cultivar

noun

A unvarying variety of plant produced by selective hybridization and maintained by vegetative propagation or by inbred seed; abbreviated cv. A term contracted from `cultivated variety' defined under the International Code of Nomenclature of Cultivated Plants (1969) as `an assemblage of cultivated plants which is clearly distinguished by any characters (morphological, physiological, cytological, chemical, or others), and which, when reproduced (sexually or asexually), retains its distinguishing characters.' This term is essentially different from the concept of botanical variety, which is always in the Latin form prescribed by the International Code of Botanical Nomenclature. These plants are named at three main levels: Genus, species, and cultivar, of which the first two are governed by the Botanical Code and the last is a `fancy name' in a modern language with capital initial letters and distinguished clearly from the botanical name or accepted common name by being enclosed in single quotation marks (e.g.,'Hamlin' sweet orange) or preceded by cv (e.g., Citrus sinensis Osbeck cv. Hamlin. Examples of cultivar categories distinguished under the Cultivated Plant Code follow: A clone or several closely similar clones, including distinguishable bud mutations derived from a clone. Note, however, that neither a clone nor any other category listed is designated as a cultivar (variety) until it has been released; i.e., when the name is validly published under prescribed rules. One or more lines of normally self-pollinating individuals or inbred lines of normally cross-pollinating individuals. Cross-pollinated individuals that may show genetic differences but have one or more characters by which they can be differentiated from other cultivars of like or different origin. An assemblage of individuals reconstituted on each occasion by crossing, including single crosses, double crosses, three-way crosses, top crosses, and intervarietal hybrids the primary difficulty in the foregoing categories, which refer to cultivated plants produced principally by systematic breeding and release to growers, is the necessity for continual redefinition of guidelines for classifying populations (i.e. the establishment of precise criteria), particularly those of cultivated plants produced by sexual means such as agricultural agronomic), vegetable, tree, shrub, and flower seeds. General practice for the latter includes the substitution of common for scientific names and variety for cultivar, variety being specifically defined as the International Code of Nomenclature of Cultivated Plants. Cf. Federal Seed Act of 1938 as Amended and Regulations (1976). Guidelines for classifying cultivated plant populations (1978), and Plant patents.