Pathogenic variation of<i>Verticillium dahliae</i>after serial passages through potato and sunflower
Bibliographic record
Abstract
Verticillium wilt is a limiting factor in many field crops, including potato and sunflower. The causal agent, Verticillium dahliae Kleb., is known for its high level of diversity and pathogenic variability. In an earlier study, we showed such a high variability among isolates recovered from either potato or sunflower when inoculated on their original or alternative hosts. Verticillium dahliae isolates from potato were more aggressive on both potato and sunflower while the ones from sunflower were to a certain extent more adapted to sunflower than to potato. In the present study, we show the ability of weakly aggressive potato isolates to gain pathogenicity on either potato or sunflower when inoculated to a susceptible potato cultivar ‘Kennebec’ for four successive generations. However, some isolates showed a loss in pathogenicity after four successive passages on susceptible potato cultivar ‘Kennebec’, especially on the moderately resistant potato cultivar ‘Ranger Russet’. Results in terms of gain or loss of pathogenicity by potato and sunflower isolates are discussed in relation to the effect of successive passages through their original or alternative hosts. Key words: Verticillium dahliae Kleb., potato, sunflower, host of origin, alternative host, successive passages, pathogenicity gain/loss, pathogenicity index. La verticilliose constitue un facteur limitant pour de nombreuses cultures incluant la pomme de terre et le tournesol. L’agent causal, Verticillium dahliae Kleb., est connu pour son degré élevé de diversité génétique et de variabilité de pouvoir pathogène. Dans une étude précédente, nous avions montré la présence d’une telle variabilité entre des souches isolées soit de pomme de terre soit de tournesol, et inoculées sur leur hôte d’origine ou alternatif. Les isolats de V. dahliae provenant de pomme de terre étaient plus agressifs aussi bien sur pomme de terre que sur tournesol, tandis que ceux provenant de tournesol étaient relativement mieux adaptés sur tournesol que sur pomme de terre. Dans la présente étude, nous montrons la capacité de certains isolats peu agressifs, provenant de pomme de terre, d’acquérir un plus grand pouvoir pathogène, aussi bien sur pomme de terre que sur tournesol, après avoir été propagés pendant quatre générations sur le cultivar sensible de pomme de terre ‘Kennebec’. Par contre, après quatre passages successifs sur le cultivar ‘Kennebec’, certains isolats ont vu leur pouvoir pathogène diminuer, plus particulièrement sur le cultivar partiellement résistant ‘Ranger Russet’. Ces résultats sont discutés en termes de gain ou de perte de pouvoir pathogène, par des isolats provenant de pomme de terre ou de tournesol, dans le but d’élucider l’effet de leur passages successifs sur leurs hôtes d’origine ou alternatif. Mots-clés : Verticillium dahliae Kleb., pomme de terre, tournesol, hôte d’origine, hôte alternatif, passages successifs, gain/perte de pouvoir pathogène, index de pathogenicité.
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 | 0.000 | 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 | 0.001 |
| 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".