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Influence of 17-alpha methyl testosterone on the production parameters of common carp (Cyprinus carpio L.) fry
37-43Views:221During our research we aimed at finding an answer as to what extent the different concentrations of 17-alpha methyl testosterone incorporated in the diet of common carp fries can influence the production parameters of the species, as well as how efficient their sexreversal can be with the use of this method. To this end, an aquarium experiment was conducted in the course of which four different hormone treatments were set and monitored. The fish feed was enriched with 17-alpha methyl testosterone in 50 ppm, 75 ppm, 100 ppm, 500 ppm dosages.
The obtained figures revealed that the hormone treatments had no influence on the production parameters and conservation of the common carp fries. Further on, our team is to determine the sex of the fish through the examination of gonads during autopsy when they reach the 500 g average weight.
Furthermore, a male specific test method which was supposed to be of great help in our attempt to select the sex-reversed specimens in the subsequent processes was also put to the trial. During the experiment the DNA-isolation of different sample types (muscle tissue, fin, mucus) of common carp with identified sex was successfully carried out. The extracted PCR product was examined with agarose gel. Our results indicated that the ccmf2 marker was applicable, however, the obtained figures were not reliable.
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Effect of different weaning time on the growth and survival ofCommon carp (Cyprinus carpio L.) larvae
55-59Views:280Within our experiment, we studied the combined effect of live food application and feed training on the production parameters of carp larvae. In addition, we examined whether there is a difference in the growth rate and survival rate of the specimens of Szeged mirror landrace reared in similar stocking density but with different treatments.
Specimens of Szeged mirror landrace from induced propagation were placed into 12 pieces of 40-liter aquaria. For the 4 different treatments, (K, A3, A6, A9), live food (Artemia salina) was fed, as well as feed training was applied.
We also sought to find an answer as to how our feeding and rearing conditions can affect the production parameters of common carp fries and what impact these conditions may have on their survival rates. At the end of the 2-week experiment we determined the individual weight gain of the carp fries, their survival rate and the biomass growth. The purpose of the study is to examine the optimum timing of shifting from live food to feed for carp larvae.
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The role of production site isolation in the plant health situation of sweet chestnut (Castanea sativa)
79-82Views:146The most destructive pathogen for the European chestnut is the blight fungus Cryphonectria parasitica (Murr.) Barr. The spread of the fungus was very fast in Europe within a few decades in the second half of the past century. During the tree-health checking in the chestnut and
walnut plantation in Romania, Hargita county, next to Homoródkarácsonyfalva village, we especially concentraded on the signs of blight disease occurrence. The grove is laying on a western slope, under a pine forest. This favourable geographical space protects it not only from pathogen attacts, but it has a special, mild microclimate for nut and chestnut trees. The European chestnut could be a valuable member of local forests, opening a new perspective under conditions of climate changes. -
Effect of the media on morphology of Cryphonectria parasitica (Murr.) Barr isolates and their Vegetative Compatibility Groups
38-42Views:149The most dangerous pathogen for the European and American chestnuts is the blight fungus Cryphonectria parasitica (Murrill) Barr. Short after its introduction a big number of chestnut trees were destroyed on the infested area. The control could be really complicated, because of the numerous vegetative compatibility groups of the fungus. There is a type that carries a mycovirus viz. hypovirus in the cytoplasm. We are able to control effectively this pathogen by using mycovirus-carrying strains (called hypovirulent fungal strains also). In laboratory it is easy to multiply the virulent and the hypovirulent strains of the fungus but do not easy to differentiate colonies visually on simple PDA medium. During our research, we tested different types of media, based on potato and chestnut bark extract respectively. It was observed that on potato medium the virulent strains produce more orange pigments. So it is more easy to differentiate virulent or hypovirulent isolates of chestnut blight fungus based on colony colour and morphology.
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Biological control of sweet chestnut on Pécsbánya, Hungary
77-81Views:194The supervision of plant hygiene of sweet chestnut grove on Pécsbánya (South Hungary) started more than four years ago. Hypovirulent strains were applied as a biological process to control Cryphonectria parasitica fungus which causes the chestnut blight disease. By now the performed interventions have shown obvious results, the vitality of the trees has greatly improved, the amount of harvested nuts is increasing, and the hypovirulent strain has been spreading within the area. During plant health inspection the galls of chestnut gall wasp (Dryocosmus kuriphilus) was found in the year of 2015, which is the obvious symptom of new occurrence of the pest. The pest was eradicated by destroy galls, which allows taking out of consideration the damage by now in this area.
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75 years of the chestnut blight fungus Cryphonectria parasitica (Murr.) Barr in Europe
82-85Views:171The chestnut blight fungus Cryphonectria parasitica is a native pathogen in East Asia and has been introduced into North America and Europe. Historical records and population genetic studies revealed at least three major introduction events from Asia into Europe.
Nowadays, chestnut blight is present in almost the entire distribution range of European chestnut, i.e. from the Iberian Peninsula to the Caucasus. The C. parasitica population in most countries has been studied in respect to the diversity of vegetative compatibility (vc) types and the occurrence of hypovirulence. The vc type diversity of the different populations varied considerably. Typically, a high diversity of vc types has been found in areas with a long history of chestnut blight and where sexual recombination between divergent genotypes commonly has occurred. On the other hand, newly established populations often showed a low diversity with only one, or a few vc types present.
Hypovirulence, i.e. the occurrence of C. parasitica isolates infected by Cryphonectria hypovirus 1 has been found widespread in Europe. Natural dissemination and active biological control applications have lead to a high prevalence of the hypovirus and to the recovery of many chestnut stands. Virulent cankers became hypovirus-infected within a short time and ceased expansion. There is concern that the diversity of vegetative compatibility types could increase in Europe through sexual reproduction between C. parasitica genotypes originating from different introductions. A higher level of vegetative incompatibility would not only hamper hypovirus spread within a population but could also select for lower virulence in CHV-1 and subsequently lead to an erosion of biological control. Recent studies, however, indicate that the vc type barriers are not so restrictive than previously assumed and that so far no evidence for an erosion of biological control system in high diversity populations can be observed.
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Chestnut tree: an appropriate choich for rural developement in Europe (review)
55-59Views:121In chestnut plantations or in associations many pathogens and pests can be found. They are causing more than a hundred year problem in chestnut protection, for example the blight fungus Cryphonectria parasitica. Lot of breeders hybridized the Castanea sativa and Castanea dentata with the tolerant asian species. Nowadays the presence of Dryocosmus kuriphilus seems to be the main risk. However, there are more and more chestnut plantations in Europe because of the extensive growth of needs. The food industry produces many products from chestnut, but the wood industry also use it more and more. In most of European countries the chestnut stands represent landscape aesthetics and touristic value, but probably the number of farmers inquiring the plantation will be increase in Hungary.
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The specification of the growing temperature on PDA of chestnut blight pathogen (Cryphonectria parasitica (Murr.) Barr) to optimize timing for biocontrol treatments by hypovirulent strains
29-32Views:161The most destructive pathogen for the European chestnut trees is the blight fungus Cryphonectria parasitica (Murr.) Barr. The biological control is the only effective possibility to apply in situ biocontrol by hypovirulent strains against compatible virulent (wild) fungus strains. The infested bark tissues can inoculate by drilling holes surrounding and putting into agar discs interwoven by the appropriate vegetative compatible group (VCG) hypovirulent fungus strains. This latest can pass those virus-like particles (VLPs) by parasexual contact (called hypha-anastomosis)which responsible to hypovirulence. A laboratory experiment was made to find the optimal times to carry out the treatments. The intensity of growth of fungal colonies were analysed on different temperatures. The growth of the fungus on low temperature were rather slow,according to our expectations. On higher temperature the colony progress were the same as on the optimal 20–25 °C. These observations and the environment determine the date of the field applications under Hungarian weather conditions. It means the optimal treatment periods can be May or end of September to middle October in Hungary.
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Comparision of growth of mature all-female and mixed-sex Common carp (Cyprinus carpio L.) stocks in RAS
65-68Views:422The common carp (Cyprinus carpio L.) is the most important fish species in Hungary, it is more than 70% of the total Hungarian fish production. The common carp production is important not only just in Hungary but in Middle-East Europe, as well as Southeast Asia. Majority of the production comes from fishpond culture. If the production sector wants to meet the increasing customer demands, there is need to intensify research on the intensive fish production opportunities for example all-female common carp technologies. The all-female technology is one of a genom-manipulation technology. Its production showed better growth rate than mixed-sex population in pond culture. Our experiment combined the recirculation aquaculture system (RAS) and the all-female common carp stocks intensification technologies. The reason for the experiment, is that there are no result about the growth of all-female common carp growth in RAS.
The experiment used the „Tatai grey scale type” common carp stocks. We propagated two all-female stocks (T2 and T3) and a control group (TK). Due to technological characteristics of RAS, the water quality parameters were the same for all treatments and corresponded to the technological tolerance of common carp.
The experimental period was from July 10, 2019 – November 20, 2019. Result of growth performance showed that the growth of mixed-sex stock was significantly higher than all-female stocks; (Control=3692.0±590.5g, T2=3438.8±415.4g, T3=3294.1±659.1g). Feed conversation ratio (Control=1.3±0.1 T2=1.5±0.2 T3=1.6±0.5) and SGR% (Control=0.8±0.0 T2=0.7±0.1 T3=0.7±0.1) were similar.
By the results it can be said the all-female common carp technology has neither advantages nor disadvantages compared to the mixed-sex stock. The all-female technology can be beneficial if the consumers need female common carps. It is worth continuing the experiment and examine how the stocks will perform above 3kg body weight.
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The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
89-96Views:275Aquaponics is an integrated system that combines fish farming (aquaculture) and hydroponic plant production. The objective of this study was to examine how the level of dissolved oxygen with or without an air pump affects water quality, fish output and plant growth parameters for common carp (Cyprinus carpio) and basil (Ocimum basilicum).
Ebb – and flood aquaponics systems (with automatic syphon) was used. Two treatments were set in this experiment, one of which was the aquaponics system without air pump (unit I), where water of the plant bed was pumped two directions, one falling back to the fish tank oxygenating the water the other was pumped to the hydroponics unit. The other system (unit II) was designed with an air pump.
In the course of the study, water quality parameters, such as oxygen saturation, dissolved oxygen (DO), electrical conductivity (EC) and nitrite were significantly different (p<0.05). Total basil biomass was higher in unit II. (5367.41 g). The final biomass of common carp were
2829.45 g ± 79.24 and 2980.6 g ± 64.13 g in unit I and unit II respectively. Weight gain (WG) and specific growth rate (SGR) showed no significant differences (p>0.05) between the treatments. -
Comparison of the technological background of aquaponic systems
47-52Views:260Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, an ecologically sustainable horticultural production technique with long traditions.
The objective of this study is to compare flood-and- drain, and the water crossflow system and examine the differences in the water quality, fish yield and plant growth parameters for Common carp (Cyprinus carpio) and basil (Ocimum basilicum). During the study, water quality parameters of two treatments were compared in temperatures, pH, EC and NO3¯N were significantly different (p <0.05). Leaf area of the basil plants grew to an average of 20.37 cm2 (± 9.02 cm2). The plants’ biomass production was significantly different (p< 0.05) in the two systems. The biomass production showed lower yield, 458.22 g (± 214.59 g) in the constant flow system that in the flood- and- drain system 692.9 g (± 175.82 g). Fish Growth parameters were better in constant flow system (FCR 5.48 g/g ± 0.19). However, the specific growth rate (SGR) demonstrated that fish grew faster in flood- and- drain system 1.38 %/day (± 0.29).
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A partial botanical survey of a gamepreserve
27-30Views:173Hungary is internationally well known for its high level game management. An important part of game management is indoor game keeping. In Hungary more and more game preserves were founded all over the country. The role of these game preserves to retain forest stands outside of the closed area. According to the law, in the game-preserves the game bearing capacity is not the most important parameter, because in these areas the feeding is continuous. In practice it means that in game-preserves we find a much higher density of games than in nature. This causes a relative big loading of the area (of the herbaceous and arboreal), where the game-preserves are located. Our aim is to study the ecological and management issues of forest- and game resources. The scene of these work is a game-preserve related to the Nyírerdő Corporation (Nyíregyháza).
We have done a botanical survey (plant coverage, life-form spectrum) in the three previous units and in the control area (outside of the game-preserve) as well. Our results show the difference in case of the state of herbaceous plants between areas with higher and lower game density. -
Comparative Evaluation of the Temperaments of Charolais and Hungarian Grey Steers
14-19Views:84Animal breeding increasingly lays claim to the theoretical and practical knowledge of applied ethology. The authors’ aim was to evaluate and compare the temperaments of Charolais (CH, n= 10) and Hungarian Grey (HG, n= 10) steers, and also to determine the correlation between their temperament scores and flight speed scores. Temperament was evaluated by the results of the scale test (assessing of behaviour in a 1-5 score system, while the animal is standing on a scale for 30 seconds) and flight speed test (minutes it takes the animal to move a set distance of 1.7 m when leaving the scale), on three occasions (1, 2, 3). Data management was done by SPSS.10 (ANOVA, Mann-Whitney-test, Spearman-correlation). Results of the scale test differed significantly between breeds at the third measurement (CH: 2,9 scores; HG: 1,4 scores; P<0,01) and when evaluating the three measurements together (CH: 2,0 scores; HG: 1,37 scores; P<0,05). Concerning of flight speed score, there were significant differences between breeds of steers at each measurement (1. measurement CH: 2,77 s; HG: 4,09 s; P<0,05; 2. measurement CH: 2,89 s; HG: 5,01 s; P<0,01; 3. measurement CH: 2,46 s; HG: 5,33 s; P<0,01) and overall (CH: 2,71 s; HG: 4,81 s; P<0,001). In the case of both breeds, evaluated by measurements and overall, a negative correlation was calculated between temperament score and flight speed score, but this was significant only in three cases: CH1 (n=10) r= -0,75; P<0,01; CH1+2+3 (n=30) r= -0,44; P<0,05; CH+HG1+2+3 (n=60) r= -0,33; P<0,01). Results indicate that Hungarian Grey steers are calmer than individuals of Charolais. Animals behaving calmer on the scale left the scale, more slowly. The authors propose the use of these temperament tests in Hungarian breeding practice, in order to select too temperament animals.
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Review of research on salt-affected soils in the Debrecen agricultural high educational institutions, with special focus on the mapping of Hortobágy
471-484Views:65The history of the research of Debrecen scholars on salt-affected soils of Hortobágy and the region is very rich and diverse.
Focusing on mapping, the following stages can be distinguished, indicating the completeness of the maps and the purpose of the performed work
− First, quantitative maps (Arany, 1926) for the utilization of the lands at 1:75,000 (Figure 1).
− Second, quantitative map (Kreybig, 1943) for the utilization of the lands at 1:25,000.
− Third, category map (Kreybig et al., 1935) testing the suitability of the classification system at :75,000.
− Fourth, partial category map (Szabolcs, 1954), showing the reasons of unsuccessful management at 1:10,000.
− Fifth, partial quantitative map (Csillag et al., 1996), showing the utility of digital sampling at 1:25,000.
− Sixth, partial quantitative map (Tamás and Lénárt, 2006), showing the capacity of multispectral remote imagery at 1:100.
− Seventh, partial quantitative map (Douaik et al., 2006), showing the usefulness of geostatistical mapping at 1:10,000.
− Eight, national quantitative maps (Pásztor et al., 2016), showing the applicability of geostatistics for administrative purposes at 1:10,000.
− Ninth, partial quantitative/category map (authors, 2019), finding the optimal methods at 1:10,000. -
SIM Samples Investigation by Statistical Methods
194-197Views:60The assessment of the present condition of the soil is very important, because the accession of the number of the European Union members is in the near future. This can be the base of the modern agrarian environmental management programme. The assessment must be objective, detailed and analyse the processes in the soil.
Respecting the above causes was decided to create an Environmental Information Monitoring System. This system consists of more parts. One of them is the Soil Information Monitoring System (SIM). This system started to work in 1992.
This system has two functions. Creating and actuation is obligatory from the international contracts, on the other hand the public SIM has very important role in the conservation of the soil.
The SIM territorial measuring grid consists of 1236 measuring points. These points are representatives. The distributions of the points by the types of soil attend the variety of the types of soil of the country.
The investigated elements in 6 types of soil were in our experiment (the group of scandium and the lanthanide series elements). There are 6 elements above the detection limit (Gadolinium, Neodymium, Praseodymium, Scandium, Samarium, Yttrium).
The Neodymium concentration is 2 times higher than the content of Gadolinium and Yttrium.
The Neodymium concentration is 4 times higher than the content of Praseodymium, Scandium and Samarium.
In the case of Dysprosium, Europium, Lutetium, Terbium, Ytterbium the concentrations were below 1 mg/kg. -
Examining the production parameters of European perch (Perca fluviatilis) juveniles under different lighting conditions
149-153Views:160European perch (Perca fluviatilis) is a native predatory fish in Hungary, and a promising new species of fresh water aquaculture nowadays. The European perch can be characterized by a high stress sensitivity during the intensive rearing, thus the optimization of environmental conditions has significant importance in the early life stages of fish. The aim of our study was to determine whether the light intensity and darkening of the water by humic acid affect the survival and growth performance of European perch juveniles. The experiment lasted for 28 days. Rectangular aquariums were arranged in 3 lines, the test environment consisted of 24 units. The experiment was set up with 10–10 fish per aquarium, total of 240 individuals. The average wet body weight of the fish at the start of the experiment was 1.69 grams. During the experiment, 6 treatments in 4 replicates were set up. In the first row, we set up 305.6±66.0 LUX (L), in the second row 118.0±24.4 LUX (C), and in the third row (D) 17.0±8.6 LUX illumination was set up. In each row the water of four aquariums were darkened by the addition of humic acid (H) (L, LH, C, CH, D, and DH). At the end of the experiment high survival rate was observed in all treatments. Examining the survival rate, the best results were found in the strongly illuminated treatments (L; LH- SR%=100±0.00). The observed mortality was caused by cannibalism. Regarding the individual body weight, the best results were shown by the treatments where the aquariums were illuminated with lower light intensity (C: 4.66±0.33 grams) and the aquarium water was darkened by humic acid (CH: 4.93±0.15 grams). The results of the C and CH groups were significantly better compared to the other treatments, however, they did not differ statistically from each other. The darkening of the water had a positive effect on the individual body weight of fish reared under full light (L: 3.73±0.28 grams; LH: 4.33±0.28 grams), whereas in the case of fish reared in the lowest illumination, the addition of humic acid did not affect the results (D: 3.78±0.15 grams; DH: 3.80±0.26 grams). In case of SGR (C: 3.64%/day and CH: 3.74%/day) and FCR (C: 0.84 g/g and CH: 0.78g/g) the best results were obtained by the C and CH treatments, also.
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Effect of arginine, putrescine and spermidine on the polyamine, proline and chlorophyll content of tobacco (Nicotiana tabacum L.)
39-43Views:117Polyamines, such as spermidine (Spd) spermine (Spm) and their direct precursor, the diamine putrescine (Put) are vital and essential aliphatic amines which are also present in plants. Although ethylene and polyamines are also involved in fruit ripening, the genes coding them must also take part in other biosynthetic pathways. In the ethylene and polyamines play an important role in development of salt stress tolerance, and in responses for biotic and abiotic stresses. Exogenous application of all three main polyamines (Put, Spd, Spm) increase salt tolerance of plants, but, accordingly to previous experiments, spermidine has the main effect on the enhancement of salt tolerance. Nicotiana tabacum L. plants were grown in vitro on MS medium, the treatments were as follows: arginine (150 mg l-1), putrescine (10 mg l-1), spermidine (10
mg l-1). Proline, chlorophyll a, b and polyamine contents were measured. The obtained results show that the arginine decarboxylase and the spermidine synthase genes involved in polyamine metabolism, cannot be enhanced by exogenous addition of their precursor molecules. On the contrary, the spermine synthase gene has a positive effect to the lower-class forms of polyamines.