GENETIC-VARIATION IN TROPICAL MELOIDOGYNE SPP AS SHOWN BY RAPDS

Random Amplified Polymorphic DNA (RAPD) fingerprinting was used to ass ess within and between species variability in tropical Meloidogyne spp . Reproducibility of the technique was assessed. M. arenaria showed th e most within species variability; species were distinguished with onl y a few primers though some primers group some of the M. arenaria line s more closely with M. javanica than with other M. arenaris lines. Thr ee virulent lines of M. arenaria were differentiated from both avirule nt of this species and the other lines of M. javanica, M. incognita, M . mayaguensis and M. hapla. Primers contributed more to variability in the data than genotypes. Comparison of RAPD with RFLP (restriction fr agment length polymorphism) data showed similar levels of interspecifi c difference between species variation but greater within species vari ation with the RAPDs.