Host plant resistance is the most economic and effective strategy for Fusarium wilt control. To implement steps to develop resistant germplasm to this pathogen, existing commercial Acala, non-Acala Upland (Gossypium hirsutum) and Pima (G. barbadense) varieties, and improved germplasm were subjected to FOV race 1 with root-knot nematodes and race 4 field disease pressures. Variability for FOV races 1 and 4 occurs in both G. hirsutum and G. barbadense cottons. Certain forms of this pathogen can survive for a long time in soils even if the host plant is not present. Host-plant resistance levels from each race (1 and 4) as well as disease expression comparison between the two races data will be presented from evaluated commercial cottons and improved germplasm.