u/TraversingPotato

I bought a couple bare root marquis grape plants a month ago and planted them in separate 20 gallon grow bags. One of the vines started to push new growth, but since leaf emergence, the leaves have a silvery, webby like coating on the surface. I only realized there was an issue when a new vine sprouted from below the soil with a vibrant green color. I scratched the surface of one of the open leaves to see if it was superficial or if it was part of the leaf and found it it's something on the leaf. I'm wondering - is this powdery mildew or some other fungus, and what can I do to save the plants? Both of them seem well rooted, one hasn't pushed any leaf growth yet, but I'm worried that this will spread to both plants and affect their health