I’m starting to study for the N5 exam in July and made a quick Excel sheet to compare the grammar supposedly needed and what’s covered in Genki. I added Minna no Nihongo, but I don’t use it so it’s taking a bit longer. If some of your are familiar with MNN, maybe you can help me fill the gaps. And if you have comments or want to point things that are incorrect, let me know.
I used the N5 grammar list on this website as a basis: http://www.tanos.co.uk/jlpt/skills/grammar/
EDIT: Thanks everyone for your help, I think the table is pretty much complete. For people wondering what is covered in those textbooks, it seems that both Genki I and MNN I cover more than is needed for the N5 level (just a few points need to be checked in subsequent volumes).
If someone would like to add their textbook to the list (Japanese for busy people, perhaps), let me know. I’m not yet doing N4, let alone N3, but if someone wants to join efforts and add those levels, you can also contact me and I can give you editing rights to work on a new spreadsheet in the same file).