Characterization of species and races of the genus meloidogyne by DNA restriction enzyme analysis.

Total DNA of three species of Meloidogyne spp., including four subspecific races of M. incognita, were digested separately with EcoR I, Cla III, and Hind III and probed with (3)(2)P-labelled total genomic DNA from M. incognita race 1 in Southern hybridizations. Short exposures of Southern blots after Hind III digestion revealed patterns that were useful for separating the species. Race differences were seen after longer exposures. The DNA fragment patterns obtained were scanned with a laser densitometer and the data were subjected to principal coordinate and cluster analyses. The likelihood of cloning species and race-specific DNA probes is discussed.