Group Nomenclature in Cultivated Plant Classification
In the specialized worlds of horticulture and agriculture, naming plants accurately is essential for clear communication. While botanical taxonomy follows strict rules for wild species, cultivated plants require a different set of standards. One of the most important formal categories used to organize these plants is the Group. Defined by the International Code of Nomenclature for Cultivated Plants (ICNCP), a Group allows growers and scientists to categorize plants that share specific, recognizable characteristics.
ไม่มีภาพประกอบ
Understanding the Formal Group Category
A Group is a formal taxon used to collect cultivars or individual plants that exhibit a defined similarity. This categorization is distinct from general plant taxonomy; it is specifically designed for horticultural and agricultural contexts. While a botanical name might use different classifications like a variety or a subspecies, the Group serves the needs of those managing cultivated varieties.
Evolution of the Terminology
The terminology used to describe these collections has evolved over time. Since 1969, the category was known as the "cultivar-group." However, in 2004, the ICNCP updated the rules, replacing the hyphenated term with the simpler Group or the abbreviation Gp. This change also introduced a subtle shift in meaning: while a "cultivar-group" was strictly defined as a collection of cultivars, a modern "Group" may include individual plants as well.
This category also replaced the older term convariety (abbreviated as convar.), which did not always require the inclusion of named varieties.
Key Facts
- Formal Symbol: Represented by the word "Group" or the abbreviation "Gp".
- Capitalization: The word "Group" must always be capitalized in a botanical name.
- Formatting: Unlike the Latin epithet, the Group name is not italicized.
- Scope: Groups can include multiple species within a single genus if they share a trait, such as the Iris Dutch Group.
- Non-Exclusivity: A single plant can belong to multiple Groups (e.g., both a "Maincrop Group" and a "Red-skinned Group") depending on the classification purpose.
Rules of Orthography and Writing
Proper writing, or orthography, ensures that plant names remain standardized globally. When writing a Group name, every word should be capitalized, except for conjunctions, prepositions, or specific linguistic customs (such as lowercase letters following a hyphen in terms like "Red-skinned").
Standard Formatting Examples
The Group name follows the italicized Latin epithet. It can also be applied after a common (vernacular) name. Common ways to write these include:
- Lilium Darkest Red Group
- Neofinetia falcata Hariba Group
- hollyhock Chater's Double Group
For clarity in long names, the Group may be placed in parentheses. While the ICNCP suggests placing the Group after the epithet, in practical use, the cultivar name in single quotation marks sometimes appears first:
- Solanum tuberosum (Maincrop Group) 'Desiree'
- Solanum tuberosum 'Desiree' Maincrop Group
ไม่มีภาพประกอบ
Summary of Nomenclature Differences
| Term | Context | Formatting Rule |
|---|---|---|
| Group (Capitalized) | Formal ICNCP taxon | Capitalized, not italicized |
| group (lowercase) | Informal taxon | Not recognized in ICBN |
| Gp | Standard abbreviation | No terminal period (unlike "var.") |
| cultivar-group | Pre-2004 terminology | Older, hyphenated version |
Frequently Asked Questions
What is the difference between "group" and "Group"?
The distinction is one of formality. A capitalized Group is a formal taxon defined by the ICNCP. A lowercase group refers to an informal taxon that is not recognized by the International Code of Nomenclature for algae, fungi, and plants (ICBN).
Can a Group include more than one species?
Yes. A Group is often united by a distinct common trait and can include members of more than one species within the same genus. An example is the Iris Dutch Group, which consists of early-flowering cultivars.
How is the abbreviation "Gp" different from other botanical abbreviations?
The abbreviation "Gp" is used without a period at the end. This differs from higher-level taxonomic abbreviations used in botany, such as "var." for variety or "f. sp." for forma specialis.
What happens if a species loses its botanical status?
If a plant species loses its taxonomic status in botany but retains horticultural or agricultural value, it can still meet the criteria for a Group. In such cases, its former botanical epithet can be reused, such as Hosta fortunei becoming the Hosta Fortunei Group.
Are Groups mutually exclusive?
No. A single plant can be categorized into multiple Groups simultaneously. For example, a potato could be classified under both the Maincrop Group and the Red-skinned Group depending on the specific purpose of the classification.