Kinds of seed: Broccoli, brussels sprouts, cabbage, Chinese cabbage, cauliflower, collards, garden cress, upland cress, water cress, kale, Chinese kale, Siberian kale, kohlrabi, mustard, pakchoi, radish, rape, rutabaga, and turnip.
(a) General description.
- (1) Germination habit: Epigeal dicot.
- (2) Food reserves: Cotyledons which expand and become thin, leaf-like and photosynthetic. In Brassica, Sinapis, and Raphanus, the cotyledons are bi-lobed and folded, with the outer cotyledon being larger than the inner.
- (3) Shoot system: The hypocotyl elongates and carries the cotyledons above the soil surface; the epicotyl usually does not show any development within the test period.
- (4) Root system: A long primary root.
(b) Abnormal seedling description.
(1) Cotyledons:
- (i) Decayed at point of attachment.
- (ii) Less than half of the original cotyledon tissue remaining attached.
- (iii) Less than half of the original cotyledon tissue free of necrosis or decay.
(2) Epicotyl:
- (i) Missing. (May be assumed to be present if the cotyledons are intact.)
- (ii) [Reserved]
(3) Hypocotyl:
- (i) Deep open cracks extending into the conducting tissue.
- (ii) Malformed, such as markedly shortened, curled, or thickened.
- (iii) Watery.
(4) Root:
- (i) Weak, stubby, or missing primary root. (Secondary roots will not compensate for a defective root.)
- (ii) [Reserved]
(5) Seedling:
- (i) One or more essential structures impaired as result of decay from primary infection.
- (ii) Albino.
[59 FR 64501, Dec. 14, 1994]