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Effect of arsenic treatments on physiological parameters of sunflower and maize plants
81-84Views:755The environment is contaminated with heavy metals and other toxic compounds. One of the most important toxic element is the arsenic (As).
The objective of our study was to investigate the effect of As on fresh and dry weight of sunflower and maize in the early growth phases.
Seedlings were grown in climate room on nutrient solution which were treated with 3, 10 and 30 mg kg-1 arsenic. The plants were treated separately with As(III) and As(V). After 14 day, changes in fresh and dry weight of maize shoots and roots were recorded. In the case of sunflower these parameters were measured after 21 day.
The applied As(III) and As(V) decreased the fresh and dry mass of the shoots and roots of seedlings, especially at concentration 30 mg kg-1. We can draw the conclusion that the treatments of the maize and sunflower roots with arsenic had negative effects on the biomass accumulation. We found that the sunflower plants are more sensitive to arsenic toxicity than maize plants, and all data demonstrate that the As(III) is more toxic to these plants than the As(V).
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A partial botanical survey of a gamepreserve
27-30Views:524Hungary 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. -
Studies on the development of food attractants catching noctuid mouths (Lepidoptera: Noctuidae)
86-91Views:447The monitoring of the most dangerous noctuid pests (Lepidoptera: Noctuidae) can be performed by species specific pheromone traps. Recently the development of traps catching female moths became the main objective of the studies. We studied the synergistic effect of vine and beer as natural additive on the effectiveness of baits containing isoamyl alcohol and acetic acid in Forró and Debrecen-Ondód. The addition of vine and beer had positive effect on catches and it was significant in case of two dangerous pest species Agrotis segetum and Lacanobia oleracea. The synergistic effect was also significant with regard to the number of detected species especially in case of lower abundances and rare species.
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Comparative examination of the tillage systems of maize on meadow chernozem soil
21-24Views:489Maize production plays a major role in the agriculture of Hungary. Maize yields were very variable in Hungary in the last few decades. Unpredictable purchase prices, periodical overproduction, the increasing occurrence of weather extremities, the uncertain profit producing ability, the soil degradation processes (physical, chemical and biological degradation) and the high expenses are risk factors for producers. Due soil tillage, there is an opportunity to reduce these risks. Based on the experimental database of the Institute of Land Utilisation, Regional Development and Technology of the University of Debrecen, Centre for Agricultural and the KITE Plc., various cultivation systems were examined with maize (Zea mays L.) as indicator plant in Jász-Nagykun-Szolnok country in 2012 and 2013. The sample area can be found in the outskirts of Kenderes on a meadow chernozem soil. On the examined plot, strip-tillage, subsoiling and moldboard ploughing were performed, each on 4.5 ha, respectively.
In general, our findings show, that strip-tillage and subsoiling can be alternative tillage systems beside moldboard ploughing on meadow chernozem soils in Hungary.
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Elemental content of propolis samples from Pest, Zala and Bács-Kiskun county (Hungary)
149-153Views:571The elemental content of 61 raw propolis samples from Pest, Zala and Bács-Kiskun county (Hungary) were analyzed by ICP-OES. The content of Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr and Zn were measured in the samples. Median is higher than mean in all cases based on the summarized results. It can be explained by the outliers, moreover it has a non-normal distribution. The concentrations are in an extremely wide range, the ratio of the maximum and minimum is under 10 in case of six elements, between 10 and 35.1 in the case of other six elements,and more than 300 in case of Zn. Significant differences are between counties only in the case of B, K and P based on ANOVA. Other elements have no significant differences. The following order can be set up based on the mean concentrations and the wide ranges: K≥Ca>P≥S≥Fe≥Mg≥Al>Zn≥Na>Mn≥B>Cu≥Sr. Moreover it can be established, that the measured concentrations are near the same or in some cases lower than in other publications.
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Insect base-protein: A new opportunity in animal nutrition
129-138Views:988The consumption of insect protein, as well as its use in animal feeding, has become a trend. This trend is particularly receiving a lot of attention in animal nutrition because the current protein source of the highest quality in animal feeding which is fishmeal is unsustainable, expensive and its demand is higher than supply. Insect protein can be of great potential in combating world hunger as the world population continues to increase. The potential of insect protein is wide-ranging, it could improve the economics of feed production, lead to cleaner production due to its low environmental footprint.
This review focuses on the need, (nutritional and environmental) advantages of insect protein in feed production, as well as previous research findings.
The unanimous conclusion of the reviewed papers is that insect protein has a great potential in feed production in terms of nutritional value, environmental implication, sustainability as well as economic implication.
However, there is a need for the intensification of research on this alternative protein source in Europe, especially in aquaculture due to the approval of 7 insect species in aquafeeds by the European Union. Another reason for the intensification is that there is still much to be done as a result of past research which shows that growth effects vary based on species and inclusion level.
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The development of the scientific bases of horticulture and the history of horticultural innovation in the Northern Great Plain region and in Debrecen
17-20Views:239It can be told about the second half of the XXth century that, apart from preferring the large-scale growing of field plants and the largescale
livestock farming, corresponding to the central political will of the communist era, the significance and innovation output of
horticultural education in Debrecen was rather of follow-up trait, of secondary importance. The Tobacco Research Institute continued the
research work, and then even this activity was stopped. According to a survey finished in 1997, the mentioned institute had no invention,
granted patent, protection for registered model or any application for patent in progress at the Hungarian Patent Office. Until this time, invention activity at the University of Agricultural Sciences was of medium standard. In the National Patent Office, seven patent applications related to agricultural production and nine patent applications for other fields submitted under the inventors’ names were recorded. In the same period, the Cereal Research Institute (Szeged) led the absolute innovation list of Hungarian agricultural R+D institutions and university education institutes by submitting 164 own patent applications. Both in domestic and international terms, the horticultural innovation conducted at the University of Agricultural Sciences, despite the individual research results and achievements deserving recognition, without appropriate background – remained unnoticed. Let us put it this way: for the past decades, the light of the Debrecen Flower Carnival has not been thrown on the horticultural teachers and researchers of Debrecen. -
Agricultural relations of the increasing carbon dioxide emissions
197-201Views:745Emissions of carbon dioxide (CO2) have deserved more and more attention of humanity since decades, but inspite of theme asures already taken there are no substantial results. CO2 is a very important chemical, one of the greenhouse gases, which on the one hand offsets the cooling of the Earth, but on the other hand the too high CO2 emission leads to the global warming. The emission from the soil contributes substantially to the global cycle. This type of emission is influenced by the soil moisture, temperature, the soil quality and the cultivation. Through our measurements we have studied the relationships between the type of cultivation and the emissions of carbon dioxide.
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Analysis of sweet corn nutritional values using multivariate statistical methods
103-108Views:734Processing large amounts of data provided by automated analytical equipment requires carefulness. Most mathematical and statistical methods have strict application conditions. Most of these methods are based on eigenvalue calculations and require variables to be correlated in groups. If this condition is not met, the most popular multivariate methods cannot be used. The best procedure for such testing is the Kaiser-Meyer-Olkin test for Sampling Adequacy. Two databases were examined using the KMO test. One of them resulted from the sweet corn measured in the scone of the study, while the other from the 1979 book of János Sváb. For both databases, MSA (measures sampling adequacy) was well below the critical value, thus they are not suitable e.g. for principal component analysis. In both databases, the values of the partial correlation coefficients were much higher than Pearson’s correlation coefficients. Often the signs of partial coefficients did not match the signs of linear correlation coefficients. One of the main reasons for this is that the correlation between the variables is non-linear. Another reason is that control variables have a non-linear effect on a given variable. In such cases, classical methods should be disregarded and expert models better suited to the problem should be chosen in order to analyse the correlation system.
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The Effect of Grazing Intensities on Magnesium Contents
8-13Views:899Research 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. -
Effect of Selenium Supplementation on in vitro Radish and Green Pepper Seedlings Germination
149-155Views:708Selenium (Se) is an essential trace element for animals, microorganisms and some other eukaryotes. It has become increasingly evident that Se plays a significant role in reducing the incidence of lung, colorectal and prostate cancer in humans. Although there is evidence that selenium is needed for the growth of algae, the question of essentiality of Se in vascular plants is unresolved. Therefore Raphanus sativus (Se accumulator) and Capsicum annuum (non Se accumulator) were treated with 0-200 mg/l natrium-selenate. The results showed that lower (2 mg/l) concentration natrium-selenate increased the fitomass and total antioxodant capacity in seedlings.
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Heat stress of cattle from embryonic phase until culling
11-22Views:813Heat stress becomes a serious problem in the livestock sector as it affects cows' performance negatively. The objective of this paper review is to investigate the effects of heat stress during the different phases of the life cycle of cows; embryos, calves, heifers, and cows. Heat stress during early maternal gestation affects the ability of embryos to develop increasing the risk of abortion and early embryonic death. Heat stress during late maternal gestation affects the performance of calves and heifers later in their life, as it reduces growth performance, conducts physiological changes, impaired immunity, changes the behavior, and reduces the length and intensity of the estrus in heifers with decreasing in milk production in the first lactation. On the level of cows, milk quality and production, meat quality, and the final body weight decrease under hot temperatures. Heat stress decreases the conception rate, alters follicle growth, and estrous symptoms. Hormones secretion and physiological changes because of the heat stress conduct to impair the immunity system, and in oxidative stress and death in some cases. Same as for calves and heifers a change in the behavior of cows was detected in order to decrease their temperature.
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The impact of employment and income circumstances on the development of regions
15-19Views:652The economic condition of an area is fundamentally determined by the extent of employement, as well as the size and composition of its active population. No sustainable economic growth is possible without the necessary amount of employees with the proper skills.
As regards the proportion of employees, i.e. economically active people is significanlty lower in Hungary than not only in Western Europe, but also countries which joined the EU recently. One of the reasons for this fact is the low amount of part-time employment and the other is the phenomenon that the number of agricultural employees – who had a significant role – greatly decreased in the county.
The employment level of the population in the county is nearly identical as that of the North Great Plain region and it is lower than the country average. The activity proportion, i.e. the joint proportion of employees and unemployed people in the population between 15–74 years of age is 3 percentages lower than the country average. The proportion of unemployed people greatly varies depending on the small regions of the county. The proportion of registered unemployed people in the population of active age is the lowest in Debrecen and the highest in the Hajdúhadház small region. The unemployment of career-starters is a further problem to deal with.
The composition of employees in the county is different than the country average. When compared in terms of different economic sectors, it can be observed that agriculture, game management, forestry and fishery are more significant than the country average. Of the provider sectors, the proportion of financial activity, real estate matters and economic services is lower, while that of accommodation services and hospitality is higher than the country average.
There are regional differences similar to unemployment in terms of the income size which is the basis of personal income tax per taxpayer.
The income level in the North Great Plain region is lower than the country average mainly in terms of income paid for work, where this difference is 23%, while it is only 5% in the case of social income. Altogether, the income and expenditure data of the North Great Plain region are not favourable. -
The effect of genotype and the location of sampling on the mineral content of wool
157-160Views:797Mineral supplementation is very important in high producing farm animals. The estimation of exact mineral intake is very difficult in forage eating animals, like sheep. Accessing of long term mineral status seems to be possible using wool mineral analysis. However several factors can affect the results. Therefore, the aim of this study was to test the effect of breed and sampling location on the mineral content of sheep wool. 20 Dorper and 20 Tsigai sheep were chosen from the same farm. Samples were obtained from 3 locations (withers, side and quarter) and tested for 8 elements: Ca, Mg, Na, Co, Cu, P, S, Se , Zn. The samples were cleaned with ethyl alcohol from organic contamination, then after adding nitric acid were mineral analized using ultrasonic cleaning unit. The samples were analysed with ICP-OES (Perkin-Elmer, Optima 3300 DV). Statistical analyses were carried out by GLM procedure of SAS statistical analyses software. Differences between means were checked with Tukey-test. Significant breed differences were detected in the case of Mg, Na, S, Se in spite of the same feeding regime. The wool mineral content were within the reference range. The sampling location had no effect on the mineral content of wool.
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The effect of sowing date and plant density on the yield of maize (Zea mays L.) under different weather conditions
205-208Views:708Maize has high productivity and produces huge vegetative and generative phytomass, but this crop is very sensitive to agroecological (mainly to climatic, partly to pedological conditions) and agrotechnical circumstances. In Hungary, maize is grown on 1.1–1.2 million hectares, the national average yields vary between 4–7 t ha-1 depending on the year and the intensity of production technology. The longterm experiment was set up in 2015–2016 on chernozem soil in the Hajdúság (eastern Hungary). The maize research was set up on chernozem soil at the Látókép MÉK (Faculty of Agricultural and Food Sciences and Environmental Management) research area of the University of Debrecen. We examined the following commonly used hybrids of Hungary: SY ARIOSO (FAO 300), P9074 (FAO 310), P9486 (FAO 360), SY Octavius (FAO 400), GK Kenéz (FAO 410), DKC 4943 (FAO 410). The experiment was set up in three different plant densities. These were 60, 76, 90 thousand plant ha-1. The experiment was set up with three different sowing dates, early, average and late sowing. The yield was measured using a special plot harvester (Sampo Rosenlew 2010), measuring the weight of the harvested plot and also taking a sample from it. As a next step, we calculated the yield (t ha-1) of each plot at 14% of moisture content to compare them to each other. We evaluated the obtained data using Microsoft Excel 2015.
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Molecular Biological Approach of Crocus sativus L. and its Allies
112-115Views:685The hay saffron (Crocus sativus L.) is a sterile triploid plant, known in human culture only, with no fertile seeds produced. The origin of saffron is still a mist, however it is assumed to be an autopoliploid mutant or a hybrid. The recent classification and most of the former taxonomic publications define C. sativus to be derived from C. cartwrightianus, a wild species. Because of the sterility of hay saffron it seemed to be reasonable to apply molecular biological methods to complete classical taxonomic studies in examining its relations. The DNA polymorphism based AFLP method has confirmed the close relationship between these species.
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The composition of gluten proteins and their effect on the rheological properties of gluten
124-129Views:618Wheat is the major cereal component of bread in the world and is grown worldwide. Of the cereals only the bread wheats – and less the triticale – includes storage proteins that play an important role in the performance of gluten. Proteins of gluten complex may be present in two classes:
− low molecular weight (gliadin-) components, and
− high molecular weight (glutenin-) components.
Gliadins shown appreciable heterogenity and can be separated into 40-50 components with gel electrophoresis. The composition of gliadins is employable for the identification the wheat varieties and to investigate the varieties. In the decreasing electrophoretic mobility sequence may be distinguish α-, β-, γ- and ω-gliadins. A glutenin subunits may be include in two classes:
− high molecular weight glutenin subunits (HMW-GS),
− low molecular weight glutenin subunits (LMW-GS).
Wheat varieties can be identified by glutenin and their quality selection is also possible. The gliadin’s polypeptides encoding genes are located on the short arm of chromosomes 1A, 1B and 1D, 6A, 6B and 6D. Genetic coding for HMW subunits is located on the long arms of chromosomes 1A, 1B and 1D, the LMW-GS are also located on chromosomes 1A, 1B and 1D (Glu-3 loci) near the gliadin-coding loci.
Storage proteins affect the rheological properties of gluten by two factors:
1. The quality and quantity of the protein components of the gluten complex,
2. The interactions between the protein fractions. -
The effect of reduced sprinkler programs on the main fungal pathogens of apple in environmentally sound production systems
13-16Views:331Aim of our two-year study was to evaluate the possibilities of chemical use against key fungal pathogens (apple scab, apple powdery mildew and brown rot) in integrated and organic apple production. Therefore, first, disease incidence was compared in standard and reduced spray programmes and then each technological variation was evaluated from practical point of view. Altogether four spray programmes were compared. Standard and reduced spray programmes were performed in the integrated production. The same pesticides were used in the reduced spray
programme compared to standard one but numbers of spray were reduced by 25% at the second half of the season. Standard and reduced spray programmes were also performed in the organic production and the numbers of spray were reduced by 40% in the reduced spray programme. Incidence of diseases was low in both standard and reduced spray programmes in integrated production. Diseases level was high in the organic production and disease increased significantly in the reduced spray programmes compared to standard programmes. Results showed that reduction in spray numbers at the second half of the season can be used practically in integrated production. Omission of sprays in organic
production resulted in serious disease management risk; therefore, it is not recommended for practical use. -
Regional economic achievements and reindustrialisation in Hajdú-Bihar county
65-74Views:742The North Great Plain region is one of the backward regions of Hungary. The low level of economic development is mainly due to the lack of industrial development. The region is poor in natural resources, its main resources are land, natural gas fields, carbon dioxide, thermal water and the clay mineral stock.
The structure of GDP per capita of the county is different than the country average mainly because of the high proportion of agriculture.
The proportion of the industry and the building industry is not significant. Of the various service provider sectors, trade, transport and telecommunications have a small proportion, while financial and economic service providers have even lower share, which is due to the fact that these sectors are mostly concentrated in Budapest. The share of public and human service prodivers is higher than average due to the University of Debrecen.
The GDP which expresses the economic development of the county in a complex way increased four times its previous value in nominal value between 1995–2009. However, if the real value is considered, the increase is less than 25%, as opposed to the country average, which was less than 40%.
The most complex index of the development level of an economy is GDP expressed either in nominal or real value. If expressed in dollars, GDP is suitable for international comparison with the correction based on the purchasing power parity per person.
The county represents 4.3% of the people employed in the industrial sector in Hungary, while its share in industrial production is only 3.3% which is lower than the regional and population share of the county within Hungary. As regards industrial production per person, Hajdú-Bihar was the 10th county in Hungary; therefore, it is considered to be a less industrialised county.
The product structure of GDP is suitable for drawing useful development conclusions, but the result is more reliable if the income creation ability is also analysed on the basis of the employment structure. -
The olive (Olea europaea) and the almond (Prunus amygdalus) related phytonutrients, and the associated health-promoting biological effects, a review
11-24Views:482With the increasing attention to the health promoting activities of the bioactive compounds from some plants, many researchers are focusing on the biological potential and mechanisms of certain cultivated plant species. In this review, we survey the olive and almond based extracts specific phytoconstituents and their associated health promoting effects that have been evaluated in experimental and clinical studies.
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Characterisation of basic water balance parameters of Debrecen
35-40Views:709This work aims to develop a hydrological modelling tool to help managers make the right decisions for Debrecen, in the face of water scarcity and the increase in agricultural and domestic needs over time. The methodology was based on the creation of a climatic database, at monthly time steps, from 2016 to 2019, and cartographic (land use, digital elevation model, and hydrological network). As a next step, the watershed was delimitated into sub-basins to determine the shape and the physiographic characteristics of sub-watersheds. Finally, a hydrological study was prepared by calculating the time of concentration to build a database of water resources in the study area. This water resource will be used as an input parameter for urban farming.
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Rheological evaluation of industrial tomato
137-140Views:334Today, tomato has the second largest harvesting area globally, and the fourth largest in Hungary. The importance of industrial tomato is growing year by year, and one of the most important tasks is to satisfy the needs of the industry. To meet these needs, the producer has to find the proper genotype, which can achieve up to 100 t ha-1 crop yield. This quality has high importance to be researched.
The experiment was carried out in the Botanical and Exhibition Garden of the University of Debrecen, with 3 examined genotypes. The planting date was 3 of May 2018. The harvesting was two-threaded. On 27 of July the physical parameters – fruit shape index (length/diameter), firmness (kg cm-2), water-soluble dry matter content (Brix%) and weight of the berries (g) – were evaluated. On 15 of August the rheological parameters were examined – the force needed to tear the skin – bioyield point (g) and flesh firmness (g).
The fruit shape index was oval (between 1.19 and 1.24) for all the examined genotypes. The firmness was between 0.92 (UG1122713 F1) and 1.05(Prestomech F1) kg cm-2, which compliance the needs of the industry. The water-soluble dry matter content was suitable, with a value between 4.49 (Prestomech F1) and 4.65 (UG1122713 F1) Brix%. The weight of the berries was between 45.94 (UG989 F1) and 49.37 (Prestomech F1) g per piece.
The bioyield point was between 76.00 (UG1122713 F1) and 85.16 (UG989 F1) g. The flesh firmness was between 33.68 (UG1122713 F1) and 42.81 (UG989 F1) g.
Finally, we can conclude based on the obtained data that the UG989 F1 hybrid was the most proper for the applied cultivation conditions. This genotype can be recommended for the farmers even in extreme weather conditions.
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Studies of Cryphonectria parasitica (MURR.) BARR subpopulations on Quercus petraea in Ukraine
70-75Views:446Chryphonectria parasitica (Murr.) Barr, the casual agent of chestnut blight disease, which is one of the most important fungal pathogens of chestnut (Castanea sativa). The disease seriously affected the chestnut in Northern-America and in Europe as well. It is important to mention that the pathogen does not only infect the chestnut but oak species (Quercus spp.) also. In the Carpathian-Basin, the chestnut is endemic in the Mecsek mountains, in Zala, in Somogy counties but it also can be found in the Danube-Bend. In the Carpathian-Basin (outside Hungary) the chestnut is found in Slovakia, Ukraine, Romania. In our study bark samples infected by Cryphonectria parasitica were collected from Bobovyshche, Serednje and Rostovjatica (Ukraine). The rate of infected chestnut tree were higher than 90% around Bobovyshche and beside chestnut, the symptoms were detected on oak trees as well. We collected bark samples from chestnut and oak as well and then we isolated the pathogen Cryphonectria parasitica in the lab of University of Debrecen. Symptomatological observations, laboratory examinations on fungus morphology, as well as comparisons of ITS sequency homology were made and approved that the causal agent of new disease was Cryphonectria parasitica. Our results proved that the Cryphonectria. parasitica infects oak trees beside chestnut in the Carpathian-Basin. Further studies are needed to determine the VCG (Vegatative Compatibility Group) group of the Cryphonectria parasitica found on oak trees.
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Effects of soil compost application on the leaf surface area per running meter of apple (Malus domesticaBorkh.) leaves cultivated in organic and integrated orchard
111-116Views:426The effect of different compost doses on the nutrient contents of the soil (in depth of 0–30) were measured in an (organic and integrated) apple orchards. The leaf surface area per running meter shoot for certain apple species (Golden Delicious and Pinova) were determined.
The field experiments were conducted in the Research Field of Debrecen-Pallag, University of Debrecen, the analysis of the soil and plant samples took place in the laboratories of the Institute of Agricultural Chemistry and Soil Science.
The compost treatments increased the amount of the examined nutrients in the top 30 cm of soil originated from organic and integrated orchard. Changes in rainfall were observed in the trends of the leaf surface area of the two apple varieties. 2010 was rainy and 2012 was drier. The leaf surface area of the Pinova increased better under the precipitation/year effect, than in case of the nutrient supply treatments. The opposite was observed in case of the Golden Delicious. -
Use of essential trace elements enriched Artemia in the larval rearing of barramundi (Lates calcarifer)
11-16Views:477Artemia is a vital nutriment in the rearing of barramundi (Lates carcarifer), however it’s mineral trace element content does not cover the requirements of the larvae. In our experiment the assumption was wether the cobalt, zinc and manganese concentration of Artemia could be increased during a 24 hours of enrichment period, as well as we wanted to investigate the resulted interactions between the elements. For this purpose 50, 100 and 1000 mg l-1 cobalt-chloride treatements (Co50, Co100, Co1000) were applied while in the case of 50 and 100 mg l-1 treatments the enrichment was also complemented with zink-sulphate and manganese-chloride in the same concentrations. According to the results the zooplankton were able to accumulate cobalt in higher amount, and yet zinc and manganese had no significant effect on each other, a strong synergistic effect occurred between cobalt and manganese. After the enrichment period the impact of essential trace element supplemented live feed on the survival and growth of barramundi larvae was also studied. The experiment was carried out by using 15 days-old larvae applying a total of 9 treatments for two weeks (Control, Co50, Co100, Mn50, Mn100, CoZn50, CoZn100, CoMn50, CoMn100), in duplicates. Considering the per cent of survivals, no significant difference was observed between the treatements (P>0.05). In the case of CoMn50 and CoMn100, the loss statistically increased (P<0.05) compared to the Control (80.5±4.95%) group. Our results show, that the Mn100 and CoMn100 treatements resulted in ignificantly higher (P<0.05 ) in divid ual bod y w eight s, how ever taki ng the survival also into consideration the Mn100 treatements proved to be the most
effective.