In an experiment investigating the influence of M. graminicola on rice yield, M. graminicola caused as significant yield reduction in Azucena but not in Bala indicating that this variety is tolerant. The influence of abiotic (nitrogen and water) and biotic (vesicular arbuscular mycorrhiza - VAM) factors on the nematode/rice interaction were also studied. Nitrogen stress affected Azucena plants but not Bala. Drought did not influence susceptibility of either variety but caused a significant reduction in root weight which was greater when nematodes were present in both rice varieties.