based o n intra- and inter-specific similarity between Caenorhabditis isolates , analysis of Acrobeloides, Cephalobus and Zeldia isolates revealed ei ther similar or different genotypes. Distinct genotypes were verified by morphological analyses. In addition, the genotypes obtained from si ngle egg-derived nematode populations were also obtained from ap-PCR a nalysis of single worms. Due to the difficulty of identification of so il nematodes, the ap-PCR offers potential as a rapid and reliable tech nique to assess biodiversity. Ap-PCR will make it feasible, for the fi rst time, to study the ecological interactions of unique nematode geno types in soil habitats.