Kinds of seed: Beet, Swiss chard, fourwing saltbush, spinach, New Zealand spinach, and forage kochia.
(a) General description.
(1) Germination habit: Epigeal dicot.
(2) Food reserves: Leaf-like cotyledons and perisperm.
(3) Shoot system: The hypocotyl elongates carrying the cotyledons above the soil surface. The epicotyl usually does not show any development within the test period.
(4) Root system: A primary root; secondary roots may develop within the test period.
(5) Seedling: Frequent counts should be made on multigerm beet since the growing seedlings will separate from the cluster making it difficult to identify the source. Any cluster which produces at least one normal seedling is classified as normal; only one normal seedling per cluster is to be counted (see § 201.56(d)). Toxic substances from the clusters of beet and Swiss chard may cause discoloring of the hypocotyl and/or root. Seedlings which are slightly discolored are to be classified as normal; however, if there is excessive discoloration, retest by the method in § 201.58(b)(3).
(b) Abnormal seedling description.
(1) Cotyledons:
(i) Less than half of the original cotyledon tissue remaining attached.
(ii) Less than half of the original cotyledon tissue free of necrosis or decay.
(2) Epicotyl:
(i) Missing. (May be assumed to be present if 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) None.
(ii) Weak, stubby, or missing primary root with weak secondary or adventitious roots.
(iii) For discolored roots of beet and Swiss chard, see § 201.58(b)(3).
(5) Seedling:
(i) One or more essential structures impaired as a result of decay from primary infection. (For discolored seedlings of beet and Swiss chard, see § 201.58(b)(3).)
(ii) Albino.
[59 FR 64500, Dec. 14, 1994]