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Selection of powdery mildew resistant and susceptible grapevine genotypes with molecular markers
100-104Views:148Incorporation of competitive quality and resistance against the most important fungal diseases (powdery and downy mildew) in a cultivar is one of the most important aims of grapevine breeding. In the 20th century, the most advanced results in grapevine resistance breeding were achieved by French researchers. They used resistant cultivars in more than 30% of their growing areas. In these varieties, North American wild Vitis
species were the resistance gene sources. The discovery of immunity-like resistance of Muscadinia rotundifolia opened new perspectives in resistance breeding. M. rotundifolia harbours a dominant powdery mildew gene, providing resistance in highquality cultivars after back-crosses with V. vinifera varieties. M. rotundifolia has been involved in the Hungarian grape breeding programs since 1996, thanks to a French-Hungarian variety exchange. In addition to traditional selection methods, application of MAS (Marker Assisted Selection) based on various types of
molecular markers, can provide additional tools for these efforts. Run1 locus, responsible for powdery mildew resistance, was identified in Muscadinia rotundifolia. Molecular markers closely linked to this locus are very significant in screening progenies deriving from M. rotundifolia and V. vinifera crosses, making possible the discrimination between resistant and susceptible genotypes at DNA level. In our analyses BC5 progeny of {(M. rotundifola×V. vinifera) BC4}×Cardinal (V. vinifera) tested for powdery symptoms were analysed with PCR-RFLP (GLP1- 12P1P3) and microsatellite markers (VMC4f3.1, VMC8g9). Our results proved the applicability of the linked markers and reliability of marker assisted selection. -
The Fattening and Slaughtering Examination at the Hungarian Racka Sheep
37-42Views:102Fattening and slaughtering characteristics of both types (black and white) of the Hungarian racka sheep were investigated at the site of the National Institute for Agricultural Quality Control in Atkár. The Hungarian merino, the dairy cigaja and the British milksheep were applied as control groups. 10 animals were examined from both sexes in each genotype. The examination was carried out according to the principles set in the Codex for sheep breeding. During the test acute diarrhoea occurred in each control group. However, only few lambs were excluded from the test from the British milksheep and the Hungarian merino groups because of significant changes in their condition. Consequently, the results obtained were not significantly influenced. No symptoms of any illness could be recognised in the Hungarian racka sheep, though. The significance of the difference between the average of the examined groups were checked by T-tests.
Daily gain was significantly less compared to the control groups, except for the white racka males. The lambs starving for 24 hours before slaughtering weighed 25.3-30.0 kgs on average. The black and white racka females weighed the least while the Hungarian merino females weighed the most. The quantity of abdominal and kidney fat was significant in the case of our native females. The quantity of abdominal fat was significantly bigger compared to each control group. On comparing the investigated groups it turned out that the white racka males had the biggest skin weight while the white Hungarian racka females had the smallest, that is the two extremes were recognised in the same colour (white) of one bred. On qualifying the slaughtered animals females had better results than males in each bred; the racka sheep were better than the dairy cigaja but were worse than the Hungarian merino and British sheep groups.
The huge differences in the carcasses of the groups were seen clearly when chopping. Examining the leg, it was noticed that the native groups proved to be smaller than the control groups, except for the black racka males. As for the short loin, the Hungarian racka and the Hungarian merino sheep proved to be the best, whereas the dairy cigaja and the British milk males had much smaller ones. The results gained when investigating the rack were similar to those of the short loin. As far as the rib and shoulder are concerned, the black racka females and the dairy cigaja females had the worst results. After chopping, the right side was also boned in every group. The small proportion of bone in the case of racka sheep was easily noticeable that resulted in the fact that the white racka females had the highest quantity of short loin compared to the other groups. When examining the back quarter, the bone proportions of the 4 racka groups proved to be significantly less than those of the control groups but it was not true for the meat proportions. As for the front quarter meat, the racka males were prominent in the great shoulder meat and in the small proportion of bone. The quantity of the first quarter bone was the least in the case of racka sheep and was the biggest for dairy cigajas. This difference proved to be significant in most cases.
In short, the Hungarian racka groups had the best results in meat quantity, which was especially significant compared to the dairy cigaja sheep. However, the quantity of external fat increased. -
Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
9-14Views:291Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.
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Drought-induced Losses in Fruit Orchards
37-40Views:94Scientists investigating the causes of the extremities of climate that have become quite frequent in the Carpathian Basin over the past few years are quite often in doubts as to whether increased atmospheric warming and the shortage of rainfall are to be seen as recurrent natural phenomena under our climate, or the first signs of global warming. Climate anomalies have, to a certain extent, always been common in the Carpathian Basin. However, statistical data of the past few decades indicate that the rise in temperature and the fall in precipitation have, by now, become a tendency, which requires further in-depth scientific research.
The series of articles to be published in continuation of this paper endeavors to synthesize the research results and many years of experiences, in order to give an analysis of
I. The economic effects and the symptoms of drought in tree cultures
II. The possibilities of reducing the adverse affects of drought -
Changes of relative chlorophyll content at maize smut inoculated hybrids
55-58Views:271The leaf chlorophyll content analysis is important for several reasons. The natural or anthropogenic stressors directly effect on the chlorophyll content. Through the measurement of the chlorophyll content it is possible to obtain data concerning the physiological status of the plant, moreover the chlorophyll content is closely related to the nitrogen content, so it is linked to photosynthesis and the photosynthetic activity which determine biomass production.
One of the most common symptoms of plant diseases is the larger and smaller interveinal chlorotic areas. These might be local, or expand to the whole plant. There are multiply reasons of chlorosis such as reduction of chlorophyll content, unfavorable effects on the chlorophyll content,disorders regarding function of chloroplasts or ultimately destruction of the chloroplasts. Although such a chlorotic deviancy can contribute to significant losses in photosynthesis; however the underperformance photosynthesis of the sick plants is a more complex process.
As we unambiguously experienced during our investigations on common smut that the infected maize plants most common accompanying symptom was chlorosis on the leaves, so it is especially important to examine how the infection influenced on the chlorophyll content of different hybrids. -
Relation of availability and barley uptake of some potentially toxic elements
7-10Views:76A small-plot microelement load field trial was set up on brown forest clay soil with eight elements (Al, As, Cd, Cr, Cu, Hg, Pb, Zn), on 3 levels each (0/30, 90, 270 kg element ha-1). The soil was treated with soluble salts of elements once at initiation (1994). In the seventh year of the experiment (2001) winter barley was the test plant. The total element content was determined in plant samples (shoot, straw, grain) after microwave digestion using cc.HNO3+cc.H2O2. The element composition of the prepared samples was determined using ICP-MS technique. In the experiment toxic effects of treatments and yield loss could not be observed. Zn and As contents in barely shoots were only moderately increased by increasing microelement loads. Effects of Cr, Cu, Hg, Pb and Al treatments could not be observed. On the other hand, Cd accumulation was significant in the shoot. Cd content was also increased both in straw and grain. Results of this experiment prove that Cd remains mobile in the soil-plant system for a long time. Its accumulation can be observed both in vegetative and reproductive parts of plants without toxic symptoms and yield loss.
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The Effect of Grazing Intensities on Magnesium Contents
8-13Views:236Research was carried out on two areas of grassland in Hortobágy National Park, Hungary. Two herds of Hungarian Grey Cattle were kept in free range grazing and the effects of grazing pressure on the magnesium content of soil and ryegrass (Lolium perenne L) were determined.
Changes of plant available and total soil magnesium content under different grazing intensities did not show any evident tendency on the investigated grasslands. Different amounts of cattle faeces, urine and trampling had no effect on the magnesium concentration of ryegrass. We conclude that the magnesium content of ryegrass on both grassland sites as moderate grazing and overgrazing matches the requirements of cattle. Symptoms of magnesium deficiency of cattle will likely not appear. -
Investigation of the Resistance Against the Fusarium solani at Different Pea Varieties and Combinations of Breeding
157-160Views:39The Fusarium species are soil and polyphage parasits, and the rate of damage, caused by them, highly depend on interactions between climatic and edaphic factors and also on sensitivity of cultivars. Even though about 70-80 percent of the widely grown green peas cultivars is resistant to Fusarium oxysporum f. sp. pisi 1. race, the rate of Fusarium infections and severity of symptoms increased in the latest years. It is supposed that another Fusarium sp. the Fusarium solani has been spreading. The most exact way to study the cultivars in a provoking garden established in natural environment, where the pathogen is artificially enriched to a level, at which the cultivars can be distinguished according to their susceptibility. In the provoking garden the reaction against to Fusarium of our breeding lines and our registered cultivars and cultivars existed on the National List (including cultivars with well-known susceptibility as standards) are examined year by year. In our experiments we could found two green peas cultivars to be resistant to Fusarium solani (Early sweet (13,36%) and Lora (16,9%)) The breeding lines Margit and 8607/75-3-2 proved to be the most susceptible to Fusarium solani (94,4% and 73,1% infected plants, respectively).
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White rust species (Chromista, Peronosporomycetes, Albuginales, Albuginaceae) on common weeds in Hungary
30-33Views:232The obligate plant parasite fungi in the family Albuginaceae are responsible for causing white rust diseases on weeds and they are rather common worldwide. Weedy plants with characteristic symptoms have been collected in 2014 and 2015 on location Hajdú-Bihar and Jász-Nagykun-Szolnok counties in Hungary. The determination of the species were based on the morphological characters both pathogens and hosts. Albugo candida was determined on shepherd’s purse (Capsella bursa-pastoris). Common purslane (Portulaca oleracea) is a host for Wilsoniana portulacae. The fungus Wilsonia bliti (syn.: Albugo bliti), the causal agent of white rust disease was found on redroot pigweed (Amaranthus retroflexus).
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The Effect of Smut Gall Tumour Infection on Iron and Zinc Uptake and Distribution in Maize Seedlings
27-32Views:98The amounts of Fe, and Zn were measured in maize seedlings infected by smut gall tumour (Ustilago maydis Dc. Cda.) and in healthy seedlings five days after infection. The amount of elements was also measured under different stress intensities. Due to the infection, as a biotic stress, the amount and distribution of examined elements have been changed. On the bases of the differences in the Fe distribution between the symptoms less and tumorial leaf parts, we have come to the conclusion that the infection also effects the mobilisation of Fe and Zn inside the plants. The Fe uptake was much higher in the infected plants and the tumour development also had an effect on the uptake and distribution of the examined elements. The experiments of infecting maize seedlings by monosporidial strain of crown gall tumour showed no tumour development. We found that the monosporidial strain also acts as a biotic stress and has an effect of iron and zinc distribution. We observed a slight difference in the iron and zinc contents in the roots of corn seedlings infected by different monosporidial sporidium concentrations, while the iron and zinc contents in the shoots were increased by the intensity of the infection. The roots do not form tumours. There is no difference between the roots of the infected and healthy corn seedlings. Since the Fe and Zn contents of the shoots of infected plants depend on the intensity of the infection, we have come to the conclusion that there must exist a „special” communication system regulating the transportation of the examined elements.
In the experiments with infected maize seedlings, it became necessary to get the iron chlorosis before the disease reaches the lethal phase. Although most of the iron reserves are located in the embryo, to accelerate the chlorosis, the endosperm was removed, and it was observed, that the iron chlorosis appears later in maize seedlings when the endosperm is removed. The relative chlorophyll content of the first and second leaves was measured in iron efficient and iron deficient maize seedlings at different times.
The higher IAA content of tumorial plant tissues is already known. The treatment with IAA decreases the iron concentration in the shoots and in the roots of +Fe precultured plants and increases at -Fe precultured ones. The TIBA retards the shoot-to-root transport of IAA. When the seedlings were treated simultaneously with IAA and TIBA, higher iron concentrations were observed in the shoots and in the roots of corn seedlings.
We found extremely high iron concentrations in the roots of infected seedlings and, in line with this, serious damage to the roots was observed that this can be caused by the high iron content generated free radicals. The results demonstrate that IAA has a role in the shoot to root communication. -
Phytopatological properties of symbiotic Rhizoctonia solani strains associated to orchids
65-71Views:155The mycobiota of the Orchidarium of ELTE Botanical Garden (Budapest) has been studied applying aerobiological methods and isolating of tissue samples taken from 92 individuals of sixty orchid species. Among isolated basidiomycetaceous fungi 13 strains of Rhizoctonia solani were surviving in axenic culture. These symbiotic R. solani strains proved to be pathogenic on 24 cultivated plant species at varying degree. The symptoms of disease caused by R. solani strains isolated from orchids did not differ from that caused by reference strains. Three groups of strains could be separated regardless of their source or aggressivity. The host plants clustered into two groups, and their taxonomic position had no role in this respect. In general, we can assume that orchid associated Rhizoctonia strains are potential plant pathogens, and removed or withdrawn orchid stools should be treated as hazardous waste.
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The Impact of Water Supply on the Quality and Health of Potato
144-147Views:124Besides its effect on potato yield, water also has a significant impact on yield quality. Excess water (too much precipitation, over-irrigation) and the lack of water (lack of precipitation or irrigation) both trigger stress in the plant and can significantly worsen the quality of the yield (seed potato) and deteriorate the health of the plant and the seed potato. Excess precipitaton or irrigation water leaches nitrate-nitrogen under the rhizosphere, consequently, the amount of available nitrogen decreases leading to the deficiency of N in potato. If water cover (the maximally saturated state of soil) exceeds 8-12 hours, it can cause root destruction (because of the lack of oxygen), which leads to the wilting and later to the death of the plant. Abundance of water caused by excess precipitation or irrigation is a major problem primarily on sandy loam, loam and clay loam soils with bad structure and water management qualities, but also on any soils, which are over-irrigated or irrigated at an improper time. Symptoms of the lack of water are detectable mostly when the available water content of the soil (disponible water) decreases under 60-65%.
In the present year, there was a lack of precipitation on the Great Plain, which can be compensated by proper irrigation. Unfortunately, this problem is further intensified by the high temperature, which results in faster ripening and accompanied with fluctuating soil moisture content, in the formation of secondary tubers.