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  • Soil moisture sensors for sustainable water management in field crop production: A review of advances and application challenges
    41-54
    Views:
    447

    Efficient water management is essential for sustainable production of field crops amid climate change, population growth, and water scarcity. Traditional irrigation practices often lead to water use inefficiency, which harms soil health and reduces yields. To address this, reviewing previous studies on soil moisture sensors provides important context and guidance. Literature from Scopus, Google Scholar, and WoS (2019–2025) on soil moisture sensors for sustainable water management in field crops was screened. Out of 244 retrieved publications, 79 met the inclusion criteria with a focus on sensor technologies, applications, advances, and challenges, analysed thematically for research gaps and insights. Based on the findings, soil moisture sensors boost water management, improve yields of field crops, and support sustainable agriculture. However, hindrances related to high costs, lack of awareness, technical complexity, calibration needs, energy challenges, data interpretation difficulties, and compatibility problems hinder effective soil moisture sensor results. Integrating soil moisture sensors with decision-support tools optimises water use and protects soil health to promote long-term productivity under climate variability. Future research should strategise on the development of low-cost, reliable soil moisture sensors with technology subsidies, training, policy support, durability, integration, and simple data to empower farmers to adopt precision water management.

  • The potential use of Pediococcus spp. probiotic in aquaculture: A review
    99-106
    Views:
    613

    Aquaculture production has significantly increased over the previous few decades. However, antibiotics have been implemented regularly and extensively to overcome outbreaks of pathogens in aquaculture to cover the human needs for animal protein, leading to the appearance of resistant strains that may cause serious damages in the environment and also human health. In the last few years, the implementation of probiotics as an alternative technique to antibiotics use in fish production has achieved promising results in aquaculture due to their beneficial impact on fish health and growth performance. Among different types of probiotics, the Pediococcus spp. bacteria stand out as a promising probiotic for their beneficial impact to aquaculture. Thus, the current study has been conducted to give an overview about the interactions between Pediococcus spp. and aquaculture. In addition, this review highlights the role of Pediococcus spp in promoting growth performance, improving feed conversion ratios and the intestinal architecture, enhancing the immune response and inhibiting fish pathogens, thereby preventing or at least reducing the use of antibiotics. Practical use of Pediococcus spp. probiotic in aquaculture as feed additives through selected case studies is also considered.

     

  • Food safety of plant origin food
    161-164
    Views:
    478

    Expectation regarding changes related to food production, transportation, distribution and marketing have changed considerably in several regions of the world over the past decades. It is especially true for highly industrialized countries where not only the food security is important but the food safety is essential too. The concentration of production – processing – distribution involves the danger on the one hand products of unsuitable quality from point of view of nutritional physiology and the other hand ones that may contain substances harmful to human health will become widespread among consumers. We investigated the heavy metal, pesticide remains and mycotoxin content of different plant products.

  • Economics of site specific crop density in precision sunflower (Helianthus annuus L.) production
    91-96
    Views:
    462

    In this research, the crop density of sunflower was examined, which, thanks to the tools available for precision crop production and knowledge of the market environment of sunflower production, best fits the heterogeneous areas of the given production zones and meets the economic requirements. These components together directly influence the effectiveness of sunflower production. In the year of 2021 and 2022, we carried out a site-specific crop density sunflower experiment in two fields with the same soil type, by sowing significantly different amounts of seeds within the given zones. We have established that the sunflower, although a plant with excellent adaptability, reacts sensitively to the place of production and the effect of the year, in zones with heterogeneous productivity, and shows a reaction to sowing with a variable number of seeds per zone, even when examined based on economic aspects.

  • Milestones in the development of agronomic management practices in crop production
    203-209
    Views:
    284

    From the dawn of the history of the human race, agriculture has always been a profound activity of mankind producing food and feed as well as various plant originated materials for further processing.

    Agronomy, like any other human activity, depends on the perpetual development of knowledge and technical skills, - in a modern context – science and innovation. This paper is intended to provide the reader with information regarding the main phases of the development of agricultural production from the Neolithic societies through the early Mesopotamian and Egyptian empires to the inventions of first organised learned society of Rome. The major research findings of the past two millennia including agro-chemistry, genetics and technical development are presented.

    Such a review should not lead to any scientific conclusions, but rather a philosophical postulate similar to that of Jonathan Swift written some centuries ago: “And he gave it for his opinion, that whoever could make two ears of corn, or two blades of grass, to grow upon a spot of ground, where only one grew before, would deserve better of mankind, and do more essential service to his country, than the whole race of politicians put together”.

  • The current status, challenges and prospects of native pig production and large-scale farming in Laos
    155-161
    Views:
    801

    This review aimed to investigate the potential native pig development and the trend that large-scale farming may influence native pig production in Laos. The review found that native pigs were estimated to be around 88% of the total pig population in Laos in 2023. Commercial pig farming was found only in the main cities, particularly the central and southern provinces, which increased from 578 in 2019 to 703 farms in 2022 and 737 farms in 2023. Due to the serious economic crisis starting in 2021, many Lao pig producers stopped their businesses, leading to the decline of the commercial pig population by almost 30% in 2023 compared to 2022. The average pork per capita consumption in Laos in 2021 was estimated at about 14.2 kg. Though not as high as the backyard, commercial farms still contribute essentially to the pork supply in Laos (12%), increasing the volume from 87,628 tonnes in 2015 to 137,775 tonnes in 2024. The main native pig producers are small-scale rural farmers who have not yet improved productivity or reproductive performance, and the main purpose of their production is household consumption rather than market orientation. However, farmers, mainly in the main cities, improved them by cross-breeding native pig sows with Duroc boar for better lean meat. The main challenges for native production in Laos include poor farm setup and management, high cost of commercial feed, and poor breeding and genetic management. Therefore, creating awareness of the benefits of setting up a pig farm and management, providing better option strategies for utilising locally available feeds, and providing better strategies on pig breeding could improve native pig production in Laos.

     

  • The scientific background of competitive maize production
    33-46
    Views:
    1066

    The effect and interaction of crop production factors on maize yield has been examined for nearly 40 years at the Látókép Experiment Site of the University of Debrecen in a long-term field experiment that is unique and acknowledged in Europe. The research aim is to evaluate the effect of fertilisation, tillage, genotype, sowing, plant density, crop protection and irrigation. The analysis of the database of the examined period makes it possible to evaluate maize yield, as well as the effect of crop production factors and crop year, as well as the interaction between these factors.

    Based on the different tillage methods, it can be concluded that autumn ploughing provides the highest yield, but its effect significantly differed in irrigated and non-irrigated treatments. The periodical application of strip tillage is justified in areas with favourable soil conditions and free from compated layers (e.g. strip – strip – ploughing – loosening). Under conditions prone to drought, but especially in several consecutive years, a plant density of 70–80 thousand crops per hectare should be used in the case of favourable precipitation supply, but 60 thousand crops per hectare should not be exceeded in dry crop years. The yield increasing effect of fertilisation is significant both under non-irrigated and irrigated conditions, but it is much more moderate in the non-irrigated treatment.

    Selecting the optimum sowing date is of key importance from the aspect of maize yield, especially in dry crop years. Irrigation is not enough in itself without intensive nutrient management, since it may lead to yield decrease.

    The results of research, development and innovation, which are based on the performed long-term field experiment, contribute to the production technological methods which provide an opportunity to use sowing seeds, fertilisers and pesticides in a regionally tailored and differentiated way, adapted to the specific needs of the given plot, as well as to plan each operation and to implement precision maize production.

  • Preliminary results on Siberian sterlet (Acipenser ruthenus marsiglii) fries rearing under intensive conditions
    27-31
    Views:
    244

    In our experiments production performances of Siberian sterlet were tested under intensive tank conditions. During the 25 days long experiment effectiveness of weaning to artificial diet of the fish was investigated. Production performances of fish fed on exclusively dry diet from the beginnings were lower than the other two groups. Between the values of sterlets fed on live food also then suddenly vs. continuously were weaned to dry diet there were no significant differences. Based on our results live food feeding could be suggested for the Siberian sterlet larvae for some days but the method of the weaning to dry diet has no significant influence to the production performances.

    In 21 days long experiment four different feeding frequencies were tested in Siberian sterlet (~13 g) fingerlings. Dry feed was offered for the fish continuously, 2, 3 and 4 times per day. There were no significant differences between the values of the four treatments. Based on our results there is no high influence of feeding frequency in case of this size group of Siberian sterlet.

    During the nursing in two different size groups of Siberian sterlet the optimal daily amounts of feed were aimed to determine. In case of growth values of the group fed at 7% of the total biomass were higher than the other two groups (3 and 5%). Feeding performances of fish fed at 5% were significantly better than fish fed at 7%. Based on our results for ~20 g size of the subspecies at least 5% of total body weight could be suggested.

    In case of ~150 g size of the fish the production performances of fish fed at 1% were lower than the other two groups (2 and 3%). Between the values of stocks fed at 2 and 3% there were no significant differences. Based on these results 2% of total body weight of dry feed could be suggested for the Siberian sterlet with ~150 g body weight.

  • The effect of silver crucian carp (Carassius auratus gibelio Bloch) on the yields and the production value of common carp (Cyprius carpio) fingerlings
    5-10
    Views:
    409

    During the last few years, the spread of the silver crucian carp has caused significant problems in pond fish culture. One of the main challenges of successful fish production in fishponds, is to rid ponds of the silver crucian carp. The nature of the damage caused by silver crucian carp is a complex question. To get into the ponds, the crucian carps occupy the territory before the common carp, and competes for food with common carp. The silver crucian carp has a less favorable food coefficient than the common carp, and it’s value is also lower. Therefore, the income of the fish farm decreases. In the course of the experiment, carp fry were stocked in 5 nursing ponds at the same stocking rate, with different (0,- 50-, 100-, 150-, 200%) stocking rates of silver crucian carp fry, respectively. At the end of the experiment, the yield/hectar and the production values were calculated. The experiment proved that the presence of the silver crucian carp in the fishponds causes lower yields and production values.

  • Some basic problems concerning world animal production at the beginning of the XXI century
    77-80
    Views:
    226

    The author summarizes the main new challenges facing animal agriculture: growing GDP in many countries increasing animal protein demand, bioenergy industry as a new player using potential food or feedstuffs, increasing demand, Growing water and land scarcity, weaking the position of plant agriculture, feed production. Forecasts are summarized regarding the magnitude of meat consumption increases, and the possible plant biomass quantities required additionally in the next 20 years to cover the needs of food, feed and biofuel on a global scale.
    Efficiencies of various animal production sectors, poultry, pork, beef, mutton meat, milk and eggs and their environmental footprints are compared, summarizing the most important research  results concerning UK, USA, OECD evaluations. Intensive systems using highly productive plant and animal population will play an even more important role in the future especially in poultry, pig, milk and aquaculture production system being efficient users of resources (feed, water, land) and the environmental foot print is smaller per unit product.

  • An overview of swine production and marketing in Africa - Mini review
    121-129
    Views:
    609

     Pigs are the oldest domesticated animals, though their ancestry is still uncertain because of a lack of archaeological and genetic evidence. Pigs serve a vital role in reducing the demand for livestock and livestock products in most parts of the world. Especially in the African continent, pigs serve as mobile cash implying how easily they can be converted into cash to sort pressing family needs. Pig production in Africa is different from advanced systems of production in temperate countries, however, it has similarities with most of the tropical low and middle-income nations. Pig production in Africa requires attention to enable it to contribute effectively to the growing African population. However, it has been orchestrated with a myriad of challenges including market access. This mini-review is designed in a manner to provide an overview of pig production contribution to livelihoods in Africa and associated challenges with possible appropriate solutions.

  • The role of animal breeding with special regard to native pigs of food supply and rural development in Laos
    149-154
    Views:
    437

    The present paper explored the influence of breeding native pigs on livelihood conditions and the contribution of native pigs to the rural development and rural poverty reduction in the rural areas of Lao PDR. Pig production plays an important role in meat supply for both urban and rural areas of Laos. It is clear that most of the pig products in the country come from smallholder pig farms, and more than 90 percent of those products are the native pigs mostly raised by farmers in remote areas. In general, livestock production distributed between 15–18 percent to GDP, while most of animal production still remains as the traditional methods. Rural development is always the first priority of the Laos government since its independence in 1975, however, the poverty rate in rural areas remained high at 23% in 2018. It might block the development goal of the government which will lead the country out of the least development status by 2020. The food security and malnutrition in the rural or mountainous areas are considered as the majority issue that both government and several international organizations have been thriving hard to overcome, which researchers showed that more than 45% of children under 5 years of age were stunted, and 28% of them were underweight. Inspired of more than 50 % of the households in the rural areas of Laos reported they consumed chicken and pork at least one day a week. While native pigs play an important role on meat supply, it also constituted around 9–14 % of annual income of the households in rural areas. Therefore, the increase the production of pigs and poultry is one option to promote the meat supply to households in the rural areas of Laos. This paper will be a pathway to guide and identify for the final decision to what experiment will be implemented on Lao native pig in Laos (2021–2023) to complete the comparative study on reproductive physiology and reproductive management methods of Hungarian and Lao Indigenous pig breed. Which found it still needs further afford to research and improve more about native pig performance for all areas of productive and quality management.

  • The importance of chickpea (Cicer arietinum L.) and its cultivation in Hungary: A review
    71-75
    Views:
    269

    Climate change today is no longer a question for the future. Climate change impacts not only human populations but also plant species, which are increasingly exposed to its negative effects. The increasing number of days of drought, the lack of precipitation and its unfavorable distribution are observed each year, which require adaptation. Chickpea (Cicer arietinum L.) is a drought-tolerant species characterized by deep root system that enables it to withstand prolonged periods without precipitation. Additionally, it is a thermophilic crop and tolerates moderate increases in average temperature." There is no great tradition of its cultivation and use in Hungary, but it has been cultivated by the Iregszemcse Research Institute since the 1970s. In addition to the positive aspects of its cultivation, it also has good nutritional values, outperforming in some parameters the beans (Phaseolus vulgaris L.) and peas (Pisum sativum L.) what are popular in Hungary. Its high protein and crude fibre content allows it to be used not only for human consumption but also for animal feed. The aim of this review is to describe the importance of chickpea and to identify the advantages and disadvantages of its cultivation.

  • Comparison of supplier quality assurance methods for compound feed manufacturing from efficiency, product consistency and economical point of view
    29-34
    Views:
    234

    Feed manufacturing and human food production are the main routes of use for agricultural products. The food industryparticularly has intensively implemented the recent quality management principles and developed systems that facilitate the continuous improvement and efficiency of the industrial production. Feed production has taken similar approaches however the intensity of deployment at the manufacturer and the rollout towards its supply chain has shown slower progress. The methods, that the feed manufacturer manages the supplier chain of mainly primer agricultural products according to, have a certain impact on the efficiency of the inbound operations, feed product quality and its consistency as well as on other resources. These methods have been built on sound quality management principles that are stated not only in quality standards but also in relevant regulations. Current study addresses the questions related to the link between supply chain quality management and feed product. The objective of the frontier research was to highlight the  theoretical possibilities and benefits of the robust design methodimplemented into animal feed manufacturing dealing with highly variable ingredients. 

  • Changing of some parameters of the soil-plant system as an effect of different composts
    262-266
    Views:
    402

    Composting is an alternative way for practicing site-specific and environmental friendly plant nutrient supply. Our aim was to study the effect of different composts on plant and soil system. 
    Pot experiment with acidic sandy soil blended with three composts in five (0%, 5%, 10%, 25% and 50%) proportion was set up. Our experimental plant was perennial ryegrass (Lolium perenne L.). After the harvest of ryegrass we measured the fresh and dry weight of harvested plants, the P-, K-, Mg-contents, and the pH of soils.
    The three composts had different effect on dry weight production and on nutrient-supply of soil. We established that one of the compost had significantly larger effect on the dry weight of ryegrass compared to the others. In this study we proved that favourable compost/soil proportion is different in the case of different composts.

  • The use of Common duckweed (Lemna minor) as a biological filter in the rearing of hybrid African catfish (Clarias gariepinus x Heterobranchus longifilis)
    107-112
    Views:
    617

    The African catfish (Clarias gariepinus x Heterobranchus longifilis) is one of the most important fish species in Hungarian aquaculture. The larvae and juveniles are reared at high feeding rates, which can reach up to 10% of the biomass. Intensive feeding results in large amounts of effluent water, directly proportional to the intensity of fish production. The aim of this experiment was to investigate the potential of Common duckweed (Lemna minor) as a biological filter and its nutrient removal capacity during intensive fry rearing of the hybrid African catfish. In a recent study, two experimental recirculation systems, identical in water volume and design, were set up, in one of which duckweed was grown under aquaponic conditions, where the concentrations of nitrogen and phosphorus forms were monitored and the production parameters of the fish were determined. The results obtained from the experiment showed that the use of duckweed as a biological filter improves the water quality of the recirculation system. A significant amount of plant biomass was produced, which mainly reduced the nitrate and orthophosphate concentrations in the system water. As a consequence, the survival of hybrid catfish was improved, which also affected biomass growth, but had no effect on other parameters.

  • Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
    121-126
    Views:
    221

    Pesticides play a key role in fighting weeds, pests and parasitic fungi. According to surveys, pests reduce the yield of agricultural crops by 35% worldwide. Pests, fungi and weeds account for 14%, 12% and 9% yield loss, respectively (Gáborjányi et al., 1995). Chemicals have contributed to increasing and maintaining the yields of crop production for decades. Today, agricultural production (in spite of many efforts) is unthinkable without the use of pesticides (herbicides, insecticides and fungicides). On the other hand, these chemicals contribute to the pollution of the atmosphere, surface and underground waters, and agricultural soils, especially if they are applied improperly.
    The sustainable agricultural production pays attention to environment-friendly cultivation-technologies; but at the same time it makes an effort to produce good quality and economical products. The examination of the herbicides’ secondary effects, fits into this chain of idas namely, how the herbicides affect – stimulating or inhibiting – the soil microbiological processes, prevention of soil fertility.
    In the course of the experimental work the effect of herbicides on soil biological properties were examined in different maize (Zea mays) cultures. We wanted wished to know that how the herbicides affect the quantity change of soil microorganisms, the life of different physiological groups of bacteria and the activity of microorganisms. A small pot experiment was set up in 2008 with the application of two herbicides - Acenit A 880 EC and Merlin 480 SC – in the breeding house of the Department. The moisture content and nutrient supply were at optimal level in the experiment.
    On the basis of results the following can be stated: 
    1. It can be stated that the two herbicides and all their doses affected negatively the number of total soil bacteria, the
    inhibiting effects were significant. The quantity of microscopical fungi increased by the effect of Merlin 480 SC and decreased in the treatments of Acenit A 880 EC.
    2. The Acenit A 880 EC had stimulating effect on the nitrate mobilization. The CO2-production was stimulated by the basic doses of herbicides; the other treatments did not influence the CO2-production significantly.
    3. The quantity of microbial biomass-carbon –except for only one treatment- decreased significantly by the effect of herbicides. Besides it, the quantity of microbial biomass-nitrogen increased significantly in the treatments of Acenit A 880 EC.
    4. The biomass of test plant decreased in the treatments of herbicides, their quantities were smaller than in the control. In the pots treated by Merlin 480 SC, parallel with the increase of doses decreased the quantity of plant-biomass.

  • Land use, water management
    81-87
    Views:
    610

    Due to the prognosed population increase to 9.2 billion people by 2050, the world’s crop production does not have any other chance than to increase production. This demand is a huge challenge for agriculture. Based on the forecasts, the growth rate of production of the main cereals will decrease as a result of the effect of soil, water, the increasing fuel and fertiliser prices and the impacts of climate change. Methods ensuring sustainability have to be preferred. Precision agriculture is the most effective method of crop production. We have to apply minimum cultivation in order to protect the soil surface, maintain its moisture content and increase its water reception ability. In addition to the localised use of fertiliser, sowing seed, irrigation and pesticides, it is also important to apply them in a targeted way on the basis of plot imaging. The use of the new technology results in significant cost saving and it could also reduce environmental load.

  • Effects of the development of production factors on productivity
    13-18
    Views:
    253

    In every economic sector, the enacted and expected quality of the products strongly affects its market entry and subsistence. The aim of management is success, competitiveness and subsistence that require adequate human and material resources and enough production stock. We must also notice that the quality of tools and instruments significantly influences work productivity. This applies to both plant production and animal husbandry.

    The author researched milk production factors with methodical observation, document analysis and interviews. Data were collected with a ten-year interval, thus this assay can highlight the field, volume and sources of investments during this period and that the production stock increased in most farms and decreased in few. The data also shows the influence of investments on work productivity - there are differences between farms of equal size, so there are still ways of development.

  • Ecotoxicological impact of DON toxin on maize (Zea mays L.) germination
    35-40
    Views:
    516

    Fusarium graminearum is one of the most significant arable pathogen in Hungary, and various types of trichothecene mycotoxins (mostly DON, deoxynivalenol) are detected most commonly in cereals (Biró et al., 2011). Fusarium infection and mycotoxin production could not be eliminated, and infected maize by Fusarium sp. cannot be exploited as food, seed, or animal feed. However it can be raw material of biogas production. In this research we would like to investigate the content and effect of the toxin in the end product of biogas production on plant germination. The Fusarium sp. can cause mildew and seedling mortality in seed of maize (Zea mays L.), so we examine the effect of this on germination. In preliminary examination Fusarium sp. was not detected in the bioreactor of the Institute after the retention time (30 day), however it can be assumed that during the hydrolysis of the fungus growth and mycotoxin production also increased exponentially. There were no appropriate tools to detect the toxin in the end product of biogas production so modelling of anaerobic hydrolysis was necessary. The effects of hydrolyzed product for germination were also detected.

  • Insect base-protein: A new opportunity in animal nutrition
    129-138
    Views:
    914

    The 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.

     

  • The influence of fertilization and tillage method on the formation root system capacity and grain production of spring barley
    89-93
    Views:
    244

    To evaluate the interaction of year x variety, year x tillage method and year x fertilization on the grain yield and root system capacity (RSC) of spring barley, we ran polyfactorial field trials in agroecological conditions of a warm corn production area in Slovakia, at  Malanta, in 2009 and 2010. The RSC measurements were done using LCR - meter at a frequency of 1 kHz and they took place in four growth stages: at leaf development in the stage of four leaves (RSC1), in full tillering (RSC2), in the stage heading (RSC 3) and at the stage of ripening (RSC4). The values of grain yield, RSC1, RSC2, RSC3, RSC4 reached in 2009 comparison to 2010 were significantly lower. The highest yield in 2009 was reached by variety Marthe (4.49 t.ha-1) and by variety Bojos (7.19 t ha-1) in 2010. The highest values of RSC in observed growth stages were achieved by variety Bojos in 2009, and in 2010 also besides RSC1. Within both years, difference in yields between tillage methods was not observed. The values of RSC in growth stage of 4 leaves and tillering was higher at conventional tillage, butthe values of RSC3 and RSC4 were higher with minimized tillage. The highest grain yield and values of RSC in every growth stage were achieved on the fertilization variant “c“ in 2009 and on the fertilization variant “b“ in 2010. The correlation relationships between grain yield and RSC were significant and positive in every growth stage. The strongest relationship was found among grain yield and RSC (r=0.6047).

  • Climatic water balance in Hamelmalo, Eritrea
    69-76
    Views:
    471

    Agricultural production is an important sector for peoples to live, but it is highly affected by climate change. To have a good production we need to understand the climatic parameters which adversely affect production. Hamelmalo, which is located in the semi-arid area of Eritrea, is vulnerable to climate change and this is realised in the total production loss. Nevertheless, there is no concrete reference about the climate of the region due to lack of data for a long time. Changes in precipitation (P), evapotranspiration (ET) and, implicitly, in the climatic water balance (CWB), are imminent effects of climate change. However, changes in the CWB, as a response to changes in P and ET, have not yet been analysed thoroughly enough in many parts of the world, including Eritrea. This study also explores the changes of the CWB in the Hamelmalo region, based on a wide range of climatic data (P, relative air humidity and evaporation pan necessary for computing potential evapotranspiration (PET) with the pan evaporation method) recorded at Hamelmalo from 2015-2019. This analysis shows that the annual cumulative CWB for Hamelmalo is negative in 67% of the years. The dry season without precipitation leads to negative CWB and the change in CWB only starts from the raining or crop season. Based on this recent study, 2015 had the highest PET and lowest P, and this resulted in the lowest CWB in the investigated period. Opposite to this, 2019 had lower PET and highest P, which led to the highest CWB. However, the monthly values of CWB did not correlate with the annual P or ET. On the base of our study, it can be concluded that PET and P were very variable in the investigated years and P was the most influential elements of CWB.

  • Significance of biogas production in Hungary
    127-129
    Views:
    234

    It is known that the quantity of fossil energy sources are rapidly reducing, therefore it is necessary to determine a new direction which has to point directly to renewable energy sources. Increasingly comes into view the agriculture’s energy producing nature next to it’s traditional food producing one. The enviromental protection is connected to the energy production by the ultilization of biomass for energy purposes, within the biogas production has an emphasized importance. Quasi every organic material can be used in biogas production, such as: food processing by-products, manure, sewage sludge, hoousehold waste.

  • Does the feeding frequency influence the growth performance of European perch juveniles (Perca fluviatilis) during intensive rearing?
    123-128
    Views:
    390

    The European perch (Perca fluviatilis) is a predatory fish species. Its aquaculture production is increasing worldwide. Feeding and the frequency of feeding are important elements of intensive fish rearing. The aim of our experiment was to examine the optimal distribution of the amount of feed, at the same feed rations. The experiment lasted 42 days. Three treatments were applied in 4–4 replications. The first treatment was feeding twice per day (T2), the second treatment was feeding three times a day (T3), and the third group was fed four times a day (T4). 10 European perch juveniles were stocked per tank, with an individual mean body weight of 3.93 ± 0.06 g at the start of the experiment. The survival rate (S%) was above 90% for all treatments. The T2 treatments produced the most favourable harvest weight (13.96 ± 0.14 g) and specific growth rate (SGR = 3.08 ± 0.01% day-1), but no significant differences were observed between groups. In terms of feed conversion ratio, the best result was obtained by (T3) (FCR =1.06 ± 0.18 g g-1), but no significant difference was found for this indicator neither. The results of the trial indicate that the feeding frequency does not influence the production parameters.