slowness in sprouting, and one or more other abnormalities; (v) a rotted cotyledon, provided the decay is not the result of improper test conditions; or (vi) various combinations of the abnormalities described in this subparagraph. (b) Asparagus. By the end of the test period a normal asparagus seedling should have a long, slender root, a fairly long epicotyl, an intact terminal bud, and the seedling should not be broken away from the cotyledon. (1) Normal seedlings include those that have: (i) A long, slender root; (ii) a long, well-developed epicotyl with terminal growing point; (iii) the cotyledon attached to the seedling; or (iv) slight infestation by fungi, provided none of the essential seedling structures have been damaged. (2) Abnormal seedlings include those that have: (i) No root, or a very stubby root with weak secondary root development; (ii) a malformed epicotyl, which may be thickened, shortened, or twisted; (iii) no terminal growing point or bud; (iv) cotyledon broken away from the seedling; (v) decayed epicotyl, provided the decay is not the result of improper test conditions; or (vi) various combinations of the abnormalities described in this subparagraph. [20 F. R. 7935, Oct. 21, 1955] § 201.56-8 Flax family (Linaceae). (a) Kind of seed: Flax. (b) By the end of the germination test a normal flax seedling should have a well-developed primary root, a long hypocotyl, two intact cotyledons, and a small epicotyl. (1) Normal seedlings include those that have: (i) A long, slender root, usually with root hairs; (ii) a short or stubby primary root, provided secondary root development is strong and the hypocotyl is of normal length or approximately so; (iii) a long, well-developed hypocotyl with no breaks or lesions extending into the conducting tissues; (iv) at least one attached cotyledon, provided the epicotyl is not injured; (v) variously broken or cracked cotyledons, provided the other seedling parts appear normal; or (vi) slight infection by fungi, provided none of the essential seedling structures have been damaged. (2) Abnormal seedlings include those that have: (i) A stubby or no primary root, provided the secondary root development is weak, a condition usually associated with a shortened hypocotyl; (ii) a malformed hypocotyl, which may be twisted, thickened, or shortened; (iii) deep cracks or lesions on the hypocotyl, extending into the conducting tissues; (iv) both cotyledons broken off; (v) one cotyledon broken off if the epicotyl is also injured (vi) decayed cotyledons or other essential seedling structures, provided the decay is not the result of improper test conditions; or (vii) various combinations of the abnormalities described in this subparagraph. [20 F. R. 7935, Oct. 21, 1955] § 201.56-9 Mallow family (Malvaceae). (a) Kinds of seed: Cotton and okra. (b) By the end of the germination test a perfectly normal seedling should have a long, well-developed root with root hairs, a long hypocotyl, two attached green leaflike cotyledons, and a small epicotyl. (1) Normal seedlings include those that have: (i) A well-developed, long, slender root, usually with root hairs; (ii) no primary root but strong secondary roots, provided the hypocotyl is of normal or approximately normal length; (iii) a long, well-developed hypocotyl with no breaks or deep grainy lesions which might interfere with the conducting tissues; (iv) at least one cotyledon and intact epicotyl; (v) slight infection by fungi, provided none of the essential seedling structures have been damaged; or (vi) yellowish hypocotyls or roots of cotton which may appear diseased, provided the cotyledons are free of infection (the seedcoat must be peeled back on young seedlings to determine this condition of the cotyledons). (2) Abnormal seedlings include those that have: (i) No root or very stubby roots, usually associated with a shortened hypocotyl; (ii) stubby roots and a thickened hypocotyl resulting from chemical treatment of seed, such as often occurs on delinted cottonseed; (iii) malformed hypocotyl, which may be curled, thickened, or shortened; (iv) deep cracks or grainy lesions on the hypocotyl which appear to interfere with the conducting tissues; (v) epicotyl absent, even though one or both cotyledons are attached; (vi) decayed cotyledons and hypocotyl, provided the decay did not spread from another seed or was not the result of improper test conditions; or (vii) various combinations of the abnormalities described in this subparagraph. [20 F. R. 7935, Oct. 21, 1955] § 201.56-10 Spurge family (Euphorbiaceae). Kind of seed: Caster bean. (a) Normal seedlings include those that have: (1) A primary root or a set of secondary or adventitious roots sufficient to anchor the seedling when grown in soil or sand, provided the hypocotyl is not badly shortened; (2) a fairly welldeveloped hypocotyl with no prominent breaks or stem lesions which might interfere with the conducting tissues; (3) an epicotyl with terminal bud; or (4) slight infection by fungi or bacteria, provided the essential seedling parts have not been seriously damaged and appear to be able to carry on their normal functions at the time of evaluation. (b) Abnormal seedlings include those that have: (1) No primary root or welldeveloped adventitious or secondary roots; (2) a malformed stem, which may be characterized by severe open splits, and curled, shortened or thickened hypocotyl; (3) no epicotyl, or an epicotyl without the terminal bud; (4) decay caused by microorganisms carried by the individual seed or seedling being evaluated; or (5) various combinations of the abnormalities described in this subparagraph. [20 F. R. 7935, Oct. 21, 1955] § 201.56-11 Miscellaneous plant families. Kinds of seed by families: Benne family (Pedaliaceae)-Sesame. Carrot family (Umbelliferae)-carrot, celery, celeriac, parsley, parsnip. Dichondra family (Dichondraceae)Dichondra. Knotweed family (Polygonaceae) -Buckwheat, sorrel, rhubarb. Nightshade family (Solanaceae) -Eggplant, pepper, tomato, husk tomato. Geranium family (Geraniaceae) —Alfileria. (a) In this group of plant families, normal seedlings include those that have: (1) A well-developed primary root, usually with root hairs; (2) a stubby root or no primary root, provided the secondary root development is strong and the hypocotyl is near normal length as is frequently encountered in tomato seedlings; (3) a long, well-formed hypocotyl with no prominent breaks or lesions extending into the conducting tissues; (4) at least one attached cotyledon, provided the epicotyl is intact and the seedling is otherwise normal (a tiny epicotyl may be observed in seedlings left in test for final evaluation); or (5) slight infection by fungi, provided none of the essential seedling structures have been damaged (infection is likely to occur in rhubarb in which case retests may be advisable). (b) Abnormal seedlings include those that have: (1) A stubby root or no primary root, provided there is weak secondary root development; (2) a malformed hypocotyl, which may be twisted, thickened, or shortened; (3) deep cracks or lesions on the hypocotyl extending into the conducting tissues; (4) both cotyledons, or one cotyledon and epicotyl, broken off; (5) two enlarged cotyledons, but hypocotyl short and usually malformed; (6) decayed cotyledons or hypocotyl, provided they are not the result of improper test conditions; or (7) various combinations of the abnormalities described in this paragraph. [20 F. R. 7935, Oct. 21, 1955] $201.57 Hard seeds. Seeds which remain hard at the end of the prescribed test because they have not absorbed water, due to an impermeable seed coat, are to be counted as "hard seed." If at the end of the germination period provided for legumes, okra, cotton and dichondra in these rules and regulations there are still present swollen seeds or seeds of these kinds which have just started to germinate, all seeds or seedlings except the above-stated shall be removed and the test continued for 5 ad ditional days and the normal seedlings included in the percentage of germination. [5 F. R. 33, Jan. 4, 1940, as amended at 10 F. R. 9952, Aug. 11, 1945; 20 F. R. 7936, Oct. 21, 1955] §201.57a Dormant seeds; firm ungerminated seeds. Dormant seeds means seeds, other than hard seeds, which fail to germinate when provided the specific germination conditions for the kind of seed in question. Firm ungerminated seeds means seeds, other than hard seeds, which neither germinate nor decay during the prescribed test period and under the prescribed test conditions. [20 F. R. 7936, Oct. 21, 1955] § 201.58 Substrata, temperature, duration of test, and certain other specific directions for testing for germination and hard seed. Specific germination requirements are set forth in table 2 in paragraph (c) to which the following paragraphs (a) and (b) are applicable: (a) Definitions and explanations applicable to table 2—(1) Duration of tests. The following deviations are permitted from the specified duration of tests: Any test may be terminated prior to the number of days listed under "Final Count" if the germination of the sample has then been determined. The number of days stated for the first count is approximate and a deviation of 1 to 3 days is permitted. (Also, see subparagraph (5) of this paragraph and § 201.57.) (2) Light. When light is required the intensity for nondormant seed may be as low as 25 foot-candles. In the case of dormant seed of grasses such as occur in Agrostis tenuis, Poa compressa, and Lolium multiflorum the light intensity should approximate 100 foot-candles. (3) Moisture-on-dry-side. This term means that the moistened substratum should be pressed against a dry absorbent surface such as a dry paper towel or blotter to remove excess moisture. The moisture content thus obtained should be maintained throughout the germination test period. (4) Potassium nitrate (KNO,). These terms mean a two-tenths (0.2) percent solution of potassium nitrate (KNO1) shall be used in moistening the substratum. Such solution is prepared by dissolving 2 grams of KNO, in 1,000 ml. of distilled water. The grade of the potassium nitrate shall meet A. C. S. specifications. (5) Prechill. The term "prechill" means to place the seed on, or in, a moist substratum at a specified low temperature for a designated period of time. The prechilling period is not included in the duration of tests given in table 2, unless otherwise specified. (6) Predry. The term "predry” means to place the seed in a shallow layer at a temperature of 35° to 40° C. for a period of 5 to 7 days, with provisions for circulation of the air. (7) Substrata (Kinds). The symbols used for substrata are: B= between blotters TB= top of blotters T= paper toweling, used either as folded towel tests or as roll towel tests in horizontal or vertical position 8= sand or soil TS= top of sand or soil P= covered Petri dishes: with two layers of blotters; with one layer of absorbent cotton; with five layers of paper toweling; with three thicknesses of filter paper; or with sand or soil C= creped cellulose paper wadding (0.3inch thick Kimpak or equivalent) covered with a single thickness of blotter through which holes are punched for the seed that are pressed for about one-half their thickness into the paper wadding RB= blotters with raised covers, prepared by folding up the edges of the blotter to form a good support for the upper fold which serves as a cover, preventing the top from making direct contact with the seeds. (8) Temperature. A single numeral indicates a constant temperature. Two numerals separated by a dash indicate an alternation of temperature, the test to be held at the first temperature for approximately 16 hours and at the second temperature for approximately 8 hours per day. If tests are not subjected to alternating temperatures over weekends and on holidays they are to be held at the lower temperature during this time. In cases where two temperatures are indicated (separated by a semicolon) the first temperature shall be regarded as the regular method and the second as an alternate method. (9) Toxicity of substrata. If there is question as to whether a paper substratum is toxic to developing seedlings, check tests should be made on Whatman's No. 2 filter paper or its equivalent. Seeds of celery, celeriac, chicory, dandelion, endive, timothy, and Bermuda grass are particularly sensitive to toxic substrata. If root injury is evident on a substratum moistened with potassium nitrate, retests should be made on a substratum moistened with water or on soil. (b) Special procedures and alternate methods for germination referred to in table 2-(1) Alyce clover (Alysicarpus vaginalis); Swollen seeds. At the conclusion of the 21-day test period carefully pierce the seedcoat with a sharp instrument and continue the test for 5 additional days. Alternate method: The swollen seeds may be placed at 20° C. for 48 hours and then at 35° C. for 3 additional days. (2) Bahia grass (Paspalum notatum); removal of glumes-(i) Vars. Common and Argentine. Remove the glumes with the aid of a sharp scalpel. If the seed is fresh or dormant scratch the surface of the caryopsis lightly and use potassium nitrate. (ii) Var. Pensacola. The glumes shall not be removed for the germination test. (3) Beet, Swiss chard (Beta); preparation of seed for test. Before placing the seeds on the germination substratum they shall be soaked in water for 2 hours, using at least 250 ml. of water per 100 seeds, then washed in running water and the excess water should be blotted off. Samples producing darkened radicles should be retested in soil or by washing in running water for 3 hours and tested on "Kimpak," keeping the seed covered with slightly moist blotters. (4) Buffelgrass (Pennisetum ciliare); alternate method for dormant seed. The caryopses shall be removed from the fascicles and placed on blotters mois tened with a 0.2 percent potassium nitrate solution, in Petri dishes. The seeds from a fascicle should be arranged so they will not be confused with seeds from other fascicles during the test. The seeds are then prechilled at 5° C. for 7 days and tested at 30° C. in light for 21 additional days. Firm ungerminated seeds remaining at the conclusion of the test should be scratched lightly and left in test for 7 additional days. (5) Cotton (Gossypium spp.); dormant samples. Samples of cottonseed which do not respond to the usual method should be placed in a closed container with water and shaken until the lint is thoroughly wet. The moisture should then be blotted off. excess (6) Endive (Cichorium endivia); dormant samples. Add about 8 inch of tap water at the beginning of the test and remove excess water after 24 hours. (7) Lettuce (Lactuca sativa); light exposure. All samples should be given at least 2 hour of light after being placed on the moist substratum. Additional light during the test period is desirable for dormant samples and facilitates seedling interpretation for samples of low vigor. (8) Rescue grass (Bromus catharticus); dormant samples. Wash for 48 hours in running water, or soak for 48 hours, changing the water and rinsing each morning and night. (9) Rice (Oryza sativa); flood test. The seed is planted in moist sand. On the seventh day of the test add water to a depth of 14 inch above the sand level and leave for the remainder of the test. Only a final count is made. (10) Ryegrass (Lolium); fluorescence test. The germination test for the fluorescence of ryegrass shall be conducted in light (not to exceed 100 foot-candles) with white filter paper as a substratum. The test shall be conducted in a manner that will prevent the contact of roots of different seedlings. (11) Trifolium, Medicago, Melilotus, and Vicia faba; temperature requirements. The temperature for Trifolium spp., Medicago spp., Melilotus spp., and Vicia faba should never exceed 20° C. and a temperature of 17° to 18° is desirable. |