Zsuzsa Lisztes-Szabó

Bio: Zsuzsa Lisztes-Szabó is an academic researcher from Hungarian Academy of Sciences. The author has contributed to research in topics: Phytolith & Sorbus. The author has an hindex of 6, co-authored 24 publications receiving 124 citations. Previous affiliations of Zsuzsa Lisztes-Szabó include Hungarian National Museum & University of Debrecen.

Effects of selenate and red Se-nanoparticles on the photosynthetic apparatus of Nicotiana tabacum

Abstract: Selenium (Se) is a natural trace element, which shifts its action in a relatively narrow concentration range from nutritional role to toxicity. Although it has been well established that in plants chloroplasts are among the primary targets, the mechanism of toxicity on photosynthesis is not well understood. Here, we compared selenate and red-allotrope elemental selenium nanoparticles (red nanoSe) in in vitro tobacco cultures to investigate their effects on the structure and functions of the photosynthetic machinery. Selenate at 10 mg/L concentration retarded plant growth; it also led to a decreased chlorophyll content, accompanied with an increase in the carotenoid-to-chlorophyll ratio. Structural examinations of the photosynthetic machinery, using electron microscopy, small-angle neutron scattering and circular dichroism spectroscopy, revealed significant perturbation in the macro-organization of the pigment-protein complexes and sizeable shrinkage in the repeat distance of granum thylakoid membranes. As shown by chlorophyll a fluorescence transient measurements, these changes in the ultrastructure were associated with a significantly diminished photosystem II activity and a reduced performance of the photosynthetic electron transport, and an enhanced capability of non-photochemical quenching. These changes in the structure and function of the photosynthetic apparatus explain, at least in part, the retarded growth of plantlets in the presence of 10 mg/L selenate. In contrast, red nanoSe, even at 100 mg/L and selenate at 1 mg/L, exerted no negative effect on the growth of plantlets and affected only marginally the thylakoid membrane ultrastructure and the photosynthetic functions.

A morphometric study of variance in articulated dendritic phytolith wave lobes within selected species of Triticeae and Aveneae

Abstract: Morphometric analysis has proven to be an effective tool for distinguishing among phytolith assemblages produced by closely related plant taxa. Elongate dendritic epidermal phytoliths are produced in the inflorescence bracts of many cereal species. Under light microscopy, these articulated dendritic phytoliths produce wave patterns between the margins of the cells that are reported to have taxonomic significance. In this study we explore morphometric variance among the lobes of the wave patterns formed by the articulated dendritic phytoliths within selected species of cereals as a first step towards understanding the variance between species. We found that there is often significant variance in dendritic wave lobes among different accessions of a species, among the different types of inflorescence bracts of the species (glumes, lemmas and paleae), and among each bract type’s location on the inflorescence (upper, middle and lower third of inflorescence spike or panicle). We observed that shape morphometries are typically more reliable and require a smaller sample size for statistical confidence than size morphometries. We further observed that adequate samples sizes for analysis of several shape morphometries of articulated dendritic wave lobes are considerably smaller than those reported to be required for analysis of the same morphometries of individual or isolated dendritic phytoliths. To gain a preliminary sense whether there is potential for discriminating between taxa in light of the significant variance within species, we compared our data to archaeological material from the historical center of Brussels. We demonstrate that while there is considerable variance in the morphometries among accessions, bract types and inflorescence locations within each species, there may yet be potential for discriminating between cereal species in archaeological samples by the morphometries of their dendritic phytolith wave lobes. We present one possible paradigm for conducting such analysis on archaeological material.

Phytolith analysis of Poa pratensis (Poaceae) leaves

Abstract: Phytoliths in Poa pratensis L. (Poaceae) leaf blades and sheaths are described in this study. The role of plant opal particles-known as phytoliths-is considerable in taxonomical studies, and their long-term preservation in sediments makes them a useful tool in the reconstruction of ancient plant communities and plant-human interactions. All together, 2244 phytoliths were counted and analyzed in 25 plant samples (5 shoots of 5 specimens and approximately 500-600 phytoliths per specimen). The biogenic silica content of P. pratensis leaves was determined at 2.61%, and 27 morphotypes have been described using the International Code for Phytolith Nomenclature. Two morphotypes are described for the first time in this study. Long cells (elongate psilate and sinuate morphotypes) and short cells (rondel-trapeziform elongated and rounded morphotypes) are frequently present in this species. Differences in morphotype frequency and significant differences in a few simple morphometric data (length, width, height) of long cells and short cells were found among specimens, which suggests that these features vary depending on environmental factors and the maturity of leaf tissues.

Quantifiable differences between phytolith assemblages detected at species level: analysis of the leaves of nine Poa species (Poaceae)

Abstract: The taxonomic value of phytolith assemblages and their degree of variability within different species of the same genus is still an undervalued issue in the botanical range of phytolith studies. However the understanding of grass phytolith variance and its implications to plant systematics is doubtless. In the present study phytoliths of the lateral shoots (leaves) of nine, globally distributed Poa species (Pooideae – Poaceae) are described. Phytoliths were recovered from Poa specimens by the dry ashing technique. Altogether 6223 disarticulated phytoliths were counted (approximately 500–700 phytoliths per species) in 54 plant samples, which cover six shoots of nine species. Not only the relative frequency of each morphotype was calculated, but measurements were conducted to determine the biogenic silica content of Poa lateral shoots. A phytolith reference collection for the nine selected species of a worldwide importance was also compiled. The description of the most significant phytolith morphotypes and their taxonomic relationships are given here. Results suggest that the biogenic silica content of the Poa lateral shoots was determined to be relatively high within all nine species. Phytolith assemblage data was subjected to multivariate statistical analyses (e.g., CA and PCA) in order to find differences and similarities among the nine Poa species. Results show that the two closely related Poa of the P. pratensis species group, namely the P. pratensis and P. angustifolia , only slightly differ from the other Poa species if we consider their rondel-trapeziform short cells (SC) phytolith frequencies.

A Debreceni Egyetem Herbáriuma (DE) I.: A „Soó Rezső Herbárium”

Abstract: The paper introduces the herbarium of Debrecen University (DE). All specimens of theherbarium were documented by digital photographs, and all data from the labels were entered into anExcel spreadsheet. The largest collection of Herbarium DE, the “Soo Rezső Herbarium” (abbreviation:SRH) consists of ca. 38.000 specimens from almost all European countries, but mainly from Hungaryand the neighbouring countries. Most of the specimens originate from Hajdu-Bihar, Pest, Győr-MosonSopron, Borsod-Abauj-Zemplen, Veszprem and Szabolcs-Szatmar-Bereg counties. The SRH stores aconsiderable amount of original/authentic specimens collected by Hungarian botanists, primarily byRezső Soo and his followers, as well as Sandor Polgar. The most rapid growth of the SRH took place inthe first half of the last century (1930–1950). By contrast, the collection was practically not developedbetween 1955 and 2000. After the millennium it started to grow again. Data on the most substantialpart of the SRH covering native plants collected in the present-day Hungary are summarized inElectronic Appendix 1. (incl. taxon name, settlement, collecting date, collector, file name ofdocumentary photograph).

Climate History and the Modern World

Abstract: H. H. Lamb's latest book on the earth's changing climate is a carefully crafted work covering four areas: the physical basis of climate and climate change, the methods of climate reconstruction, the history of climate since the height of the last glaciation, and the impact of climate on human affairs. The book will be of particular interest to three groups. Atmospheric scientists interested in the long history of climate behavior (but perhaps overwhelmed by Lamb's all-encompassing work on the topic, Climate: Past, Present and Future, vol. II, Methuen, New York), will find Climate History and the Modern World to be a good titration of the fuller work. Scientists in other fields, including social scientists grappling with issues of climate-society interaction, will find the book a good entree into the field. Finally, Lamb himself suggests that the book will be useful to resource managers and other decision makers trying to avoid negative climate impacts. With this last audience in mind, no doubt, Lamb has chosen a style that eschews extensive footnoting and references (though sufficient citations are included to lead to further information). This works quite well and seems reasonable in view of his carefully documented previous writings.

Revealing a 5,000-y-old beer recipe in China

Abstract: The pottery vessels from the Mijiaya site reveal, to our knowledge, the first direct evidence of in situ beer making in China, based on the analyses of starch, phytolith, and chemical residues. Our data reveal a surprising beer recipe in which broomcorn millet (Panicum miliaceum), barley (Hordeum vulgare), Job’s tears (Coix lacryma-jobi), and tubers were fermented together. The results indicate that people in China established advanced beer-brewing technology by using specialized tools and creating favorable fermentation conditions around 5,000 y ago. Our findings imply that early beer making may have motivated the initial translocation of barley from the Western Eurasia into the Central Plain of China before the crop became a part of agricultural subsistence in the region 3,000 y later.

Impact of Selenium and Copper Nanoparticles on Yield, Antioxidant System, and Fruit Quality of Tomato Plants.

Abstract: The effects of nanoparticles (NPs) on plants are contrasting; these depend on the model plant, the synthesis of the nanoparticles (concentration, size, shape), and the forms of application (foliar, substrate, seeds). For this reason, the objective of this study was to report the impact of different concentrations of selenium (Se) and copper (Cu) NPs on yield, antioxidant capacity, and quality of tomato fruit. The different concentrations of Se and Cu NPs were applied to the substrate every 15 days (five applications). The yield was determined until day 102 after the transplant. Non-enzymatic and enzymatic antioxidant compounds were determined in the leaves and fruits as well as the fruit quality at harvest. The results indicate that tomato yield was increased by up to 21% with 10 mg L−1 of Se NPs. In leaves, Se and Cu NPs increased the content of chlorophyll, vitamin C, glutathione, 2,2′-azino-bis(3-ethylbenzthiazolin-6-sulfonic acid (ABTS), superoxide dismutase (SOD), glutathione peroxidase (GPX) and phenylalanine ammonia liasa (PAL). In fruits, they increased vitamin C, glutathione, flavonoids, firmness, total soluble solids, and titratable acidity. The combination of Se and Cu NPs at optimal concentrations could be a good alternative to improve tomato yield and quality, but more studies are needed to elucidate their effects more clearly.

Bacterial Seed Endophytes of Domesticated Cucurbits Antagonize Fungal and Oomycete Pathogens Including Powdery Mildew.

Abstract: The cucurbit vegetables, including cucumbers, melons and pumpkins, have been cultivated for thousands of years without fungicides. However, their seed germination stage is prone to be infected by soil-borne fungal and oomycete pathogens. Endophytes are symbionts that reside inside plant tissues including seeds. Seed endophytes are founders of the juvenile plant microbiome and can promote host defense at seed germination and later stages. We previously isolated 169 bacterial endophytes associated with seeds of diverse cultivated cucurbits. We hypothesized that these endophytes can antagonize major fungal and oomycete pathogens. Here we tested the endophytes for in vitro antagonism (dual culture assays) against important soil-borne pathogens (Rhizoctonia solani, Fusarium graminearum, Phytophthora capsici, Pythium aphanideratum). The endophytes were also assayed in planta (leaf disk and detached leaf bioassays) for antagonism against a foliar pathogen of global importance, Podosphaera fuliginea, the causative agent of cucurbit powdery mildew. The endophytes were further tested in vitro for secretion of volatile organic compounds (VOCs) known to induce plant defense. Extracellular ribonuclease activity was also tested, as a subset of pathogenesis-related (PR) proteins of plant hosts implicated in suppression of fungal pathogens, displays ribonuclease activity. An unexpected majority of the endophytes (70%, 118/169) exhibited antagonism to the five phytopathogens, of which 68% (50/73) of in vitro antagonists belong to the genera Bacillus and Paenibacillus. All Lactococcus and Pantoea endophytes exhibited anti-oomycete activity. However, amongst the most effective inoculants against Podosphaera fuliginea were Pediococcus and Pantoea endophytes. Interestingly, 67% (113/169) of endophytes emitted host defense inducing VOCs (acetoin/diacetyl) and 62% (104/169) secreted extracellular ribonucleases in vitro, respectively. These results show that seeds of cultivated cucurbits package microbes with significant disease-suppression potential. As seeds can act as vectors for genetic transmission of endophytes across host generations, it is interesting to hypothesize whether humans, when selecting seeds of healthy hosts, may have inadvertently selected for disease-suppressing seed endophytes. As the majority of pathogen-suppressing endophytes belong to Bacillus and Paenibacillus, and since Bacilli are widely used as commercial biocontrol agents of vegetables, we propose that these agents are mimicking the ecological niche established by their endophytic cousins.