My grape vines, planted last spring and summer, are just coming out of dormancy. I was checking the buds yesterday and noticed on the last 4-5 feet of one vine, there was a spotty black mildewy looking fungus concentrated around the knuckles of the buds. When I checked the rest of my vines, most had at least a few feet affected at the ends of last year's growth.

I looked online for a fungus that visually matched what I saw, but powdery mildew is whitish, and most pics of grape diseases were on bunches of fruit or leaves/growing vines, not on bare, dormant vines.
I didn't want the emerging buds to get infected, so I clipped off what appeared to have the mold/fungus and set it in the burn pile. I plan on getting some fungicide and spraying ASAP, but I wanted to know what I'm up against. Maybe I had powdery mildew last year and didn't see it...and it turns black when overwintered? I only sprayed for insects last summer and water via a soaker hose--the vines seemed fine...even had a growth spurt when we finally got some much needed rain in early August.

I'll try to post a pic or two before I burn the bad vines. I had to cut one lovely vine to about 3 feet tall :( I'm hoping I didn't jump the gun on pruning out the affected wood...the buds seemed to be a bit retarded in growth compared to the buds emerging on the unaffected portions of vine.

Any ideas?