Molecular markers indicate that the narrow Québec endemics<i>Rosa rousseauiorum</i>and<i>Rosa williamsii</i>are synonymous with the widespread<i>Rosa blanda</i>
Bibliographic record
Abstract
Rosa rousseauiorum Boivin and Rosa williamsii Fern. are two rare roses in eastern Québec, whose taxonomic status is controversial. Morphological characters alone do not clearly differentiate these two taxa from each other or from the morphologically variable and widespread Rosa blanda Ait. We evaluated the taxonomic status of these two taxa, and of two other R. blanda segregates, Rosa subblanda Rydb. and Rosa johannensis Fern., through an analysis of RAPD, ISSR, and AFLP markers. We surveyed 86 individuals from 36 populations in eastern North America. Despite a high degree of polymorphism, principal coordinate analyses and the weighted pair group method with arithmetic averaging suggest no clustering of individuals that correspond to taxonomic boundaries. However, the closely related Rosa palustris Marsh. is clearly differentiated from the R. blanda s.l. taxa. When populations of R. blanda west of Québec are included, the principal coordinate analyses and Mantel tests indicate the presence of a significant eastwest geographic gradient. Analyses of molecular variation suggest that most of the observed variation occurs within taxa, rather than among taxa. A weak inter-taxon variation is nonetheless significant for RAPD and ISSR data, and a weak pattern dependent on geographical location is evident within the province of Québec. In accordance with studies based on morphological characters, molecular data indicate that R. rousseauiorum and R. williamsii should not be considered as species distinct from R. blanda.Key words: Rosa blanda, Rosa rousseauiorum, Rosa williamsii, Rosa johannensis, Rosa subblanda, RAPD, ISSR, AFLP, endangered plants, taxonomic status.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".