We apologize for the delayed response, but due to technical difficulties your submission was inadvertently misplaced in an incorrect folder. Our technical staff has been advised about this problem and again we are sorry for the delay. We are in the process of refining our app to make it even better for our users. Your plant likely has powdery mildew. When selecting varieties select those varieties that are listed as disease resistant. This is not the time for squash because they are warm season crops and will be susceptible to disease during the winter season. To prevent re-seeding, clip off flowers before they form fruit and you can also apply a pre-emergent recommended by your local garden center to prevent seeds from germinating.