First report of downy mildew caused by Peronospora verbenae on verbena in the Czech Republic

Sweet basil (Ocimum basilicum L.) is an aromatic plant that is cultivated as a pot plant in greenhouses or in fields in the Czech Republic. The plants are intended for direct consumption or for drying. In April of 2012, the first large chlorotic from the middle necrotic spots occurred gradually on leaves of pot plants O. basilicum cv. Genovese in greenhouses in Central Bohemia. The characteristic gray to brown furry growth of downy mildew appeared on abaxial surfaces of leaves in the place of chlorotic spots within 3 to 4 days. The infested leaves fell off in the late stages of pathogenesis. The infestation gradually manifested itself in ever-younger plants and in July, cotyledons and possibly the first true leaves were already heavily infected and damaged and these plants rapidly died. The plant damage reached 80 to 100%, so it was necessary to stop growing the plants in the greenhouse at the end of July. The causal agent was isolated and identified as Peronospora belbahrii Thines by means of morphological and molecular characters (2,3). Conidiophores were hyaline, straight, monopodial, 280 to 460 μm, branched three to five times, ended with two slightly curved branchlets with a single conidia on each branchled tip. The longer branchlets measured 13 to 24 μm (average 18.2 μm), the shorter one 4 to 15 μm (average 9.7 μm). Conidia were rounded or slightly ovoid, from brownish to dark brownish, measured 22 to 31 × 20 to 28 μm (length/width ratio 1.2). A pathogen-specific sequence was detected with the help of the pathogen ITS rDNA specific primers in symptomatic leaves (1). DNA from plant tissues was isolated using the DNeasy plant Mini Kit (Qiagen, Germany) following the standard protocol. PCR was performed using KAPA2G Robust HotStar kit (Kapa Biosystems, United States) according to the conditions recommended in Belbahri et al. (1). The specific products were visualized by electrophoresis through 1.5% agarose gels. Leaves of 20-day-old potted plants O. basilicum ‘Genovese’ were inoculated by spraying with 5 × 105 conidia/ml of the pathogen. Each pot contained 10 plants. Sterilized distilled water was applied to control plants. Plants were covered with polyethylene bags during the entire incubation period to maintain high humidity, and kept at a temperature of 22 to 24°C. Typical disease symptoms appeared on leaves 5 to 9 days after inoculation. Control plants were symptomless. P. belbahrii was re-isolated from the lesions of inoculated plants, thus fulfilling Koch's postulates. Downy mildew on sweet basil was reported in countries in Africa, Europe, and South and North America (4). To our knowledge, this is the first report of downy mildew on sweet basil in the Czech Republic. References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) Y.-J. Choi et al. Mycol. Res. 113:1340, 2009. (3) M. Thines et al. Mycol. Res. 113:532, 2009. (4) C. A. Wyenandt et al. HortScience 45:1416, 2010.

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First Report of Buckwheat Downy Mildew Caused by Peronospora cf. ducometi in the Czech Republic

Plant Disease ◽

10.1094/pdis-01-15-0020-pdn ◽

2015 ◽

Vol 99 (8) ◽

pp. 1178 ◽

Cited By ~ 1

Author(s):

I. Petrželová ◽

M. Kitner ◽

M. Jemelková ◽

I. Doležalová

Keyword(s):

Czech Republic ◽

Downy Mildew ◽

The Czech Republic ◽

First Report

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First Report of Basil Downy Mildew Caused by Peronospora belbahrii in the Czech Republic

Plant Disease ◽

10.1094/pdis-06-14-0613-pdn ◽

2015 ◽

Vol 99 (3) ◽

pp. 418-418 ◽

Cited By ~ 3

Author(s):

I. Petrželová ◽

M. Kitner ◽

I. Doležalová ◽

V. Ondřej ◽

A. Lebeda

Keyword(s):

Czech Republic ◽

Downy Mildew ◽

Morphological Characteristics ◽

Its Region ◽

Width Ratio ◽

Natural Occurrence ◽

The Czech Republic ◽

First Report ◽

Sweet Basil ◽

The World

Sweet basil (Ocimum basilicum L.) is an annual aromatic and medicinal plant in the Lamiaceae that is originally native to India but is grown in warm regions all over the world. It is a popular culinary herb used fresh and dried, and is used in traditional folk medicine. In the Czech Republic, sweet basil is grown commercially in South Moravia or by home gardeners as a potted plant. In 2012, severe downy mildew was observed in a field of basil plants (cv. Dark Green) at the Crop Research Institute (CRI) in Olomouc, Czech Republic. Infected leaves each exhibited large, interveinal, chlorotic lesions, and violet-gray, fuzzy growth on the lower leaf surface. Within a few days, lesions turned necrotic and severely infected leaves dropped prematurely. Microscopic observations revealed hyaline conidiophores typical of Peronospora Corda, emerging from stomata. Conidiophores (n = 100) were usually 239.9 to 296.5 × 8.7 to 10.6 μm, straight, and were branched 4 or 5 times submonopodially at the upper ends. Ultimate branchlets (n = 100) were slightly curved and obtuse, with the longer branchlets usually 17.8 to 22.7 μm and the shorter branchlets 10.0 to 12.9 μm, and each bearing a single conidium. Conidia (n = 100) were olive-brown, mostly ellipsoidal to subglobose, and typically 29.0 to 31.0 × 23.2 to 25.4 μm, with a length/width ratio of 1.2 to 1.3. Oospores were not observed. Based on these morphological characteristics, the pathogen was identified as Peronospora belbahrii Thines (5). The specimen was deposited in a local herbarium at the CRI in Olomouc, as voucher PB-1. Genomic DNA was extracted from conidia, and the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) amplified with primers DC-6 (1) and LR-0 (4). A sequence was deposited in the NCBI database (GenBank Accession No. KJ960193). A BLAST search of the NCBI database revealed 99% identity to the deposited ITS sequences of P. belbahrii from basil and other host species (EU863410, FJ394334-7, GQ390794, GQ390795, HM462241, HM462242, HM486901, HQ702191, HQ730979, KC756923, KF419289, and KF419290). P. belbahrii was first described by Thines et al. (5) as a pathogen of sweet basil and coleus (Solenostemon scutellarioides), but can also infect Agastache spp. (2). There are many reports indicating the pathogen is spreading throughout the world (5). In Europe, chronologically, basil downy mildew has been reported from Italy, France, Switzerland, Germany, Hungary, and Cyprus (2,3,5). To our knowledge, this is the first report of natural occurrence of downy mildew on sweet basil in the Czech Republic. References: (1) D. E. L. Cooke et al. Fung. Genet. Biol. 30:17, 2000. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory, USDA ARS. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , 16 June 2014. (3) A. Garibaldi et al. Plant Dis. 89:683, 2005. (4) O. Spring et al. Eur. J. Plant Pathol. 114:309, 2006. (5) M. Thines et al. Mycol. Res. 113:532, 2009.

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First report of Cherry virus F infecting Japanese plum in Korea

Plant Disease ◽

10.1094/pdis-08-20-1725-pdn ◽

2020 ◽

Author(s):

Yeonhwa Jo ◽

Hoseong Choi ◽

Jin Kyong Cho ◽

Won Kyong Cho

Keyword(s):

Czech Republic ◽

High Throughput Sequencing ◽

Prunus Avium ◽

De Novo ◽

Protein Database ◽

Specific Primers ◽

The Czech Republic ◽

First Report ◽

Japanese Plum ◽

Leaf Spots

Cherry virus F (CVF) is a tentative member of the genus Fabavirus in the family Secoviridae, consisting of two RNA segments (Koloniuk et al. 2018). To date, CVF has been documented in only sweet cherry (Prunus avium) in the Czech Republic (Koloniuk et al. 2018), Canada, and Greece. In May 2014, we collected leaf samples from four symptomatic (leaf spots and dapple fruits) and two asymptomatic Japanese plum cultivars (Sun and Gadam) grown in an orchard in Hoengseong, South Korea, to identify viruses and viroids infecting plum trees. Total RNA from individual plum trees was extracted using two commercial kits: Fruit-mate for RNA Purification Kit (Takara, Shiga, Japan) and RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). We generated six mRNA libraries from the six different plum cultivars for RNA-sequencing using the TruSeq RNA Library Preparation Kit v2 (Illumina, CA, U.S.A.) as described previously (Jo et al. 2017). The mRNA libraries were paired-end (2 X 100 bp) sequenced with a HiSeq 2000 system (Macrogen, Seoul, Korea). The raw sequence reads were de novo assembled by Trinity program v. 2.8.6, with default parameters (Haas et al. 2013). The assembled contigs were subjected to BLASTX search against the non-redundant protein database in NCBI. Of the two asymptomatic cultivars, the transcriptome of asymptomatic plum cv. Gadam contained five contigs specific to CVF. Two and three contigs were specific to CVF RNA1 (2,571 reads, coverage 42.15%) and RNA2 (2,025 reads, coverage 53.04%), respectively. The size of these five contigs ranged from 241 to 5,986 bp. Contigs of 5,986 and 3,867 bp in length, referred to as CVF isolate Gadam RNA1 (GenBank MN896996) and RNA2 (GenBank MN896995), respectively, were subjected to BLASTP search against NCBI’s non-redundant protein database. The results showed that the polyprotein sequences of RNA1 and RNA2 shared 95.3% and 93.11% amino acid identities with isolates SwC-H_1a from the Czech Republic (GenBank acc. no. AWB36326) and Stac-3B_c8 from Canada (AZZ10055), respectively. To confirm the infection of CVF in cv. Gadam, RT-PCR was conducted using CVF RNA1-specific primers designed based on the CVF reference genome sequences (MH998210 and MH998216), including 5’-CCACCAAATAGGCAAGAGGTCAC-3’ (position 3190–3212) and 5’-CACAATCACCATCAATGGTCTCTGC-3’ (position 3742–3766), and CVF RNA2-specific primers, including 5’-CTGCTTTATGATGCTAGACATCAAGATG-3’ (position 1015–1042) and 5’-ACAATAGGCATGCTCATCTCAACCTC-3’ (position 1594–1619). We amplified 577-bp RNA1-specific and 605-bp RNA2-specific amplicons that were cloned and then performed Sanger sequencing. Sequencing of the cloned amplicons for isolate Gadam RNA1 (GenBank MN896993) and RNA2 (GenBank MN896994) revealed values of 99.48% and 99.17% nucleotide identity to that of RNA1 and RNA2 determined by high-throughput sequencing, respectively. Additionally, we tested five plants for each of the six plum cultivars grown in the same orchard. The detection of CVF was carried out through PCR using the primers and protocol described above. Of the 30 trees, CVF was detected in three trees of cv. Gadam by both primer pairs. To our knowledge, this is the first report of CVF infecting Japanese plum and the first report of the virus in Korea. However, its prevalence in other Prunus species, including apricot, European plum, and peach, should be further elucidated.

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First Report of Colletotrichum acutatum on Tomato and Apple Fruits in the Czech Republic

Plant Disease ◽

10.1094/pdis-10-11-0849-pdn ◽

2012 ◽

Vol 96 (5) ◽

pp. 769-769 ◽

Cited By ~ 4

Author(s):

J. Víchová ◽

B. Staňková ◽

R. Pokorný

Keyword(s):

Czech Republic ◽

Tomato Fruit ◽

Colletotrichum Acutatum ◽

Distilled Water ◽

Species Determination ◽

Specific Primers ◽

The Czech Republic ◽

First Report ◽

Pcr Products ◽

Apple Fruits

Apple (Malus domestica Borkh.) is a fruit traditionally grown in the Czech Republic, and tomatoes (Solanum lycopersicum Mill.), too, are widely raised in this region. Colletotrichum acutatum J. H. Simmonds is a polyphagous fungal plant pathogen. Earlier, this pathogen caused disease on strawberry in the Czech Republic (2), and now it has become an important pathogen on safflower (4). During the 2010 harvest, anthracnose symptoms were noticed on the fruits of apple and tomato. Infected apples fruits (localities Velká Bíteš and Znojmo) and tomatoes (localities Velká Bíteš and Žabčice) were collected. Typical symptoms on fruit surfaces were round, brown, shriveled and sunken spots, 1.2 to 2.0 cm, with orange conidial masses appearing on the spots. A fungus was isolated from each host on potato dextrose agar and cultured at 25 ± 2°C for 10 days. Mycelium was superficial, partly immersed, and white to gray with occurrence of orange conidial masses. Conidia of the tomato and apple isolates were colorless and fusiform. The size of conidia from the apple and tomato isolates, respectively, ranged from 11 to 15 × 2.5 to 3.5 μm and 11 to 16 × 2.5 to 4 μm. Morphological characteristics suggested that the isolated fungi was a Colletotrichum sp. To fulfill Koch's postulates, healthy tomato and apple fruits were disinfected with 3% sodium hypochlorite for 2 min and rinsed in sterile distilled water. Fruits were pinpricked with a sterile needle and 10 μl of a spore suspension (1 × 105 conidia ml–1) was inoculated by pipetting into the wound. Control fruits were treated with sterile distilled water. The fruits were transferred to a growth cabinet and maintained at a temperature of 25 ± 2°C, relative humidity of 70 ± 5%, and a photoperiod of 12 h. Similar disease symptoms as in the collected fruits were observed on tomato fruits at 7 days and apple fruits at 20 days after inoculation, while no symptoms appeared on control fruits. The pathogen was reisolated from infected fruits. Species determination of the isolates was confirmed by PCR. Specific primers designed in region ITS1, the 5.8S RNA gene, and region ITS2 of the pathogen DNA were selected. Specific primers CaInt2 and ITS4 were used to identify C. acutatum (3), and primers CgInt and ITS4 were used to determine C. gloeosporioides isolate CCM 177 (1), which was used as a control. Our isolates yielded PCR products (490 bp) only with primers designed for C. acutatum. The C. gloeosporioides isolate yielded a PCR product (450 bp) only with CgInt and ITS4 primers. PCR products were sequenced and identified with the BLAST program. The sequence of the tomato fruit isolate (Accession No. JN676199) and apple fruit isolate (Accession No. JN676198) matched with 100% similarity to the C. acutatum sequences in GenBank. The control isolate of C. gloeosporioides matched 100% to sequences AJ749682 and AJ749692. To our knowledge, this is the first report of C. acutatum on tomato and apple fruits in the Czech Republic. This pathogen can endanger the production and storage of apples and tomatoes in this region. References: (1) P. R. Mills et al. FEMS Microbiol. Lett. 98:137, 1992. (2) D. Novotný et al. Plant Dis. 91:1516, 2007. (3) S. Sreenivasaprasad et al. Plant Pathol. 45:650, 1996. (4) J. Víchová et al. Plant Dis. 95:79, 2011.

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Occurrence and distribution of mating types A1 and A2 of Phytophthora infestans (Mont.) de Bary in the Czech Republic

Plant Protection Science ◽

10.17221/2697-pps ◽

2010 ◽

Vol 42 (No. 2) ◽

pp. 41-48 ◽

Cited By ~ 7

Author(s):

J. Mazáková ◽

V. Táborský ◽

M. Zouhar ◽

P. Ryšánek ◽

E. Hausvater ◽

...

Keyword(s):

Czech Republic ◽

Phytophthora Infestans ◽

Mating Type ◽

Mating Types ◽

Pcr Markers ◽

The Czech Republic ◽

First Report

A total of 199 <i>Phytophthora infestans</i> isolates were obtained from leaves, tubers and fruits of infected crops of potato and tomato in different regions of the Czech Republic in 2003, 2004 and 2005. They were analysed for mating type using the conventional pairing assay and PCR markers; 107 isolates were of A1 and 92 of A2 mating type. No self-fertile isolate was found. Our study is the first report of the presence and distribution of the A2 mating type of <i>P. infestans</i> in the Czech Republic. The co-existence of the two mating types may enable the pathogen to reproduce sexually, thus enhancing the diversity of its population countrywide.

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Occurrence of rust disease caused by Puccinia oxalidis on Oxalis triangularis in the Czech Republic – Short Communication

Plant Protection Science ◽

10.17221/19/2013-pps ◽

2014 ◽

Vol 50 (No. 1) ◽

pp. 17-18

Author(s):

I. Šafránková

Keyword(s):

Czech Republic ◽

Leaf Spot ◽

Short Communication ◽

Rust Disease ◽

The Czech Republic ◽

First Report ◽

Microscopic Features

This is the first report of Puccinia oxalidis causing leaf spot diseases on ornamental Oxalis triangularis subsp. papilionaceae cv. Atropurpurea in Moravia, Czech Republic. The macroscopic symptoms and microscopic features are described.

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The first report of authochthonous dirofilariosis in dogs in the Czech Republic

Helminthologia ◽

10.2478/s11687-006-0046-5 ◽

2006 ◽

Vol 43 (4) ◽

pp. 242-245 ◽

Cited By ~ 36

Author(s):

Z. Svobodová ◽

V. Svobodová ◽

C. Genchi ◽

P. Forejtek

Keyword(s):

Czech Republic ◽

Acid Phosphatase ◽

Adult Female ◽

Peripheral Blood ◽

Dirofilaria Immitis ◽

The Czech Republic ◽

First Report ◽

Imported Infection ◽

Circulating Antigens ◽

Commercial Kit

AbstractIn the Czech Republic, canine dirofilarial infection (Dirofilaria immitis and D. repens) is usually diagnosed in dogs coming from endemic areas and as such has been considered an imported infection. Here, 77 dogs that had never travelled abroad from the Břeclav area, close to Slovak border, were tested for Dirofilaria spp. infection. The presence of microfilaria in peripheral blood was detected by Knott test. Microfilariae were further examined by acid phosphatase staining and molecular methods (PCR). The presence of adult female D. immitis circulating antigens in blood was assessed by a commercial kit (PetChek, IDEXX Laboratories, Portland, USA). Microfilariae were detected in 7 (9 %) out of the 77 animals by the Knott test. The result of the acid phosphatase staining and PCR for all seven samples agreed with Dirofilaria repens species. Other five dogs of the 77 sera (6.5 %) sampled were serologically positive for circulating D. immitis antigens. No D. immitis microfilariae were found in these five dogs. D. repens positive dogs were negative on the ELISA for D. immitis. This is the first report of autochthonous cases of heart-worm disease and subcutaneous dirofilariosis in dogs in the Czech Republic.

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