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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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Stress tolerance is associated with the activation of antioxidant compounds and enzyme systems that are capable of neutralising the reactive oxygen species (ROS) continually produced in response to stress. The present experiment was designed to compare the heat tolerance of four winter wheat varieties in the shooting and grain-filling stages by investigating changes detected in antioxidant enzyme activity and yield components in response to heat stress.Heat treatment was found to cause a significant rise in the activity of the glutathione-S-transferase and catalase enzymes, while there was usually a less intense decline in the activity of guaiacol peroxidase.An analysis of yield data revealed that heat stress had a more pronounced effect during grain filling in this experiment than at the beginning of shooting, as shown by the greater reduction in thousand-kernel weight and yield.

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Nine genotypes of melon (Cucumis melo L.) were selected for the investigation of regeneration. Most of the tested varieties showed regeneration ability on medium containing 0.5 mg l−1 or 1 mg l−1 BA, but following the appearance of shoot buds, only six varieties produced leafy shoots. The effect of combinations of BA with different auxins (IAA, NA, 2,4-D) and ABA in the culture medium on shoot regeneration was tested on cotyledon explants of ‘Hógolyó’ and ‘Hale’s Best’. To establish optimal conditions for the adventitious shoot induction six types of seedling-derived explants were prepared from seedlings of four different ages. The best results for shoot forming capacity were achieved with cotyledons followed by decapitated seedlings and hypocotyls derived from 4-day-old seedlings. Cotyledon segments of ‘Hógolyó’ and ‘Hale’s Best’ were also cultivated on media with different concentrations of IAA and BA supplemented with 0.26 mg l−1 ABA. The highest number of well-formed plantlets was counted for ‘Hógolyó’ on the medium supplemented with 0.9 mg l−1 BA+ 0.6 mg l−1 IAA+ 0.26 mg l−1 ABA. This is the first report on the in vitro regeneration of ‘Hógolyó’ from decapitated seedling and hypocotyl explants and of ‘JavÍtott Zentai’, ‘Muskotály’, ‘Hógolyó’, ‘Tétényi csereshéjú’ and ‘Magyar Kincs’ from cotyledon explants.

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Western corn rootworm (WCR) first appeared in Europe near Belgrade airport in 1992. The first adult of this species was found near Mórahalom, in the southern part of Hungary, on 30th June 1995. Small-plot trials were started in Szeged (Cereal Research Non-Profit Co.) and large-scale trials in Mezohegyes (Ménesbirtok Ltd.) in 1996 to elaborate strategies to control this insect pest. To make the work more efficient, eight experts working at different institutions formed a team. At the same time, monitoring was begun on when and where the insect appeared and in what numbers. The experiments were adapted to the life cycle of the species. WCR has one generation per year, laying eggs that overwinter. Larvae begin to hatch in late May to mid-June. Adults emerge by mid-July and survive till early October. They lay eggs in abundance from mid-July to late August.  Trials were conducted to control WCR both with and without chemicals. For adult control pesticides were sprayed from an aircraft or using a field sprayer. Larval control involved seed treatment with insecticide or the use of soil insecticide at planting or at cultivation.

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The effect of high hydrostatic pressure (HHP) and nisin was studied on micro-organisms in minced chicken and beef meat. Pressure in the range of 0-800 MPa and nisin (670 IU g-1) were applied for vacuum packed minced meat. In chicken meat the total viable cell count decreased by 3 log cycles as an effect of HHP at 300 MPa and by 5 log cycles in combination with nisin. The D value is 35-39 MPa for pseudomonads in minced chicken meat. In case of inoculation with L. monocytogenes, the cell count in beef meat was reduced only by pressure higher than 200 MPa (“shoulder”) with a characteristic value of D=37-38 MPa. B. cereus spores, both dormant and heat activated, were very resistant (D=800 MPa) in beef. However, the survival of pressurised spores after chilled storage (for two weeks at 4 °C) was smaller for non-heat activated spores than for heat activated spores. Efficiency of HHP combined with nisin needs further research work.

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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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Acta Veterinaria Hungarica
Authors:
Andrea Bistyák
,
S. Kecskeméti
,
R. Glávits
,
I. Tischler
,
S. Nagy
,
G. Kardos
, and
I. Kiss

An epizootic of Pacheco’s disease is reported from a zoo bird population. The infection was introduced by wild-captured Patagonian conures ( Cyanoliseus patagonus ) despite 61 days of quarantine. The disease affected several parrot species and, interestingly, three out of seven bearded barbets ( Lybius dubius ). The mortality rate was 30.93%. Autopsy revealed abdominal hyperaemia with liver haemorrhages and, in less rapid cases, yellowish discoloration and fragility of the liver. Death was caused by the collapse of circulation. Histopathology demonstrated liver cell necrosis, disintegration of the lobular structure, and a few intranuclear inclusion bodies. Icosahedral virions were detected by electron microscopy. The virus was isolated in the allantoic cavity of embryonated chicken eggs as well as in chicken embryo fibroblast cell culture. A 281-bp-long fragment of psittacid herpesvirus DNA was detected by PCR in cell culture material and liver samples of the affected birds. To our knowledge this is the first report of Pacheco’s disease in bearded barbets as well as the first occurrence of Pacheco’s disease in Hungary.

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Abstract  

Aerosol samples collected around the Chilean site Lonquimay during major volcanic activities in January 1989 have been subjected to microPIXE measurements of 1 mm lateral resolution in the Debrecen Institute. Elemental concentrations relative to calcium have been determined for Al, Si, P, S, K, Sc, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Ba in 187 individual aerosol particles with the particle sizes between 15 mm and 1 mm. On the basis of a cluster analysis performed on the data set we defined eight clusters. Scatter plots for selected pairs of elements as Si/Al, K/Si, S/Cl, and Al/S elemental ratios that are considered as signatures characterizing types and mechanisms in volcanic eruption - have been compared with published data available in the literature for various volcanic sites.

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Acta Alimentaria
Authors:
L. Bujdosó
,
F. Budán
,
T. Varjas
,
L. Szabó
,
A. Csejtei
,
J. Iványi
,
A. Huszár
,
I. Arany
,
I. Kiss
, and
I. Ember

Peripheral blood stem cells (PBSC) could contribute to tissue regeneration through the ability to form somatic cells. CD34 positivity is regarded as stem cell (SC) or endothelial progenitor cell (EP) marker. According to literature natural substances could increase the release of CD34 positive (CD34+) cells. In this study we investigated the basic rate of CD34+ cells in peripheral blood of CBA/Ca (H-2k haplotype) and BALB/c inbred mice by flow cytometry. Then we treated the mice with a new mixture of medical herbs, and we measured the level of CD34+ cells at 1, 3, 6, 18 and 24 hours after the treatment. A biological rhythm in the untreated blood was detected. Moreover the used herbal compounds increased the number of CD34+ cells.Although SC number is individually and highly variable in peripheral blood, the fluctuation could be used as a biomarker like the other compounds of peripheral blood in different aspects in risk assessment.

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Acta Veterinaria Hungarica
Authors:
L. Sámi
,
Krisztina Ursu
,
J. McKillen
,
S. Kecskeméti
,
S. Belák
, and
I. Kiss

Specific oligonucleotide primers were selected and combined in a multiplex arrangement, in order to detect simultaneously three economically important porcine viruses by polymerase chain reaction (PCR). The pathogen panel was comprised of viruses that cause reproductive failure in infected herds: Aujeszky’s disease virus (ADV), porcine parvovirus (PPV) and porcine respiratory and reproductive syndrome virus (PRRSV). In order to reduce the time required for the detection of the pathogens, the assay was optimised to a RapidCycler PCR instrument. The multiplex PCR assay was shown to be specific, sensitive and rapid, because the results were read in less than 60 min after sample preparation. Due to its speed, efficiency and sensitivity, the described rapid multiplex PCR assay serves as a useful novel tool in the veterinary diagnostic laboratories for the quick and complex detection of these important porcine pathogens.

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