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  • Author or Editor: J. Farkas x
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In this study pedotransfer functions (PTFs) were developed to estimate the soil water retention curves (SWRCs) for Rye Island (Csallóköz, S. W. Slovakia). A representative set of soil water retention curves was measured using a laboratory method on samples taken from soils the study area. Particle size distribution and bulk density were determined as well. Multiple regression analysis was used for estimating nine statistical relationships in order to predict the drying part of the SWRCs. Texture and bulk density were used as predictors. Pedotransfer functions were verified on another set of measured water retention curves from the same territory as well as on SWRCs determined for soils of the Szigetköz region in Hungary. A good agreement was found between the calculated and measured SWRCs for the Slovakian soils, while somewhat poorer estimates could be given for Hungarian soils.

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The responses of the snail central neurons (Helix pomatia, Lymnaea stagnalis) and the isolated Helix heart were characterized evoked by cyanobacterial extracts (Cylindrospermopsis raciborskii ACT strains) isolated from Lake Balaton (Hungary). The nicotinergic acetylcholine (ACh) receptors in the CNS (both excitatory and inhibitory) were blocked by the extracts of ACT 9502 and ACT 9505 strains and the anatoxin- a (homoanatoxin-a) producing reference strain of Oscillatoria sp. (PCC 6506), similar to the inhibitory effects of the pure anatoxin-a. The enhancement of the ACh responses by the ACT 9504 extract suggests additional, probably acetylcholine esterase inhibitory mechanisms. On the isolated Helix heart the crude ACT 9505 and PCC 6506 extracts evoked frequency increase and transient twitch contraction, opposite to the ACh evoked heart relaxation. Anatoxin-a similarly contracted the heart but did not increase its contration frequency. These data suggest the involvement of some non-cholinergic mechanisms, acting very likely by direct modulation of the electrical or contractile system of the isolated heart. Diversity of the effects evoked by the cyanobacterial extracts in the CNS and heart suggest pharmacologically different neuroactive components among the secondary metabolites of the cyanobacteria acting on both (anatoxin-a like) cholinergic and (unidentified) non-cholinergic receptors.

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Authors: Ágnes Vehovszky, Henriette Szabó, A. Ács, J. Győri and Anna Farkas

(Artemia) nauplii was used to asses the toxicity of rotenone, MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), MP+ (1-methyl-4-phenylpyridinium) and the effect of L-DOPA co-treatment with rotenone. Rotenone had a dose dependent effect on mortality (LC50: 0.37 ± 0.04 μM mean ± S E, n = 24), while MPTP and MP+ proved to be toxic in millimolar range (LC50: 0.21 ± 0.09 mM and 0.20 ± 0.08 mM, respectively, n = 4). L-DOPA (50–200 μM) co-treatment increased the survival of the rotenone-treated animals (LC50: 0.51 ± 0.23 μM, 1.03 ± 0.66 μM, and 0.76 ± 0.52 μM, respectively). In the whole body tissue homogenates of Artemia, sublethal (up to 0.3 μM) concentrations of rotenone increased the glutathione S-transferase (GST) activity by up to 50 about percent (LC50: 53.3 ± 6.8 nM/min/mg protein, against 34.7 ± 3.6 nM/min/mg protein, n = 4). Nauplii treated in 100 mM L-DOPA and rotenone together showed further increase of GST activity all across the range of rotenone concentrations. These results on Artemia nauplii show similarities with other animal models, when complex I inhibitors were tested. Biochemical measurements suggest a protective role of L-DOPA by increasing the GST activity as part of the intracellular defences during toxin-evoked oxidative stress.

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Authors: C. Farkas, A. Hagyó, E. Tóth, J. Szabó and T. Németh

This study was carried out to evaluate the soil hydrophysical properties and soil water regime of two irrigated maize fields in order to support irrigation planning and management. The experimental sites were located in Mezohegyes (MZH) and Hódmezovásárhely (HMV) in SE Hungary. In total 11 monitoring stations were chosen, using information from a previously developed, GIS-based agro-geoinformation system. In 2003 and 2004 soil sampling and in situ measurements were performed to determine the soil hydrophysical properties and soil water content dynamics. The hydraulic conductivity of the topsoil was evaluated from double ring infiltrometer measurements. A previously calibrated TDR 300 instrument and a 3T-M capacitance probe were used for quantifying the soil water content. Both types of equipment were found to require calibration and testing under field conditions before use. It was concluded that the study fields could be considered relatively homogeneous in relation to both soil hydrophysical properties and soil water regime. Thus, monitoring stations established for one or two carefully selected soil profiles could provide enough data to ensure proper decisions on irrigation. The results indicate that the soil management system and irrigation strategy used in the experimental fields ensured satisfactory soil and soil moisture conditions.

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In the present work, bio and conventional forms of spice red pepper were analysed using various high performance liquid chromatographic (HPLC) systems for their carotenoid, tocopherol and vitamin C contents. The carotenoid pigment was fractionated into free xanthophylls, monoesters, carotenes and diesters with newly developed reversed phase HPLC, while a -, b - and g -isomers of vitamin E were separated by normal phase chromatography. Ion-pair chromatography on a C-18 column provided good separation and quantification of vitamin C. The peppers included new resistant varieties and hybrids that are essential for bio-production. It was found that crossing new disease-resistant varieties such as Kaldom and Kalorez with susceptible ones such as Rubin and SZ-20 produced resistant hybrids that contained higher levels of quality components compared to the parents, particularly when grown and cultivated under organic farming conditions.

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Authors: Z. Farkas, J. Márki-Zay, Judit Kucsera, Cs. Vágvölgyi, W. Golubev and Ilona Pfeiffer

Wickerhamomyces anomalus VKM Y-159 strain produces two types of toxin designated as WAKT a and WAKT b, encoded by chromosomal genes. The WAKT a toxin is heat-labile, pronase sensitive acting in pH range 3–4 affecting on several yeasts including pathogenic Candida species while the WAKT b toxin is protease- and thermo-resistant, acting in pH range 3–7 on two species, Candida alai and Candida norvegica. The rapid decrease of the number of viable cells after toxin treatment demonstrates that both toxins have cytocidic effect.

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From the combined phylogenetic analysis of multi-locus sequence data of the Lecanoraceae including two nuclear protein-coding markers (RPB2 and RPB1), the internal transcribed spacer and a fragment of the mitochondrial small subunit, found that the originally monotypic eastern Asian genus Verseghya is positioned within the Verseghya-Lecidella-Pyrrhospora clade of the Lecanoraceae and includes one more taxon Verseghya thysanophora widely distributed in Northern Hemisphere.

The genus Lecidella forming the Lecidella-Glaucomaria subclade within the same Verseghya-Lecidella-Pyrrhospora clade of the Lecanoraceae found to have tendency to be polyphyletic after including the recently described eastern Asian taxon Lecidella mandshurica into phylogenetic analysis of the Lecanoraceae. It is shown that Lecidella mandshurica was previously recorded from China sub Lecidella aff. elaeochroma.

The originally monotypic eastern Asian genus Sedelnikovaea forming a monophyletic branch within the Sedelnikovaea-Lecanoropsis subclade and being in out-position to the Rhizoplaca-Protoparmeliopsis s. str. clade of the Lecanoraceae found to include three more taxa, i.e. Sedelnikovaea marginalis, S. pseudogyrophorica, and S. subdiscrepans.

The Eurasian Protoparmeliopsis bolcana, and the eastern Asian P. kopachevskae, are illustrated for the first time as being positioned within the Protopameliopsis branch of the Lecanoraceae, while the South Korean ‘Protoparmeliopsis’ chejuensis found to be positioned in separate monophyletic branch from all other branches of the Rhizoplaca-Protoparmeliopsis s. l. clade of the Lecanoraceae.

The genus Polyozosia A. Massal. as earlier name for the former Myriolecis branch of the Lecanoraceae is accepted as far the type species of the latter genus, i.e. P. poliophaea, found to be positioned within this branch. The Polyozosia robust monophyletic branch is positioned in the outermost position in the Rhizoplaca-Protoparmeliopsis s. str. clade of the Lecanoraceae.

Position and species content of the accepted genera Glaucomaria, Lecanoropsis, Omphalodina, Polyozosia, and Straminella are discussed in separate nrITS and mtSSU, and combined phylogeny based on concatenated sequences of nrITS, mtSSU, RPB2 and RPB1 genes.

Fourty new combinations are proposed: Glaucomaria bicincta, G. carpinea, G. leptyrodes, G. lojkaeana, G. subcarpinea, G. sulphurea, G. swartzii, G. swartzii subsp. caulescens, G. swartzii subsp. nylanderi, Lecanoropsis anopta, L. macleanii, Omphalodina chrysoleuca, O. huashanensis, O. opiniconensis, O. phaedrophthalma, O. pseudistera, Palicella anakeestiicola, Polyozosia albescens, P. andrewii, P. contractula, P. crenulata, P. dispersa, P. hagenii, P. perpruinosa, P. populicola, P. pruinosa, P. reuteri, P. sambuci, P. semipallida, P. straminea, P. thuleana, Sedelnikovaea marginalis, S. pseudogyrophorica, S. subdiscrepans, Straminella bullata, S. burgaziae, S. conizaeoides, S. densa, S. maheui, S. varia, and Verseghya thysanophora. Validation of one name as Polyozosia perpruinosa Fröberg ex S. Y. Kondr. L. Lőkös et Farkas is also proposed.

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Authors: S. Kondratyuk, L. Lőkös, S. Tschabanenko, M. Haji Moniri, E. Farkas, X. Wang, S.-O. Oh and J.-S. Hur

Seventeen taxa new for science, i.e. Absconditella baegasanensis, Caloplaca hallasanensis, C. subconcilians, Fellhanera chejuensis, F. maritima, Lecania coreana, L. rinodinoides, Lichenostigma heterodermiae, Micarea coreana, Phoma heterodermiae, Protoparmeliopsis chejuensis, Roselliniopsis phaeophysciae, Topelia jasonhurii (all from South Korea); Caloplaca dzhankoiensis (from Ukraine); Protoparmeliopsis pseudogyrophoricum (from China); P. taranii (from Russia); and Seirophora blumii (from several Central Asian countries) are described, compared with closely related taxa, and illustrated.Five new combinations are proposed: Caloplaca subscopularis, Protoparmeliopsis crustaceum, P. gyrophoricum, P. mazatzalensis, and P. pinguis.A total of 64 lichen-forming and lichenicolous fungi are reported here as new for South Korea (i.e. Abrothallus microspermus, Amandinea melaxanthella, Arthonia epiphyscia, Arthothelium ruanum, Aspicilia contorta subsp. hoffmanniana, Biatora globulosa, Brigantiaea purpurata, Caloplaca gordejevii, C. micromera, C. oxneri, C. subscopularis, C. trassii, Candelariella reflexa, Dirina massiliensis, Endococcus cf. verrucosus, Hyperphyscia adglutinata, Hypogymnia austerodes, H. occidentalis, Ionaspis lacustris, Lecanora barkmaniana, Lecanora cf. marginata, L. symmicta, L. varia, Lichenochora obscuroides, Lichenodiplis lecanorae, Lopadium coralloideum, Melaspilea bagliettoana, Menegazzia subsimilis, Micarea denigrata, M. peliocarpa, Myriospora heppii, Myriotrema masonhalei, Ochrolechia frigida, Opegrapha calcarea, O. phaeophysciae, Parmelia subdivaricata, Pertusaria aff. alpinoides, P. commutans, P. ophthalmiza, P. sphaerophora, P. subcomposita, Phlyctis aff. argena, Physconia hokkaidensis, Porina farinosa, Punctelia subrudecta, Pyrenula balia, P. castanea, P. laevigata, P. neojaponica, Rhizocarpon badioatrum, Rinodina fimbriata, R. oleae, R. polyspora, R. pyrina, R. sophodes, R. teichophila, Scoliciosporum chlorococcum, Sphinctrina tubaeformis, Stigmidium fuscatae, Taeniolella phaeophysciae, Thelotrema nipponicum, Toninia aromatica, Topeliopsis aff. azorica, and Trypethelium indutum); and two new for China (i.e. Caloplaca bassiae, Lecania rabenhorstii). Detailed locality data and annotations are given for further 22 noteworthy species, which are rare in South Korea (i.e. Agonimia opuntiella, Agonimiella pacifica, Amandinea punctata, Biatora longispora, Brigantiaea ferruginea, Caloplaca squamosa, Chrysothrix candelaris, Coenogonium luteum, Diploschistes actinostomus, Hyperphyscia crocata, Leucodecton desquamescens, Menegazzia nipponica, Pertusaria commutata, P. multipuncta, P. quartans, P. submultipuncta, P. aff. subobductans, P. velata, Phaeophyscia orbicularis, Porina leptalea, Pyrenula pseudobufonia, and Trapelia coarctata); and for two species rare in China (i.e. Buellia badia, Letrouitia transgressa).

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Authors: S. Y. Kondratyuk, L. Lőkös, E. Farkas, S.-O. Oh and J.-S. Hur

One new genus, i.e. Ivanpisutia S. Y. Kondr., L. Lőkös et J.-S. Hur, similar to the genera Carbonea and Lecidella of the Lecanoraceae, and eleven new species of lichen-forming and lichenicolous fungi, i.e. Agonimia cavernicola S. Y. Kondr., L. Lőkös et J.-S. Hur, Caloplaca chujaensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Lichenochora makareviczae S. Y. Kondr., L. Lőkös et J.-S. Hur, and Rusavskia coreana S. Y. Kondr. et J.-S. Hur from South Korea; Caloplaca neobaltistanica S. Y. Kondr. et J.-S. Hur from China; and Caloplaca mandshuriaensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Ivanpisutia oxneri S. Y. Kondr., L. Lőkös et J.-S. Hur, Lecanora lojkahugoi S. Y. Kondr., L. Lőkös et J.-S. Hur, Lecidella mandshurica S. Y. Kondr., L. Lőkös et J.-S. Hur, Opegrapha verseghyklarae S. Y. Kondr., L. Lőkös et J.-S. Hur and Rusavskia ussurica S. Y. Kondr. et J.-S. Hur from the Russian Far East, are described and illustrated, compared with closely related taxa.

Fourteen species of lichen-forming and lichenicolous fungi are reported as new for South Korea (i.e. Arthonia molendoi, Caloplaca arenaria, C. sideritis, Candelariella coralliza, Lecanactis cf. dilleniana, Micarea misella, Porina aff. ahlesiana, P. distans, Protoparmeliopsis pseudogyrophorica, Pyxine subcinerea, Stigmidium rivulorum, Stigmidium squamariae, Vouauxiomyces ramalinae, Zwackhiomyces lithoideae); 8 for Russia or the Russian Far East (i.e. Absconditella baegasanensis, Bactrospora cf. corticola, Biatoridium aff. monasteriense, Collemopsidium cf. halodytes, Lecanora cf. hafelliana, Opegrapha phaeophysciae, Phacopsis oxyspora, Polycoccum clauzadei, Vouauxiomyces ramalinae; and 2 species new to China (Caloplaca zoroasteriorum, Seirophora blumii).

Detailed locality data and annotations are given for further 27 noteworthy species, which are rare in South Korea (i.e. Arthonia epiphyscia, Buellia griseovirens, Caloplaca austrocoreana, C. chejuensis, C. micromera, C. multicolor, C. subconcilians, C. trassii, Catillaria atomaroides, Enterographa leucolyta, Fellhanera chejuensis, Fellhanera subtilis, Fuscidea austera, Fuscopannaria incisa, Ionaspis lacustris, Lecania rinodinoides, Lobaria japonica, Lobaria spathulata, Micarea coreana, Phaeophyscia endococcinodes, Physcia stellaris, Pyxine limbulata, Scoliciosporum chlorococcum, S. umbrinum, Sculptolumina japonica, Trapelia coarctata, T. placodioides); and for 3 species rare in Russia (i.e. Dactylospora lobariella, Megalospora tuberculosa, Nipponoparmelia perplicata); and Dimelaena aff. oreina in China.

Arthonia epiphyscia is for the first time recorded from Anaptychia isidiata, and Arthonia molendoi is for the first time recorded from Caloplaca subscopularis.

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Authors: S. Y. Kondratyuk, L. Lőkös, E. Farkas, S.-O. Oh and J.-S. Hur

Eleven new for science species of lichen-forming fungi, i.e.: Amandinea pseudomultispora, Buellia chujadoensis, Fuscidea coreana, F. extremorientalis, Hafellia extremorientalis, H. pseudosubnexa, Halecania subalpivaga, Lecanactis subdilleniana, Lecania chirisanensis, Maronella coreana, and Melanophloea coreana are described, illustrated and compared with closely related taxa. Amandinea polyspora, Catillaria nigroclavata, Ivanpisutia oxneri, Lecanora saligna, L. sambuci, and Lecidella mandshurica are proved to be new to Korea.

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