Authors:G. Koncz, P. Török, M. Papp, G. Matus, and B. Tóthmérész
Intensification of land use in the last few decades resulted in an increased rate of fragmentation of natural forest habitats. With decreased patch size but increased total borderline length the influence of the surroundings also increased. The extent of influence is especially crucial where the forest stands are adjacent to agricultural lands. We studied the vegetation (cover) and seed bank (soil samples, seedling emergence) along adjacent stands of an abandoned vineyard and edge and interior of an oak forest community (Quercetum petraeae-cerris) widespread in Central-Europe, using five transects (16 m2 plots along each transect). We asked the following questions: (i) How do vegetation and seed bank composition differ between the vineyard and forest interior and (ii) which weeds are able to penetrate into the forest herbaceous understorey vegetation and seed banks from the vineyard? In total, 15 phanaerophytes and 147 herbs were detected. Negatively associated with canopy shading, herb cover proved the lowest in the forest inferior. Few weeds and other ruderals recorded in vineyard penetrated into the forest interior. Mean seed density decreased one order of magnitude from the vineyard to the forest interior (from 20,831 to 2,159 seed/m2). The seed banks of the abandoned vineyard and edge and forest interior were dominated by ruderals, but decreasing proportion of weeds was detected from the vineyard to the forest interior. Characteristic forest herbs possessed at most sparse seed banks. Our results suggest that high canopy cover mitigates the negative impact of surrounding weedy vegetation on the forest herb layer. Therefore, the effect of surroundings is detectable mostly in the seed banks. We can assume that the formation of an increased ruderal herb cover can be foreseen if canopy opens, because the local propagule sources of forest species are missing from vegetation and soil seed banks.
Authors:Enikő Vida, Orsolya Valkó, A. Kelemen, P. Török, B. Deák, T. Miglécz, Sz. Lengyel, and B. Tóthmérész
We studied the early vegetation dynamics in former croplands (sunflower and cereal fields) sown with a low-diversity seed mixture (composed of 2 native grass species) in Egyek-Pusztakócs, Hortobágy National Park, East-Hungary. The percentage cover of vascular plants was recorded in 4 permanent plots per field on 7 restored fields between 2006 and 2009. Ten aboveground biomass samples per field were also collected in June in each year. We addressed two questions: (i) How do seed sowing and annual mowing affect the species richness, biomass and cover of weeds? (ii) How fast does the cover of sown grasses develop after seed sowing? Weedy species were characteristic in the first year after sowing. In the second and third year their cover and species richness decreased. From the second year onwards the cover of perennial grasses increased. Spontaneously immigrating species characteristic to the reference grasslands were also detected with low cover scores. Short-lived weeds were suppressed as their cover and biomass significantly decreased during the study. The amount of litter and sown grass biomass increased progressively. However, perennial weed cover, especially the cover of Cirsium arvense increased substantially. Our results suggest that grassland vegetation can be recovered by sowing low diversity mixtures followed up by yearly mowing. Suppression of perennial weed cover needs more frequent mowing (multiple times a year) or grazing.
Authors:G. Koncz, Mária Papp, P. Török, Zs. Kotroczó, Zs. Krakomperger, G. Matus, and B. Tóthmérész
We studied the potential role of seed bank in the dynamics of the understorey in a turkey oak-sessile oak forest (Querceteum petraeae-cerris) in Hungary. We used long-term records of the herb layer (1973–2006) and the seed bank composition of 2006 to assess the role of seed bank in the regeneration of herb layer. The total cover of herb layer decreased from 22% (1973) to 6% (1988), and remained low (<10%) till 2006; coinciding with the increasing cover of secondary canopy dominated by Acer campestre. We found a low density seed bank (ca. 1300 seeds/m2). Altogether 33 species were germinated from the soil samples. A few generalist weed species composed the majority of seed bank. It was possible to assign a seed bank type for 19 species; 14 species out of 19 was long-term persistent. We found that the characteristic perennial forest herbs and grasses had only sparse seed bank. The Jaccard similarity between vegetation and seed bank was low (<30%). Our results suggest that the continuous establishment of forest herbs are not based on local persistent seed bank; it should be based on vegetative spreading and/or seed rain.
Authors:P. Török, T. Miglécz, O. Valkó, K. Tóth, A. Kelemen, Á.-J. Albert, G. Matus, A. Molnár V, E. Ruprecht, L. Papp, B. Deák, O. Horváth, A. Takács, B. Hüse, and B. Tóthmérész
In the present paper we report original thousand-seed weight data for the flora of the Pannonian Basin. Our goal was to demonstrate the usefulness of seed weight databases by analysing seed weight data in relation to social behaviour types and life forms. We specifically asked the following questions: (i) how the seed weights are related to social behaviour type categories; (ii) how the life form of the species influences seed weight differences between respective social behaviour types? Own weight measurements are provided for 1,405 taxa; and for 187 taxa we published seed weight data for the first time: these were mostly endemics, orchids and/or species with Pontic, Caspian or continental distribution. Several taxonomic or functional groups are underrepresented in our database, like aquatic plants, rare arable weeds and sub-Mediterranean species. Problematic taxa, some difficult-to-harvest species or species with low seed production and cultivated adventives are also underrepresented. We found that the plant strategies expressed by social behaviour types were significantly different in terms of seed weights. The lowest seed weight scores were found for natural pioneers, whereas the highest ones were found for adventives and introduced cultivated plants. Short-lived herbaceous species had significantly higher seed weight scores than herbaceous perennials. No significant differences were found between specialists and generalists within the stress tolerant group. We found that short-lived graminoids possess heavier seeds than perennial graminoids, perennial and annual forbs. Naturalness scores were negatively correlated with seed weights. Our findings showed that seed collections and databases are not only for storing plant material and seed weight data, but can be effectively used for understanding ecological trends and testing plant trait-based hypotheses. Even the identified gaps underline the necessity of further seed collection and measurements.
Authors:B. Tóth, O. Török, É. Kótai, M. Varga, É. Toldiné Tóth, X. Pálfi, E. Háfra, J. Varga, J. Téren, and Á. Mesterházy
Aspergillus and Penicillium species and their mycotoxins, including aflatoxins, ochratoxins, fumonisins and patulin, are frequently encountered on cereal products. The occurrence of these species and their mycotoxins on maize was investigated in Hungary after harvest in two consecutive years. Surface-sterilized cereal seeds were placed on selective media, and the isolated fungal strains were identified using morphological methods. In 2010 and 2011, 81.94% and 14.33%, respectively, of the samples were found to be contaminated with potentially toxigenic isolates. The species identification of selected isolates was carried out using sequence-based methods. Several Aspergillus flavus isolates were identified, which are potential aflatoxin producers. Other mycotoxinproducing species were also isolated, including black Aspergilli, which potentially produce ochratoxins and fumonisins, and A. clavatus, which produces patulin. In 2010 a large number of Penicillium species occurred in the samples, producing a wide range of mycotoxins. The mycotoxin content of the samples was analysed using the ELISA and HPLC techniques. Aflatoxins were not detected in any of the samples, while ochratoxins and fumonisins were successfully identified in some of the maize seeds.
Authors:P. Török, E. Tóth, K. Tóth, O. Valkó, B. Deák, B. Kelbert, P. Bálint, Sz. Radócz, A. Kelemen, J. Sonkoly, T. Miglécz, G. Matus, A. Takács, V. A. Molnár, K. Süveges, L. Papp, L. Papp Jr., Z. Tóth, B. Baktay, G. Málnási Csizmadia, I. Oláh, E. Peti, J. Schellenberger, O. Szalkovszki, R. Kiss, and B. TÓthmérész
For understanding local and regional seed dispersal and plant establishment processes and for considering the ecotypes and other forms of specific variability, hard data of locally or regionally measured traits are necessary. We provided newly measured seed weight data of 193 taxa, out of which 24 taxa had not been represented in the SID, LEDA or BiolFlor databases. Our new measurements and formerly published data of locally collected seed weight records together covers over 70% of the Pannonian flora. However, there is still a considerable lack in seed weight data of taxonomically problematic genera, even though they are represented in the Pannonian flora with a relatively high number of species and/or subspecies (e.g. Sorbus, Rosa, Rubus, Crataegus and Hieracium). Our regional database contains very sporadic data on aquatic plants (including also numerous invasive species reported from Hungary and neighbouring countries) and some rare weeds distributed in the southwestern part of the country. These facts indicate the necessity of further seed collection and measurements.
Authors:Zs. Sári, T. Kovács, T. Csonka, M. Török, É. Sebő, J. Toth, D. Tóth, E. Mikó, B. Kiss, D. Szeőcs, K. Uray, Zs. Karányi, I. Kovács, G. Méhes, P. Árkosy, and P. Bai
Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.
Authors:R. Kiss, J. Sonkoly, P. Török, B. Tóthmérész, B. Deák, K. Tóth, K. Lukács, L. Godó, A. Kelemen, T. Miglécz, Sz. Radócz, E. Tóth, N. Balogh, and O. Valkó
Seeds ensure the survival and dispersal of the majority of vascular plant species. Seeds require species-specific germination conditions and display very different germination capacities using different germination methods. Despite the importance of plant generative reproduction, little is known about the germination capacity of the seeds of the Pannonian flora, particularly under field conditions. Our aim was to reduce this knowledge gap by providing original data on the germination capacity of 75 herbaceous species. We reported the germination capacity of 8 species for the first time. We also highlighted the year-to-year differences in the germination capacity of 11 species which could be highly variable between years. The data regarding the germination capacity of target species, as well as weeds and invasive species, can be informative for nature conservation and restoration projects. Our findings support the composition of proper seed mixtures for ecological restoration and also highlight the importance of testing seed germination capacity before sowing.