Enzyme phenotypes of Meloidogyne spp. populations

Enzyme phenotypes, specifically esterases (EST), malate dehydrogenase (MDH) , superoxide dismutase (SOD) and glutamate-oxaloacetate transaminase (GOT) were used to characterise different species of Meloidogyne, mostly from Bra zil and from some American countries. Esterase activity was highly polymorp hic and was the most useful in the identification of the different species. Using this enzyme it is possible to characterise and identify the four maj or species: M. javanica, M. incognita, M. arenaria and M. hapla from a larg e collection of 111 populations of Meloidogyne.,le spp. Another seven less common species (M. coffeicola, M. paranensis, M. konaensis, M. exigua, M, g raminicola, M. oryzae, M. mayaguensis), with only one or a few populations of each, were studied and exhibited species-specific EST phenotypes. The tw o enzymes (EST and MDH) differentiated M. graminicola and M. oryzae. It was possible to detect atypical (unidentified) phenotypes: three fr om Brazil, one from the USA and another from Chile. The minor bands of esterase profi ts provided information to detect intraspecific variability among some popu lations of M, incognita and six populations of M. exigua. Profiles of MDH p ermitted separation of two isolates of M. javanica a from Brazil.