Basically all filesystems that are compiled into the kernel you are using.

(otherwise it won’t be able to access the /root partition and the whole thing won’t boot)

You can use those listed filesystems to install your linux into it (/root-partition)… but you can not use VFAT-Family(FAT16,FAT32 and probably also not exFAT :-D) Debian8 says. They must know.

So it seems the Debian8 default kernel comes with support for those filesystems.

you can also NOT use SWAP as root partition 😀 (damn it)