Article bibliographique

More than one hundred species of nematodes have been reported from upland and paddy rice in many countries (Tab. 1). Their frequency and importance are very variable and, in most cases the existence of a parasitic relationship with rice is probable but has not been demonstrated. Many species of root nematodes have been observed both in dry and irrigaftieldd s but very few species are found in both situations. Several surveys made by the authors in WAefrsitc a have shown that a relatively low number of species are adapted to permanently flooded conditions. When the field is only temporarily flooded, the number of species present is higher and the nematode fauna tends to ressemble that observed in uplandr ice fields, which is composeodf species also common in other crops. Unfortunately, in many papers, the authors fail to indicate with what kind of rice (paddy or upland rice) the parasite was associated. Nematodes attacking roots can be diviidnetdo three categories.