Abstract: The anatomy of eggplant roots as affected by the application of IAA, Agrobacterium tumefaciens and Meloidogyne incognita alone and in combination was studied. IAA and A. tumefaciens, alone and in combination increased the root diameter, cortex thickness, number of cortex layers, stele diameter, number of xylem vessels but decreased the vessel diameter. Inoculation with M. incognita led to the formation of multinucleated giant cells surrounded by deformed xylem elements, hypertrophy of the cortex and hyperplasia of the pericycle. More giant cells with higher dimensions were formed and more eggs/egg mass were produced in plants where IAA, A. tumefaciens alone or in combination was introduced with M. incognita. On the other hand, the presence of IAA, A. tumefaciens or their combination extended the life-span of giant cells, providing long-lasting feeding sites for the nematode. The auxin-mediated role of A. tumefaciens in development and reproduction of M. incognita was discussed.