Does planting marigolds in amonst the runner beans help keep diseases down?

I think black fly is the biggest problem with beans and my books suggest planting nasturtium as these are more attractive to the pest. some other companion planting:
Basil – wards off whitefly when planted amongst tomatoes
Nasturtium – attracts aphids away from beans
Alliums – confuse carrot fly and protect against slug damage
Lavender – confuses pests
Nettles – attract cabbage white butterflies, keeping them away from brassica crops
I dont know if any plant would prevent disease, only in that it would stop disease carrying insects attacking your plants. Welcome to GoY