Mine get them too but it doesn't seem to keep the plants from producing. You might try spacing the plants a little further apart so fungus doesn't get established (I've had some fungus problems in the past due to crowding), and make sure you have predator habitat plants nearby. If you can shoot the bean plants with a strong spray of water periodically, that might help knock off some of the bad guys.
She'll be back. I'm just gonna wait here. With this tiny ad:
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