Fragments containing the internal transcribed spacer (ITS) ribosomal rDNA were amplified from Meloidogyne incognita, M. javanica, M. arenaria and M. hapla by polymerase chain reaction (PCR). Only digestion of the ITS region with the enzyme RsaI significantly distinguished M. hapla from other species, while other enzymes, EcoRI and BamHI, were not effective in distinguishing these nematode species. PCR was also done with mitocondrial DNA (mtDNA) markers for species discrimination. The obtained amplification product of 600 bp was digested with HinfI restriction endonuclease allowing discrimination among the four root-knot species. mtDNA was found to be a useful tool for discriminating between the important Meloidogyne species in this study.

Fragments containing the internal transcribed spacer (ITS) ribosomal rDNA were amplified from Meloidogyne incognita, M. javanica, M. arenaria and M. hapla by polymerase chain reaction (PCR). Only digestion of the ITS region with the enzyme RsaI significantly distinguished M. hapla from other species, while other enzymes, EcoRI and BamHI, were not effective in distinguishing these nematode species. PCR was also done with mitocondrial DNA (mtDNA) markers for species discrimination. The obtained amplification product of 600 bp was digested with HinfI restriction endonuclease allowing discrimination among the four root-knot species. mtDNA was found to be a useful tool for discriminating between the important Meloidogyne species in this study.