After tomatoes I usually use a nemacidal cover crop like sunn hemp, sudangrass, French marigolds, or if you wait until cooler weather, cereal rye.

I never plant a vegetable directly after tomatoes, but if I did I would check and see if there was any nematode damage on the roots. If yes, I would plant mustard or maybe onions, because they are both resistant. If no, I might try peas because they're a legume. But I wouldn't plant a vegetable after tomatoes unless I felt I had to.

Bill

Thanks. I had heard about the marigold cover crop before. I will check the roots for nematodes too.