פירוש על כלאים 1:3

Turnips and the cabbage turnip, cabbage and cauliflower, beet and rumex do not constitute kilayim one with the other. Rabbi Akiva added: garlic and small wild garlic, onion and small wild onion, lupine and wild lupine do not constitute kilayim one with the other.
Again, the mishnah deals with pairs of seeds that may be grown together.