Management of phytophthora blight (<i>Phytophthora capsici</i>) on vegetables in Ontario: some greenhouse and field aspects
Bibliographic record
Abstract
Phytophthora blight (Phytophthora capsici) affecting greenhouse vegetable production in Canada is reported for the first time. Aspects of the epidemiology and management of P. capsici in relation to greenhouse and field vegetable production in Ontario are discussed. Identification of the pathogen was based on cultural, morphological and molecular approaches, the latter using primer set PC1/2. The pathogen caused 10% plant population losses in a greenhouse pepper operation in Leamington, ON in 2006–2007, and 5%, 5% and 10% losses in commercial greenhouse tomato operations at sites in 2007, 2008 and 2011, respectively, with 1000 greenhouse tomato plants affected in 2012. Phytophthora blight occurred in 2006 in Haldimand-Norfolk and Essex counties on field cucumber and pepper, respectively, and in Essex county in 2007 on field pepper, squash and tomato. The disease was not observed on field pepper, tomato or cucumber plants in fungicide efficacy trials near Harrow, ON in 2005–2006 or near St. Williams, ON in 2007 where the disease had occurred previously. Symptom development was most rapid on greenhouse cucumber and least rapid on greenhouse tomato. Virkon® disinfectant at 0.25%, 0.5%, 1% and 2% commercially formulated product was 100% effective in preventing zoospore germination of P. capsici while Chemprocide™ disinfectant was not fully effective at 0.04%, 0.4% and 4%, and Virucidal Extra® was intermediate in efficacy. The fungicides fluazinam, mandipropamid, cyazofamid and fluopicolide were effective in controlling P. capsici on greenhouse tomato, cucumber, and pepper plants for at least a 14-day period. Metalaxyl was less effective, possibly due to partial resistance in the fungus to this chemical.
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 | 0.000 | 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 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".