Our community garden suffers from attacks from squash bugs and cucumber beetles. Last year I got one cucumber before the plant died.
In a community garden controlling insects is especially challenging. Rodale's book, Vegetable Garden Problem Solver, gives excellent advice on controlling insects organically.
I do not know of any resistant varieties.
Good cleanup in the fall will help to remove adult insects. Planting later in the season will avoid the first crop of insects. Using row covers until flowering helps avoid early infestations. Hand picking and using sticky traps helps.
As a last measure, spray with Pyrethrins, which will also destroy some beneficial insects.