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In our investigations the membrane filtration of quality wines (Tokaji Hárslevelű and Egri Bikavér) — based on diafiltration principles, applying nanofiltration membranes — has been studied. For the diafiltration experiments a relatively dense nanofiltration membrane NF 45 has been used, while for simple wine concentrations a membrane developed for organic components rejection NF200 has been investigated. The mixture of the retarded wine compounds was considered the main product of the process. The permeate that crossed the membrane was handled as the by product. Separated wine samples and the original wines have been subjected to gas chromatographic analysis: according to the results the partition of the main components and aroma compounds of the samples was approximately equal between the main and by-product. Membrane separation has been applied in accordance with a “prelaborated” experimental plan, when completing it the effect of operational parameters on the effectiveness of the process has been evaluated and analysed. By mathematical modelling of the phenomenon empirical and quasiempirical relations were set up, and solutions for the practical realization of the procedure were searched for. Our new model describes the filtration efficiency with our new index in the function of the operational parameters’ influence. The significance of the relation is, that the knowledge of the wine-constants might promote the expedient choice of the membrane, which is a primary aspect in planning and creating the process optimal.

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It has been proved that because of the different past of the parcels regarding their soil, agronomical and technological parameters, weed sampling results may not be generalised. Therefore it is necessary to study those solutions how to determine on an acceptable confidence level a parcel’s weed infestation with optimised sampling techniques.For studying the question we have delimited on wheat stubble a total sample area of 36×54 metres (using it as reference) and divided it into 2×2 cells giving a total of 486 sample cells. Then we surveyed the weed infestation and GPS recorded the location of each cell.We have analysed the weed infestation data with mathematical and statistical methods comparing the results of cells with each other and with the total sample area. We found that in several cases of different sample cells weed infestation displayed a diverse picture. This way sampling of weeds is extremely difficult.We found close relation between relative frequency of weeds and sampling accuracy. Therefore sampling is reliable only for surveying the frequent weeds in a parcel, while more rarely found weeds (e.g. spots of perennials) are to be scouted only by means of going over the parcel and GPS recording them. Otherwise, in the case of a traditional sampling process, the number of sampling cells required for acceptable reliability is unnecessarily high.Consequently, it is necessary to further study the economic and cost efficiency aspects of the needed weed sample density from the point of view of reasonable sample density, accuracy and optimal yield.

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Acta Biologica Hungarica
Authors:
Anna Blázovics
,
Éva Sárdi
,
Klára Szentmihályi
,
L. Váli
,
Mária Takács-Hájos
, and
Éva Stefanovits-Bányai

Redox homeostasis can be considered as the cumulative action of all free radical reactions and antioxidant defences in different tissues, which provide suitable conditions for life. Transition metal ions are ubiquitous in biological systems. Beta vulgaris var. rubra (table beet root) contains several bioactive agents (e.g. betain, betanin, vulgaxanthine, polyphenols, folic acid) and different metal elements (e.g. Al, B, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Zn), which act on the various physiological routes. Therefore we studied the effect of this metal rich vegetable on element content of the liver in healthy rats. Male Wistar rats (n = 7) (200 ± 20 g) were treated with lyophilised powder of table beet root (2 g/kg b. w.) added into the rat chow for 10 days. Five healthy animals served as control. We found significant accumulation of Cu, Fe, Mg, Mn, Zn and P in the liver, which was proved by ICP-AES measurements. We suppose that the extreme consumption of table beet root can cause several disturbances not only in cases of healthy patients but, e.g. in patients suffering with metal accumulating diseases, e.g. porphyria cutanea tarda, haemochromatosis or Wilson disease-although moderate consumption may be beneficial in iron-deficiency anaemia and inflammatory bowel diseases.

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Acta Alimentaria
Authors:
Kerti K. Badakné
,
L. Szalóki-Dorkó
,
Zs. Zalán
,
N. Adányi
, and
K. Takács
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Tomato spotted wild virus (TSWV) has become an important plant pathogen during the past 10 years in Hungary. This virus belongs to the family of Bunyaviridae, genus Tospovirus. According to the latest studies, this virus has about 1090 host plant species, including crops and weeds. In the autumn of 2009, some Aristolochia clematitis plants were collected showing symptoms of TSWV infection. On the basis of electron microscopic and molecular studies, leaf samples of Aristolochia clematitis L. found in a vineyard proved to be infected with Tomato spotted wilt virus (TSWV). This is the first report on the occurrence of TSWV in Aristolochia in Hungary.

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The nucleotide sequence of the coat protein (CP) gene and the 3' non-translated region, in relation to aphid transmission of 7 potato tuber necrotic ringspot isolates of Potato virus Y (PVYNTN) were studied. Five isolates originated from different areas of potato fields in Hungary and two German isolates served as controls. A 5' tail of the nucleotide sequences of the CP region and 3' non-translated region (NTR) were determined. Sequence data were sent to the EMBL GeneBank Database. Homology of nucleotide and amino acid sequences were high among the studied PVY isolates. According to the characteristic regions, all isolates belonged to the PVYNTN strain. All of the tested isolates could be transmitted by the aphid Myzus persicae Sulzer to the test plant Nicotiana tabacum L. verifying the wide distribution of tuber necrotic ringspot strain in Hungary. Our data suggest that the high homology found in the CP region of the different isolates, are suitable for development of coat protein mediated resistance against PVY in commercially important host plants like, e.g. potato.

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Cereal Research Communications
Authors:
K. Végh
,
E. Osztoics
,
P. Csathó
,
J. Csillag
,
L. Radimszky
,
G. Baczó
,
M. Magyar
,
T. Takács
,
A. Lukács
, and
M. Karátsonyi
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Acta Botanica Hungarica
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.

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Agrokémia és Talajtan
Authors:
Péter Csathó
,
E. Osztoics
,
J. Csillag
,
T. Lengyel
,
L. Gonda
,
L. Radimszky
,
G. Baczó
,
M. Magyar
,
K. R. Végh
,
M. Karátsonyi
,
T. Takács
,
A. Lukács
, and
T. Németh

Depending on their origin, sedimentary phosphate rocks (PRs) may differ in their P solubility, and, as a consequence, in their agronomic effectiveness. The effect of six phosphate rocks (PR) - originating from Algeria (ALG), North Florida (FLO), North Carolina (NCA), Senegal (SEN) Morocco (MOR) and Hyperphosphate (HYP) with various P solubility (evaluated by 2% formic acid, 2% citric acid, and neutral ammonium citrate) - as well as single superphosphate (SSP) and superphosphate + lime (SSP + Ca) (each P source on 4 P levels, with doses of 0, 100, 400 and 1600 mg P 2 O 5 ·kg -1 soil) on the shoot yield of tillering stage spring barley, soil available P (i.e. H 2 O, Olsen, Bray1, Lakanen-Erviö (LE) and ammonium lactate (AL) extractable P contents) were studied in pot experiments set up with acidic sandy soil (Nyírlugos, Hungary) and acidic clay loam soil (Ragály, Hungary), both with low P supplies.  The average spring barley shoot yield at the beginning of shooting was 95% higher on the colloid-rich acidic (pH KCl : 4.5) clay loam soil than on the colloid-poor acidic (pH KCl : 3.8) sandy soil. The differences in the solubility of phosphate rocks showed close correlation to the differences in P responses. On both soils, the correlation between total PR-P added and P responses in spring barley shoot yield was much weaker than that between neutral ammonium citrate soluble PR-P added and P responses in spring barley shoot yield. When phosphate rocks were applied as P sources, the comparison of soil test P methods showed a different picture on the two soils. In the case of the acidic sandy soil (Nyírlugos), the strongly acid LE-P (r² = 0.83) and AL-P (r² =0.74) tests gave the highest correlation coefficients with spring barley responses to P, while on the acidic clay loam soil (Ragály) these were achieved by the Olsen-P (r² = 0.88) and Bray1-P (r² =0.88) methods. 

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Acta Botanica Hungarica
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.

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