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Six single-cross hybrids and their parental lines were inoculated with the FG36 Fusarium graminearum isolate in 2005 and 2006. In both years the degree of infection increased after artificial inoculation for both the hybrids and the inbred lines compared with the level of natural infection. The more severe stalk infection recorded in 2005 than in 2006 could be attributed to the weather conditions during flowering and harvesting.The 18 genotypes examined exhibited different levels of resistance to fusarium stalk rot. It could be concluded from the results that the resistance level of the female parent was decisive in the inheritance of the response to fusarium stalk rot (female component-hybrid r = 0.88, male component-hybrid r = 0.39).Some genotypes may be severely affected in epidemic years, while exhibiting a lower rate of infection in years with lower pathogen pressure. This suggests that successful breeding for resistance can only be carried out efficiently by means of artificial inoculation.

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Community Ecology
Authors:
K. Pintér
,
Z. Barcza
,
J. Balogh
,
Sz. Czóbel
,
Zs. Csintalan
,
Z. Tuba
, and
Z. Nagy

Interannual variation of carbon fluxes of grasslands on sandy (5 years data) and heavy clay soils (4 years data) have been analysed. The sandy grassland was carbon sink in 3 (2004, 2005, 2006) out of the investigated 5 years. Its annual C-balance is precipitation limited, the relation seems strongly conservative, with r 2 of 0.83. More than half of the net source activity fell to the summer droughts. The heavy clay grassland was net source of carbon in one year (2007) only with no whole year record from 2003, a drought and heat wave year. Dependence of the C-balance on precipitation was somewhat weaker (r 2 =0.57) than in the sandy grassland. Length of growing period showed less variation here compared to the sandy grassland. Recovery of sink activity after rains was much slower for the heavy clay grassland than for the sandy grassland. The reason behind is that the amount of water required to reach optimal soil water content for plant functioning is several times larger for the mountain grassland. This fact and the low conductivity of the clay soil for water decrease the heavy clay grassland’s recovery potential after droughts. Owing to these soil characteristics, the clay grassland may be more vulnerable to droughts in terms of decreased C-assimilation and (soil) carbon losses under the predicted drier summers even if the annual precipitation sum was higher by 10.7% on average for the mountain compared to the sandy grassland. The annual precipitation sum is close to the threshold, below which the grasslands may turn into source of carbon. While in one hand this can be viewed as an example of ecosystem scale adaptation to available water, drought events also involve loss of soil carbon and a potential positive feedback between source activity and decreasing net primary production, on the other.

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Soil fluxes of methane and nitrous oxide were determined for grasslands on sandy, loess and clay soils in Hungary. As the direction of methane flux (emission or uptake) depends on the soil characteristics bi-directional fluxes were observed. For sandy and loess grasslands the sink and source processes are practically balanced showing a negligible low mean methane flux for 2006–2007 (−0.04–0.05 kg CH 4 ha −1 yr −1 ). In this period the clay grassland functioned as a weak sink for methane (−0.34 kg CH 4 ha −1 yr −1 ). Average soil nitrous oxide emission fluxes for the period of 2002–2006 was 0.5 kg N ha −1 yr −1 for sandy and loess while 0.2 kg N ha −1 yr −1 for clay grassland, respectively, with substantial inter-annual variations. Taking into account the total atmospheric N-input 0 to 8 per cent of deposited nitrogen is emitted from the soils in the form of N 2 O as the intermediate product of soil denitrification processes.

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Abstract  

Within the frame of a joint project, the accumulation of the uranium and transuranium (TRU) species on some structural materials used at Soviet made VVER-type pressurized water reactors (such as heat exchanger tube of steam generators and stainless steel canister material) has been studied. The experiments were carried out in a laboratory model system. During the sorption studies, boric acid coolants provided by the Paks Nuclear Power Plant (Paks NPP) were circulated for a period of 30 h. Solution and tube samples obtained in the course of above experiments were analyzed by independent methods (α- and γ-spectrometry, ICP-MS, SEM-EDX, voltammetry and XPS). The experimental results reveal that: (i) the surface excess of the TRU nuclides studied is extremely low (less than 1% of a monolayer coverage); (ii) the surface excess of uranium species measured on the SG tube surfaces is significantly higher, after 30 h sorption period (Γsample = 1.0 μg cm−2 U ≅ 3.7 × 10−9 mol cm−2 UO2) exceeds a monolayer coverage; (iii) the mechanistic features of the contamination processes (specific or non-specific adsorption, deposition of colloidal and/or disperse particles) depend decisively upon the nature of the studied radionuclides and the chemical structure and composition of the oxide layer formed on stainless steel surfaces.

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Acta Alimentaria
Authors:
B. Raposa
,
E. Antal
,
J. Macharia
,
M. Pintér
,
N. Rozmann
,
D. Pusztai
,
M. Sugár
, and
D. Bánáti

Abstract

Several misconceptions exist about foods and nutrition. Many believe, that the human body can “acidify”, thus, an “alkaline diet” should be followed. The acid-base balance is a characteristic of a normally functioning human body. Throughout our metabolic processes, acids and substances with acidic pH are produced continuously, which, in the case of a healthy person, does not affect the pH of the human body. In those rare cases, when an overall pH imbalance evolves in the human body due to its life-threatening nature, it requires urgent medical intervention. Furthermore, it cannot be influenced by dietary interventions.

This paper highlights evidence regarding acidification and the acid-base balance, with special attention to certain food groups. Foodstuffs have different specific pH value (acid-base character), they can be acidic, alkaline, or neutral in elemental state. Beside their chemical nature, the effect they have on the human body depends on the mechanism of their metabolism, as well. Diet and ingredients have direct and indirect effects on the human body's intracellular and extracellular compartments (especially blood and urine), still they do not influence its pH significantly.

Alkaline diets were born in the absence of evidence-based information and/or the misunderstanding and wrong interpretation of the available and up-to-date scientific facts. The convictions of consumers and the promotion of the alkaline diet lack the scientific basis, so it can be harmful or even dangerous in the long run.

In summary, scientific evidence on the efficacy or prophylactic effects of an alkaline diet is not available.

Open access
Acta Agronomica Hungarica
Authors:
J. Pintér
,
E. Kósa
,
G. Hadi
,
Z. Hegyi
,
T. Spitkó
,
Z. Tóth
,
Z. Szigeti
,
E. Páldi
, and
L. Marton

The level of UV-B radiation reaching the surface of the earth is increasing due to the thinning of the ozone layer in the stratosphere over recent decades. This has numerous negative effects on living organisms.Some of the Hungarian inbred maize lines examined under the climatic conditions in Chile exhibited an unusually high proportion of pollen mortality, flowering asynchrony and barrenness. The evidence suggests that this can be attributed to the approx. 30% greater UV-B radiation in Chile.The investigation of this problem within the framework of abiotic stress breeding programmes is extremely important in the light of the global rise in UV-B radiation, which may make it necessary to elaborate a selection programme to develop inbred lines with better tolerance of this type of radiation.In the course of the experiment the same ten inbred lines, having different maturity dates and genetic backgrounds, were tested for five years in Chile and Hungary. The tests focussed on anthocyanin, a flavonoid derivative involved in the absorption of damaging UV-B radiation.Averaged over years and varieties, the total anthocyanin content in the leaf samples was significantly higher in Chile than in Hungary. This was presumably a response at the metabolic level to the negative stress represented by higher UV-B radiation.In the five early-maturing flint lines the anthocyanin contents were more than 45% greater than those recorded in Hungary. This suggests that these genotypes, originating from northern regions, were not sufficiently adapted to the higher radiation level. In these samples higher UV-B caused a sharp rise in the quantity of anthocyanin, which absorbs the dangerous radiation. In late-maturing genotypes the initial content of the protective compound anthocyanin was higher at both locations, so in these types the high radiation level was not a problem and did not cause any substantial change.Similar conclusions were drawn from the results of fluorescence imaging. The F440/F690 ratio indicative of the stress level was higher in late lines with a high anthocyanin content, good tolerance and good adaptability.

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Abstract

A plethora of research and empiric observation supported the claim that–among other symptoms–diseases often affect the ability to smell and the sense of taste, possibly affecting the taste- and food preferences as well.

The aim of the present study was to shed light on the impact of COVID-related smell- (dysosmia/anosmia) and taste function-disorder/loss (dysgeusia/ageusia) on the food and taste preferences COVID-19 patients of different symptomatic and pre-existing conditions and demographic backgrounds.

The research based on a descriptive, cross-sectional survey. In total, 514 participants filled our self-administered online questionnaire. Thirteen participants were excluded according to the exclusion criteria. Descriptive statistics, Chi-square test, t-test for correlation coefficient, were performed.

The most common long COVID symptom was fatigue/weakness (53.1%) followed by anosmia (50.9%) and tachycardia (33.5%). Many participants reported dysgeusia/ageusia during the acute phase of the disease, which sometimes prevailed as a long COVID symptom. A high percentage of participants reported that they rejected all kinds of meat of animal origin except cold cuts for their duration of recuperation, which proved to be the most common dietary change during the post-COVID period so far.

Open access