ASSESSING DISEASE CONCERNS ON QUINOA AND EVALUATING SOURCES OF DISEASE RESISTANCE IN CHENOPODIUM SPECIES IN NEW ENGLAND
Notice bibliographique
Résumé
Quinoa (Chenopodium quinoa Willd.) is a potential new crop for New England because of its high nutritional qualities and environmental adaptability; however, its susceptibility to disease such as downy mildew, caused by Peronospora variabilis Gaum is a significant obstacle. Downy mildew is a key disease of quinoa causing yield reductions up to 33% in tolerant varieties and 99% yield loss in susceptible varieties. Warm temperatures and high humidity in New England provide optimum conditions for pathogen infection and spread, negatively impacting quinoa growth and yield. This pathogen is able to persist in the seed coat of quinoa and overwinter in soils, making it difficult to manage in a farm setting. These characteristics, as well as reports of fungicide resistance in other downy mildew systems, make genetic resistance the most effective strategy to combat this pathogen. P. variabilis has been reported in North America, specifically in Alberta, Canada and Pennsylvania however it is not known to occur in New England. This research serves as preliminary work for future studies to identify genes contributing to disease resistance in New England native Chenopodium species for future use in breeding programs. The specific objectives of this research were to (1) optimize molecular protocols to detect P. variabilis and confirm the presence of the pathogen in New Hampshire, (2) evaluate differential resistance to downy mildew among Chenopodium accessions, (3) identify other potential pathogens of Chenopodium spp. in New England, and (4) investigate molecular relationships among New England P. variabilis isolates. A molecular pipeline involving touchdown PCR was developed and used to confirm the presence of P. variabilis on Chenopodium species in New Hampshire. Field trials conducted at the UNH Woodman Research Farm evaluated downy mildew disease severity on ten Chenopodium accessions representing four species. Disease severity for each treatment was compared and significant differences were observed among treatments. C. berlandieri var. macrocalycium ecotypes collected from Rye Beach, NH and Appledore Island, ME exhibited the lowest mean disease severity over the season. P. variabilis was isolated from each of the 10 accessions and COX2 sequences were compared; phylogenetic analyses suggest no effect of host species; however, New Hampshire isolates formed a clear cluster when compared with Pennsylvania and South American isolates, suggesting the presence of distinct populations based on geographic location. A second disease causing stem lesion symptoms was observed in the 2018 field trial. Stem lesion incidence was significantly different among Chenopodium accessions, with certain quinoa accessions (37P, QQ065, cultivar Faro) exhibiting low incidence; however, definitive conclusions were not reached in regard to the identity of the stem lesion causal agent. Overall, results from this study provide the first step in identification of potential New England native sources of resistance to downy mildew within the genus, confirmation that downy mildew is present and may be problematic for New England quinoa growers, and documentation of another unknown quinoa pathogen that will need to be managed. These results also provide preliminary information needed to further investigate resistance at the genomic level in Chenopodium spp. and pathogenicity factors in P. variabilis.
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 distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 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 tête enseignante, 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 ».