scholarly journals Investigation of Streptomyces scabies Causing Potato Scab by Various Detection Techniques, Its Pathogenicity and Determination of Host-Disease Resistance in Potato Germplasm

Pathogens ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 760
Author(s):  
Sohaib Ismail ◽  
Bo Jiang ◽  
Zohreh Nasimi ◽  
M. Inam-ul-Haq ◽  
Naoki Yamamoto ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Common Scab ◽  
Streptomyces Scabies ◽  
Potato Cultivars ◽  
Potato Tubers ◽  
Streptomyces Species ◽  
Detection Techniques ◽  
Streptomyces Spp ◽  
Geographical Regions

Streptomyces scabies is a Gram-positive bacterial pathogen that causes common scab disease to several crops, particularly in the potato. It is a soil borne pathogen, a very devastating scab pathogen and difficult to manage in the field. Streptomyces has several species that cause common scab such as S. scabiei, S. acidiscabies, S. europaeiscabiei, S. luridiscabiei, S. niveiscabiei, S. puniciscabiei, S. reticuliscabiei, S. stelliscabiei, S. turgidiscabies, S. ipomoeae. Common scab disease harmfully affects potato economic and market value due to the presence of black spots on the tuber. Owing to its genetic diversity and pathogenicity, the determination of pathogen presence in potato fields is still challenging. In this study, S. scabies genetic diversity was measured by surveying five potato-growing areas of Pakistan during the growing season 2019. A total of 50 Streptomyces isolates, including S. scabies, S. acidiscabies, S. griseoflavus were isolated and identified based on morphologic, biochemical and molecular analysis. Virulent confirmation assays confirmed ten virulent strains of Streptomyces spp. On the potato cultivars Cardinal and Santee. Among the Streptomyces species, S. scabies showed the highest scab index, followed by S. acidiscabies and S. griseoflavus by exhibiting the scab-like lesions on potato tubers. Ten potato cultivars were screened against these virulent isolates of Streptomyces. The Faisalabad white variety showed the highest scab index followed By Cardinal, Tourag, Kuroda, Santee, Lady Rosetta, Asterix, Diamant, Faisalabad red and Sadaf. Moreover, genetic diversity and pathogenicity of Streptomyces spp. on potato tubers were also likely diverse in different geographical regions and also potato cultivars. This study represents a contribution to understanding the local interaction between potatoes and Streptomyces spp. in Pakistan. It will aid in supporting a solution for the management of this pathogen around the world.

scholarly journals Isolation and Characterization of Plant-Pathogenic Streptomyces Species Associated with Common Scab-Infected Potato Tubers in Newfoundland

2016 ◽  
Vol 106 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Joanna K. Fyans ◽  
Luke Bown ◽  
Dawn R. D. Bignell
Keyword(s):  
Common Scab ◽  
Virulence Gene ◽  
Potato Scab ◽  
Potato Tubers ◽  
Streptomyces Species ◽  
Genus Streptomyces ◽  
Thaxtomin A ◽  
Streptomyces Spp ◽  
Putative Virulence Gene ◽  
Isolation And Characterization

Potato common scab (CS) is an economically important crop disease that is caused by several members of the genus Streptomyces. In this study, we characterized the plant-pathogenic Streptomyces spp. associated with CS-infected potato tubers harvested in Newfoundland, Canada. A total of 17 pathogenic Streptomyces isolates were recovered from potato scab lesions, of which eight were determined to be most similar to the known CS pathogen S. europaeiscabiei. All eight S. europaeiscabiei isolates were found to produce the thaxtomin A phytotoxin and to harbor the nec1 virulence gene, and most also carry the putative virulence gene tomA. The remaining isolates appear to be novel pathogenic species that do not produce thaxtomin A, and only two of these isolates were determined to harbor the nec1 or tomA genes. Of the non-thaxtomin-producing isolates, strain 11-1-2 was shown to exhibit a severe pathogenic phenotype against different plant hosts and to produce a novel, secreted phytotoxic substance. This is the first report documenting the plant-pathogenic Streptomyces spp. associated with CS disease in Newfoundland. Furthermore, our findings provide further evidence that phytotoxins other than thaxtomin A may also contribute to the development of CS by Streptomyces spp.

scholarly journals Characterization of a New Streptomyces Strain, DS3024, That Causes Potato Common Scab

Plant Disease ◽  
2009 ◽  
Vol 93 (12) ◽  
pp. 1329-1334 ◽  
Author(s):  
J. J. Hao ◽  
Q. X. Meng ◽  
J. F. Yin ◽  
W. W. Kirk
Keyword(s):  
Common Scab ◽  
Potato Tubers ◽  
North Central ◽  
Thaxtomin A ◽  
The North ◽  
Streptomyces Spp ◽  
Common Marker ◽  
Central United States ◽  
Potato Common Scab

A novel strain of Streptomyces (named DS3024) was isolated from a potato field in Michigan in 2006. The taxonomy of the organism was determined by morphology, biochemistry, and genetic analysis. Analysis of the 16S ribosomal RNA gene sequence indicated that the organism was most similar to an isolate of Streptomyces sp., ME02-6979.3a, which is not pathogenic to potato tubers but is distinct from other known pathogenic Streptomyces spp. Strain DS3024 has genes that encode thaxtomin synthetase (txtAB), which is required for pathogenicity and virulence, and tomatinase (tomA), which is a common marker for many pathogenic Streptomyces spp. However, the nec1 gene (associated with virulence in most pathogenic Streptomyces spp.) was not detected. The new strain was capable of growth at pH 4.5, caused necrosis on potato tuber slices, and produced thaxtomin A. In greenhouse experiments, DS3024 caused scab symptoms on potato tubers similar to those caused by Streptomyces scabies on tubers of potato cv. Atlantic, which is scab susceptible. We propose that DS3024 is a new strain of Streptomyces capable of causing common scab on potato tubers. The prevalence of this strain of Streptomyces in potato-producing areas in the north-central United States has not been determined.

scholarly journals Using the TxtAB Operon to Quantify Pathogenic Streptomyces in Potato Tubers and Soil

2008 ◽  
Vol 98 (4) ◽  
pp. 405-412 ◽  
Author(s):  
Xinshun Qu ◽  
Leslie A. Wanner ◽  
Barbara J. Christ
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Pathogenic Bacteria ◽  
Common Scab ◽  
Cost Effective ◽  
Potato Tubers ◽  
Pcr Assay ◽  
Streptomyces Species ◽  
Standard Curve ◽  
Target Dna

The phytotoxin thaxtomin, produced by plant pathogenic Streptomyces species, is the only known pathogenicity determinant for common scab diseases of potato and other root and tuber crops. Genes encoding thaxtomin synthetase (txtAB) are found on a pathogenicity island characteristic of genetically diverse plant pathogenic Streptomyces species. In this study, an SYBR Green quantitative real-time polymerase chain reaction (PCR) assay using primers designed to anneal to the txtAB operon of Streptomyces was developed to quantify pathogenic bacterial populations in potatoes and soil. The real-time PCR assay was specific for pathogenic Streptomyces strains. The detection limit of the assay was 10 fg of the target DNA, or one genome equivalent. Cycle threshold (Ct) values were linearly correlated with the concentration of the target DNA (correlation coefficient R2 = 0.99) and were not affected by the presence of plant DNA extracts, indicating the usefulness of the assay for quantitative analyses of the pathogenic bacteria in plant tissues. The amount of pathogenic Streptomyces DNA in total DNA extracts from 1 g asymptomatic and symptomatic tubers was quantified using the assay and ranged from 101 to 106 pg. A standard curve was established to quantify pathogenic Streptomyces in soil. Using the standard curve, numbers of pathogenic Streptomyces colony forming units were extrapolated to range from 103 to 106 per gram of soil from potato fields where common scab was found. This real-time PCR assay using primers designed from the txtAB operon allows rapid, accurate, and cost effective quantification of pathogenic Streptomyces strains in potato tubers and in soil.

Management of common scab of potato using planting and harvest dates

2002 ◽  
Vol 82 (1) ◽  
pp. 185-189 ◽  
Author(s):  
D. Waterer
Keyword(s):  
Solanum Tuberosum ◽  
Disease Management ◽  
Common Scab ◽  
Potato Scab ◽  
Streptomyces Species ◽  
Early Planting ◽  
Streptomyces Spp ◽  
Harvest Dates ◽  
Tuber Grade ◽  
Cropping Seasons

The influences of planting and harvest dates on yields and grade-out due to tuber damage by common scab (Streptomyces spp.) were evaluated over three cropping seasons using two cultivars of potato (Solanum tuberosum) grown on land heavily infested with pathogenic Streptomyces species. Early planting and delaying the harvest enhanced yields in both cultivars, but also increased tuber grade-out due to excessive levels of scab. Delaying the harvest reduced marketable yields more than did early planting. The longer harvest was delayed after top-kill, the greater was the grade out due to scab. Increased losses to scab exceeded any increase in tuber yields obtained by delaying harvest. This study demonstrates that common scab of potato may be managed by minimizing the period the crop is in the ground, but that this method of disease management is achieved at the expense of yields. Early planting coupled with timely harvesting after kill-down of the tops appears to be an effective compromise between the objectives of maximizing yields while avoiding excessive grade-out due to common scab. Key words: Potato scab, Streptomyces scabies, Solanum tuberosum, agronomy

Responses of potato cultivars to the common scab pathogens, Streptomyces scabies and S. turgidiscabies

2005 ◽  
Vol 146 (3) ◽  
pp. 395-403 ◽  
Author(s):  
L H HILTUNEN ◽  
A WECKMAN ◽  
A YLHAINEN ◽  
H RITA ◽  
E RICHTER ◽  
...  
Keyword(s):  
Common Scab ◽  
Streptomyces Scabies ◽  
Potato Cultivars ◽  
The Common

scholarly journals DETERMINATION OF GENETIC DIVERSITY IN PORTUNUS PELAGICUS (LINNAEUS, 1758) COLLECTED FROM GULF OF MANNAR

2021 ◽  
Vol 9 (03) ◽  
pp. 409-420
Author(s):  
C. Shibana ◽  
◽  
P. Subavathy ◽  
Keyword(s):  
Genetic Diversity ◽  
Rapd Analysis ◽  
Gulf Of Mannar ◽  
High Genetic Diversity ◽  
Portunus Pelagicus ◽  
Specific Level ◽  
Main Emphasis ◽  
Geographical Regions ◽  
High Level

In the present study, the marine crab Portunuspelagicus was screened with 17 primers and made to score polymorphism. The main emphasis of the present study was to assess the genetic diversity at intra specific level among the 3 accessions of P. pelagicus species of Gulf of Mannarusing RAPD markers. RAPD analysis shows that there is a high level of polymorphism among different accessions. From this study, it was understood that each location varied with respect to environmental factors and genetic parameters. The OPB-18, OPB-19, OPC-07 and OPN-06 primers produced distinct, highly reproducible amplification profile for all the screened samples. In the present study, amplification bands ranged between 250 and 663 bp. Maximum numbers of bands were produced by OPN-06 and least by OPB-19. Moderate to high genetic diversity was observed in all geographic samples of P. pelagicus from RAPD analysis. RAPD analysis from three different geographical regions shows clear polymorphic patterns. Thoothukudi and Rameshwaram populations appear in one cluster, while the Kanyakumari populations formed the other cluster indicating a genetic variability and diversity in samples collected from different places.

Sign in / Sign up

Export Citation Format

Share Document