Canadian Journal of Plant Pathology最新文献

{"title":"Comparative proteomic analysis of the moderately resistant and susceptible peanut cultivars during infestation by <i>Cylindrocladium parasiticum</i>","authors":"Xinyu Chen, Mei Luo, Meimei Xiang, Lina Xiong, Yongxin Shu, Guohui Yu, Zhangyong Dong, Yunhao Sun","doi":"10.1080/07060661.2023.2274327","DOIUrl":"https://doi.org/10.1080/07060661.2023.2274327","url":null,"abstract":"AbstractCylindrocladium parasiticum Crous, Wingfield & Alfenas, the causal agent of Cylindrocladium black rot of peanut, has led to economic losses in China. However, the response of peanut plant to C. parasiticum is poorly understood. Here, two contrasting peanut cultivars, T09 (C. parasiticum-moderately resistant) and P562 (C. parasiticum-susceptible) were used for comparative analysis of protein profiles in root segment of plant tissues in responses to C. parasiticum infection. Proteomic profiling identified 1647 and 391 differentially accumulated proteins (DAPs) in P562 and T09 relative to uninoculated control, respectively. A total of 350 and 1095 DAPs were identified between P562 and T09 after 9 day(s) post infection (dpi), respectively. Functional categorization showed that C. parasiticum-responsive proteins were mainly involved in catalytic activity and binding functions. KEGG pathway analysis indicated both moderately resistant and susceptible peanut cultivars can regulate gene expression in the phenylpropanoid pathway, terpenoid backbone biosynthesis, SA, and JA pathways to induce defensive genes and protein expression which enhances plant defence or susceptibility capacity. However, MAPK signal pathway was more pronounced in moderately resistant peanut cultivar T09. We also observed an increase of CYP73A100 involved in phenylpropanoid and flavonoid biosynthesis pathways in susceptible peanut ecotype P562, while decrease in moderately resistant interaction. Additionally, there was a marked activation of brassinosteroid biosynthesis in T09, which indicated a possible involvement of activation of plant immune response in moderately resistant responses of peanut to C. parasiticum. This study provides some insights into molecular networks involved in cellular and physiological responses to C. parasiticum in peanut.RésuméCylindrocladium parasiticum Crous, Wingfield & Alfenas, l’agent causal de la pourriture noire à Cylindrocladium de l’arachide (Arachis hypogaea), est un champignon qui infecte les racines, causant ainsi d’importantes pertes économiques en Chine, aux États-Unis et ailleurs dans le monde. Toutefois, les réactions physiologiques et biochimiques des plants d’arachides à C. parasiticum sont mal comprises. Nous avons étudié, dans le cadre de cette recherche, deux cultivars de plants d’arachides dont la sensibilité à l’infection causée par C.parasiticum varie, T09 (modérément résistant) et P562 (sensible), en nous basant sur l’analyse protéomique comparative de segments de racines à la suite de l’infection provoquée par C. parasiticum. Nous avons identifié 1 647 et 391 protéines différentiellement abondantes (PDA) chez les plants infectés de P562 et de T09, respectivement, comparativement aux plants témoins non inoculés. Nous avons également identifié 350 et 1 095 PDA chez les plants inoculés et non inoculés de P562 et de T09, et ce, 9 jours après l’infection. La catégorisation fonctionnelle des PDA a montré que les protéines sensi","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134954476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Onion leaf blight caused by <i>Alternaria alternata sensu lato</i> and <i>Stemphylium vesicarium</i> in Michoacán, México","authors":"Alfredo Reyes-Tena, Amelia Cristina Montoya-Martínez, Sylvia Patricia Fernández-Pavía, Ricardo Santillán-Mendoza, Adanely Jiménez-Villegas, Daniela Pineda-Vaca, Gerardo Rodríguez-Alvarado","doi":"10.1080/07060661.2023.2277819","DOIUrl":"https://doi.org/10.1080/07060661.2023.2277819","url":null,"abstract":"AbstractMéxico is among the main producers of onions, which are cultivated mainly in the states of Baja California, Chihuahua, Guanajuato, Michoacán, and Zacatecas. During June and November 2017, foliar blight symptoms were observed in commercial onion crops in the municipality of Copándaro, Michoacán. The incidence of the disease was 20% in June and 80% in November. The objective of this work was to identify the causal agent or agents of this disease. Fungal isolates recovered from symptomatic plants presented conidia typical of Alternaria and Stemphylium. Molecular identification and phylogenetic analysis using partial sequences of the nuclear ribosomal internal transcribed spacer (ITS) region, the translation elongation factor-1 alpha (TEF1), and RNA polymerase subunit II (RPB2) genes confirmed the identity of the isolates as species within the Alternaria alternata species complex, and Stemphylium vesicarium. The isolates reproduced foliar blight symptoms in inoculated onion plants in pathogenicity tests. This is the first report of Alternaria alternata sensu lato and Stemphylium vesicarium causing foliar blight in commercial onion crops in Michoacán.Le Mexique est un des principaux producteurs d’oignons, ceux-ci étant cultivés dans les États de Basse-Californie, de Chihuahua, de Guanajuato, de Michoacán et de Zacatecas. Au cours de juin et de novembre 2017, des symptômes de brûlure helminthosporienne ont été observés dans les cultures commerciales de la municipalité de Copándaro, dans le Michoacán. L’incidence de la maladie était de 20 % en juin et de 80 % en novembre. Le but de cette étude était d’identifier l’agent ou les agents causaux de cette maladie. Des isolats fongiques provenant de plants symptomatiques comportaient les conidies typiques d’Alternaria et de Stemphylium. L’identification moléculaire et l’analyse phylogénétique basée sur des séquences partielles de la région de l’espaceur transcrit interne (ITS) de l’ADN ribosomique nucléaire, le facteur d’élongation de la traduction-1 alpha (TEF1) et les gènes de la sous-unité II de l’ARN polymérase (RPB2) ont confirmé l’identité des isolats en tant qu’espèces du complexe Alternaria alternata et Stemphylium vesicarium. Les isolats ont reproduit les symptômes de la brûlure helminthosporienne chez les plants d’oignons inoculés dans le cadre de tests de pathogénicité. Il s’agit de la première mention d’Alternaria alternata et de Stemphylium vesicarium causant la brûlure helminthosporienne dans des cultures commerciales d’oignons au Michoacán.Keywords: Allium cepaKoch’s postulatesleaf blightmultilocus phylogenypathogenicityKEYWORDS: Mots clésAllium cepabrûlure helminthosporiennepathogénicitéphylogénie multilocuspostulats de KochDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR)","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135819604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of Puccinia gibberosa on blue oatgrass (Helictotrichon sempervirens) in Canada, with taxonomic revision of the rust species","authors":"Mehrdad Abbasi, Sarah Hambleton, Miao Liu, Scott A. Redhead, Gurcharn Singh Brar","doi":"10.1080/07060661.2023.2270941","DOIUrl":"https://doi.org/10.1080/07060661.2023.2270941","url":null,"abstract":"AbstractHelictotrichon sempervirens (blue oatgrass) is a perennial grass widely grown for ornamental use in Canada. Rusted blue oatgrass plants with diseased leaves covered with uredinia were collected from two locations at metropolitan Vancouver, British Columbia (BC), in summer 2022. The rust fungus was identified as Puccinia gibberosa (= P. coronata var. gibberosa) based on combined results of morphological characteristics and molecular analyses. The internal transcribed spacer two (ITS2) and partial large subunit ribosomal DNA were amplified and sequenced. The sequence obtained for the rust fungus showed 99.9% identity with the previously reported P. coronata var. gibberosa from USA. This is the first report of rust caused by P. gibberosa on blue oatgrass in Canada. Evidence from phylogenetic analyses supports the recognition of this rust at the species level. A revised description for P. gibberosa is provided, including synonyms, host range and distribution across the globe, and incorporating comprehensive molecular and morphological results for several North American and European specimens. In addition, a lectotype and an epitype are designated here for the rust species.Helictotrichon sempervirens (avoine sempervirente) est une graminée vivace cultivée couramment à des fins ornementales au Canada. À l’été 2022, des plants d’avoine sempervirente rouillée dont les feuilles infectées étaient couvertes d’urédosores ont été collectés à deux endroits de la région métropolitaine de Vancouver, en Colombie-Britannique. Le champignon de la rouille a été identifié en tant que Puccinia gibberosa (= P. coronata var. gibberosa), en se basant sur les résultats combinés des analyses des caractéristiques morphologiques et moléculaires. L’espaceur transcrit interne 2 (ITS2) et la grande sous-unité partielle de l’ADN ribosomique ont été amplifiés et séquencés. La séquence obtenue pour le champignon de la rouille était identique à 99,9 % à P. coronata var. gibberosa préalablement rapporté aux États-Unis. Il s’agit de la première mention de rouille causée par P. gibberosa chez l’avoine sempervirente au Canada. L’indice obtenu des analyses phylogénétiques soutient la reconnaissance de cette rouille au niveau de l’espèce. Une description révisée de P. gibberosa est fournie, y compris les synonymes, la gamme d’hôtes ainsi que l’aire de distribution mondiale, et comprend les résultats détaillés des analyses moléculaires et morphologiques pour plusieurs spécimens nord-américains et européens. En outre, un lectotype et un épitype ont été sélectionnés pour l’espèce de rouille.Keywords: British Columbiafungal diseasePoaceaePuccinialesrust fungiKEYWORDS: champignons de la rouilleColombie-Britanniquemaladie fongiquepoacéesPuccinialesDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136112489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of <i>Melampsora ferrinii</i> (pucciniales) on Babylon willow ( <i>Salix babylonica</i> ) in Iran","authors":"Mehrdad Abbasi, Gurcharn Singh Brar, M. Catherine Aime","doi":"10.1080/07060661.2023.2266405","DOIUrl":"https://doi.org/10.1080/07060661.2023.2266405","url":null,"abstract":"AbstractAs an agroforestry resource willow species (Salix spp.) becoming increasingly important in the protection of riverbanks, recovery of floodable lands, soil bioremediation, biomass production, and wicker furniture manufacture, Babylon willow (Salix babylonica) is widely planted all over the world and is found throughout Iran as part of the rural landscape and is mostly planted for ornamental or bioremediation purposes. Rust fungi in the genus Melampsora usually cause disease on Salix species. Identification of Melampsora species is often complicated because there are few differences in spore morphology and little publicly available comparative sequence data. Willow trees in Iran have been reported to be infected by 15 Melampsora species; however, most of these records are based on morphological characterization. During surveillance activities carried out in June 2007, a rust species was detected on isolated Babylon willow trees in an area in Northern Iran. Both the rust fungus and the host plant were identified on the basis of morphological features and DNA sequencing. Based on a combination of morphology, large subunit (LSU) rDNA sequencing and phylogenetic analyses, our rust specimen was identified as Melampsora ferrinii, which is newly reported from Iran on Salix babylonica. Melampsora ferrinii was originally described from the Americas and this is the first time this rust has been observed on its telial host, Babylon willow, in Asia. The documentation of the rust fungus was performed using both scanning electron microscopy (SEM) and light microscopy. Additionally, an identification key for Melampsora species reported on Salix spp. in Iran is included.En tant que ressource agroforestière, les espèces de saules (Salix spp.) deviennent de plus en plus importantes dans la protection des berges, la récupération des terres inondables, la bioremédiation des sols, la production de biomasse et la fabrication de meubles en osier. Le saule de Babylone (Salix babylonica) est largement planté dans le monde entier et se trouve dans tout l’Iran dans le cadre du paysage rural principalement planté à des fins ornementales ou de bioremédiation. Les champignons de la rouille du genre Melampsora provoquent généralement des maladies sur les espèces de Salix. L’identification des espèces de Melampsora est souvent compliquée en raison du peu de différences dans la morphologie des spores et du peu de données de séquence comparative accessibles au public. Des saules en Iran ont été signalés comme étant infectés par 15 espèces de Melampsora, cependant, la plupart de ces signalements sont basés sur la caractérisation morphologique. Au cours des activités de surveillance menées en juin 2007, une espèce de rouille a été détectée sur des arbres isolés de saule de Babylone dans une zone située au nord de l’Iran. Le champignon de la rouille et la plante hôte ont été identifiés sur la base des caractéristiques morphologiques et du séquençage de l’ADN. Sur la base de la","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inheritance of Fusarium wilt resistance in flax","authors":"Priyangi Edirisinghe, Lipu Wang, Lester Young, Helen Booker, Khalid Rashid, Hadley Kutcher","doi":"10.1080/07060661.2023.2265900","DOIUrl":"https://doi.org/10.1080/07060661.2023.2265900","url":null,"abstract":"AbstractFusarium wilt (FW) caused by the facultative fungal saprophyte Fusarium oxysporum f. sp. lini (Fol) is a major disease affecting flax production. Cultivation of FW-resistant cultivars mitigate effects of the disease and are a requirement for variety registration. Understanding the genetic inheritance of FW resistance will facilitate the development of resistant varieties. In this study, the inheritance of wilt resistance against western Canadian isolates was studied in F8 recombinant inbred lines (RILs) of a cross between cultivars Aurore (moderately resistant) and Oliver (susceptible). Seventeen Fol isolates were collected from across western Canada and tested for differences in the severity of FW on both parental lines and two check lines under controlled environment conditions. Three of the 17 isolates that caused moderate disease severity were selected to screen the RIL population. The segregation of the RILs for FW resistance was determined under controlled conditions and in field wilt nurseries. A 3:1 ratio of susceptible to resistant RILs was observed with two F. oxysporum f. sp. lini isolates, indicating FW resistance was conditioned by two independent recessive genes. Cluster analysis of disease severity data identified two major clusters of phenotypes in the RIL population, in accordance with the 3S:1 R ratio. High heritability of FW resistance was observed at the late flowering stage, indicating a high level of genotypic variation contributing to phenotypic variation.La fusariose, causée par le saprophyte facultatif fongique Fusarium oxysporum f. sp. lini (Fol), est une importante maladie qui nuit à la production de lin. La culture de cultivars résistants à la fusariose atténue les effets de la maladie et est une exigence quant à l’homologation des variétés. La compréhension de l’héritage génétique de la résistance à la fusariose facilitera la mise au point de variétés résistantes. Dans cette étude, l’héritage de la résistance à la flétrissure à l’égard d’isolats de l’Ouest canadien a été examiné dans des lignées endogames recombinantes F8 (LER) issues d’un croisement entre les cultivars Aurore (modérément résistant [rés.]) et Oliver (réceptif [réc.]). Dix-sept isolats de Fol ont été collectés dans tout l’Ouest canadien et testés en fonction de leurs différences relatives à la gravité de la fusariose chez les deux lignées parentales et deux lignées de validation dans des conditions contrôlées. Trois des dix-sept isolats qui ont causé une maladie de gravité modérée ont été sélectionnés pour cribler la population de LER. La ségrégation de LER en vue de la résistance à la fusariose a été déterminée dans des conditions contrôlées et dans des pépinières à fusariose en plein champ. Un rapport de 3:1 de LER réceptives à résistantes a été observé avec deux isolats de Fusarium oxysporum f. sp. lini, indiquant que la résistance à la fusariose dépendait de deux gènes récessifs indépendants. L’analyse typologique des données relatives à la","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135895224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial consortia as an option for biocontrol of <i>Stromatinia cepivora</i>","authors":"Christian David Vargas Baquero, Alba Marina Cotes","doi":"10.1080/07060661.2023.2262959","DOIUrl":"https://doi.org/10.1080/07060661.2023.2262959","url":null,"abstract":"AbstractStromatinia cepivora, the causal agent of white rot, is responsible for 60-80% of economic losses in onion and garlic crops. This work aimed to select biological control agents (BCAs) to control white rot. Ten microorganisms were tested for hyperparasitic activity on S. cepivora sclerotia in garlic (Allium sativum). Bioassays consisted of pots filled with sterile soil and 50 sclerotia in a plastic Tulle bag. Four microorganisms were selected to compare their capability for degrade sclerotia on garlic. Our results showed that increasing degradation happened when Th034, Th035, Th003 and Bs006 were added to the pots containing garlic. Subsequently, three application techniques (seeds, seedlings at transplant, and seeds and transplant) were evaluated. Seven BCAs applied singly and in mixtures were evaluated in semi-field experiments for their ability to reduce white rot symptoms in onion plants in soil inoculated with 300 sclerotia per kilogram. The results indicated that efficacy was dependent on microrganism, mixture, and technique of application. The synergy factor showed that only two treatments have synergistic effects. In both cases, the mixture consisted of a strain of Bacillus and two species of Trichoderma (T. koningiopsis, T. atroviride) applied twice. In most cases, antagonistic interactions among BCAs were observed.Stromatinia cepivora, l’agent causal de la pourriture blanche, est responsable de 60 à 80 % des pertes financières relatives à la culture de l’oignon et de l’ail. Ces travaux visent à sélectionner des agents de lutte biologique (ALB) pour combattre la pourriture blanche. Dix microorganismes ont été testés pour leur activité hyperparasitique envers les sclérotes de S. cepivora chez l’ail (Allium sativum). Des biotests consistaient à placer dans des pots du sol stérile et 50 sclérotes contenus dans des sachets en tulle de plastique. Quatre microorganismes ont été sélectionnés afin de comparer leur capacité à dégrader les sclérotes sur l’ail. Nos résultats ont montré que davantage de dégradation se produisait lorsque Th034, Th035, Th003 et Bs006 étaient ajoutés aux pots contenant l’ail. Subséquemment, trois techniques d’application ont été évaluées (semences, plantules lors de la transplantation et semences et transplantation). Sept ALB appliqués seuls ou combinés ont été évalués au cours d’expériences menées dans des conditions semi-naturelles en vue de déterminer leur capacité à réduire les symptômes de la pourriture blanche chez l’oignon dans un sol inoculé avec 300 sclérotes par kilogramme. Les résultats ont indiqué que l’efficacité dépendait du microorganisme, de la combinaison et de la technique d’application. Le facteur de synergie a démontré que seuls deux traitements ont des effets synergiques. Dans les deux cas, la combinaison consistait en une souche de bacilles et deux espèces de Trichoderma (T. koningiopsis, T. atroviride) appliquées à deux reprises. Dans la plupart des cas, des interactions antagonistes entre","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biosurveillance of oak wilt disease in Canadian areas at risk","authors":"Marie-Krystel Gauthier, Émilie Bourgault, Amélie Potvin, Guillaume J. Bilodeau, Sven Gustavsson, Sharon Reed, Pierre Therrien, Évelyne Barrette, Philippe Tanguay","doi":"10.1080/07060661.2023.2261890","DOIUrl":"https://doi.org/10.1080/07060661.2023.2261890","url":null,"abstract":"Biosurveillance of invasive species is critical for protecting native ecosystems and limiting economic losses. Early detection of pathogens through qPCR methods has recently shown great promise and can potentially slow the spread of devastating diseases. For instance, oak wilt, a disease caused by the fungus Bretziella fagacearum, can kill mature trees within weeks of infection. Originally contained in the United States, oak wilt has finally made its way into Canada, where it was recently observed for the first time in June 2023. This study has laid the foundations for a biosurveillance monitoring program of B. fagacearum in Eastern Canada. From 2019 to 2021, insect vectors were baited and captured in Lindgren traps in various locations of interest, namely sawmills importing oak logs from the United States (US), forested areas containing mature oak trees and strategic sites along the border between the two countries. Insect vectors and collection fluids were analysed with our qPCR detection test for the presence of B. fagacearum. As a positive control to validate this method, we included traps in a known centre of oak wilt infection in Michigan (US). Our analysis showed only one positive site at the border between Ontario (CA) and the US, even though oak wilt has never been observed there. This result confirms that DNA from B. fagacearum can be detected with this method even before the appearance of symptomatic trees, which could be crucial in the current containment efforts in Ontario (CA).","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135539146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erysiphe thuemenii causing powdery mildew on Potentilla indica in China","authors":"Qinen He, L. Bai, Fang Cai","doi":"10.1080/07060661.2023.2253774","DOIUrl":"https://doi.org/10.1080/07060661.2023.2253774","url":null,"abstract":"Abstract In August 2017, severe powdery mildew was observed on Potentilla indica in Minhe, Qinghai province, China. The identification of fungal species was performed by morphological study using an optical microscope and scanning electron microscope (SEM), supplemented by sequence analysis of the internal transcribed spacer (ITS) region of rDNA. Based on a combination of morphology, ITS sequence, and host, the powdery mildew on Potentilla indica was identified as Erysiphe thuemenii, a species belonging to the E. aquilegiae complex. This is the first report of E. thuemenii causing powdery mildew on a new host species, P. indica, in China and also worldwide.","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44515703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Canadian Plant Disease Survey 2023 Volume 103: Disease Highlights 2022","authors":"J. Elmhirst","doi":"10.1080/07060661.2023.2222486","DOIUrl":"https://doi.org/10.1080/07060661.2023.2222486","url":null,"abstract":"","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44081302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crown gall development on cannabis (Cannabis sativa L., marijuana) plants caused by Agrobacterium tumefaciens species-complex","authors":"J. Holmes, H. Sanghera, Z. Punja","doi":"10.1080/07060661.2023.2224776","DOIUrl":"https://doi.org/10.1080/07060661.2023.2224776","url":null,"abstract":"Abstract Crown gall, caused by Agrobacterium tumefaciens (syn. Rhizobium radiobacter), is characterized by gall formation on crowns, stems or roots on many plant species. We describe the occurrence of this disease for the first time on cannabis (Cannabis sativa L. marijuana) plants in two licenced production facilities in British Columbia. Galls were observed on crowns, stems and roots of several genotypes, including ‘White Rhino’, ‘Pink Kush’ and ‘Sour Kush’. The affected plants displayed no other visible symptoms. The incidence of crown gall was extremely low, estimated at 0.01% of total plants. Isolations made from root and stem galls on MacConkey medium (selective for Gram -ve bacteria) and on D1 medium (selective for Agrobacterium spp.) yielded a range of bacterial species, which did not include Agrobacterium sp. However, the presence of Agrobacterium in gall tissues was confirmed following PCR amplification with primers for the indole-acetic acid (iaa) H gene on the T-DNA region of Agrobacterium spp. and showed > 99% similarity to A. tumefaciens. Artificial inoculations were conducted using an A. tumefaciens strain from ATCC (Rhizobium radiobacter, strain designation TT134 [6-1-2, CIP 104 336], cat. 15955) which resulted in gall formation on five cannabis genotypes tested. These galls contained the iaaH gene as determined by PCR and the pathogen was successfully re-isolated on MacConkey agar medium at 4 and 10 weeks post-inoculation. Our findings confirm the occurrence of A. tumefaciens on naturally infected and artificially infected cannabis plants grown under greenhouse conditions and demonstrate reproducible gall symptoms on several cannabis genotypes following A. tumefaciens inoculation.","PeriodicalId":9468,"journal":{"name":"Canadian Journal of Plant Pathology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45981751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}