Modeling blackleg severity and incidence in canola and identification of molecular markers linked to a Leptosphaeria maculans avirulence gene
Notice bibliographique
Résumé
Canola is the most important oilseed crop in Canad,a.Blackleg caused by Leptosphøeria maculans is the rnost important disease in canola in the prairie provinces.While the sexual spores have been implicated as primary inoculum, there has not much work done on the asexual pycnidiospores and their role in primary infection in Canada.With the frnding of new blackleg pathogenicity groups in the prairies, there has been renewed interest in understanding the host-pathogen interactions, and the role of R-genes and corresponding avirulence genes in the pathogen.Therefore, the two main goals of the epidemiolo gy part of this study were to investigate the role of pycnidiospores of Leptosphaeria maculans ondisease development on plants infected at the cotyledon (i.0), 3-leaf (1, 03) and 6-leaf (1, 06) stages of Brassica napus cvs.Westar and Q2 under field conditions and to develop nonlinear weather-based models to describe blackleg severity and incidence of the infected plants.The results suggested that pycnidiospores were a source of primary inoculum for 2004 and 2005.The results showed that the mean blackleg severity of the plants infected at the cotyledon stage was significantly higher than plants infected at the other two stages.These results also confirmed that the mean blackleg severity of the plants infected at the 3-leaf stage was higher than plants infected at the 6-leaf stage.Blackleg incidence in the plants infected at the cotyledon stage was significantly higher than the other two stages.No signifìcant difference in disease incidence was observed between the plants infected al3-leaf and 6-leaf stage.Pearson's correlation coefficient showed that two weather variables, total rainfall per week (R) and average maximum temperature per week (Tmøx), werc significantly An atternpt was also made to develop molecular markers for the corresponding avirulence gene in L. mqculans to the LepRI resistance gene in B. napus, and to obtain fuither evidence of a gene-for-gene interaction.The segregation of 94 F1 progen! of Z.maculans from a cross of avirulent isolate (99-56) and virulent isolate (g7-41) on the monogenic line ddm-126s-1 containing LepRI was studied.The progenies were isolated and phenotyped for reactions on the line ddm-1 26s-1.The population segregated in 1 :1 ratio,44 avirulent and 50 virurent d : 0.79, p :0.66), indicating single gene contror of 99-56 avirulence on dm-726s-1.Bulked segregant analysis was used to identiflz two IV Sequence-related amplified polymorphic (SRAP) markers closely linked to the avirulence gene.We have named this avirulence gene AvrLepRI.Two flanking SRAP markers, SA7-108 and SA7-490, were linked to AvrLepRI at 9.6 and 7.8 cM, respectively.This work present further evidence for a gene-for-gene rnodel which has been suggested previuosly in this pathosystem and represents an initial step toward map-based cloning of this gene.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,001 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».