Article
Agronomy
M. Harunur Rashid, Sakaria Liban, Xuehua Zhang, Paula Parks, Hossein Borhan, W. G. Dilantha Fernando
Summary: The study found that blackleg incidence was reduced by 40% in 2017 compared to 2014, and disease severity was reduced by 21% to 52% in 2017 compared to 2014, but the impact on R genes Rlm4 and Rlm2 was not significant.
Article
Agronomy
Zhongwei Zou, W. G. Dilantha Fernando
Summary: In this study, a BnNAC19 gene from Brassica napus was identified and characterized. Overexpression of BnNAC19 in transgenic canola plants improved seedling resistance and inhibited the growth and spore production of L. maculans. The transgenic canola plants also showed increased disease resistance in the adult plant stage. The findings suggest that BnNAC19 plays a positive role against L. maculans.
Review
Plant Sciences
M. Hossein Borhan, Angela P. Van de Wouw, Nicholas J. Larkan
Summary: Canola is a significant oilseed crop worldwide, but blackleg disease causes major yield losses. Recent genomic advancements have increased the understanding of the interaction between Brassica napus and Leptosphaeria maculans, making it a model for studying plant-pathogen associations.
ANNUAL REVIEW OF PHYTOPATHOLOGY
(2022)
Article
Plant Sciences
Aldrin Y. Cantila, William J. W. Thomas, Nur Shuhadah Mohd Saad, Anita A. Severn-Ellis, Robyn Anderson, Philipp E. Bayer, David Edwards, Angela P. van de Wouw, Jacqueline Batley
Summary: Utilising resistance genes, such as LepR1, could help manage blackleg disease in canola and increase crop yield. A genome wide association study in canola revealed significant SNPs associated with LepR1 resistance, with the majority located on chromosome A02 and containing multiple resistance gene analogs. This research provides insights into blackleg resistance in canola and aids in the identification of functional LepR1 candidate genes.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Biochemical Research Methods
Wendelin Schnippenkoetter, Mohammad Hoque, Rebecca Maher, Angela Van de Wouw, Phillip Hands, Vivien Rolland, Luke Barrett, Susan Sprague
Summary: Novel methods for assessing variation in quantitative resistance to blackleg disease in canola were developed based on quantifying in planta fungal biomass. The results showed that these methods were accurate, non-subjective, and capable of differentiating fungal biomass in different host-isolate treatments, with the potential for fine-scale blackleg resistance phenotyping in canola.
Article
Plant Sciences
Heting Fu, Yalong Yang, Alian Sarkes, Michael W. Harding, David Feindel, Jie Feng
Summary: Two probe-based qPCR systems, P-Lb and P-Lm, were developed for specific detection of Leptosphaeria biglobosa and L. maculans, the blackleg pathogens of canola. The systems showed species-specificity and broad subspecies-level applicability. Sensitivity tests demonstrated the ability to detect as few as 200 spores of either species. When used in duplex qPCR, the systems yielded similar results as in singleplex qPCR. This study presents the first-reported duplex qPCR protocol for detection and quantification of these blackleg pathogens from field samples.
Review
Agronomy
Ali Zamanmirabadi, Roghayeh Hemmati, Aria Dolatabadian, Jacqueline Batley
Summary: Blackleg, caused by a complex of Leptosphaeria species, poses a serious threat to canola production in Iran, with research lagging behind the rapid spread of the disease. More systematic and prospective studies are needed to develop effective disease management strategies.
Article
Biochemistry & Molecular Biology
Qilin Chen, Gary Peng, Randy Kutcher, Fengqun Yu
Summary: Using whole-genome sequencing, genetic diversity and population structure of Leptosphaeria maculans were revealed, showing two main groups and multiple subgroups. Analysis of nucleotide diversity and differentiation confirmed genetic variation within and among populations.
JOURNAL OF GENETICS AND GENOMICS
(2021)
Review
Biochemistry & Molecular Biology
Aldrin Y. Cantila, Nur Shuhadah Mohd Saad, Junrey C. Amas, David Edwards, Jacqueline Batley
Summary: Canola is the most economically significant Brassica oilseed globally, but its production can be limited by blackleg disease caused by Lepstosphaeria maculans. Research has shown that genetic resistance against blackleg comes in two forms: qualitative resistance mediated by R genes and quantitative resistance.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Agronomy
Seyedmojtaba Mansouripour, Atena Oladzad, Fereshteh Shahoveisi, Md. Mukhlesur Rahman, Luis E. del Rio Mendoza, Sujan Mamidi, Samira Mafi Moghaddam
Summary: The study conducted a genome-wide association study on B. napus accessions to identify genetic regions associated with resistance to blackleg caused by Leptosphaeria maculans. By using multiple arrangements of the same phenotypic dataset, significant markers distributed among different chromosomes were detected, showing the benefit of using different subsets in GWAS. The markers identified in this study could facilitate marker assisted selection for transferring blackleg resistance into modern breeding lines.
EUROPEAN JOURNAL OF PLANT PATHOLOGY
(2021)
Article
Agronomy
M. Harunur Rashid, Sakaria H. Liban, Xuehua Zhang, Paula S. Parks, Hossein Borhan, W. G. Dilantha Fernando
Summary: Blackleg, caused by Leptosphaeria maculans, is a major disease of canola worldwide. Canadian growers have been growing canola more intensively, leading to a reduction in blackleg incidence. The study suggests that canola cultivars with major resistance genes LepR1, LepR3, Rlm2, and Rlm4 remain effective against blackleg in a 2-year rotation.
EUROPEAN JOURNAL OF PLANT PATHOLOGY
(2022)
Article
Agronomy
Angela P. Van de Wouw, Jack L. Scanlan, Hawlader A. Al-Mamun, Marie-Helene Balesdent, Lydia Bousset, Lenka Burketova, Luis del Rio Mendoza, W. G. Dilantha Fernando, Coreen Franke, Barbara J. Howlett, Yong-Ju Huang, E. Eirian Jones, Birger Koopmann, Suhaizan Lob, Ali Z. Mirabadi, Bridgit C. Nugent, Gary Peng, Franco R. Rossi, Huibrecht Schreuder, Annie R. Tabone, Gert J. Van Coller, Jacqueline Batley, Alexander Idnurm
Summary: This study collected isolates of Leptosphaeria maculans and L. biglobosa from different countries to represent the global diversity of these fungal pathogens. The genomes of L. maculans isolates were sequenced, and the distribution and identity of avirulence gene alleles were determined. The study found geographical separation of populations within L. maculans isolates, providing a resource for studying disease-causing mechanisms and discovering new resistance traits.
Article
Genetics & Heredity
Jack L. Scanlan, Angela C. Mitchell, Stephen J. Marcroft, Leanne M. Forsyth, Alexander Idnurm, Angela P. Van de Wouw
Summary: The continued use of fungicides leads to the emergence of strains with reduced sensitivity to the chemicals. A study on canola pathogens in Australia found that resistance to demethylation inhibitor (DMI) fungicides has developed due to DNA insertions in the erg11/CYP51 gene. The research also identified additional insertions using deep amplicon sequencing and showed a correlation between the frequencies of resistant alleles and in planta resistance. This study provides a method for assessing fungicide resistance in plant pathogen populations and implies the potential loss of disease control effectiveness in the field.
FUNGAL GENETICS AND BIOLOGY
(2023)
Article
Agriculture, Multidisciplinary
A. P. Van de Wouw, J. L. Scanlan, S. J. Marcroft, A. J. Smith, E. M. Sheedy, N. W. Perndt, C. E. Harrison, L. M. Forsyth, A. Idnurm
Summary: The use of fungicides is widespread in canola-growing regions of Australia to combat blackleg disease caused by Leptosphaeria maculans. While resistance to demethylation inhibitor (DMI) fungicides is common, there is also evidence of potential cross-resistance to a newer class of fungicides, highlighting the importance of proactive surveillance to maintain fungicide efficacy.
CROP & PASTURE SCIENCE
(2021)
Article
Plant Sciences
Kaluhannadige Rasanie Eranka Padmathilake, Wannakuwattewaduge Gerard Dilantha Fernando
Summary: This study confirmed the effectiveness of L. biglobosa as a biocontrol agent against L. maculans through various methods, and explained its inhibitory mechanism through gene expression analysis.
Article
Plant Sciences
Nicole M. Fox, Sheau-Fang Hwang, Victor P. Manolii, George Turnbull, Stephen E. Strelkov
Summary: Clubroot, caused by Plasmodiophora brassicae, is a significant soilborne disease in canola crops, and the application of hydrated lime may reduce disease severity. Field experiments showed varying efficacy of hydrated lime in reducing disease index in susceptible canola cultivars, while a greenhouse study indicated its potential effectiveness over limestone in managing the pathogen.
CANADIAN JOURNAL OF PLANT PATHOLOGY
(2022)
Article
Plant Sciences
Michael D. Holtz, Sheau-Fang Hwang, V. P. Manolii, Stephen E. Strelkov
Summary: A new strain of Plasmodiophora brassicae, termed '5X', has been discovered in Canada, belonging to a second population of the pathogen. Molecular markers specific for this population have shown its presence in central Alberta, with low levels detected in some galls from 2005 to 2016, and predominant in others. Despite being relatively uncommon, this new population was found to be widespread across different counties in Alberta prior to the release of clubroot-resistant canola varieties.
CANADIAN JOURNAL OF PLANT PATHOLOGY
(2022)
Article
Agronomy
Haitian Yu, Qixing Zhou, Sheau-Fang Hwang, Andrew J. Ho, Kan-Fa Chang, Stephen E. Strelkov, Yuhua He, Robert L. Conner, Michael W. Harding
Summary: Root rot is a common disease in soybean and field pea, which limits crop production in Canada. This study identified different anastomosis groups (AGs) of Rhizoctonia isolates and evaluated their aggressiveness and genetic variability. The results showed no correlation between AGs, locations, aggressiveness, or host origins. Phylogenetic analysis and ISSR markers revealed a high level of genetic diversity among the isolates.
CANADIAN JOURNAL OF PLANT SCIENCE
(2022)
Article
Plant Sciences
Andrea Botero-Ramirez, Sheau-Fang Hwang, Stephen E. Strelkov
Summary: The study evaluated the effect of clubroot disease on canola yield, with results showing that disease severity and incidence increased with higher inoculum concentrations, with susceptible cultivars exhibiting the highest disease levels and resistant cultivars showing lower disease severity. Yield, pods per plant, and 1000-grain weight decreased with increasing disease severity.
CANADIAN JOURNAL OF PLANT PATHOLOGY
(2022)
Article
Plant Sciences
Xitong Liu, Stephen E. Strelkov, Rifei Sun, Sheau-Fang Hwang, Rudolph Fredua-Agyeman, Fei Li, Shifan Zhang, Guoliang Li, Shujiang Zhang, Hui Zhang
Summary: The genetic basis and histopathology of clubroot resistance in two Chinese cabbage inbred lines were evaluated, showing that different resistance genes and infection processes were present.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Plant Sciences
Qinqin Zhou, Kethmi N. Jayawardhane, Stephen E. Strelkov, Sheau-Fang Hwang, Guanqun Chen
Summary: This study identified PLA genes in Arabidopsis that are associated with clubroot resistance. The susceptibility of mutants in Arabidopsis to Plasmodiophora brassicae infection validated the potential utility of these genes. By analyzing transcriptomic datasets from canola infected by P. brassicae, promising candidate genes for further characterization were also identified.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Plant Sciences
Longfei Wu, Rudolph Fredua-Agyeman, Stephen E. Strelkov, Kan-Fa Chang, Sheau-Fang Hwang
Summary: This study aimed to detect quantitative trait loci (QTL) conferring partial resistance to Fusarium root rot and wilting in field pea. The study identified stable QTL and significant digenic epistatic interactions, which are important for breeding disease-resistant pea varieties and developing markers.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Plant Sciences
J. Cui, S. E. Strelkov, R. Fredua-Agyeman, S. F. Hwang
Summary: Verticillium stripe, an emerging soilborne disease of canola in Canada, was studied using improved inoculation techniques. The results showed that the root-dip method had a significant impact on seedling mortality, while the grain inoculation method had a greater effect on adult plant severity. The age of the host plant at inoculation did not significantly affect disease development.
CANADIAN JOURNAL OF PLANT PATHOLOGY
(2023)
Article
Agronomy
Krista A. Zuzak, Stephen E. Strelkov, George D. Turnbull, Victor P. Manolii, Sheau-Fang Hwang
Summary: Clubroot, a damaging disease of canola caused by Plasmodiophora brassicae, can be effectively managed using the soil fumigant Vapam. Replicated experiments showed significant reductions in clubroot severity following treatment with Vapam, and there were residual effects observed in the year following treatment.
CANADIAN JOURNAL OF PLANT SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Longfei Wu, Rudolph Fredua-Agyeman, Stephen E. Strelkov, Kan-Fa Chang, Sheau-Fang Hwang
Summary: In this study, novel genes associated with partial resistance to Aphanomyces root rot in field pea were identified using BSR-seq technology, providing a theoretical basis for the management of this disease.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biochemistry & Molecular Biology
Qinqin Zhou, Leonardo Galindo-Gonzalez, Sheau-Fang Hwang, Stephen E. Strelkov
Summary: The validation of gene expression data from a previous RNA-seq study of clubroot using the NanoString nCounter System shows efficient gene expression quantification. Comparisons with qPCR and RNA-seq demonstrate high correlation in gene expression values, with most genes showing the same expression patterns.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Plant Sciences
Keisha B. Hollman, Victor P. Manolii, Yoann Aigu, Michael W. Harding, Sheau-Fang Hwang, Stephen E. Strelkov
Summary: Clubroot is a significant soilborne disease of canola on the Canadian Prairies. New pathotypes of the causative agent, Plasmodiophora brassicae, have emerged that can overcome the commonly used resistance. Monitoring for pathotypes is crucial for managing resistance.
CANADIAN JOURNAL OF PLANT PATHOLOGY
(2023)
Article
Plant Sciences
Charitha P. A. Jayasinghege, Jocelyn A. Ozga, Victor P. Manolii, Sheau-Fang Hwang, Stephen E. Strelkov, Martin Cerny, Veronika Hyskova
Summary: This study investigated the effect of clubroot, a soilborne disease caused by Plasmodiophora brassicae, on plant hormones in Brassica napus. The results showed that the pathogen modulated plant hormonal networks, leading to increased levels of SA and ABA in susceptible plants, and decreased levels of JA. This modulation of plant hormones could be important for understanding plant defense mechanisms against clubroot.
Article
Plant Sciences
Yixiao Wang, Stephen E. E. Strelkov, Sheau-Fang Hwang
Summary: Blackleg, caused by Leptosphaeria maculans, is a significant disease of canola. Recently, Verticillium stripe has emerged as another disease threat. The study explored the impact of blackleg on yield using field experiments and evaluating different hybrids in commercial crops. It was found that the interaction between L. maculans/V. longisporum may cause more severe losses in canola, indicating the need for proactive disease management strategies.
Article
Horticulture
Brittany C. Hennig, Sheau-Fang Hwang, Victor P. Manolii, George Turnbull, Samuel V. J. Robinson, Stephen E. Strelkov
Summary: Plasmodiophora brassicae is a soilborne parasite causing clubroot disease in canola. The study found that the application of hydrated lime can decrease clubroot severity, increase crop yield, and reduce the density of P. brassicae.
