János Ágoston

57211473871

Publications - 14

Identification of a novel pathogen of the glacial relict Drosera rotundifolia and the impact of the fungus on the conservation of the plant and its habitat

László Palkovics Mátyás Szépligeti János Ágoston A. Tóth L. Szendrei

Publication Name: Fungal Biology

Publication Date: 2025-10-01

Volume: 129

Issue: 6

Page Range: Unknown

Description:

Round-leaved sundew (Drosera rotundifolia L.) is a protected glacial relict plant inhabiting Sphagnum bogs, which are endangered habitats in Hungary. In 2020 and 2021 greyish mycelium growth was observed on the hibernacula of D. rotundifolia in Czech Republic, Germany and Hungary. Samples have been collected in possession of the required permits. The fungus was isolated and identified with classical and molecular methods. Koch's postulates were fulfilled. The novel pathogen was identified as the highly polyphagous Botrytis cinerea in each sample. Simultaneously, field assessments of wild Hungarian populations were carried out. Throughout the survey of three different Hungarian collection sites, altogether 207 hibernacula were carefully examined for gray mold symptoms. Interestingly, only plants grown on milled peat substrate were affected by the pathogen. The antifungal and antimicrobial properties of Sphagnum mosses have been reported by other researchers, which could aid in the protection of D. rotundifolia hibernacula. These results indicate that live Sphagnum moss is a better substrate for this species than milled peat, both for commercial production and for in situ conservation. This information can be vital to the survival and conservation of this species. Sphagnum bogs may protect and allow the expansion and re-establishment of D. rotundifolia.

Open Access: Yes

DOI: 10.1016/j.funbio.2025.101614

Investigation of viral diseases of garlic (Allium sativum L.), new primers for RT-PCR detection and diversity of garlic viruses in Hungary

László Palkovics János Ágoston Ádám Koczor János Ádám Katalin Salánki

Publication Name: Physiological and Molecular Plant Pathology

Publication Date: 2024-11-01

Volume: 134

Issue: Unknown

Page Range: Unknown

Description:

The study investigated the presence of potyviruses, carlaviruses, and allexiviruses in garlic samples, highlighting the impact of these viruses on garlic cultivation. No virus-free garlic was identified, with infections from at least one virus species observed in all samples. Notably, LYSV was detected in one sample, emphasizing the critical need for certified propagating material. Our study revealed the predominance of allexiviruses, particularly GarVD. Interestingly, no mixed carlavirus infections were detected. The results underline the risk of virus complexes, particularly when potyvirus infections occur alongside carla- or allexiviruses, exacerbating yield losses. The new primers we designed were successfully used, the usability of certain primers from earlier research has been confirmed, and new potential applications have been identified for some primers. In our study we have molecularly identified LYSV, GCLV, SLV, GarVB, GarVC and GarVD infected samples from Hungary, the presence of LYSV was confirmed with ELISA as well.

Open Access: Yes

DOI: 10.1016/j.pmpp.2024.102394

Biology, phylogenetic and evolutionary relations of Tradescantia mild mosaic virus isolates from Hungary

László Palkovics Réka Sáray János Ágoston Dóra Pinczés Asztéria Almási Katalin Salánki

Publication Name: Journal of Plant Pathology

Publication Date: 2024-08-01

Volume: 106

Issue: 3

Page Range: 1369-1374

Description:

In Western Transdanubia in 2018 and in Central-Hungary in 2022 spiderwort plants showed flower breaking symptoms and mild mosaic on the foliage, which indicated a potential virus infection. One gram of symptomatic leaf sample was collected at both locations. Potyvirus-specific ELISA tests demonstrated potyvirus infection. To identify the virus species, potyvirus-specific RT-PCR was carried out on the samples. In both samples specific PCR products were detected and cloned into pGEM®-T Easy vector. The nucleotide sequences of the inserts were determined by Sanger sequencing. BLASTn searches on the complete coat protein region of both isolates demonstrated more than 99.87% identity with Tradescantia mild mosaic virus (TraMMV; accession number OL584375). Koch postulates were fulfilled by sap inoculating seed grown spiderwort plants. Phylogenetic analyses of the TraMMV coat protein sequences revealed two distinct evolutionary lineages: a tropical subgroup with at least 97.84% identity within the group and temperate subgroup with at least 98.97% identity within the group. One major difference between the subgroups was in the triplet responsible for vector transmission. The isolates belonging to the tropical subgroup had DAG triplets, while the temperate subgroup had NAG triplets. The difference in the triplets could be caused by natural diversification, directional selection or disruptive selection. License: CC BY-NC-ND

Open Access: Yes

DOI: 10.1007/s42161-024-01661-9

A Species-Specific PCR Differentiates Two Causal Agents of Hazel Powdery Mildew and Reveals the Occurrence of Erysiphe corylacearum

Márk Z. Németh János Ágoston Klementina Kalmár Katalin Borostyán Éva Preininger Orsolya Molnár

Publication Name: Horticulturae

Publication Date: 2024-07-01

Volume: 10

Issue: 7

Page Range: Unknown

Description:

The demand for common hazel (Corylus avellana) fruit increases constantly. Powdery mildew (PM) on hazels in Hungary and throughout Europe was previously caused mainly by Phyllactinia guttata. However, less than a decade ago, another fungus of Asian origin, Erysiphe corylacearum, appeared on hazels in Europe, including Hungary. Our investigation aimed to develop a species-specific PCR (ssPCR) to aid the identification of P. guttata and E. corylacearum, and to assess the presence of the latter, non-native fungus in Hungary. For this study, 59 samples were collected from Hungary between 2021 and 2023. The chasmothecial morphology of the PM fungi was observed, and the internal transcribed spacer (ITS) of ribosomal DNA was sequenced in representative samples. Morphological analysis distinguished two types of chasmothecia. Parts of the chasmothecia, typical of P. guttata, were flattened and spherical with bristle-like appendages, while other chasmothecia, characteristic of E. corylacearum, were distinctly smaller, bearing appendages with branched apices. Sequence data also verified the presence of P. guttata and E. corylacearum in our samples. The developed ssPCR revealed that E. corylacearum was present in more than three-quarters of the samples, more than a quarter of the samples contained both fungi and about one-fifth carried solely P. guttata. The alien fungus E. corylacearum was found in all but one of the sampled regions and was found on C. avellana and also on C. colurna. Erysiphe corylacearum spreads rapidly and can be considered an invasive pathogen. Its practical importance lies in its ability to infect hazelnuts, potentially causing economic losses. Our ssPCR ensures accurate and quick identification of the fungus, which is essential for effective plant protection.

Open Access: Yes

DOI: 10.3390/horticulturae10070763

Powdery mildew of ash trees caused by the non-native Erysiphe salmonii in Hungary

Alexandra Pintye Diána Seress Márk Z. Németh János Ágoston Anita Z. Soós Orsolya Molnár

Publication Name: Journal of Plant Diseases and Protection

Publication Date: 2024-06-01

Volume: 131

Issue: 3

Page Range: 1093-1097

Description:

Fraxinus ornus and F. excelsior are naturally occurring woodland trees and widely cultivated ornamental plants in Hungary. Leaves with powdery mildew symptoms observed unusually on adaxial side of leaves of F. ornus and F. excelsior were collected from two locations in Hungary. We identified the causing fungi based on their morphological characteristics and molecular phylogenetic analysis. Numerous chasmothecia were found on a part of the samples, which were spherical, 83–120 µm in diameter, and the apices of the appendages uncinated or spirally curved. Anamorphs were characterized by conidiophores developing conidia singly, and by hyphae with lobed appressoria, characteristic of Erysiphe spp. The internal transcribed spacer region of the nrDNA was amplified, and the BLAST searches showed 100% similarity with Erysiphe salmonii sequences in GenBank. In the phylogenetic analysis the sequences of the Hungarian samples grouped in one clade with the sequences of other E. salmonii specimens collected in Central and Eastern Europe and Asia. This is the first report of the non-native E. salmonii causing powdery mildew on Fraxinus sp. in Hungary.

Open Access: Yes

DOI: 10.1007/s41348-023-00854-1

First Report of Saffron Latent Virus in Crocus sativus from Hungary

László Palkovics Réka Sáray János Ágoston Dóra Pinczés Asztéria Almási Katalin Salánki

Publication Name: Plant Disease

Publication Date: 2024-02-01

Volume: 108

Issue: 2

Page Range: 540

Description:

No description provided

Open Access: Yes

DOI: 10.1094/PDIS-09-23-1765-PDN

First report of Rhodococcus fascians causing leafy gall on Iberis sempervirens in Hungary

László Palkovics Zoltán Bozsó András Künstler János Ágoston Judit Kolozsváriné Nagy Ildikó Schwarczinger Dénes Dlauchy Lóránt Király József Fodor

Publication Name: Phytopathologia Mediterranea

Publication Date: 2024-01-01

Volume: 63

Issue: 3

Page Range: 465-473

Description:

In spring of 2023, leafy gall symptoms were detected on plants of evergreen candytuft (Iberis sempervirens ‘Pink Ice’) in Hungary. Bacteria isolated from gall-like tissues of short, stunted shoots, and showing a characteristic appearance on selective culture media were investigated using bacteriological and molecular methods, and phylogenetic analysis. Nucleotide sequences of the 16S rRNA gene, fasD and vicA genes were determined. Pathogenicity of selected isolates was confirmed on garden pea (Pisum sativum ‘Tristar’). Characterization of the investigated isolates indicated the presence of Rhodococcus fascians in I. sempervirens. This is the first report identifying the causal agent of leafy gall from this plant in Hungary.

Open Access: Yes

DOI: 10.36253/phyto-15357

First Report of 'Candidatus Phytoplasma asteris' Associated with Cyclamen Little Leaf in Hungary

János Ágoston Orsolya Viczián Emese Mergenthaler József Fodor

Publication Name: Plant Disease

Publication Date: 2023-08-01

Volume: 107

Issue: 8

Page Range: 2515

Description:

No description provided

Open Access: Yes

DOI: 10.1094/PDIS-12-22-2870-PDN

First report of a ‘Candidatus Phytoplasma asteris’-related strain (16SrI-B) associated with three Sempervivum cultivars in Hungary

János Ágoston Orsolya Viczián Emese Mergenthaler József Fodor

Publication Name: New Disease Reports

Publication Date: 2023-07-01

Volume: 48

Issue: 1

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: 10.1002/ndr2.12199

First Report of Meadow Saffron Breaking Virus on Wild Colchicum autumnale from a Strictly Protected Natura2000 Site at a Hungarian National Park

László Palkovics Réka Sáray János Ágoston Dóra Pinczés Asztéria Almási Katalin Salánki

Publication Name: Plant Disease

Publication Date: 2023-06-01

Volume: 107

Issue: 6

Page Range: 1955

Description:

No description provided

Open Access: Yes

DOI: 10.1094/PDIS-08-22-1787-PDN

Thalia dealbata, a new host of sugarcane mosaic virus

László Palkovics Réka Sáray János Ágoston Dóra Pinczés Asztéria Almási Katalin Salánki

Publication Name: Journal of Plant Pathology

Publication Date: 2023-05-01

Volume: 105

Issue: 2

Page Range: 587-588

Description:

No description provided

Open Access: Yes

DOI: 10.1007/s42161-022-01295-9

Detection and molecular identification of 'Candidatus Phytoplasma asteris' associated with muscari virescence of three grape hyacinth species

János Ágoston Orsolya Viczián Emese Mergenthaler József Fodor

Publication Name: Plant Protection Science

Publication Date: 2023-01-01

Volume: 59

Issue: 4

Page Range: 389-393

Description:

Grape hyacinths are popular perennial, flowering bulbous plants. In 2018, 2019, and 2020, some plants of three Muscari species showed symptoms similar to those associated with phytoplasma infection in commercial ornamental gardens in Hungary. Symptoms included virescence of flowers and yellowing of leaves. Symptomatic and asymptomatic Muscari plants were sampled at two locations to detect and identify the pathogens involved. Total DNA was extracted from the plants and used as a template in polymerase chain reaction assays to amplify 16S rRNA gene sequences and housekeeping genes (tuf, secY) with phytoplasma-specific primers. The resulting PCR products from symptomatic plants were cloned and sequenced bidirectionally. Homology searching of the obtained sequences against the GenBank database indicated the presence of 'Candidatus Phytoplasma asteris' in the three Muscari species. This is the first report worldwide of C. P. asteris phytoplasma infecting M. botryoides and M. comosum, and its first identification in M. armeniacum in Hungary.

Open Access: Yes

DOI: 10.17221/70/2023-PPS

Detection of ‘Candidatus Phythoplasma prunorum’ in Apricot Trees and its Associated Psyllid Samples

Márta Ladányi M. Petróczy László Palkovics Béla Pénzes Géza Nagy László Sándor Koncz János Ágoston Piroska Gyócsi József Fail

Publication Name: Agronomy

Publication Date: 2023-01-01

Volume: 13

Issue: 1

Page Range: Unknown

Description:

‘Candidatus Phytoplasma prunorum’ is causing ever increasing economic losses through the decline of apricot trees in European countries, e.g., Hungary. In this study, the pathogen was identified from plant tissues and insects by nested-PCR. The insect species were identified via morphology and molecular methods. The incidence of the pathogen was 29.6% in randomly selected apricot trees. Most of the infected trees with symptoms died within a year. These results show that phytoplasma is significantly present and causes damage in the investigated plantations. The only known insect vector of this phytoplasma is the plum psyllid, Cacopsylla pruni, which was regularly encountered in the sampled apricot orchards and in their surroundings. In a two-year study, several adults among the sampled specimens were observed to be infected by the pathogen. This observation further confirms the role of the plum psyllid in vectoring the phytoplasma. All the sampled plum psyllid adults belonged to the ‘B’ biotype. Besides C. pruni, Cacopsylla crataegi was abundant in the samples. Several adults of the latter species were also infected by the pathogen ‘Ca. Phytoplasma prunorum’. The rates of occurrence of this phytoplasma in male and female adults of the two psyllid species appeared to be similar. The examined C. crataegi individuals showed genetic differences from each other and from specimens included in a previous investigation.

Open Access: Yes

DOI: 10.3390/agronomy13010199

Sternbergia lutea, a new host of Narcissus late season yellows virus

László Palkovics János Ágoston Asztéria Almási Katalin Salánki

Publication Name: Phytopathologia Mediterranea

Publication Date: 2021-01-01

Volume: 60

Issue: 3

Page Range: 403-407

Description:

In autumn 2017, autumn daffodil plants with yellow-green stripes on the leaves were observed at a botanical garden in Budapest, Hungary. Indicator plants wereinoculated, but symptoms did not develop. RT-PCR tests of the indicator plants werealso negative for the viruses. Potyvirus specific ACP-ELISA and RT-PCR were carriedout on the symptomatic S. lutea leaf samples. RT-PCR with universal potyvirusprimers resulted in one, approx. 1700 base pair PCR product. Phylogenetic analysis ofthe nucleotide sequence of the coat protein demonstrated 98.78-99.51% identity withthree Japanese isolates of Narcissus late season yellows virus. While unidentified potyvirusinfection of autumn daffodil has been previously reported, sequence data havenot been published. Therefore, this is the first report of Sternbergia lutea as a host ofNarcissus late season yellows virus

Open Access: Yes

DOI: 10.36253/phyto-12709