THE CERTIFICATION OF SEEDS

Variety Is a Key Word

MARTIN G. WEISS AND ELBERT L. LITTLE, JR.

To BUY, sell, and grow seeds and plants without confusion, we need a system of naming, distinguishing, and classifying the many thousand different kinds and varieties.

We must know also whether one lot of seeds or plants will give the same results as another or differs enough to require a separate name.

The key word "variety" is used for plant populations in two different ways for a botanical variety and for a cultivated variety.

THE PLANT KINGDOM comprises about 350 thousand known species, or kinds, of living wild plants, of which more than 250 thousand are seed plants. For comparison and study, these plants are classified by their characteristics into higher and higher ranks, or categories.

The scientific names of plants are in Latin form following the International Code of Botanical Nomenclature and are universally adopted around the world. The scientific name of a plant consists of its genus and species names. Trifolium pratense, for example, is the scientific name for red clover.

The most important rank, the species, is composed of individual plants or plant populations that are similar in appearance and can reproduce or breed among themselves and produce other individuals that resemble the parents.

A genus; plural, genera is a group of related species. The genus Trifolium, clover, includes also the species Trifolium repens, whiteclover, and many others.

A family is composed of related genera. Clovers, alfalfa, beans, peas, black locust, and similar plants belong to the legume family, Leguminosae.

Varieties have been recognized in some species. A variety (botanical variety, from Latin varietas, abbreviated "var.") is a rank or minor unit within a species composed of individuals which differ slightly from the others. Trifolium pratense var. foliosum, Orel clover, has been designated as a botanical variety of red clover.

Subspecies (abbreviated "subsp.") is an optional rank below the species but above the variety, based on minor characters and usually having an exclusive geographic range.

Form (abbreviated "f.") is an optional rank based on more trivial characters than a variety for example, color of flower or shape of the leaves.

Other groups sometimes are distinguished without scientific names.

A race is a group of individuals or population within a species that have general similarities discontinuous and distinct from other populations, although not sufficient for designation by a scientific name.

A geographic race is restricted in distribution to a particular region.

A physiologic race differs in life processes or functions but not necessarily in form for example, in resistance to disease or in rooting ability.

An ecotype is a race or ecological variation whose characters adapt it to a distinct habitat, such as soil and climate.

THE CULTIVATED VARIETY is the variety of cultivated plants, seeds, and commerce. Equivalent terms are commercial, agronomic, horticultural, and garden variety and cultivar, the shortened form.

The Federal Seed Act of August 9, 1939, defined kind as "one or more related species or subspecies which singly or collectively is known by one common name; for example, wheat, oat, vetch, sweetclover, cabbage, cauliflower, and so forth."

Under the Act, the term "variety" means "a subdivision of a kind which is characterized by growth, plant, fruit, seed, or other characters by which it can be differentiated from other sorts of the kind; for example, Marquis wheat, Flat Dutch cabbage, Manchu soybeans, Oxheart carrot, and so forth."

International Code of Nomenclature of Cultivated Plants 0958) contains this definition: "The term 'variety (cultivar)' denotes an assemblage of cultivated individuals which are distinguished by any characters (morphological, physiological, cytological, chemical, or others) significant for the purposes of agriculture, forestry, or horticulture, and which, when reproduced (sexually or asexually), retain their distinguishing features."

All individual plants of a variety have one or many characters in common that hold them together under the same name and serve for identification yet separate them from all others. Although the degree of uniformity differs within varieties, different samples of seeds and plants of the same variety generally perform similarly under the same conditions. The distinguishing characters must be maintained or inherited when the plants are reproduced over a period of years. The method of propagation, whether vegetative or by seeds, is immaterial.

Cultivated varieties are further distinguished from botanical varieties by their capitalized names in modern languages before the common name of the kind or species, as in Dollard red clover, or after the scientific name. Information for naming new varieties is given in Rules and Regulations Under the Federal Seed Act (sec. 201.34) and in the Code. The variety name shall not be misleading.

One variety often becomes known under several names. If no differences can be demonstrated between two or more so-called varieties, the name assigned by the originator is retained, with rare exceptions.

Rejected variety names that have become recognized through broad general usage are known as synonyms.

Some workers, especially in horticulture, have adopted the word "cultivar," an exact equivalent of variety, as a formal, scientific, and international term different from botanical variety. Variety, however, is firmly established in agriculture and is required under the Federal Seed Act and most State seed laws.

Rules and Regulations Under the Federal Seed Act define the term "lot of seed" as: "A definite quantity of seed identified by a lot number, every portion or bag of, which is uniform, within permitted tolerance, for the factors which appear in the labeling." A lot thus contains seed treated alike or processed in the same way but has no connotation relative to identity of the seeds.

Under the Federal Seed Act, the term "type" may mean "a group of varieties so nearly similar that the individual varieties cannot be clearly differentiated except under special conditions." The southern bromegrass varieties, for instance, such as Lincoln and Fischer, constitute a type that is distinct in leafiness and other characters from varieties of the northern type, such as Manchar.

Some seeds, such as lawn seed of grasses, represent mixtures of two or more varieties, often in definite percentages. As defined by Rules and Regulations Under the Federal Seed Act, "The term 'mixture' means seeds consisting of more than one kind or variety, each present in excess of 5 percent of the whole."

The word "strain" sometimes has been used to designate an improved selection of a variety. Under the Code, any such selection that shows sufficient differences from the parent variety to render it worthy of a name is to be regarded as a distinct variety. Strain has been applied to unnamed experimental varieties. It is considered broader than a variety. Because of the varied usage, it seems preferable not to associate strain with a certain level of classification. Whenever used, its meaning should be explained.

"Blend" is sometimes applied to mixtures of lots of seed within or between varieties but is not equivalent to a variety. For example, a blend may be composed of two seed lots of the same variety with different germination percentages mixed together. Or, blends may be mixtures of varieties or species prepared for different geographic regions.

The term "stock seed" often is applied loosely to designate seed used in the propagation and maintenance of a variety. Breeder seeds, foundation seeds, and registered seeds are frequently referred to as stock seed. In vegetable crops, the term "stock seed" has a more limited implication and often is used to denote foundation seed.

"Common" is a term applied to seed that cannot be identified as to variety and is often a mechanical or genetic mixture. In reference to alfalfa, the term "Common" has been used to denote local strains resulting from natural selection. Such selections have been identified by State of origin, such as Kansas Common, Oklahoma Common, or Utah Common.

A "brand" is a trademark adopted by a particular company or distributor for its seed or plants. A brand is neither a varietal designation nor part of a variety name. Instead, the brand precedes the variety name and may be applied to material of many different varieties or kinds of crops. Variety names have common usage and cannot be trademarked.

ASEXUALLY REPRODUCED CROPS arc propagated without the sexual processes of pollination and fertilization in seed formation.

These vegetatively propagated varieties are grown or multiplied from some part of the plant other than the seed. Familiar examples are vegetative propagation by roots, divisions, tubers, bulbs, cuttings, runners, layers, stem sections, grafts, and buds. Any plant part used to reproduce an individual asexually is called a propagule.

A plant grown from a part of another is in effect a continuation of the same tissues and hereditary characteristics.

Obviously, vegetatively propagated varieties are true to type and can be maintained pure indefinitely unless modified by the infrequent, sudden hereditary changes known as mutations or bud sports.

A clone consists of uniform plants or material derived from a single original individual and propagated entirely by vegetative means, as, for instance, by cuttings, divisions, or grafts. The original plant may have been wild, a chance variation or mutation, or a complex hybrid unlikely to breed true from seed.

The clonal members are all plants or progeny that originated by repeated multiplication from a single parent plant. A clonal variety consists of the vegetative propagules of one plant.

Some plants mature viable seeds by asexual reproduction (apomixis) without the normal process of fertilization. Instead of developing from the fertilized egg, the embryo plant in the seed may originate from mother tissues or from an unfertilized egg. An apomictic variety is a variety or clone that is propagated by seeds formed by asexual reproduction. Examples are found in bluegrass, dallisgrass, and other grasses.