scholarly journals Effect of Temperature on Cortical Infection by Plasmodiophora brassicae and Clubroot Severity

2011 ◽  
Vol 101 (12) ◽  
pp. 1424-1432 ◽  
Author(s):  
Kalpana Sharma ◽  
Bruce D. Gossen ◽  
Mary Ruth McDonald
Keyword(s):  
Life Cycle ◽  
Brassica Rapa ◽  
Plasmodiophora Brassicae ◽  
Consistent Pattern ◽  
Effect Of Temperature ◽  
Symptom Development ◽  
Root Cortex ◽  
Brassica Crops ◽  
Resting Spores ◽  
Cortical Infection

A study was conducted to assess the effect of temperature on infection and development of Plasmodiophora brassicae in the root cortex of Shanghai pak choy (Brassica rapa subsp. chinensis) and on subsequent clubroot severity. Ten-day-old seedlings were grown individually, inoculated with resting spores, and maintained in growth cabinets at 10, 15, 20, 25, and 30°C. Seedlings were harvested at 2-day intervals, starting 8 days after inoculation (DAI) and continuing until 42 DAI. Roots were assessed at 4-day intervals for the incidence of cortical infection and stage of infection (young plasmodia, mature plasmodia, and resting spores), at 2-day intervals for symptom development and clubroot severity, and at 8-day intervals for the number of spores per gram of gall. Temperature affected every stage of clubroot development. Cortical infection was highest and symptoms were observed earliest at 25°C, intermediate at 20 and 30°C, and lowest and latest at 15°C. No cortical infection or symptoms were observed at 42 DAI in plants grown at 10°C. A substantial delay in the development of the pathogen was observed at 15°C. Resting spores were first observed at 38 DAI in plants at 15°C, 26 DAI at 20 and 30°C, and 22 DAI at 25°C. The yield of resting spores from galls was higher in galls that developed at 20 to 30°C than those that developed at 15°C over 42 days of assessment. These results support the observation in companion studies that cool temperatures result in slower development of clubroot symptoms in brassica crops, and demonstrate that the temperature has a consistent pattern of effect throughout the life cycle of the pathogen.

scholarly journals The Role of Primary and Secondary Infection in Host Response to Plasmodiophora brassicae

2014 ◽  
Vol 104 (10) ◽  
pp. 1078-1087 ◽  
Author(s):  
Mary Ruth McDonald ◽  
Kalpana Sharma ◽  
Bruce D. Gossen ◽  
Abhinandan Deora ◽  
Jie Feng ◽  
...  
Keyword(s):  
Plasmodiophora Brassicae ◽  
Secondary Infection ◽  
Root Hairs ◽  
Secondary Phase ◽  
Primary Phase ◽  
Root Cortex ◽  
Resting Spores ◽  
Cortical Infection ◽  
Root Hair Infection

The disease cycle of Plasmodiophora brassicae consists of a primary phase in root hairs followed by a secondary phase in the root cortex and adjacent tissues. However, the role of root hair infection in subsequent cortical infection and development of P. brassicae is not well understood. To examine the role of the primary and secondary stages separately, inoculation studies with resting spores (source of primary zoospores) and secondary zoospores of a virulent and avirulent pathotype were conducted on canola (Brassica napus). The size of secondary zoospores and number of nuclei were also examined. The zoospores were larger (≈9.6 to 14.4 μm) than in previous reports and all were uninucleate. Inoculation with secondary zoospores alone produced both primary and secondary infection, even with the avirulent pathotype. No symptoms developed from inoculation with avirulent primary zoospores but tiny, bead-shaped clubs developed from inoculation with avirulent secondary zoospores. Inoculation with virulent secondary zoospores alone resulted in lower disease severity than inoculation with virulent resting spores alone. The results indicate that recognition of infection by the host and initiation of a response (induction or suppression of resistance) occurs during primary infection, although recognition can also occur during cortical infection and development.

scholarly journals Brassica crops and a Streptomyces sp as potential biocontrol for clubroot of brassicas

2001 ◽  
Vol 54 ◽  
pp. 80-83 ◽  
Author(s):  
L-H Cheah ◽  
G. Kent ◽  
S. Gowers
Keyword(s):  
Brassica Rapa ◽  
Chinese Cabbage ◽  
Field Trial ◽  
Plasmodiophora Brassicae ◽  
Soil Samples ◽  
Streptomyces Sp ◽  
Brassica Crops ◽  
Glasshouse Experiment

Two glasshouse experiments and a field trial were carried out to evaluate the potential of brassica crops which contain high levels of glucosinolates for control of clubroot of brassicas Brassica rapa crops were grown for about 70 days in a field which was infested with Plasmodiophora brassicae In the first glasshouse experiment the leaf and stem of the plants were harvested chopped into small pieces and mixed with clubrootinfested soil in punnets Chinese cabbage seedlings were then transplanted into the punnets In the second glasshouse experiment soil samples were taken in punnets from plots where the B rapa crops had been rotary hoed and left to decompose for about three weeks Chinese cabbage seedlings were transplanted into the punnets In both experiments B rapatreated soil reduced (P

scholarly journals Wybrane zagadnienia z biologii grzyba Plasmodiophora brassicae Wor. [Some problems in the life-cycle of fungus Plasmodiophora brassicae, Wor.]

2015 ◽  
Vol 26 (1) ◽  
pp. 147-160 ◽  
Author(s):  
B. Nowicki
Keyword(s):  
Life Cycle ◽  
Soil Ph ◽  
Plasmodiophora Brassicae ◽  
Acid Soil ◽  
Infested Soil ◽  
Alkaline Soils ◽  
Resting Spores ◽  
Ph Range

The quickest loss of infectivity of <i>Plasmodiophora brassicae</i> Wor. resting spores was observed in acid soil. Jnlectivity was ratained longer in neutral and alkaline soils. The infection of cabbage seedlings took place in a broad pH range from 3.3 to 8.1, the optimum soil pH for infection being at 5.3 - 5.7. When the number of spores in the soil increased the infection took place in the infection took place in the broader pH range. The plants which were planted as seedlings in infested soil were infected in a broader pH range than plants which were grown from seeds in infested soil.

Germination of Plasmodiophora brassicae resting spores stimulated by a non-host plant

2005 ◽  
Vol 113 (3) ◽  
pp. 275-281 ◽  
Author(s):  
Hanna Friberg ◽  
Jan Lagerlöf ◽  
Birgitta Rämert
Keyword(s):  
Host Plant ◽  
Plasmodiophora Brassicae ◽  
Resting Spores

The life history of Plasmodiophora brassicae Woron

1972 ◽  
Vol 180 (1058) ◽  
pp. 103-112 ◽  
Keyword(s):  
Life History ◽  
Root Hair ◽  
Plasmodiophora Brassicae ◽  
Root Hairs ◽  
Secondary Phase ◽  
Tissue Cultures ◽  
Resting Spore ◽  
Resting Spores ◽  
Seedling Roots ◽  
History Of

Resting spore germination and the root hair stages of the life history of Plasmodiophora brassicae were studied in stained preparations of infected Brassica rapa seedling roots. Naked protoplasts, usually possessing two unequal flagella, were released from resting spores through a small circular pore. They penetrated the root hairs of B. rapa and there developed into plasmodia which, after becoming multinucleate, cleaved to form zoosporangia con­taining incipient zoospores. Biflagellate zoospores were released from root hair zoosporangia and fused in pairs, although karyogamy did not occur. The resulting binucleate zoospores infected the cortical dells of B. rapa to form binucleate plasmodia, the earliest stages of the secondary phase of the life history. These findings are discussed in relation to previous studies on the life history of P. brassicae in Brassica plants and in Brassica tissue cultures, and a new complete life history, including nuclear fusion in the secondary plasmodium, is suggested for the organism.

Life Cycle of Plasmodiophora brassicae

2009 ◽  
Vol 28 (3) ◽  
pp. 203-211 ◽  
Author(s):  
Koji Kageyama ◽  
Takahiro Asano
Keyword(s):  
Life Cycle ◽  
Plasmodiophora Brassicae

scholarly journals Mining of Brassica-Specific Genes (BSGs) and Their Induction in Different Developmental Stages and under Plasmodiophora brassicae Stress in Brassica rapa

2018 ◽  
Vol 19 (7) ◽  
pp. 2064 ◽  
Author(s):  
Mingliang Jiang ◽  
Xiangshu Dong ◽  
Hong Lang ◽  
Wenxing Pang ◽  
Zongxiang Zhan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Brassica Rapa ◽  
Developmental Stages ◽  
Plasmodiophora Brassicae ◽  
Expression Patterns ◽  
Gc Content ◽  
Biological Information ◽  
Lower Percentage ◽  
Orphan Genes ◽  
Conserved Genes

Orphan genes, also called lineage-specific genes (LSGs), are important for responses to biotic and abiotic stresses, and are associated with lineage-specific structures and biological functions. To date, there have been no studies investigating gene number, gene features, or gene expression patterns of orphan genes in Brassica rapa. In this study, 1540 Brassica-specific genes (BSGs) and 1824 Cruciferae-specific genes (CSGs) were identified based on the genome of Brassica rapa. The genic features analysis indicated that BSGs and CSGs possessed a lower percentage of multi-exon genes, higher GC content, and shorter gene length than evolutionary-conserved genes (ECGs). In addition, five types of BSGs were obtained and 145 out of 529 real A subgenome-specific BSGs were verified by PCR in 51 species. In silico and semi-qPCR, gene expression analysis of BSGs suggested that BSGs are expressed in various tissue and can be induced by Plasmodiophora brassicae. Moreover, an A/C subgenome-specific BSG, BSGs1, was specifically expressed during the heading stage, indicating that the gene might be associated with leafy head formation. Our results provide valuable biological information for studying the molecular function of BSGs for Brassica-specific phenotypes and biotic stress in B. rapa.

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

Plant Disease ◽  
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.

Refining the Life Cycle of Plasmodiophora brassicae

2020 ◽  
Vol 110 (10) ◽  
pp. 1704-1712 ◽  
Author(s):  
Lijiang Liu ◽  
Li Qin ◽  
Zhuqing Zhou ◽  
Wilhelmina G. H. M. Hendriks ◽  
Shengyi Liu ◽  
...  
Keyword(s):  
Life Cycle ◽  
Plasmodiophora Brassicae ◽  
Secondary Infection ◽  
Life Stage ◽  
Infection Process ◽  
Epidermal Cells ◽  
Sexual Life ◽  
Cortical Cells ◽  
Susceptible Host ◽  
Clubroot Disease

As a soilborne protist pathogen, Plasmodiophora brassicae causes the devastating clubroot disease on Brassicaceae crops worldwide. Due to its intracellular obligate biotrophic nature, the life cycle of P. brassicae is still not fully understood. Here, we used fluorescent probe-based confocal microscopy and transmission electron microscopy (TEM) to investigate the infection process of P. brassicae on the susceptible host Arabidopsis under controlled conditions. We found that P. brassicae can initiate the primary infection in both root hairs and epidermal cells, producing the uninucleate primary plasmodium at 1 day postinoculation (dpi). After that, the developed multinucleate primary plasmodium underwent condensing and cytoplasm cleavage into uninucleate zoosporangia from 1 to 4 dpi. This was subsequently followed by the formation of multinucleate zoosporangia and the production of secondary zoospores within zoosporangium. Importantly, the secondary zoospores performed a conjugation in the root epidermal cells after their release. TEM revealed extensive uninucleate secondary plasmodium in cortical cells at 8 dpi, indicating the establishment of the secondary infection. The P. brassicae subsequently developed into binucleate, quadrinucleate, and multinucleate secondary plasmodia from 10 to 15 dpi, during which the clubroot symptoms appeared. The uninucleate resting spores were first observed in the cortical cells at 24 dpi, marking the completion of a life cycle. We also provided evidence that the secondary infection of P. brassicae may represent the diploid sexual life stage. From these findings, we propose a refined life cycle of P. brassicae which will contribute to understanding of the complicated infection biology of P. brassicae.

Sign in / Sign up

Export Citation Format

Share Document