Detecting<i>Xanthomonas axonopodis</i>pv.<i>manihotis</i>in cassava true seeds by nested polymerase chain reaction assay
Bibliographic record
Abstract
Cassava bacterial blight, caused by Xanthomonas axonopodis pv. manihotis (Xam), is a particularly destructive disease in South America and Africa. Because of quarantine procedures, international exchange of cassava germplasm is limited and occurs through true seeds or material propagated in vitro. The success of a cassava-seed certification program depends on the availability of reliable tests to detect the pathogen in true seeds and vegetative planting materials. We developed a nested polymerase chain reaction assay to detect the pathogen in cassava true seeds. The internal primers directed the amplification of a fragment of 509 base pairs in all 12 Xam strains tested, whereas no amplification product was obtained from any of the 17 strains of other Xanthomonas pathovars tested. Nested polymerase chain reaction worked well for Xam detection from cultured cells from artificially inoculated seeds and naturally infected seeds. The best detection level allowed to detect a presence as low as one to two viable cells per reaction. This technique was specific, sensitive, and rapid for detecting Xam in cassava true seeds.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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) | 0.000 | 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".