Sterile carrot disks have been used successfully for monoxenic culture of root lesion nematodes such as Pratylenchus brachyurus (Moody et al., 1973) and P. vulnus (Townson & Lear, 1982), and excised maize roots have been used to rear P. penetrans (Tiner, 1960) and P. zeae (Jordaan & De Waele, 1988). Recent reports have indicated that P. sudanensis is causing damage to yams (Dioscorea spp.) in Uganda (Mudiope, 1999;Coyne et al., 2003). Information on the biology and epidemiology of P. sudanensis is very limited. It has been associated with over 20 plant species in Sudan, however, where it is viewed as an economically damaging pest of cotton (Saadabi, 1985). Other favourable hosts included sorghum, pigeon pea and lubia bean. Wheat and groundnut were viewed as non-hosts. In order to investigate further the biology of this nematode, a readily available source of nematode cultures would be needed. Therefore, sterile carrot disk and excised maize root methods were assessed for their ability to support mass culture of P. sudanensis. Materials and methodsThree separate geographical populations of P. sudanensis from Rakai, Masaka and Jinja Districts, Uganda, were used in the study, all originating from yam roots and tubers. The districts all border Lake Victoria, are at similar altitudes (approx 1500 m above sea level) and are in relatively close proximity to each other. For each isolate,