ClubrootTracker: A Resource to Plan a Clubroot-Free Farm

Clubroot is a devastating disease affecting cruciferous crops worldwide. Clubroot was first described in the 13th century in Russia and from that moment has been affecting European, Asian, and American brassica production. Plasmodiophora brassicae is the clubroot causal agent, and it is an obligate intracellular parasite that, as soil-borne resting spores, can remain viable in soil for many years. This persistence in the soil is a major negative contributing factor to the management of clubroot disease and highlights the importance for brassica growers to have ready access to current information on the distribution of the pathogen. The interactive online tool ClubrootTracker ( http://clubroottracker.ca ) has been developed to enable users to view pathogen and disease presence in geographic locations across the world. ClubrootTracker, as described in this manuscript, has been developed to provide brassica farmers a tool that will contribute to clubroot management and aid in planning a clubroot-free farm. This tool is an open resource that has the main goal of acquisition of GPS information in reporting the pathogen or the disease by the researchers working with it around the world.

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Faculty Opinions recommendation of The genome of the obligate intracellular parasite Trachipleistophora hominis: new insights into microsporidian genome dynamics and reductive evolution.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717961260.793464033 ◽

2012 ◽

Author(s):

William Martin

Keyword(s):

Intracellular Parasite ◽

Reductive Evolution ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite ◽

Genome Dynamics

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Influence of host reproductive state onSphaerothecum destruensprevalence and infection level

Parasitology ◽

10.1017/s0031182010000983 ◽

2010 ◽

Vol 138 (1) ◽

pp. 26-34 ◽

Cited By ~ 14

Author(s):

D. ANDREOU ◽

M. HUSSEY ◽

S. W. GRIFFITHS ◽

R. E. GOZLAN

Keyword(s):

Detection Limit ◽

Real Time ◽

Genomic Dna ◽

Adverse Impact ◽

Intracellular Parasite ◽

Reproductive State ◽

Chain Reaction ◽

Infection Level ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite

SUMMARYSphaerothecum destruensis an obligate intracellular parasite with the potential to cause high mortalities and spawning inhibition in the endangered cyprinidLeucaspius delineatus. We investigated the influence ofL. delineatus’s reproductive state on the prevalence and infection level ofS. destruens. A novel real time quantitative polymerarse chain reaction (qPCR) was developed to determineS. destruens’ prevalence and infection level. These parameters were quantified and compared in reproductive and non-reproductiveL. delineatus. The detection limit of theS. destruensspecific qPCR was determined to be 1 pg of purifiedS. destruensgenomic DNA. Following cohabitation in the lab, reproductiveL. delineatushad a significantly higherS. destruensprevalence (P<0·05) and infection levels (P<0·01) compared to non-reproductiveL. delineatus. S. destruensprevalence was 19% (n=40) in non-reproductiveL. delineatusand 41% (n=32) in reproductiveL. delineatus. However, there was no difference inS. destruensprevalence in reproductive and non-reproductive fish under field conditions. Mean infection levels were 18 and 99 pgS. destruensDNA per 250 ngL. delineatusDNA for non-reproductive and reproductiveL. delineatusrespectively. The present work indicates thatS. destruensinfection inL. delineatuscan be influenced by the latter's reproductive state and provides further support for the potential adverse impact ofS. destruenson the conservation ofL. delineatuspopulations.

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Effect of pathogen virulence on pathogenicity, host range and reproduction of Plasmodiophora brassicae, the causal agent of clubroot disease

Plant Disease ◽

10.1094/pdis-02-21-0410-re ◽

2021 ◽

Author(s):

Nazanin Zamani-Noor ◽

Sinja Brand ◽

Hans-Peter Soechting

Keyword(s):

Plasmodiophora Brassicae ◽

Brassica Species ◽

Post Inoculation ◽

Clubroot Disease ◽

Alopecurus Myosuroides ◽

Pathogen Virulence ◽

Iberis Amara ◽

Thlaspi Arvense ◽

Resting Spores ◽

Pathogen Dna

A series of greenhouse experiments was conducted to evaluate the effect of Plasmodiophora brassicae virulence on clubroot development and propagation of resting spores in 86 plant species from 19 botanical families. Plants were artificially inoculated with two isolates of P. brassicae, which were either virulent on clubroot-resistant oilseed rape cv. Mendel (P1 (+)) or avirulent on this cultivar (P1). Clubroot severity and the number of resting spores inside the roots were assessed 35 days post inoculation. Typical clubroot symptoms were observed only in the Brassicaceae family. P1 (+)-inoculated species exhibited more severe symptoms (2 to 10–fold more severe), bigger galls (1.1 to 5.8 fold heavier) and higher number of resting spores than the P1-inoculated plants. Among all Brassica species, Bunias orientalis, Coronopus squamatus and Raphanus sativus were fully resistant against both isolates, while Camelina sativa, Capsella bursa-pastoris, Coincya momensis, Descurainia sophia, Diplotaxis muralis, Erucastrum gallicum, Neslia paniculata, Sinapis alba, S. arvensis, Sisymbrium altissimum, S. loeselii and Thlaspi arvense were highly susceptible. Conringia orientalis, Diplotaxis tenuifolia, Hirschfeldia incana, Iberis amara, Lepidium campestre and Neslia paniculata were completely or partially resistant to P1-isolate but highly susceptible to P1 (+). These results propose that the basis for resistance in these species may be similar to that found in some commercial cultivars, and that these species could contribute to the build-up of inoculum of virulent pathotypes. Furthermore, the pathogen DNA was detected in Alopecurus myosuroides, Phacelia tanacatifolia, Papaver rhoeas and Pisum sativum. It can concluded that the number and diversity of hosts for P. brassicae are greater than previously reported.

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Enteric infection with an obligate intracellular parasite, Encephalitozoon cuniculi, in an experimental model.

Infection and Immunity ◽

10.1128/iai.59.7.2225-2231.1991 ◽

1991 ◽

Vol 59 (7) ◽

pp. 2225-2231 ◽

Cited By ~ 19

Author(s):

V Wicher ◽

R E Baughn ◽

C Fuentealba ◽

J A Shadduck ◽

F Abbruscato ◽

...

Keyword(s):

Experimental Model ◽

Enteric Infection ◽

Intracellular Parasite ◽

Encephalitozoon Cuniculi ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite

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A selector of transcription initiation in the protozoan parasite Toxoplasma gondii.

Molecular and Cellular Biology ◽

10.1128/mcb.15.1.87 ◽

1995 ◽

Vol 15 (1) ◽

pp. 87-93 ◽

Cited By ~ 88

Author(s):

D Soldati ◽

J C Boothroyd

Keyword(s):

Toxoplasma Gondii ◽

Gene Transcription ◽

Transcription Initiation ◽

Protozoan Parasite ◽

Intracellular Parasite ◽

Transcription Start ◽

Transcription Start Sites ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite ◽

Sag1 Gene

The recent development of an efficient transfection system for the apicomplexan Toxoplasma gondii allows a comprehensive dissection of the elements involved in gene transcription in this obligate intracellular parasite. We demonstrate here that for the SAG1 gene, a stretch of six repeated sequences in the region 35 to 190 bp upstream of the first of two transcription start sites is essential for efficient and accurate transcription initiation. This repeat element shows characteristics of a selector in determining the position of the transcription start sites.

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Infected Dendritic Cells Facilitate Systemic Dissemination and Transplacental Passage of the Obligate Intracellular Parasite Neospora caninum in Mice

PLoS ONE ◽

10.1371/journal.pone.0032123 ◽

2012 ◽

Vol 7 (3) ◽

pp. e32123 ◽

Cited By ~ 44

Author(s):

Esther Collantes-Fernandez ◽

Romanico B. G. Arrighi ◽

Gema Álvarez-García ◽

Jessica M. Weidner ◽

Javier Regidor-Cerrillo ◽

...

Keyword(s):

Dendritic Cells ◽

Neospora Caninum ◽

Intracellular Parasite ◽

Transplacental Passage ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite ◽

Systemic Dissemination

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Chlamydia isopodii sp. n., an Obligate Intracellular Parasite of Porcellio scaber

Pathobiology ◽

10.1159/000163303 ◽

1985 ◽

Vol 53 (2) ◽

pp. 115-120 ◽

Cited By ~ 1

Author(s):

Michael T. Shay ◽

Annemarie Bettica ◽

G.M. Vernon ◽

E.R. Witkus

Keyword(s):

Intracellular Parasite ◽

Porcellio Scaber ◽

Obligate Intracellular ◽

Obligate Intracellular Parasite

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First Report of Clubroot on Capsella bursa-pastoris Caused by Plasmodiophora brassicae in Sichuan Province of China

Plant Disease ◽

10.1094/pdis-04-13-0395-pdn ◽

2014 ◽

Vol 98 (5) ◽

pp. 687-687 ◽

Cited By ~ 2

Author(s):

L. Ren ◽

X. P. Fang ◽

C. C. Sun ◽

K. R. Chen ◽

F. Liu ◽

...

Keyword(s):

Plasmodiophora Brassicae ◽

Tap Water ◽

Disease Incidence ◽

Morphological Characteristics ◽

Pcr Amplification ◽

Sichuan Province ◽

Clubroot Disease ◽

Cruciferous Vegetable ◽

First Report ◽

Resting Spores

Shepherd's purse (Capsella bursa-pastoris (L.) Medicus) is an edible and wild medicinal plant widely distributed in China. This plant has been cultivated in Shanghai, China, since the end of the 19th century. Infection of C. bursa-pastoris by Plasmodiophora brassicae, the causal agent of clubroot disease on Brassica spp. has been reported in Korea (2), but is not known to occur in China. In February of 2011, stunted and wilted shepherd's purse (SP) plants were observed in a field planted to oilseed rapes (B. napus) in Sichuan Province of China. Symptomatic SP plants also exhibited root galls. Disease incidence was 6.2% and 100% for SP and B. napus, respectively. Root galls on diseased SP plants were collected for pathogen identification. Many resting spores were observed when the root galls were examined under a light microscope. The resting spores were circular in shape, measuring 2.0 to 3.1 μm in diameter (average 2.6 μm). PCR amplification was conducted to confirm the pathogen. DNA was extracted from root galls and healthy roots (control) of SP. Two primers, TC2F (5′-AAACAACGAGTCAGCTTGAATGCTAGTGTG-3′) and TC2R (5′-CTTTAGTTGTGTTTCGGCTAGGATGGTTCG-3′) were used to detect P. brassicae (1). No PCR amplifications were observed with the control DNA as template. A fragment of the expected size (approximately 520 bp) was obtained when DNA was amplified from diseased roots of SP. These results suggest that the pathogen in the galled roots of SP is P. brassicae. Pathogenicity of P. brassicae in SP was tested on plants of both SP and Chinese cabbage (CC) (B. campestris ssp. pekinensis). A resting spore suspension prepared from naturally infected SP roots was mixed with a sterilized soil in two plastic pots, resulting in a final concentration of 5 × 106 spores/g soil. Soil treated with the same volume of sterile water was used as a control. Seeds of SP and CC were pre-germinated on moist filter paper for 2 days (20°C) and seeded into the infested and control pots, one seed per pot for planted for CC and four seeds per pot for SP. The pots were placed in a chamber at 15 to 25°C under 12 h light and 12 h dark. Plants in each pot were uprooted after 4 weeks and the roots of each plant were washed under tap water and rated for clubroot disease. No disease symptoms were observed in the control treatments of SP or CC. Plants of both species showed symptoms of clubroot, with the disease incidence of 62.5% and 100% on SP and CC, respectively. The pathogen was isolated from diseased roots of each plant and confirmed as P. brassicae based on morphological characteristics and PCR detection. To our knowledge, this is the first report of clubroot disease on C. bursa-pastoris in Sichuan Province of China. This finding suggests that it may be necessary to manage C. bursa-pastoris in cruciferous vegetable (cabbage, turnip) and oilseed rape production fields. References: (1) T. Cao et al. Plant Dis. 91:80, 2007. (2) W. G. Kim et al. Microbiology 39:233, 2011.

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