Genetic characterization of strains named as <i>Xanthomonas axonopodis</i> pv. <i>dieffenbachiae</i> leads to a taxonomic revision of the <i>X. axonopodis</i> species complex
Bibliographic record
Abstract
Xanthomonas axonopodis pv. dieffenbachiae (Xad) is the causal agent of anthurium bacterial blight and listed as an A2 quarantine organism by EPPO. However, the name Xad covers a variety of strains. Here, 25 Xad strains and 88 phylogenetically related strains, including Xanthomonas type strains and representatives of other pathovars, were examined using a polyphasic taxonomic approach. Multilocus sequence analysis of seven genes showed that strains isolated from Dieffenbachia , Philodendron and Anthurium cluster into three phylogenetic groups (PG I, II and III), while the type strain of X. axonopodis clustered into a fourth group (PG IV). PG I included the type strains of X. citri subsp. citri , X. citri subsp. malvacearum , X. fuscans subsp. fuscans and X. fuscans subsp. aurantifolii . PG II included the type strains of X. euvesicatoria , X. perforans , X. alfalfae subsp. alfalfae and X. alfalfae subsp. citrumelonis . PG III included the type strains of X. phaseoli . Each PG was shown to represent a single species, based on average nucleotide identity values, DNA–DNA hybridization data and phenotypic characteristics. Therefore, strains named as Xad belong to PG I, PG II and PG III, and not to X. axonopodis (PG IV). Taxonomic proposals are made: emendations of the descriptions of X. citri , X. phaseoli and X. axonopodis , to encompass the strains of PG I, PG III and PG IV, respectively; and reclassification of X. perforans and X. alfalfae as X. euvesicatoria and emendation of the description of X. euvesicatoria to encompass all strains of PG II.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 |
| Science and technology studies | 0.000 | 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) | 0.001 | 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".