scholarly journals Short communication: Dieback of rose caused by Acremonium sclerotigenum as a new causal agent of rose dieback in Iran

2016 ◽  
Vol 14 (4) ◽  
pp. e10SC03 ◽  
Author(s):  
Maryam Mirtalebi ◽  
Zia Banihashemi ◽  
Fatemeh Sabahi ◽  
Hamze Mafakheri
Keyword(s):  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Short Communication ◽  
Extended Period ◽  
Its Region ◽  
Causal Agent ◽  
Fars Province ◽  
Adverse Conditions ◽  
Brown Discoloration ◽  
Symptomatic Tissue

Severe dieback of rose has been recently observed in several rose greenhouses in Fars province of Iran. During 2014 and 2015, stems of rose plants showing yellow to brown discoloration and dieback were collected from rose greenhouses. Coniothyrium fuckelii, Botrytis cinerea and Acremonium were subsequently isolated from the margin between healthy and symptomatic tissue. B. cinerea and C. fuckelii isolates were similar to those previously reported for dieback of rose worldwide. Morphological and cultural characters along with molecular analysis based on partial sequences of the internal transcribed spacer (ITS) region of the ribosomal RNA genome allowed confirming the affiliation of the Acremonium isolates, corresponding to A. sclerotigenum as a new causal agent of rose dieback. To determine its pathogenicity on rose, Koch's postulates were fulfilled by stem inoculation of nine rose cultivars under greenhouse conditions. While A. sclerotigenum is considered as a soil-born pathogen, and produces sclerotia that are resistant to adverse conditions enables the fungus to survive extended period in soil, propagule trapping in our study revealed that conidia can become airborn, imply that an aerial phase, forms an important component of the disease cycle.

Detection of multiple infections by Monocystis strains in a single earthworm host using ribosomal internal transcribed spacer sequence variation

Parasitology ◽  
2009 ◽  
Vol 137 (1) ◽  
pp. 45-51 ◽  
Author(s):  
T. P. VELAVAN ◽  
H. SCHULENBURG ◽  
N. K. MICHIELS
Keyword(s):  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Sequence Variation ◽  
Lumbricus Terrestris ◽  
Its Region ◽  
Seminal Vesicles ◽  
Multiple Infections ◽  
Apicomplexan Parasites ◽  
Single Host ◽  
Ribosomal Cistron

SUMMARYMonocystis sp. are sporocyst-forming apicomplexan parasites common in seminal vesicles of the earthworm Lumbricus terrestris where they may account for temporary castration. This study describes the internal transcribed spacer (ITS) region of the ribosomal cistron of Monocystis sp. This region, including ITS-1, the 5·8S ribosomal RNA gene, and ITS-2, was PCR amplified, cloned, and sequenced for Monocystis sp. isolated from the seminal vesicles of several wild-caught L. terrestris. Our analysis revealed substantial polymorphisms, also within single host organisms, indicating intra-host diversity of parasites. These genetic markers are the first that allow distinction of Monocystis sp. genotypes, opening new avenues for the study of parasite diversity within and between hosts.

scholarly journals Botrytis squamosa - the causal agent of onion leaf blight in Bosnia and Herzegovina

2019 ◽  
Vol 34 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Brankica Tanovic ◽  
Milan Koscica ◽  
Jovana Hrustic ◽  
Milica Mihajlovic ◽  
Vojislav Trkulja ◽  
...  
Keyword(s):  
Bosnia And Herzegovina ◽  
Internal Transcribed Spacer ◽  
Abiotic Factors ◽  
Its Region ◽  
Causal Agent ◽  
Botrytis Squamosa ◽  
The Past ◽  
Leaf Spots ◽  
Necrotic Spots ◽  
Temperature And Growth

Over the past several decades, necrotic spots, lesions and blight symptoms have been observed on onion leaves in several locations in Bosnia and Herzegovina, where the crop is grown intensively. The type of symptoms indicated a possible infection with Botrytis squamosa, a widespread pathogen of onion. As symptoms of leaf spots and necrotic lesions can also be caused by some other biotic and abiotic factors, our research focused on identifying the causal agent of the observed symptoms. The pathogen was isolated from diseased tissue using standard phytopathological procedure and identified based on pathogenic and morphological features. Identification was confirmed by amplification and sequencing of the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). The influence of temperature and growth medium on mycelial growth rate of the isolates was also studied.

scholarly journals First Report of Rhizoctonia solani AG-4 on Epipremnum aureum in Buenos Aires, Argentina

Plant Disease ◽  
2001 ◽  
Vol 85 (1) ◽  
pp. 96-96 ◽  
Author(s):  
E. R. Wright ◽  
P. E. Grijalba ◽  
L. Gasoni
Keyword(s):  
Rhizoctonia Solani ◽  
Buenos Aires ◽  
Its Region ◽  
Anastomosis Group ◽  
Causal Agent ◽  
Basal Stem Rot ◽  
First Report ◽  
Brown Discoloration ◽  
Epipremnum Aureum ◽  
Petri Plate

Root and basal stem rot, blighting, and wilting have been observed on Epipremnum aureum (Linden ex André) plants in many nurseries in and near Buenos Aires since 1997. Infected stem tissues show an intense dark brown discoloration and water soaking near the stem base that eventually leads to plant death. To determine the causal agent of the disease, small pieces of diseased tissue were surface-sterilized for 2 min in 2% sodium hypochlorite and plated on potato-dextrose agar (PDA). Whitish colonies that eventually turned brown developed in 2 to 3 days at 22 to 24°C. Irregularly shaped sclerotia were observed. Isolates typical of Rhizoctonia solani Kuhn exhibited mycelia with branches inclined in the direction of growth, constricted at the point of union with the main hyphae, with a septum in the branch near the constriction. No telemorph was observed. Nuclei in living hyphal mats were stained directly on a microscope slide coated with water agar according to the method of Tu and Kimbrough (4) and were examined at 400× magnification. The cells were multinucleate. Anastomosis group was determined by using known tester isolates of Rhizoctonia spp. (3). Positive anastomosis was observed with tester strains of AG-4 HG-II. The polymerase chain reaction was performed according to the protocol of Boysen et al (1) in order to confirm the anastomosis group. Primers used for the amplification of the ITS region were ITSI and LROR. Amplification of the ITS region indicated lack of variation with AG-4 tester strain. The pathogenicity of the isolate was determined with the inoculum-layer technique (2), consisting of a 7-day-old petri plate culture of the pathogen in PDA that is removed from the dish and placed intact on the soil, 2 to 4 cm under the roots of 10 healthy plants. Some leaves of the plants were placed in contact with the inoculated substratum. For a control, PDA was placed under the roots of other plants. Plants were maintained at 22 to 24°C, with close-to-saturation humidity. After 6 to 10 days, symptoms were similar to those previously observed. Initially leaves that had been placed in contact with the substratum showed dark areas with a watersoaked area 2 to 3 cm in diameter. These lesions expanded over the entire leaf blade moving into the petioles and stems killing the plant. One hundred percent of inoculated plants were infected. Koch's postulates were satisfied after reisolating the fungus. The characteristics of the causal agent are those of multinucleate isolates of R. solani belonging to the anastomosis group AG-4 HG-II (3). This is the first report of R. solani causing disease on E. aureum in Argentina. References: (1) M. Boysen, M. Borja, C. Del Corral, O. Salazar, and V. Rubio. Curr. Genet. 29:174–181, 1996. (2) A. F. Schmitthenner and J. W. Hilty. Phytopathology 52:177–178, 1962. (3) B. Sneh, L. Burpee, and A. Ogoshi. 1991. Identification of Rhizoctonia Species. The American Phytopathological Society, St. Paul, MN. (4) C. C. Tu and J. W. Kimbrough. Mycologia 65:941–944, 1973.

Morphological and molecular identification of a new species of Cinereomyces (Polyporales, Basidiomycota) in southern China

Phytotaxa ◽  
2020 ◽  
Vol 459 (1) ◽  
pp. 51-60
Author(s):  
RUN-ZHI WANG ◽  
ZHI-YONG YUAN ◽  
CHANG-ZHI HAN ◽  
CHANG-LIN ZHAO
Keyword(s):  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Its Region ◽  
Fungal Species ◽  
Molecular Characteristics ◽  
Monophyletic Lineage ◽  
Inference Methods ◽  
A New Species

A new poroid wood-inhabiting fungal species, Cinereomyces fimbriatus sp. nov., is proposed based on morphological and molecular characteristics. The species is characterized by resupinate, brittle basidiomata with cream pore surface, a dimitic hyphal system with clamped generative hyphae, broad allantoid, hyaline, thin-walled, smooth basidiospores (3.6–4.6 × 0.8–1.1 µm). The internal transcribed spacer (ITS) region of nuclear ribosomal RNA gene sequences of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and bayesian inference methods. The phylogenetic analysis based on ITS sequences showed that C. fimbriatus formed a monophyletic lineage with strong supports (100% BS, 100% BT, 1.00 BPP) sister to C. lindbladii.

scholarly journals First Report of Brown Rot on Plum Caused by Monilia polystroma in China

Plant Disease ◽  
2010 ◽  
Vol 94 (4) ◽  
pp. 478-478 ◽  
Author(s):  
X. Q. Zhu ◽  
L. Y. Guo
Keyword(s):  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Morphological Characteristics ◽  
Brown Rot ◽  
Its Region ◽  
Apple Orchard ◽  
Monilinia Fructigena ◽  
First Report ◽  
Plant Pathol ◽  
Monilia Polystroma

In August 2008, mummies of dwarf sweet plum (Prunus aitianli) fruit covered with grayish, conidial tufts were found in an orchard in Mudanjiang City of Heilongjiang in China. Conidial masses were touched with a sterilized wire loop and streaked onto the surface of water agar (WA) plates. After incubating at 22 ± 2°C for 16 to 24 h, individual germinated spores were picked out with a sterilized scalpel blade under a microscope in a laminar flow cabinet, and transferred to potato dextrose agar (PDA) in petri dishes. Mycelium grew an average of 10.7 mm per day on PDA and formed a white-to-grayish colony with irregular, black stroma 12 days after incubation at 22 ± 2°C under 12-h light/12-h dark. The average size of stroma was 8.19 cm2 per petri dish 37 days after incubation in the dark. The conidia were one-celled, hyaline, lemon-shaped, 15.2 (10.8 to 18.9) × 10.9 (8.3 to 16.3) μm, and arranged in branched monilioid chains on inoculated apples. The PCR products of internal transcribed spacer (ITS) region 1 and 2 and 5.8S gene of the ribosomal RNA amplified with primers ITS1 and ITS4 was directly sequenced in both directions using the PCR primers. The sequence of the Monilia polystroma isolate (GenBank Accession No. GU067539) was identical to the reference isolate of M. polystroma (CBS102686), containing five nucleotides that distinguish it from Monilinia fructigena (1,3). The pathogen was identified as M. polystroma on the basis of morphological characteristics (3) and the sequence of internal transcribed spacer (ITS) region 1 and 2 and 5.8S gene of the ribosomal RNA. Pathogenicity was confirmed by inoculating surface-sterilized, mature plum and apple fruit wounded with a nail, with a mycelial plug (5 mm in diameter) of the fungus at each wound. Fruit treated with plain PDA plugs were used as a control. Inoculated fruits were placed in a sterilized moist chamber at room temperature (23 to 28°C). Fifteen plums and nine apples were used in each of two replicated tests. All inoculated fruit developed typical brown rot symptoms 4 days after inoculation, while the control fruit remained healthy. M. polystroma was reisolated from the inoculated fruit and identified by the above methods. M. polystroma was first reported on apple in Japan (3) and it was recently discovered in an apple orchard in Hungary (2). Although the occurrence of Monilinia fructicola, Monilinia laxa, and Monilinia fructigena (teleomorphs of the three Monilia spp.) in China have been documented, to our knowledge, this is the first report of the occurrence of M. polystroma in China. References: (1) C. E. Fulton et al. Eur. J. Plant Pathol. 105:495, 1999. (2) M. Petróczy and L. Palkovics. Eur. J. Plant Pathol. 125:343, 2009. (3) G. C. M. van Leeuwen et al. Mycol. Res. 106:444, 2002.

Hygrocybe rimosa (Hygrophoraceae, Agaricales), a new poisonous species from southern China

Phytotaxa ◽  
2021 ◽  
Vol 527 (4) ◽  
pp. 293-300
Author(s):  
CHAO-QUN WANG ◽  
MING ZHANG ◽  
HAI-JIAO LI ◽  
HAO HUANG ◽  
WANG-QIU DENG ◽  
...  
Keyword(s):  
Abdominal Pain ◽  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Southern China ◽  
Large Subunit ◽  
Its Region ◽  
Morphological Data ◽  
New Taxon

Hygrocybe rimosa, a new poisonous species belonging to subg. Hygrocybe, is described from southern China with both phylogenetic and morphological data. This species can cause nausea, vomiting, and abdominal pain. Morphologically, it is characterized by its orange to red and fibrillose pileus, irregularly split pileus margin, free, broad to ventricose, white lamellae, and subglobose to oblong basidiospores measuring (7)7.5–11 ×5–8(8.5) μm. Phylogenetically, analyses based on the internal transcribed spacer (ITS) region and the nuclear ribosomal RNA large subunit (LSU) indicate that H. rimosa is a member of subg. Hygrocybe. Ecologically, the new taxon usually grows in subtropical grasslands.

scholarly journals Evaluation of five regions as DNA barcodes for identification of Lepista species (Tricholomataceae, Basidiomycota) from China

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7307
Author(s):  
Siyu Wang ◽  
Hongbo Guo ◽  
JiaJia Li ◽  
Wei Li ◽  
Qin Wang ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
Internal Transcribed Spacer ◽  
Dna Barcode ◽  
Pcr Amplification ◽  
Intergenic Spacer ◽  
Its Region ◽  
Small Subunit ◽  
Dna Barcodes ◽  
Success Rates ◽  
Small Subunit Rdna

Background Distinguishing among species in the genus Lepista is difficult because of their similar morphologies. Methods To identify a suitable DNA barcode for identification of Lepista species, we assessed the following five regions: internal transcribed spacer (ITS), the intergenic spacer (IGS), nuclear ribosomal RNA subunit, mitochondrial small subunit rDNA, and tef1. A total of 134 sequences from 34 samples belong to eight Lepista species were analyzed. The utility of each region as a DNA barcode was assessed based on the success rates of its PCR amplification and sequencing, and on its intra- and inter-specific variations. Results The results indicated that the ITS region could distinguish all species tested. We therefore propose that the ITS region can be used as a DNA barcode for the genus Lepista. In addition, a phylogenetic tree based on the ITS region showed that the tested eight Lepista species, including two unrecognized species, formed eight separate and well-supported clades.

Infundibulicybe rufa sp. nov. (Tricholomataceae), a reddish brown species from southwestern China

Phytotaxa ◽  
2016 ◽  
Vol 266 (2) ◽  
pp. 134 ◽  
Author(s):  
QI ZHAO ◽  
YAN-JIA HAO ◽  
JIAN-KUI LIU ◽  
KEVIN D. HYDE ◽  
YANG-YANG CUI ◽  
...  
Keyword(s):  
Internal Transcribed Spacer ◽  
Phylogenetic Analyses ◽  
Biosphere Reserve ◽  
Its Region ◽  
Southwestern China ◽  
New Taxon ◽  
Line Drawings ◽  
Phylogenetic Placement ◽  
Molecular Phylogenetic ◽  
Pileus Surface

Infundibulicybe rufa sp. nov., is described from Jiuzhaigou Biosphere Reserve, southwestern China. It is characterized by the combination of the following characters: umbilicate to slightly infundibuliform, reddish brown pileus; decurrent, cream lamellae; cylindrical stipe concolorous with the pileus surface. Molecular phylogenetic analyses using the nuclear ribosomal internal transcribed spacer (ITS) region indicates that I. rufa is closely related to I. mediterranea and I. bresadolana. A description, line drawings, phylogenetic placement and comparison with allied taxa for the new taxon are presented.

Higher-level relationships among the eucalypts are resolved by ITS-sequence data

2002 ◽  
Vol 15 (1) ◽  
pp. 49 ◽  
Author(s):  
Dorothy A. Steane ◽  
Dean Nicolle ◽  
Gay E. McKinnon ◽  
René E. Vaillancourt ◽  
Brad M. Potts
Keyword(s):  
Internal Transcribed Spacer ◽  
Sequence Data ◽  
Its Region ◽  
Molecular Data ◽  
Nuclear Ribosomal Dna ◽  
Its Sequence ◽  
Phylogenetic Groups ◽  
Single Section ◽  
Western Australian ◽  
Genus Eucalyptus

This expanded survey of ITS sequences represents the largest analysis of molecular data ever attempted on Eucalyptus. Sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA were included in an analysis of 90 species of Eucalyptus s.s. and 28 species representing eight other genera (Allosyncarpia, Angophora, Arillastrum, Corymbia, Eucalyptopsis, Stockwellia, Lophostemon and Metrosideros). The results of the study indicate that Angophora and Corymbia form a well-supported clade that is highly differentiated from Eucalyptus s.s. Corymbia species are divided between two clades, one of which may be the sister to Angophora. Allosyncarpia, Arillastrum, Eucalyptopsis and ‘Stockwellia’ are also highly differentiated from Eucalyptus s.s. If the genus Eucalyptus is to be expanded to include Angophora and Corymbia(sensu Brooker 2000), ITS data suggest that Allosyncarpia, Eucalyptopsis, ‘Stockwellia’ and potentially Arillastrum should also be included in Eucalyptus s.l. The ITS data suggest that subg. Symphyomyrtus is paraphyletic and that subg. Minutifructus should be included within it. Within subg.Symphyomyrtus, only sect. Maidenaria appears to be monophyletic. Sections Adnataria and Dumaria are probably monophyletic; sections Exsertaria and Latoangulatae are very close and probably should be combined in a single section. Section Bisectae is polyphyletic and is divided into two distinct lineages. The phylogenetic groups depicted by ITS data are consistent with the frequency of natural inter-specific hybridisations as well as data from controlled crosses within subgenus Symphyomyrtus. The ITS data illustrate that subg. Idiogenes and western Australian monocalypts are early evolutionary lines relative to E. diversifolia, E. rubiginosa (monotypic subg. Primitiva) and the eastern monocalypts and that subg. Primitiva should be sunk into subg. Eucalyptus. Subgenus Eudesmia may be monophyletic, grouping with subgenera Idiogenes and Eucalyptus. Further work is required to confirm the phylogenetic positions of the monotypic subgenera Alveolata, Cruciformes, Acerosae and Cuboidea.

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