I can't make an absolute judgment, but it is very difficult for concentration disorders to occur due to overwatering. I think there may be other causes. The phenomenon of grape leaves drying up can also occur due to JS, even if it is not overwatering.
If you have the opportunity, overwatering I recommend you to try a repeat experiment in this situation.
I have planted about 10 vineyards in the field and am doing various experiments. The core of the experiment is how to overcome the damage of JS. I am looking forward to good results.
