If you are a user of Google+ then you must be getting notifications in your inbox. There might be some notfications useful but might be there is a chance that your inbox is flooded with notfications, so in this case you might be looking out some way to disable Google+ eamail notification.
To disable Google+ email notification,you need to follow following steps:
1. Click to open the menu at the top right-hand corner next to profile picture on Google+ and then click on Account.
2. After getting the new window, click on the Google+ from the menu available on the left.
3. Now get down to the alerts area and remove the checkbox(ticked) by clicking over the boxes available next to the events you do not want to be notified aboutvia email.