17 research outputs found
Testing a Possible Way of Geometrization of the Strong Interaction by a Kaluza-Klein Star
Geometrization of the fundamental interactions has been extensively studied
during the century. The idea of introducing compactified spatial dimensions
originated by Kaluza and Klein. Following their approach, several model were
built representing quantum numbers (e.g. charges) as compactified space-time
dimensions. Such geometrized theoretical descriptions of the fundamental
interactions might lead us to get closer to the unification of the principle
theories.
Here, we apply a dimensional theory, which contains one extra
compactified spatial dimension in connection with the flavour quantum
number in Quantum Chromodynamics. Within our model the size of the
dimension is proportional to the inverse mass-difference of the first low-mass
baryon states. We used this phenomena to apply in a compact star model -- a
natural laboratory for testing the theory of strong interaction and the
gravitational theory in parallel.
Our aim is to test the modification of the measurable macroscopical
parameters of a compact Kaluza-Klein star by varying the size of the
compactified extra dimension. Since larger the the smaller the mass
difference between the first spokes of the Kaluza-Klein ladder resulting
smaller-mass stars. Using the Tolman-Oppenheimer-Volkov equation, we
investigate the - diagram and the dependence of the maximum mass of
compact stars. Besides testing the validity of our model we compare our results
to the existing observational data of pulsar properties for constraints.Comment: 10 pages, 2 figure
Study of yield components under heat stress conditions in wheat
High temperature tolerance can be characterised by
measuring various plant productivity traits in different
developmental stages. The present work investigated the
effect of exposure to high temperature (30-35°C) at first
node appearance, during early embryo development and
in the grain-filling stage on the yield parameters of two
winter wheat varieties. Periods of high temperature had
diverse effects on wheat plants in different phenophases.
The greatest differences between the various developmental
stages were found for grain number, grain yield
and thousand-kernel weight. Heat stress was demonstrated
to have the least effect on total grain number and
number of grains per spikelet on the main spike during
the grain-filling period. The most pronounced reductions
in the traits examined were detected when heat stress
was applied during the early embryo development stage
EFFECT OF HEAT STRESS ON THE PHYSIOLOGICAL PROCESSES OF WHEAT
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
Investigation of the Stress Tolerance of Winter Wheat Genotypes Under Natural Rain-Fed and Irrigated Conditions
AbstractDrought around the world is one of the most important yield reducing factor. From the cross of winter wheat varieties (Plainsman V x Mv Magma) doubled haploid (DH) population was created consisting of 174 lines to investigate the drought tolerance of the genotypes exposed to two treatments; natural rain-fed and well-watered conditions in the field.The object of the experiment was to determine the yield production capacity of the DH lines under natural rain-fed conditions and to compare the effect of changes in the yield components due to irrigation. After ripening, the wheat plants were harvested from both treatments. The plant height, the length of last internode, number of spikelets, seed number, seed weight on the main stem; the number of reproductive tillers, seed number and weight per plant was determined.The effect of irrigation was investigated on the morphological parameters and yield properties which changed due to well watered conditions in the wheat plants. Averaged over the DH lines, the heading date was significantly affected by irrigation. Irrigation significantly increased all the morphological parameters. Not only the average, but also the minimum and maximum values increased significantly for spikelet number, reproductive tiller number and plant height. Changes in the morphological parameters resulted in significant alterations in the yield components. The irrigation significantly increased the total grain number per plant, the thousand kernel weight and the grain yield averaged over the DH lines.The results showed that the morphological parameters and yield components can still be some of the most effective features to estimate the tolerance of wheat in response to stress factors. This project was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences and the project DROPS (EU-FP7 No. 244374)
Rising atmospheric CO2 concentration may imply higher risk of Fusarium mycotoxin contamination of wheat grains
2
Abstract
Increasing atmospheric CO2 concentration not only has a direct impact on plants but also affects plant-pathogen interactions. Due to economic and health-related problems, special concern was given thus in the present work to the effect of elevated CO2 (750 μmol mol-1) level on the Fusarium culmorum infection and mycotoxin contamination of wheat. Despite the fact that disease severity was found to be not or little affected by elevated CO2 in most varieties, as the spread of Fusarium increased only in one variety, spike grain number and/or grain weight decreased significantly at elevated CO2 in all the varieties indicating that Fusarium infection generally had a more dramatic impact on the grain yield at elevated CO2 than at the ambient level. Likewise, grain deoxynivalenol (DON) content was usually considerably higher at elevated CO2 than at ambient level in the single-floret inoculation treatment, suggesting that the toxin content is not in direct relation to the level of Fusarium infection. In the whole-spike inoculation, DON production did not change, decreased or increased depending on the variety × experiment interaction. Cooler (18°C) conditions delayed rachis penetration while 20°C maximum temperature caused striking increases in the mycotoxin contents, resulting in extreme high DON values and also in a dramatic triggering of the grain zearalenone contamination at elevated CO2. The results indicate that future environmental conditions, such as rising CO2 levels, may increase the threat of grain mycotoxin contamination.
Keywords: deoxynivalenol, elevated CO2, Fusarium culmorum, mycotoxin, Triticum aestivum, zearalenon
Differences in the associations between psychoactive substance use and alexithymia:A series of meta-analyses
Heat stress responses in a large set of winter wheat cultivars (Triticum aestivum L.) depend on the timing and duration of stress
Modern agriculture depends on the production of very few crop species, which provide lower nutritive value for consumers. The present work summarizes the results of a three-year experiment on hulled wheat varieties as potential candidates for food system diversification. The organic field cultivation tests with 10 emmer and five einkorn landraces and varieties were conducted on similar to 10 m(2) plots on sandy soil, and from 2017, under on-farm conditions in eastern Hungary. Most accessions adapted well to the marginal conditions, with some landraces even yielding higher than registered varieties-over 3 t per ha on average over three years. Compared to emmer, einkorn had higher maximum grain yields, but its yield performance varied more than that of emmer. Grain protein and the total phenolic content were high in both species. Compared to emmer, einkorn seeds exhibited a 3.8 times higher content of bound flavonoids and had 3.4 times higher antioxidant activity. Four einkorn accessions were resistant to leaf spot, as well as yellow and leaf rusts. Fusarium infected both species similarly. Our findings indicate that not only registered varieties of ancient wheat species but also their landraces can provide sustainable alternatives both for organic farmers and also for the diversification of agriculture