The Fusarium oxysporum F. sp. Coffeae-Meloidogyne incognita Complex in 'Bourbon' Coffee

The interaction of Fusarium oxysporum f. sp. coffeae with Meloidogyne incognita on Coffea arabica was studied in the greenhouse. Coffee seedlings were either not inoculated, inoculated with the fungus alone, the fungus and the nematode simultaneously, or the fungus 2 or 4 weeks after the nematode. Chlorosis, root necrosis, wilting, and stunting were greater in plants inoculated with the fungus 4 weeks after the nematode. Similar but less severe symptoms were observed in plants to which the fungus was added 2 weeks after the nematode. Significant differences among treatments were found in height and dry weight of roots and shoots. Histological studies of root sections revealed giant cell development and hyphal penetration of giant cells, xylem vessels, and the female nematode.