The effects of fertilizer application on the efficacy of the 10G formulation of fenamiphos (13.5 kg a.i./ha broadcast) against phytoparasitic nematodes in 'Tifgreen' bermudagrass (Cynadon dactylon x C. transvaalensis) were examined at three locations on Margate fine sand with different soil-amendment histories. The soils were unamended, colloidal phosphate, or composted-sewage amended 2 yr prior prior to the study. Turfgrass quality ratios at 28 and 56 days after nematicide application showed a significant (P = 0.05) nematicide response at the two locations without sewage amendment. A significant fertilizer effect (P = 0.01) was observed as early as 7 days following fertilizer application and lasted at least 35 days at the two amended sites. Root biomass increased significantly (P = 0.01) in nematicide treated plots 56 days following application at the unamended location. There were significant (P = 0.05) decreases due to fenamiphos in the Pm/Pi ratios for Belonolaimus longicaudatus
