Just looking at the manual, there doesn't appear to be an operation for that. However, I did dee a HINT notation that if you press Record while it's playing it will record from that point. So, if you're really quick you could try that for punching in and quickly stop it where needed. Could get messy. This would probably work ok with your hands free singing a vocal - if you're doing this solo, or punching in another musician.
This really sucks not to have that feature, especially since markers are utilized for other things.