What does "Bikurei Admasenu" refer to?
Ibn Ezra: They are the Omer and Shtei ha'Lechem.
Malbim: They are [Bikurim of] wheat and barley.
What do we learn from "Bikurei Kol Pri Chol Etz"?
Rashi: Bikurim apply to all fruits, [at least] mid'Rabanan 1 .
Ibn Ezra: It is only the fruits in the verse "Eretz Chitah u'Se'orah..." - the seven species.
Malbim: It is the five tree fruits among the seven species. The Torah did not give a Shi'ur for Bikurim, so they accepted to bring a proper gift - one part in 60, like Chachamim enacted 2 .
Malbim: This is astounding! The Yerushalmi in Bikurim says that if one brought not from the seven species, it did not become Kadosh!
So rules Rambam (Hilchos Bikurim 2:17). Kesef Mishneh - the Yerushalmi and Chulin 137b imply so. (Most texts in Chulin say 'Ein Lah Shi'ur mid'Oraisa', i.e. Pe'ah, but Bikurim have no Shi'ur even mid'Rabanan! - PF)
