-Diatonic Modes and the Chords Built Off the Degrees-
Capitals are major, lower case are minor. ° is diminished.
Ionian - I ii iii IV V vi vii°
Dorian - i ii III IV v vi° VII
Phrygian - i II III iv v° VI vii
Lydian - I II iii iv° V vi vii
Mixolydian - I ii iii° IV v vi VII
Aeolian - i ii° III iv v VI VII
Locrian - i° II iii iv V VI vii
This tells you what chords are major, minor, or diminished relative to each other. It works for any key.
As for harmonic minor, it is very similar to aeolian.
i ii° III iv V VI vii°
The important thing to remember it to play a V chord whenever the raised seventh degree is played.
For the diminished scale, which one are you refering to?