scholarly journals Morphological, Pathogenic, and Molecular Characterization of Alternaria Isolates Associated with Alternaria Late Blight of Pistachio

2002 ◽  
Vol 92 (4) ◽  
pp. 406-416 ◽  
Author(s):  
Barry M. Pryor ◽  
Themis J. Michailides
Keyword(s):  
Sequence Data ◽  
Morphological Characteristics ◽  
Intergenic Spacer ◽  
Rflp Analysis ◽  
Species Group ◽  
Molecular Characteristics ◽  
Pcr Rflp ◽  
Species Groups ◽  
Selection Of

Alternaria isolates were obtained from various pistachio tissues collected in five orchards in California. For all isolates, morphological characteristics of the colony and sporulation apparatus were determined and compared with those of representative isolates of A. alternata, A. tenuissima, A. arborescens, and A. infectoria. A selection of the pistachio isolates and the representative Alternaria isolates were evaluated for pathogenicity to pistachio. Molecular characteristics of these isolates were determined using random amplified polymorphism DNA (RAPD) analysis, polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis of nuclear intergenic spacer rDNA, and sequence analysis of nuclear internal transcribed spacer (ITS) rDNA. Based on morphological characteristics, the pistachio isolates were grouped as identical or very similar to either A. alternata, A. tenuissima, A. arborescens, or A. infectoria. Isolates from the alternata, tenuissima, and arborescens species-groups were pathogenic to pistachio and no significant differences in pathogenicity were observed. Isolates from the infectoria species-group were only weakly pathogenic to pistachio. Based on cluster analysis of RAPD and PCR-RFLP data, three distinct clusters were evident; the infectoria cluster, the arborescens cluster, and a combined alternata/tenuissima cluster. Based on analysis of ITS sequence data, the infectoria species-group was phylogenetically distinct from the other species-groups. Isolates of the alternata, tenuissima, and arborescens species-groups comprised a monophyletic clade in which the three species-groups could not be further resolved.

Characterization of Fusarium spp. isolates by PCR-RFLP analysis of the intergenic spacer region of the rRNA gene (rDNA)

2006 ◽  
Vol 106 (3) ◽  
pp. 297-306 ◽  
Author(s):  
A. Llorens ◽  
M.J. Hinojo ◽  
R. Mateo ◽  
M.T. González-Jaén ◽  
F.M. Valle-Algarra ◽  
...  
Keyword(s):  
Intergenic Spacer ◽  
Rflp Analysis ◽  
Rrna Gene ◽  
Fusarium Spp ◽  
Intergenic Spacer Region ◽  
Pcr Rflp

Characterization of natural populations of Nitrobacter spp. using PCR/RFLP analysis of the ribosomal intergenic spacer

1992 ◽  
Vol 157 (2) ◽  
pp. 107-115 ◽  
Author(s):  
Elisabeth Navarro ◽  
Pascal Simonet ◽  
Philippe Normand ◽  
René Bardin
Keyword(s):  
Natural Populations ◽  
Intergenic Spacer ◽  
Rflp Analysis ◽  
Ribosomal Intergenic Spacer ◽  
Pcr Rflp

Revision of the Metallactus kollari species-group with a new diagnosis of the genus (Coleoptera: Chrysomelidae: Cryptocephalinae)

Zootaxa ◽  
2018 ◽  
Vol 4413 (1) ◽  
pp. 57
Author(s):  
DAVIDE SASSI
Keyword(s):  
Type Species ◽  
Species Group ◽  
Identification Key ◽  
Original Diagnosis ◽  
Taxonomic Treatment ◽  
Species Groups ◽  
New Diagnosis ◽  
Good Resource

The genus Metallactus has been controversial since its introduction due to the ambiguous nature of the original diagnosis. This has caused some confusion in the taxonomy of Neotropical Pachybrachina. In this work the morphology of endophallus, which is useful for the characterization of species groups in several groups of Coleoptera, including Cryptocephalinae, has been analyzed. This has proven to be a good resource also in the taxonomic treatment of the species belonging to the genus Metallactus. After a careful survey on most of the species described so far, the endophallus shape in Metallactus turned out to be remarkably distinctive and very promising in the delimitation of species groups. The present work includes: a) a new diagnosis of the genus Metallactus on the basis of the aedeagal anatomy; b) the designation of the type species of the nominal genus; c) the revision of a first species-group of the genus, including the type species, hereinafter called Metallactus kollari species-group. Before this revision, catalogues had been reporting 13 species attributable to this group, in the present work three species have been synonymized and seven have been described as new to science. Therefore, the group includes 17 species. The species described as new are: Metallactus rileyi n. sp., M. bellatrix n. sp., M. longicornis n. sp.; M. londonpridei n. sp., M. regalini n. sp., M. bezoar n. sp., M. guarani n. sp. The new synonymies are as follows: Metallactus albipes Suffrian, 1866 (= M. nigrofasciatus Suffrian, 1866 n. syn.), M. albifrons Suffrian, 1866 (= M. flavofrontalis Jacoby, 1907 n. syn.), M. dodecastictus Suffrian, 1866 (= Griburius nigritarsis Jacoby, 1907 n. syn.). The lectotypes of all previously described species have been designated. The new synonymies, the name-bearing type fixations and designations and the nomenclatural acts have been critically discussed. An identification key for the species-group is also provided. 

scholarly journals Molecular Characterization of Pathogenicity Locus (PaLoc) and tcdC Genetic Diversity Among tcdA+B+ Clostridioides Difficile Clinical Isolates in Tehran, Iran

2020 ◽  
Author(s):  
Mansoor Kodori ◽  
Zohreh Ghalavand ◽  
Abbas Yadegar ◽  
Gita Eslami ◽  
Masoumeh Azimirad ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Molecular Characterization ◽  
Disease Severity ◽  
Genetic Variants ◽  
Rflp Analysis ◽  
Clostridioides Difficile ◽  
Pcr Rflp ◽  
The Common ◽  
Healthcare Associated

Abstract Background: Clostridioides difficile is the main cause of healthcare-associated diarrhea worldwide. It is proposed that certain C. difficile toxinotypes with distinct pathogenicity locus (PaLoc) variants are associated with disease severity and outcomes. Additionally, few studies have described the common C. difficile toxinotypes, and also little is known about the tcdC variants in Iranian isolates. We characterized the toxinotypes and the tcdC genotypes from a collection of Iranian clinical C. difficile tcdA+B+ isolates with known ribotypes (RTs).Methods: Fifty C. difficile isolates with known RTs and carrying the tcdA and tcdB toxin genes were analyzed. Toxinotyping was carried out based on a PCR-RFLP analysis of a 19.6 kb region encompassing the PaLoc. Genetic diversity of the tcdC gene was determined by the sequencing of the gene.Results: Of the 50 C. difficile isolates investigated, five distinct toxinotypes were recognized. Toxinotypes 0 (33/50, 66%) and V (11/50, 22%) were the most frequently found. C. difficile isolates of the toxinotype 0 mostly belonged to RT 001 (12/33, 36.4%), whereas toxinotype V consisted of RT 126 (9/11, 81.8%). The tcdC sequencing showed six variants (35/50, 70%); tcdC-sc3 (24%), tcdC-A (22%), tcdC-sc9 (18%), tcdC-B (2%), tcdC-sc14 (2%), and tcdC-sc15 (2%). The remaining isolates were wild-types (15/50, 30%) in the tcdC gene.Conclusions: The present study demonstrates that the majority of clinical tcdA+B+ isolates of C. difficile frequently harbor tcdC genetic variants. We also found that the RT 001/ toxinotype 0 and the RT 126/ toxinotype V are the most common types among Iranian isolates. Further studies are needed to investigate the putative association of various tcdC genotypes with CDI severity and its recurrence.

scholarly journals Phylogenetic Relationships of Local Durian Species based on Morphological Characteristics and PCR-RFLP Analysis of the Ribosomal Internal Transcribed Spacer (ITS) DNA

2016 ◽  
Vol 8 (3) ◽  
pp. 362
Author(s):  
Fidia Fibriana ◽  
Lutfia Nur Hadiyanti
Keyword(s):  
Phylogenetic Relationships ◽  
Internal Transcribed Spacer ◽  
Morphological Characteristics ◽  
Biology Education ◽  
Rflp Analysis ◽  
Restriction Pattern ◽  
Internal Transcribed Spacers ◽  
Central Java ◽  
Pcr Rflp ◽  
Pcr Products

<p>In this study, twenty local durian accessions obtained from Central Java in situ collection were characterized using the morphological characteristics and the restriction patterns which generated from the region spanning the internal transcribed spacers ITS LEU and ITS 4. Morphological characteristics of durian leaf, stem, tree, and fruit showed variations for the different accessions, whereas polymerase chain reaction (PCR) products of ribosomal DNA region showed a low length of variation. The size of the PCR products and the restriction analyses with the restriction endonucleases Bsp1431yielded a restriction pattern for each accessions. The results of this study can be utilized by local durian farmers as a preliminary reference for durian propagation. The data obtained need to be supported by further research using the other molecular markers to obtain more accurate data. The clear identity of durian species can help the management of propagation systems by farmers to get superior local durian.</p><p><strong>How to Cite</strong></p><p>Fibriana, F., &amp; Hadiyanti, L. N. (2016). Phylogenetic Relationships of Local Durian Species based on Morphological Characteristics and PCR-RFLP Analysis of the Ribosomal Internal Transcribed Spacer (ITS) DNA. <em>Biosaintifika: Journal of Biology &amp; Biology Education</em>, 8(3), 362-370. </p>

scholarly journals The trnL-F plastid DNA characters of three Poa pratensis (Kentucky bluegrass) varieties

2011 ◽  
Vol 51 (No. 2) ◽  
pp. 94-99 ◽  
Author(s):  
S.D. Stoneberg Holt ◽  
L. Horová ◽  
P. Bureš ◽  
J. Janeček ◽  
V. Černoch
Keyword(s):  
Poa Pratensis ◽  
Intergenic Spacer ◽  
Plastid Dna ◽  
Kentucky Bluegrass ◽  
Variety Identification ◽  
Trnl Intron ◽  
Major Band ◽  
F Region ◽  
Pcr Rflp

The characterization of crop cultivars (varieties) will come to depend increasingly on molecular characters in addition to traditional morphological and agronomic characters. Three cultivars of Kentucky bluegrass (Poa pratensis L.), developed by the Plant Breeding Station Hladk&eacute; Životice (PBHŽ), were characterized using sequences and PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) patterns from the non-coding plastid trnL-F region (trnL intron, 549 bp, and trnL-trnF intergenic spacer [IGS], 344 to 364 bp). These characters could be readily and repeatably determined not only for mature plants, but also for seedlings (less than 12 weeks old), which are difficult to distinguish morphologically. The method is quick and sensitive. When restricted with a combination of BsaJ I and Bsm I, cultivar Slezanka has one major band, Moravanka has two, and Harmonie has three. When restricted with Alu I, the heaviest band migrates most slowly for Slezanka. It is expected that many Kentucky bluegrass cultivars will share the same trnL-F sequence, so these characters alone are not sufficient for variety identification.

Baetis pentaphyllus sp. nov., a new species of mayfly (Ephemeroptera: Baetidae) from the Russian Far East

Zootaxa ◽  
2019 ◽  
Vol 4679 (2) ◽  
pp. 341-352
Author(s):  
TATIANA M. TIUNOVA ◽  
ALEXANDER A. SEMENCHENKO
Keyword(s):  
New Species ◽  
Sequence Data ◽  
Russian Far East ◽  
Far East ◽  
Species Group ◽  
Mitochondrial Coi ◽  
Sister Clade ◽  
Species Groups ◽  
Coi Sequences ◽  
A New Species

A new species, Baetis pentaphyllus sp. nov., is described on the basis of larvae from the Far East of Russia (type locality Bolshoi Garmakan River). Larvae of Baetis pentaphyllus sp. nov. may be distinguished from other Baetis species by the presence of only five pairs of tergalii on segments III–VII. The mitochondrial COI sequence obtained from the described species was compared with the data present in GeneBank and BOLD. The DNA barcodes allowed discrimination of B. pentaphyllus sp. nov. from other species of Baetis with available sequence data. The average interspecific K2P distances were 10–15%, which are values well above those associated with intraspecific variation. COI sequences as well as 36 morphological larval characters were analysed using Bayesian inference to relate the described species to the recognized species-groups of the Baetis genus. B. pentaphyllus sp. nov formed a sister clade to B. vardarensis + B. lutheri which belong to the Baetis lutheri species-group. 

scholarly journals Characterization of Race-Specific Interactions Among Isolates of Verticillium dahliae Pathogenic on Lettuce

2006 ◽  
Vol 96 (12) ◽  
pp. 1380-1387 ◽  
Author(s):  
Gary E. Vallad ◽  
Qing-Ming Qin ◽  
Rebecca Grube ◽  
Ryan J. Hayes ◽  
Krishna V. Subbarao
Keyword(s):  
Verticillium Dahliae ◽  
Field Experiments ◽  
Sequence Data ◽  
Intergenic Spacer ◽  
Distinct Subgroup ◽  
Race 1 ◽  
Race 2 ◽  
The 1960S ◽  
Significant Disease

Verticillium wilt, caused by Verticillium dahliae, poses a major threat to lettuce (Lactuca sativa) production in California. Incorporation of resistance into commercial lettuce cultivars offers the least expensive technique of sustaining production in infested areas. To test the breadth of the resistance identified in field experiments, a pair of susceptible (‘Salinas’ and ‘Sniper’) and resistant (‘La Brillante’ and ‘Little Gem’) lettuce cultivars were used as differentials and individually inoculated with 29 isolates of V. dahliae and two isolates of V. albo-atrum from several hosts, including lettuce, in replicated greenhouse experiments. The reactions of the four cultivars were determined based on the disease severity at maturity. None of the V. albo-atrum isolates or V. dahliae isolates from cruciferous hosts caused significant disease on lettuce. Both Salinas and Sniper were susceptible to many isolates of V. dahliae (21 of 23) from noncruciferous hosts, and the isolates varied in their overall virulence. However, of these, only three isolates caused significant disease on the resistant cvs. La Brillante and Little Gem. These three isolates also were distinct from the other V. dahliae isolates based on sequence data from the intergenic spacer (IGS) region of the nuclear ribosomal RNA gene, suggesting that they form a phylogenetically distinct subgroup that differs in virulence toward specific lettuce genotypes. Accordingly, isolates of V. dahliae virulent on all tested cultivars, including the resistant La Brillante and Little Gem, were designated as race 2, whereas those virulent only on the susceptible Salinas and Sniper were designated as race 1. Although a range of virulence among isolates has been described in other hosts, this is the first description of distinct virulence phenotypes in V. dahliae since a similar race structure was described in tomato in the 1960s.

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