First Report of Pierce's Disease of Grape Caused by <i>Xylella fastidiosa</i> in Oklahoma
Notice bibliographique
Résumé
Bacterial leaf scorch caused by the bacterium Xylella fastidiosa was first identified in Oklahoma in American elm (Ulmus americanus L.) in the summer of 2004 (2). Subsequently, additional infections of other shade trees and ornamentals including oak (Quercus spp.), mulberry tree (Morus spp.), and sycamore (Platanus occidentalis) have been identified through sample submission to the Oklahoma State University, Plant Disease and Insect Diagnostic Laboratory. As of July 2008, no grape (Vitis spp.) samples positive for infection by X. fastidiosa were identified in Oklahoma. In August of 2008, leaves of four grape vines (Vitis labrusca 'Concord') grown in a home gardener's backyard located in Canadian County, OK were found to be exhibiting chlorosis and green fading colors with marginal browning. These symptoms included an undulating appearance with red-brown bands between the green and scorched areas. Vines exhibited 'matchstick' symptoms where the leaves dropped from the plant, but the petioles remained attached. All symptoms were consistent with those of Pierce's disease (3). Leaves from all four symptomatic vines and leaves from asymptomatic grapes (V. vinifera, unknown cultivar) from the Oklahoma Botanical Gardens located at Oklahoma State University, Stillwater were sampled. Genomic DNA was extracted from all samples with the DNeasy Plant Mini Kit (Qiagen, Germantown, MD). Samples were tested for the presence of X. fastidiosa by real-time PCR with Xylella genus-specific primers XfF1/XfR2 and dual-labeled TaqMan probe XfP2 (4). Infected tissue from a symptomatic oak tree was used as a positive control. Genomic DNA samples extracted from all four symptomatic grape vines and the symptomatic oak tree were PCR positive. Samples from the asymptomatic grape vine were PCR negative. Subsequent analysis was performed on the four symptomatic grape vine samples. X. fastidiosa-specific primers BBXFOUTF1 and BBXFOUTR1 were used to PCR amplify the gyrB gene (2). The amplification product was purified with the QuickClean 5M PCR Purification Kit (GenScript Corporation, Piscataway, NJ) and was subjected to automated sequencing (Oklahoma State University Recombinant DNA/Protein Resource Facility). BLASTN alignment (1) of the 340-bp sequences from the four symptomatic grape samples revealed 99 to 100% homology with the gyrB gene from a Pierce's disease strain of X. fastidiosa, 'Temecula' (GenBank No. AF534960). Remaining petiole tissues from the samples used above were subjected to serological tests for X. fastidiosa by ELISA (Agdia, Inc. Elkhart, IN). These tests confirmed the presence of X. fastidiosa in symptomatic grape tissue. To our knowledge, this is the first report of X. fastidiosa associated with grape and the first report of Pierce's disease in Oklahoma. This suggests that the geographic range for Pierce's disease should be extended to include central Oklahoma. References: (1) S. F. Altschul et al. J. Mol. Biol. 215:403, 1990. (2) B. R. Olson et al. Plant Dis. 90:108, 2006. (3) R. C. Pearson et al. Compendium of Grape Diseases. The American Phytopathological Society, St. Paul, MN, 1998. (4) N. W. Schaad et al. Phytopathology 92:721, 2002.
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 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,002 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 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 ».