A survey showed that species of Burkholderia were frequently associated with the roots of sugarcane. Based on amplified ribosomal DNA restriction analysis the isolates of these bacteria belonged to Burkholderia groups A,B,C,F and G. Data collected from field trials revealed a succession of species during the growth of the crop. Strains belonging to the B. cepacia complex were dominant during the early stages of growth but, in time, were replaced by isolates of the B. tropicalis and B. caribensis groups. In a series of in vitro bioassays it was found that a large proportion of the Burkholderia isolates tested paralysed juveniles of a root-knot nematode, Meloidogyne sp.