Potential loss of clubroot resistance genes from donor parent <i>Brassica rapa</i> subsp. <i>rapifera</i> ( <scp>ECD</scp> 04) during doubled haploid production
Bibliographic record
Abstract
Clubroot resistance derived from the oilseed rape/canola Brassica napus ‘Mendel’ has been overcome in some fields in Alberta, Canada, by the emergence of ‘new’ strains of the protist Plasmodiophora brassicae . Resistance to the pathogen was assessed in 112 doubled haploid ( DH ) lines, derived from B. rapa subsp. rapifera (European clubroot differential ( ECD ) 04). The lines were evaluated against five single‐spore isolates representing the ‘old’ pathotypes 2, 3, 5, 6 and 8, and 15 field populations representing new strains of P. brassicae . The disease severity index ( ID %) data revealed that none of the DH lines were resistant or moderately resistant to the new pathotype 5X (field populations L‐G1, L‐G2, L‐G3) and D‐G3, while 3–42% were resistant or moderately resistant to the other 11 new strains. Using the mean ID induced by the old pathotype 3 (approx. 13.5%) as the baseline, clubroot severity increased by 300–600% when inoculated with the new pathotypes. A significant finding of this study was the fact that ECD 04 showed absolute resistance to all of the old and new P. brassicae strains while the B. napus ‘Mendel’, although resistant to all of the old pathotypes, was resistant to only about 50% of the new strains. Similarly, all of the selected clubroot‐resistant commercial canola cultivars evaluated in this study were susceptible to 87% of the new P. brassicae strains. The molecular data revealed that the breakdown of clubroot resistance in Mendel and the canola cultivars was in part due to the non‐inheritance of the Crr1 gene on the A08 chromosome from ECD 04.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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 teacher head, 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".