Reproduction on cotton (cultivars Deltapine 20, LA 887, and Auburn 56) and soybean (Forrest, Kirby, and Davis) varies significantly among populations of reniform nematode from Louisiana and between populations from Louisiana and Mississippi. Greenhouse experiments were of 60 and 90 day durations and each was repeated at least once. Microplot experiments were full season in duration and conducted during 1992. Pathogenicity of three reniform populations (Evangeline, Opelousas, and Avoyelles) on Deltapine 20 cotton and Davis coybean were compared in a 62 day duration greenhouse experiment. All populations caused significant reductions in weights of cotton and soybean shoot and root systems with the Opelousas population being the most damaging. There were also significant differences in the viability of eggs collected from females from four populations. Egg hatch was evaluated by placing freshly collected eggs in either water or soil and counting numbers of juveniles which emerged from eggs over a period of ten days.