What manga chapters of Minami-ke are serialized in anime and OVAs?
According to MangaUpdates:

Starts at Volume 1, Chapter 1 (Season 1)
Ends at Volume 6, Chapter 118 (Season 3)

These is a season 4 on top of that, but I couldn't find what it adapts.
Apparently the second season deviates from the manga or more accurately, includes non-manga episodes/content.
An excerpt from the link above:

It is also different in storytelling as it uses material not from the manga

As of August 2014, 12 tankōbon volumes of the series have been released, which as you say is still ongoing.