Grass family, Poaceae (Gramineae).

CFR · 2024-01-01 · US · Title 7

Kinds of seed: Bentgrasses, bluegrasses, bluestems, bromes, cereals, fescues, millets, orchardgrass, redtop, ryegrasses, sorghums, timothy, turf timothy, wheatgrasses, and all other grasses listed in § 201.2(h). (a) Cereals: Agrotricum, barley, oat, rye, mountain rye, wheat, wheat × agrotricum, and triticale. (1) General description. (i) Germination habit: Hypogeal monocot. (ii) Food reserves: Endosperm. The scutellum is a modified cotyledon which is in direct contact with the endosperm. During germination the scutellum remains inside the seed to absorb nutrients from the endosperm and transfer them to the growing seedling. (iii) Shoot system: The shoot consists of the coleoptile, leaves enclosed in the coleoptile, and the mesocotyl. The coleoptile elongates and pushes through the soil surface; the mesocotyl may elongate depending on the variety and light intensity, but may not be discernible. Splitting of the coleoptile occurs naturally as a result of growth and emergence of the leaves. (iv) Root system: A primary root and seminal roots. The primary root is not readily distinguishable from the seminal roots; therefore, all roots arising from the seed are referred to as seminal roots. (2) Abnormal seedling description. (i) Shoot: (A) Missing. (B) No leaf. (C) Leaf extending less than halfway up into the coleoptile. (D) Leaf extensively shredded or split. (E) Spindly or watery. (F) Grainy, spirally twisted, shredded, and weak. (G) Deep open cracks in the mesocotyl. (ii) Root:

official document · source cfr-2024 · id 7:§ 201.56-5