Cultivar, Strain, Line, Accession, and Clone
Use plant-genetic-resource terms precisely and attach each name to a reproducible biological unit.
Use plant-genetic-resource terms precisely and attach each name to a reproducible biological unit.
Core science
These words describe different kinds of identity. A cultivar or protected variety is a plant grouping, not merely a memorable name. A line is defined by breeding history and may still segregate. An accession is a conserved sample and documentation unit. A clone is a vegetatively propagated ramet derived from one source genotype.
In cannabis commerce, strain often labels a product or claimed lineage without an enforceable identity standard. Samples sold under one name have shown substantial genetic differences, while differently named samples can be close. The word can be retained for audience recognition, but it must not replace source, generation, clone code, or test data.
Seed lots from one named cultivar are not equivalent to a single clone. A clone name should refer to a documented source plant or reference sample. A line name should include generation, family, and selection history. An accession identifier must remain tied to the conserving institution and acquisition record.
Why this matters in cultivation
- Use a layered identity string: displayed name; breeder or repository; cultivar, line, accession, or clone status; generation or seed lot; internal plant ID; and verified genotype or chemotype records.
- Never rename material to match appearance or aroma. Quarantine unknowns under a temporary code until provenance and tests support a controlled designation.
Measure and record
Displayed name
Exact spelling, breeder or source, date received, and claims supplied.
Biological unit
Clone, seed lot, family, line, accession, population, or unknown.
Propagation history
Parent IDs, generation, lot, mother source, number of passages, and dates.
Evidence
Reference sample, genotype panel, chemistry, morphology, photographs, and certificates.
Name changes
Old name, new controlled name, authority, reason, date, and affected inventory.
Common misconceptions
Misconception: A strain name is a genotype
Correction: The same market name can contain genetically divergent material.
Misconception: A seed cultivar is a clone
Correction: Seed reproduction creates segregating individuals unless the material is exceptionally uniform.
Misconception: An accession is a cultivar
Correction: An accession may represent a cultivar, line, landrace, wild population, or other conserved sample.
Evidence limits and uncertainty
Legal definitions of cultivar or variety vary by jurisdiction and protection system. Genetic similarity alone does not establish ownership, distinctness, uniformity, stability, or right to use a name.
Check your reasoning
- For "Cultivar, Strain, Line, Accession, and Clone", explain the mechanism behind this objective: Use plant-genetic-resource terms precisely and attach each name to a reproducible biological unit. Which observation or measurement would best test whether that mechanism is operating in the real crop?
- A learner claims, "A strain name is a genotype" Use the lesson’s science and evidence limits to explain why that claim is unreliable, then name one observation or measurement that could separate the competing explanations.
- Applied case — Use a layered identity string: displayed name; breeder or repository; cultivar, line, accession, or clone status; generation or seed lot; internal plant ID; and verified genotype or chemotype records. Build a verification plan using the lesson’s record set (Displayed name, Biological unit, Propagation history). What would you compare before and after the action, and what result would make you revise the original interpretation?
Require lesson-specific evidence, not memorized universal targets. Open the rationales after you have written or discussed your own answer.
Answer rationale 1: Mechanism / workflow rationale
- A strong answer should connect the response to the lesson objective: Use plant-genetic-resource terms precisely and attach each name to a reproducible biological unit.
- These words describe different kinds of identity. A cultivar or protected variety is a plant grouping, not merely a memorable name. A line is defined by breeding history and may still segregate. An accession is a conserved sample and documentation unit. A clone is a vegetatively propagated ramet derived from one source genotype.
- In cannabis commerce, strain often labels a product or claimed lineage without an enforceable identity standard. Samples sold under one name have shown substantial genetic differences, while differently named samples can be close. The word can be retained for audience recognition, but it must not replace source, generation, clone code, or test data.
- The most useful verification evidence includes Displayed name: Exact spelling, breeder or source, date received, and claims supplied.
- Keep this limit explicit: Legal definitions of cultivar or variety vary by jurisdiction and protection system. Genetic similarity alone does not establish ownership, distinctness, uniformity, stability, or right to use a name.
Answer rationale 2: Misconception rationale
- The shortcut is unreliable because the lesson explicitly teaches a more conditional explanation.
- Representative misconception: A strain name is a genotype: The same market name can contain genetically divergent material.
- These words describe different kinds of identity. A cultivar or protected variety is a plant grouping, not merely a memorable name. A line is defined by breeding history and may still segregate. An accession is a conserved sample and documentation unit. A clone is a vegetatively propagated ramet derived from one source genotype.
- A useful discriminator is Biological unit: Clone, seed lot, family, line, accession, population, or unknown.
- Do not overextend the conclusion beyond this limit: Legal definitions of cultivar or variety vary by jurisdiction and protection system. Genetic similarity alone does not establish ownership, distinctness, uniformity, stability, or right to use a name.
Answer rationale 3: Applied verification rationale
- In practice: Use a layered identity string: displayed name; breeder or repository; cultivar, line, accession, or clone status; generation or seed lot; internal plant ID; and verified genotype or chemotype records.
- Record before action: Displayed name: Exact spelling, breeder or source, date received, and claims supplied.
- Also record: Biological unit: Clone, seed lot, family, line, accession, population, or unknown.
- After the action, repeat the same measurement or observation so the comparison is valid.
- Revise the interpretation if the result conflicts with the lesson limit or the expected response: Legal definitions of cultivar or variety vary by jurisdiction and protection system. Genetic similarity alone does not establish ownership, distinctness, uniformity, stability, or right to use a name.
Related lessons
Sources and evidence
- International Union for the Protection of New Varieties of Plants. 1991 Act of the UPOV Convention: variety definition.
- FAO. Plant genetic resources concepts and definitions: accession.
- Schwabe A.L. and McGlaughlin M.E. (2019). Genetic tools weed out misconceptions of strain reliability in Cannabis sativa. Journal of Cannabis Research 1:3.
- Jin D. et al. (2021). Classification of cannabis strains in the Canadian market with discriminant analysis of principal components. PLOS ONE 16:e0253387.
Downloads
No lesson-specific download is approved for this release. Use browser print/save-to-PDF when you need an offline reading copy.