Role of Pratylenchus sudanensis, A Root-Lesion Nematode in the Syndrome of Cotton Wilt in Gezira Area of Sudan

Interaction between root-lesion nematode Pratylenchus sudanensis and the fungus Fusarium oxysporum f.sp. vasinfectum on cotton was studied under controlled glass-house conditions. The growth of the plants was reduced significantly when plants were inoculated with both pathogens after sequential and simultaneous treatment. Reduction in length and weight of shoot and root was maximum in simultaneous inoculations with Barakat cotton cultivar. The rate of P. sudanensis multiplication was adversely affected when fungus was inoculated earlier than nematode. Although the three tested Gossypium barbadense cotton cultivars are differed in their susceptibility to nematode attack, they invariably showed faster infection and the number of wilted plants was greater when the fungal infection occurred in the presence of the nematode. Such differences were most apparent with fungal isolates obtained from Gezira Research Station Farm on Barakat cultivar as compared to GS (81) and Giza (70) cotton cultivars.