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The transitions between various developmental phases are critical in determining the ecological adaptation and yield of cereals. In order to elaborate a methodology for establishing the timing of the consecutive plant developmental phases from germination to the fully developed plant, regular measurements of changes in developmental components were carried out on one winter (Kompolti Korai) and one spring (Morex) barley cultivar in a model experiment. Under the controlled environmental conditions linear regression was characteristic of the associations between the chronological time and all or most of the time course data of plant height, tiller and leaf numbers. The initial growth of the spring barley was twice as intensive as that of the winter barley. The length of the stem elongation phases was similar for the two varieties, but the winter barley cultivar showed significantly more intensive stem growth compared to the spring barley. The spring barley reached all the plant developmental phases significantly earlier than the winter barley. For both cultivars, tillering continued till after first node appearance and there was a definite delay between first node appearance and the beginning of the stem elongation phase. The determination of the full series of phenophases, together with the evaluation of various yield components on the same plant, provide an excellent way of establishing plant developmental patterns and may make a significant contribution to achieving a better understanding of the associations between plant developmental patterns and the adaptation and yielding ability of cereals.

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Bending, twitching and quivering are different types of tentacle movements observed during olfactory orientation of the snail. Three recently discovered special muscles, spanning along the length of superior tentacles from the tip to the base, seem to be responsible for the execution of these movements. In this study we have investigated the ultrastructure, contractile properties and protein composition of these muscles. Our ultrastructural studies show that smooth muscle fibers are loosely embedded in a collagen matrix and they are coupled with long sarcolemma protrusions. The muscle fibers apparently lack organized SR and transverse tubular system. Instead subsarcolemmal vesicles and mitochondria have been shown to be possible Ca2+ pools for contraction. It was shown that external Ca2+ is required for contraction elicited by high (40 mM) K+ or 10−4 M ACh. Caffeine (5 mM) induced contraction in Ca2+-free solution suggesting the presence of a substantial intracellular Ca2+ pool. High-resolution electrophoretic analysis of columellar and tentacular muscles did not reveal differences in major contractile proteins, such as actin, myosin and paramyosin. Differences were observed however in several bands representing presumably regulatory enzymes. It is concluded that, the ultrastructural, biochemical and contractile properties of the string muscles support their special physiological function.

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Consumption of dietary supplements (DS) has been showing a persistent, rapidly growing tendency all over the world. A new branch has been created on the borderline of food and pharmaceutical industries. It is a general tendency that the policy and regulation towards the products of this branch are lagging far behind the practice. This is an especially important problem with adolescents. To work out an efficient regulatory framework, we have to have an adequate picture on consumer behaviour and attitudes towards these products. Based on literature analysis of two focus group interviews, we have developed a motivational model on usage of DS, which has been tasted during a direct-question survey involving more than 500 respondents. Our results have proven that the consumption of DS is proliferated among young recreational athletes. One quarter of them consumes proteins, one tenth L-carnitine at least 2–3 times a week. The most important motivational factor is the improvement of sport performance. The level of confidence in these products is considerably influenced by peers and trainers. The propensity to underestimate the potentially adverse consequences of these products is high.

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Barley-infecting isolates of Wheat dwarf virus (WDV) were collected in the field in the vicinity of the cities Dunakiliti, Heves and Siófok, in Hungary. Viral genomic DNA was amplified by the rolling circle amplification technique, digested with Hind III, cloned into pBSK+ plasmid and sequenced. The clones were of the same size and showed above 99% identity to each other. Based on DNA sequences WDV-D01, WDV-H1 and WDV-H07 isolates showed high identity (94–99%) to isolates of WDV barley strain and Barley dwarf virus and lower identity to Oat dwarf virus (71% identity) and WDV wheat strains (85% identity).

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Short-term effects of orally administered plant lectins, with special reference to the Phaseolus vulgaris agglutinin (phytohaemagglutinin, PHA), were studied in growing rats.  The orally administered PHA elicited a dose-dependent accumulation of liquor with elevated pH in the proximal small intestine. Although the concentration of a-amylase activity did not change, total a-amylase activity slightly, but significantly increased in the gut. When a panel of plant lectins with different carbohydrate binding specificities was tested at the dose of 100 mg/kg body weight, most of them stimulated the secretion of liquor, but the total a-amylase activity was increased only by PHA, ConA or WGA.

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Acta Botanica Hungarica
Authors:
K. Kiss
,
M. Duleba
,
Zs. Szilágyi
, and
A. Földi
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Acta Botanica Hungarica
Authors:
K. Szabó
,
G. Vasas
,
Á. Kiss
, and
A. Naumov
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In the present paper two species of leafhoppers (Cicadomorpha, Cicadellidae) are reported for the first time from Hungary. Both species were collected from ornamental plants along highway margins in the vicinity of Budapest. Liguropia juniperi (Lethierry, 1876) has already been reported from several European countries. Opsius smaragdinus Emeljanov, 1964 has only been previously reported from Ukraine and Asian part of Turkey.

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Purpose

This study aimed to examine the effectiveness of CO2 laser-assisted sclerectomy surgery (CLASS) in eyes with primary open-angle glaucoma (POAG) showing progression in spite of maximal local antiglaucomatous therapy.

Materials and methods

Patients with progressive POAG received CLASS treatment. We performed CLASS on 15 eyes (eight males and seven females). The primary endpoint was the change in the intraocular pressure (IOP), and additionally best spectacle-corrected visual acuity (BSCVA), C/D ratio (cup-to-disc), as well as use of antiglaucomatous drops were also investigated. Following the preoperative assessment, measurements were performed at 6-month follow-up.

Results

The average preoperative IOP was 26.13 ± 6.79 mmHg that dropped to 9.57 ± 4.09 mmHg at 1 day. IOP was stable at 1 month, 3 months, and 6 months. The BSCVA decreased to the 1-day and 1-week follow-up but returned to its original value to the 1-month check-up. Preoperatively, all patients were on maximal antiglaucoma drop therapy, after CLASS none of the patients needed antiglaucomatous treatment at 1 month. However, at 3 months, one of them needed antiglaucoma drops. C/D ratio showed non-significant changes.

Conclusions

CLASS procedure was found to be effective in decreasing IOP in POAG patients whose IOP was not compensated with maximal antiglaucomatous local therapy; patients needed significantly less local therapy following the CO2 laser surgery.

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