Midrash su Levitico 23:14

2) "the meal-offering of your bikkurim": I might think this is an individual offering, (but) it is written here "bikkurim," and, elsewhere, (in respect to the two loaves, Vayikra 23:17): "bikkurim." Just as "bikkurim" there are a communal offering, so, bikkurim here. These are the words of R. Akiva. R. Shimon says: I might think this is an individual offering, but (this is negated by) its being written (Vayikra 23:14): "And you shall bring the omer, the first (grain) of your harvest, to the Cohein." If you say that this (in our verse) is an individual offering, and that is a communal offering, this cannot be. For if this is "bikkurim to the L–rd," then that is not the first of the harvest; and if that is the first of the harvest, then this is not "bikkurim to the L–rd." (Note:) Things omitted here (in connection with the omer offering [e.g., "waving" and the permitting of chadash (the new crop)] are written there.

3) "first-fruits (bikkurim) to the L–rd": R. Shimon says: I might think this is an individual offering, but (this is negated by) its being written (Vayikra 23:14): "And you shall bring the omer the first grain of your harvest, to the Cohein." If you say that this is an individual offering, and that is a communal offering, this cannot be. For if this is bikkurim to the L–rd," then that is not the first of the harvest; and if that is the first of the harvest, then this is not "bikkurim" to the L–rd." (Note:) Things omitted there (in connection with the omer offering [e.g., "lifting" and the permitting of chadash (the new crop)] are written here. (See Dibbura d'Nedavah Chapter 15:2)

4) as it is written (Vayikra 23:14): "And bread, and kali, and karmel you shall not eat until this self-same day, until you have brought the offering of your G d." "And if you offer a meal-offering of bikkurim to the L–rd": This is the meal-offering of the omer. From which (grain) does it come? From barley. — But perhaps it comes from wheat! R. Eliezer says (to negate this): It is written here (Vayikra 2:14): "aviv" (grain in the ear), and also in respect to Egypt (Shemoth 9:41). Just as "aviv" in respect to Egypt is barley, so, "aviv" here. R. Akiva says: It is written that the congregation is to bring bikkurim (the omer) on Pesach and that the congregation is to bring bikkurim (the two loaves) on Atzereth (Shavuoth). Just as we find that of that kind (of grain [i.e., wheat]) of which the individual brings his obligatory offering, the congregation brings its obligatory offering (the two loaves) on Atzereth — so, of that kind (i.e., barley), of which the individual brings his obligatory offering (the meal-offering of rancor of the sotah), the congregation is to bring its bikkurim (the omer) on Pesach. From which kind does the individual bring his obligatory offering? From barley. The congregation, too, is to bring its obligatory offering only from barley. An alternate derivation: If you say (that he brings it) of wheat, then the two loaves (which are of wheat) could not be (called) "bikkurim" (first fruits).