was first described in Florida, USA, in 2004 but has since been reported in California, South Carolina, and Georgia. Our objective was to determine the galling and reproduction differences between two isolates of , Mf3 and MfGNV14, on culinary herbs. A duplicated study was performed where both isolates were inoculated separately to nine culinary herbs (basil, catnip, chicory, dill, fennel, marjoram, parsley, sage, and thyme). Tomato was used as a susceptible reference. Regardless of the isolate, chicory and marjoram had the lowest gall indices (1.85 and 1.00, respectively) and egg mass indices (1.25 and 0.90, respectively). The reproduction rate of Mf3 was greatest under catnip (959 eggs/g fresh root) and thyme (701 eggs/g fresh root), followed by sage (549 eggs/g fresh root) and parsley (501 eggs/g fresh root). Catnip (2,151 eggs/g fresh root) stood out for number of eggs among all tested herbs, followed by tomato (1,153 eggs/g fresh root) and sage (847 eggs/g fresh root) for MfGNV14. Marjoram was a non-host, chicory, fennel, and thyme were poor hosts, and catnip, parsley, and tomato were good hosts to both isolates. Basil, dill, and sage responses were isolate-specific, i.e., resistant to Mf3 but susceptible to MfGNV14.
