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  • Author or Editor: G. Kovács x
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In the present experiment the pollen viability of einkorn accessions of different origin was tested using four vital dyes (TTC, Baker's procedure, MTT and FDA) to determine the potential of the dyes to differentiate fresh living pollen from pollen heated for 12 hours at 80ºC (killed pollen). It was found that two of the four dyes previously employed to determine pollen viability also stained killed pollen in the case of several einkorn accessions, while FDA and MTT did not. It is thus suggested that the two latter should be used to test einkorn pollen viability, since they do not normally stain either killed or aborted pollen grains.

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G. G. Khachatourian, A. McHunghen, R. Scorza, Wai-Kit Nip, Y. H. Hui: Transgenetic Plants and Corps

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The Second Military Survey of the Habsburg Empire, completed in the 19th century, can be very useful in different scientific investigations owing to its accuracy and data content. The fact, that the mapmakers used geodetic projection and the high accuracy of the survey guarantee that scientists can use these maps and the represented objects can be evaluated in retrospective studies. Among others, the hydrological information of the map sheets is valuable. The streams were drawn with very thin lines that also ascertain the high accuracy of their location, provided that the geodetic position of the sheet can be constructed with high accuracy. After geocoding these maps we noted the high accuracy of line elements.The goal of this paper is to verify the accuracy of the rectified map sheets of the study area in order to test the applicability of such an analysis of the represented geomorphologic features like relief and streams. In the geomorphologic investigations high geometrical accuracy is needed due to the quantitative character of measurements. The study area is located at the Austrian-Hungarian boundary, south from Kőszeg Mountains/Günser Gebirge and west from Rába River/Raab Fluss.

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Using confocal microscopic analysis, FITC-labelled anti-a-tubulin antibody and the fluorescent taxol derivative Flutax-1 in fixed and living Tetrahymena pyriformis GL, longitudinal microtubules, oral and somatic cilia, deep fibers, and contractile vacuole pores were equally labeled. While the antibody stained transversal microtubules, these were not labeled by Flutax-1. At the same time, oral cilia were more intensely stained by Flutax-1, than by the antibody. There were no differences in the staining of fixed preparations and living cells. The observations suggest (i) the difference between the MAPs of longitudinal and transversal microtubules which allow or inhibit the binding of the indicator molecules, and (ii) the different functions of these two types of microtubules.

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In the course of gene bank research, problems frequently arise when valuable genetic materials have to be multiplied in an environment where the climatic conditions are quite different from those in its original habitat. In recently commenced experiments on the raising of emmer, the heading dates of two genotypes originating from different sources (MvGB 301 and MvGB 304) were investigated in a gradient growth chamber in the Martonvásár phytotron. This chamber allows precise information on the optimum temperature and light requirements of plants in different developmental stages to be obtained during the growth of a single generation. The data indicated that MvGB 301 headed considerably later than MvGB 304 at all temperature levels, but both varieties headed normally even at a constant very low temperature of 8°C. It was found that the light intensity had no influence on the heading dates of the two varieties.

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As a consequence of the recent spread of organic crop production, there is an increasing demand on the market for foodstuffs and food raw materials of special quality. New interest is being evinced in old cereal species that have been ignored for a long period, such as einkorn and emmer. Their production is hindered, however, by the fact that no breeding has been carried out on these species for long decades, and the landraces currently available are not suited to modern cultivation conditions. The breeding of varieties with the required habit is hindered by the lack of information on the plant structure of the various landraces and on the environmental dependence and inheritance of the characters that determine plant structure. Earlier studies suggest that inhomogeneous environmental systems can be used to identify the temperature and light conditions under which the phenotypic differences responsible for plant structure are the greatest, thus allowing the inheritance of these traits to be investigated. When two emmer landraces originating from diverse climatic regions (MvGB 301 and MvGB 304) were grown in a gradient phytotron chamber, it was found that relatively higher temperatures were more suitable for pinpointing differences in plant height, as the difference between the two varieties decreased parallel to a drop in temperature. Within the temperature range investigated it is advisable to choose the taller variety as basic breeding stock for organic variety development, as its height is closer to the ideotype for organic varieties. The length of the last internode in MvGB 301 is independent of changes in temperature, indicating that the phenotype is stable for this trait. The results clearly demonstrate that it is possible to find types of emmer which are morphologically adapted to the requirements of organic farming and have a plant structure relatively little affected by the genotype × environment interaction.

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The multiplication and characterisation of genetic stocks originating under very different ecological conditions is a problem constantly encountered in gene bank research. However, the major components of the original environment, such as temperature, light and humidity, can be reproduced under artificial conditions in the phytotron. The gradient, or inhomogeneous, chamber available in the phytotron of the Agricultural Research Institute of the Hungarian Academy of Sciences, Martonvásár, makes it possible to elaborate plant growth programmes optimised for the various developmental phases of each population in a single step. In this chamber gradients of two extremely important environmental factors, temperature and illumination, can be simultaneously programmed, thus allowing the optimum light × heat combinations to be identified. However, the use of complete inhomogeneity (light × heat) makes it extremely difficult to evaluate the experimental results, since biometric methods based on traditional statistics are unable to handle this situation. It is thus essential to find a method suitable for the comparative analysis of continual variables (Okada et al., 2000). The present paper reports on the first phase in the development of a plant growth programme for emmer, based on investigations made on two gene bank accessions of winter Triticum turgidum ssp. dicoccon (Schrank) Thell. (MvGB 301 and MvGB 304). In the gradient chamber study the accumulation of dry biomass in three-week-old plants was investigated as a function of temperature and light intensity. The results suggest that a temperature of 10-12°C combined with low or moderate light intensity is optimum for the germination and initial development (0-4 weeks) of emmer. These conditions also induced good tillering, which is extremely important, especially for gene bank accessions where the possibility of seed multiplication and field cultivation is limited.

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The aim of the work was to analyse the compostable properties of bone powder produced via different treatment methods and industrial conditions, and to study their effect on plant growth and phosphorus uptake. The bones were treated in water with different temperatures, bone-water ratios and treatment times. Further treatment was carried out with citric, nitric and sulphuric acid with different concentrations, temperatures, bone-water ratios and treatment times. Industrial bone powder was composted under model industrial conditions.The available phosphorus content of these materials was estimated using ryegrass ( Lolium perenne ) as indicator plant in a climatic chamber.The water-soluble phosphorus content of the bones increased in the citric acid and sulphuric acid treatment, depending on the water treatment conditions and the acid concentration. This increase amounted to about 30 times (0.32–8.51 mg/100 mg) compared to the water treatment.The results of the plant test demonstrated that the phophorus content of treated bone powder and compost was readily available to plants. The phosphorus content of the compost was available over a longer period.

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The objective of the present study was to determine the rostrocaudal distribution and the effect of reduced food intake (60% of the average daily food intake for 1-4 weeks) on the amount of leucine-enkephalin (Leu-enk), neuropeptide Y (NPY) and galanin (Gal) in the lateral septum of male rat brain. Using pre-embedding immunocytochemistry combined with densitometry on 60 mm serial vibratome sections we found that in control animals Leu-enk-immunoreactive elements showed an increasing density from rostral towards the medial part of the septum, then a gradual decrease towards the caudal direction. The distribution of NPY proved to be rather even along the examined sequence of sections with two smaller peaks roughly at the 1/3 and 2/3 of the rostrocaudal axis. Gal showed similar distribution but the peaks were shifted to more caudal direction. We also found that Leu-enk forms the most dense plexus followed by a moderate amount of NPY-positive axonal meshwork. Gal was present in the lowest amount along the lateral septal nuclei. The effect of reduced food intake was marked and differential in the case of the three examined peptides. During the first 2 weeks of reduced food intake NPY-immunoreactivity was upregulated as compared to the control, then it was reduced close to the control value by the 4th week. The changes in Gal immunoreactivity showed similar pattern. The average relative density of Leu-enk-immunoreactive elements immediately decreased as a result of reduced food intake for 1 week and it gradually decreased by the end of the 4th week. These results indicate that reduced food intake affects the expression of NPY, Gal and Leu-enk not only in the relevant hypothalamic neuroendocrine centres, but also in the lateral septal area.

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There is still disagreement among scientists on the exact origin of common wheat (Triticum aestivum ssp. aestivum), one of the most important crops in the world. The first step in the development of the hexaploid aestivum group (ABD) may have been hybridisation between T. urartu (A), as pollinator, and a species related to the Sitopsis section of the Aegilops genus (S) as cytoplasm donor, leading to the creation of the tetraploid species T. turgidum ssp. dicoccoides (AB). The following step may have involved hybridisation between T. turgidum ssp. dicoccon (AB genome, cytoplasm donor), a descendant of T. turgidum ssp. dicoccoides, and Ae. tauschii (D genome, pollinator), resulting in the hexaploid species T. aestivum ssp. spelta (ABD) or some other hulled type. This form may have given rise to naked types, including T. aestivum ssp. aestivum (ABD). The ancestors of the tetraploid T. timopheevii (AG) may have been the diploid T. urartu (A genome, pollinator) and Ae. speltoides (S genome, cytoplasm donor). Species in the timopheevii group developed later than those in the turgidum group, as confirmed by the fact that the G genome is practically identical to the S genome of Ae. speltoides, while the more ancient B genome has undergone divergent evolution. Hybridisation between T. timopheevii (AG, cytoplasm donor) and T. monococcum (A m, pollinator) may have resulted in the species T. zhukovskyi (AGA m). Research into the relationships between the various species is of assistance in compiling the taxonomy of wheat and in avoiding misunderstandings arising from the fact that some species are known by two or more synonymous names.

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