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The yield potential of wheat depends not only on genetic × environmental interactions, but also on various agronomic factors such as sowing date or the seed rate used for sowing. The main aim of this work was to determine possible correlations between the effects of different sowing dates and plant densities on the yield components of a collection of 48 wheat genotypes. Two-way analysis of variance on the data revealed that both sowing date and plant density, as main components, only had a minor effect on the yield component patterns. Correlation analysis, however, indicated that the sowing date had a greater effect on the yield components, while plant density was in closer correlation with the heading time (r = 0.90). The patterns determined for individual yield components at two different sowing dates and plant densities showed significant differences for spike length, spike fertility, grain number in the main spike, number of productive tillers, grain number on side tillers, mean grain number and grain weight. Genotypes that carry the winter (recessive) alleles of genes regulating vernalisation processes (VRN-A1, VRN-B1, VRN-D1) and the sensitive (recessive) alleles of the two genes responsible for photoperiod sensitivity (PPD-B1, PPD-D1) may have better tillering and consequently higher grain yield, though this may depend greatly on the year.

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Studies on plant development phases and yield component patterns of wheat are essential for a better understanding of adaptation in wheat. Our main aim was to carry out detailed phenological analyses of 18 wheat genotypes in three sowing times for determining the effect of sowing date on individual phenophases, and yield components. Sowing date had the single greatest effect on the start of intensive stem elongation. The longer vegetation period had a favourable effect on main spike length and on the spikelet number per spike, but had no influence on thousand-kernel weight and grain number per spike. The time between the first node appearance and start of intensive stem elongation had a significant effect on the number of reproductive tillers. A close association (R2 = 0.191) was observed during the second phase of intensive stem elongation between the boot stage-to-heading interval and the number of spikelets per spike. Two-way analysis of variance on the yield components showed that the sowing date, as a main factor, had a weaker effect on the phenophases than on morphological and developmental parameters. The insensitive allele of the Ppd-D1 gene shortened the time required for first node appearance and heading both in autumn and spring sowing.

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Authors: K. Szabó, G. Vasas, Á. Kiss and A. Naumov
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Authors: K. Mesterházy, V. Kiss, D. Gabler, A. Márton and L. Schilling
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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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A panel of orally administered lectins (100 mg/kg b.w.) of different binding specificities was tested for suppression of voluntary food consumption in prefasted rats. PHA isolectins (Phaseolus vulgaris) and RPA-I (Robinia pseudoacacia) were found to exert a marked and significant effect, but two other gut-binding lectins, i.e. SBA (Glycine max) and WGA (Triticum vulgare) and several non-binding lectins were ineffective. In cannulated rats PHA infused into the duodenum induced food suppression, i.e. binding of the lectin to the mouth or stomach was unnecessary. Suppression of food consumption lasted through the whole nocturnal feeding period, control (BSA) and experimental (PHA) curves of cumulative food consumption showed a V-like divergence. Suppression by PHA or RPA-I showed very similar time courses, but a long-lasting inhibition of gastric emptying was only observed in the RPA-treated animals. Intraperitoneally administered lectins suppressed food consumption much more effectively than the oral ones, whereas Galanthus nivalis agglutinin (GNA) had little or no effect. It is concluded that lectins can be used as effective tools for the modulation of food consumption and gastric emptying in experimental animals.

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Authors: Zs. Trábert, A. Engloner and A. Abonyi
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The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.

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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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