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  • Complex assessment of inland water fish stocks
    74-80
    Views:
    337

    In the domestic fish production, natural waters have yielded for several years about 7-8 thousand tons. This, from the point of view of outputs, considering the almost 130 thousand hectares of natural water, is rather low, it means approximately 55-60 kg/ha mixed fish.Although the various natural waters can differ significantly on the basis of yields, yet on the majority of the territories, the results were low. In the case of our extensive still waters and rivers, the reason can undoubtedly be found in the combined effect of the lack of the possibility of reproduction of the fish stock and the over-fishing. Fishery built on planning supposes the best possible knowledge in the given circum stances of the parameters of the water area and its fishstock. Lacking this knowledge, it is not possible to establish the optimal use fulness of the resources, what is more, the management can make faulty decisions – as a result of a lack of information -, which can risk the success of later activities.
    It is known that many factors have an impact on the success of the fishery, as well as some information in connection with the water area and the fish stock are necessary, the knowledge of which make it possible to manage the fishery in a planned way. One part of the information is available, while the other part is incomplete or not deep enough. The necessary data are dissimilar depending on their nature, can be obtained from different places, by different methods.
    As the first step for executing the field surveys and processing data, I developed a complex model, which contains in a unified system the steps of estimating the fishstock. I made the sampling on the basis of this. Part of the model is a fish faunistic survey, as well as a morphological survey of the water area. The information gained from these are important for making more accurate the system of devices of the samplings for stock estimation (duration, number of net-rows) and for assigning its place (places representing the best way the physical characteristics of the given water area). The major stages of stock-survey: A) faunistic survey, B) physical survey of the bed, and C) sampling with the help of gill-nets. This is followed by the evaluation by the computer module.
    The results of the research create a methodological and technical background for the fish faunistic and population biologic surveys still performed in different ways in our country, and by applying these methods together, all basic information about natural waters which help decision-making concerning fisheries can be obtaine deffectively.

  • Effects of cultivation methods on some soil biological parameters of a meadow chernozem soil (Vertisols)
    61-66
    Views:
    173

    The effect of extended drought conditions on soil, the unfavourable cultivation technologies and the application of chemicals have been enhancing the processes of physical and biological soil degradation, so the fertility of soil is gradually declining. 
    The effects of two cultivation methods – traditional ploughing (TP) and conservation tillage (CT) – on the biological activity of a meadow
    chernozem soil were examined in a long term experiment. Different parameters of the biological activity of soil were determined. These are
    the numbers of total bacteria, microscopic fungi, aerobic cellulose decomposing bacteria, as well as the activities of some important soil
    enzymes and CO2 production.
    Conservation tillage seemed to be a more favourable cultivation method for the majority of microorganisms, the activities of urease and
    dehydrogenase enzymes and CO2 production, compared to the traditional ploughing system. These parameters increased significantly,
    especially in the upper layer of conservation tillage plots. Concerning the plant cultures, the majority of microbiological parameters were
    higher in the soil of vetch (Vicia sativa L.) depending on the cultivation methods, so involving the pulses to the crop-rotation seems to be
    very important in this soil type.
    According to the ninth year’s results, the importance of conservation tillage as a means of protecting the soil biological activity in meadow
    chernozem (Vertisols) can be established; it was proven by microbiological investigations.

  • Associations analysis of production traits with leptin gene T3469C polymorphisms in pig
    39-43
    Views:
    534

    The aim of this study was to define the connection between the leptin (LEP) gene T3469C polymorphism and its potential association with production traits in improved hybrid pigs. The study included data from 397 gilts and barrows from 2 different sample. The polymorphism was identified by using the polymerase chain reaction-restriction fragment-length polymorphism (PCR–RFLP) method with HinfI restriction enzyme. Two alleles of LEP gene were identified: T (0.93) an C (0.07). The analysis of values of production traits, depending on LEP genotype did not reveal significant (P≤0.05) differences. In the examination the loin diameter (between the 2nd and 3rd ribs), the live weight at slaughter and the averege daily gain during fattening were higher at pigs with C allele than pigs with TT genotipe. Accordingt to our data the effect of C allele was favourable in this population, because these animals had bigger bodyweight without valuable change of lean meat percent.

  • Effect of genotypes and cropyear on thedifferent cultivation parameters of asparagus (Asparagus officinalis L.)
    31-34
    Views:
    319

    The experiments were performed in the Research Institute of Nyíregyháza Research Institutes and Study Farm, Centre for Agricultural Sciences University of Debrecen of 1500 m2 asparagus plantation. The asparagus was planted in 2011. We were determine the number of shoots, plant height and fold thicknes of asparagus hybrid. We can continuously monitored the growing parameters of asparagus. The harvest of asparagus was started in 2013, so we were able to measure to quantity. The weather was characterized by warm and matched precipitation in the growing season (April–July) in 2011 and 2012. Contrarily, the weather was very hot and dry after the late frost in 2013. The Vitalim produced the largest quantity, then the Cumulus and the end of Grolim hybrid. Number of shoot and plant height sequence is identical to the previous one. The Grolim asparagus hibrid has the largest basal diameter.

  • Changes of relative chlorophyll content at maize smut inoculated hybrids
    55-58
    Views:
    647

    The leaf chlorophyll content analysis is important for several reasons. The natural or anthropogenic stressors directly effect on the chlorophyll content. Through the measurement of the chlorophyll content it is possible to obtain data concerning the physiological status of the plant, moreover the chlorophyll content is closely related to the nitrogen content, so it is linked to photosynthesis and the photosynthetic activity which determine biomass production.
    One of the most common symptoms of plant diseases is the larger and smaller interveinal chlorotic areas. These might be local, or expand to the whole plant. There are multiply reasons of chlorosis such as reduction of chlorophyll content, unfavorable effects on the chlorophyll content,disorders regarding function of chloroplasts or ultimately destruction of the chloroplasts. Although such a chlorotic deviancy can contribute to significant losses in photosynthesis; however the underperformance photosynthesis of the sick plants is a more complex process.
    As we unambiguously experienced during our investigations on common smut that the infected maize plants most common accompanying symptom was chlorosis on the leaves, so it is especially important to examine how the infection influenced on the chlorophyll content of different hybrids.

  • Dietary fibre prevalence and its role in human nutrition
    9-13
    Views:
    455

    The role of dietary fibre and its impact on health is increasing. It is worth noting that their beneficial effects on the body are becoming more widely known, but their consumption is still below the recommended daily intake from food. Dietary fibre, as a class of compounds, includes a mixture of plant carbohydrate polymers, both oligosaccharides and polysaccharides. Dietary fibre has been linked to a number of diseases, as its consumption can reduce the risk of cardiovascular disease and type 2 diabetes. They influence the composition of the bacteria present in the human gut. Consuming the right quantity and quality of dietary fibre can play a role in the prevention of certain types of cancer. Nowadays, it is common to produce various fibre-enriched foods, called functional foods, because of the beneficial effects they have previously had on the body. In the present work we want to give a general description of dietary fibre and its role in the body.

  • Examination of the Effect of Cropyear on the Yield Potential and Yield Stability of Winter Wheat Varieties
    62-67
    Views:
    402

    Variety selection is one of the most important, determinative elements of sustainable winter wheat production. Yield potential, and yield stability are the most important elements in the variety selection of winter wheat, but baking quality parameters play an important role, too.
    Several winter wheat varieties were tested for yield and yield stability on chernozem soil in the Hajdúság (in the eastern part of Hungary), in the 2001-2002-2003-2004 cropyears. The management factors were the same for all cropyears. 15 varieties in early the maturity group, 14 varieties in the middle maturity group and 4 varieties in the late maturity group were tested in the above mentioned cropyears. The climatic conditions were average in 2001, dry in 2002, extremely dry in 2003, and very favourable in 2004.
    We obtained 5298-6183 kgha-1 yield from early maturity varieties, 5683-6495 kgha-1 from middle, 5694-6031 kgha-1 from late ones in the average of four years. The cropyears had strong influence on the yields, even on chernozem soil, and were characterized by excellent water – and nutrient – husbandry. Averaging of cropyears and genotypes, we obtained 6984 kgha-1 in 2001 (average cropyear), 5452 kgha-1 in 2002 (dry cropyear), 3120 kgha-1 in 2003 (extremely dry cropyear) and 8400 kgha-1 in 2004 (optimum cropyear), respectively. The yield differences between the minimum and maximum yields were 885 kgha-1 in early varieties, 812 kgha-1 in middle and 337 kgha-1 in late maturity varieties, respectively. The varieties characterized by high yield potential and the varieties characterized by good yield stability were different, so in variety selection we have to take both genetic traits into consideration. There were positive, significant correlations among the yields of winter wheat varieties (early, middle, late), the temperature of spring months. (March-April), and the rainfall of spring months (March-April) (R2=0,703**-0,768** and R2=0,681**-0,749**, respectively). We found a high negative correlation between the temperature of early summer months (May-June) and the yields of wheat varieties (R2= -0,856**- -0,918**).
    According to the results of our experiment, it is very important to harmonize yield potential and yield stability in the variety selection of winter wheat.

  • Evaluation of tourism in the Erdőspuszták sub-region
    95-100
    Views:
    158

    The Erdőspuszták sub-region established an Association of Local Municipalities in 1992, 10 settlements of which set up the Erdőspuszták Association in 1995, as a voluntary organization. One third of the settlements in Hajdú-Bihar county are handicapped from an economic or infrastructural point of view.
    Tourism has become the most dynamically developing industrial sector. Unfortunately, in Hungary and, especially, in the eastern region, this way of earning a living is still in its infancy. Nevertheless, these areas possess such untouched natural values, cultural monuments and unexploited possibilities which could attract tourists.
    In my study, the problem is examined from two aspects. First, interviews with mayors are included, consisting of three questions. The leaders of the settlements were first asked about the impact of EU accession, then the most important development plans were mapped and finally the local tourism plans were investigated. Second, I have made an evaluation of each settlement which reviews the infrastructural and environmental conditions, the accommodation and boarding possibilities offered the different tourist attractions and leisure possibilities.
    The development of tourism can be an obvious solution to this problem. The toots of tourism entails the creation of job opportunities, the development of infrastructure, the enhancement of living conditions. It has a diverse effect and it contributes to the improvement of living standards in rural areas.
    Regarding tourism, it can be stated that each settlement has its own image and value, which the citizens are proud of. It has been realized that collaboration between the settlements could greatly contribute to the development of a tourist programme of several days length, as a result of which the guests would spend more time in the region, which would be beneficial to everybody. My suggestion is that the settlements should work out a plan for the development of tourism jointly, in which they would determine the targets, describe the specific development plans and tasks and elaborate the ideas for the different investments.

  • Analysis of small ruminants’ semen under the cooling, deep-freezing and sex-orientation method
    53-58
    Views:
    252

    The aim of this study was to examine the influence of cooling, deep-freezing and sex-orientation methods on fertility of ram and buck semen. It was pointed out that deep-freezing and sexorientation methods had a more considerable destruction on both semen compared with the effect of cooling method. However, with the development of the sex-orientation method, the results of  lambing had a significant increase in sheep. On the other hand, the NRR of the inseminations with deep-frozen ram semen exceeded most of previously publicated results. Being interesting, and hopefully useful benefit in practice that the analysed buck semen samples are shown more favourable results in all methods compared with the same results of rams.

  • The effect of dried herbs on the souring of sunflower oil
    87-89
    Views:
    290

    Many herbs have antioxidant activity, which can replace the use of potencionally harmful synthetic antioxidants. Sunflower oil fortified with eight different plants and stored at room temperatur in my experiment. Specified intervals with determination of peroxide value, FFA, iodine value, anisidine value and TOTOX value followed the quality of the sunflower oil.

  • Daily behaviour of Hungarian Grey Cattle under range grazing conditions
    45-48
    Views:
    369

    Cattle behaviour on rangeland depends on external factors, such as grass allowance and quality, temperature, net solar radiation, distance from water-source, wind speed and direction, air pressure changes and the applied breeding technology. Our research is based on previous empirical observations and modern methods to analyze the behaviour of the Hungarian Grey Cattle. Today it is crucial to use cost-effective solutions in modern beef cattle farming therefore we introduce a cost-efficient method to study and follow cattle herds. We are studying relation between traveled daily distance and air pressure. The various weather fronts influence behavioural characteristics and traveled daily distance. According to our hypothesis, the pressure-change and the wind direction has significant effect on cattle activity on pasture. As the different air masses alter the barometric conditions and unbalance the neuroendocrine system, indirectly cause relaxed or agitated behaviour

  • Values of Hungarian pigeon breeding
    9-14
    Views:
    455

    Pigeon breeding has a history dating back several centuries in Hungary. It has internationally renowned and accepted results. Our aim was to estimate the range of values related to Hungarian pigeon breeding and draw attention to the importance of their conservation. We studied the biological values of native breeds and the appearance of pigeon breeding within the Hungarian culture. These include the use of the symbol, the relating beliefs and customs, language, gastronomy, architecture and object values, as well as the community-building effect. Based on our results we can say that this topic is worthy of further research.

  • Effect of the plant density on different maize (Zea mays L.) hybrids yields and leaf area index (LAI) values
    51-56
    Views:
    320

    We have investigated the plant number reactions of three maize hybrids of various genotypes in a small-plot field experiment. The plant numbers were 50, 70 and 90 thousand ha-1, while the row distances were 45 and 76 cm. The experiment was set on the Látókép Experimental Farm of Centre for Agricultural Sciences of the University of Debrecen in four replications on calcareous chernozem soil.

    The assimilation area and the leaf area index have important role in development of the crop yield. The studied three different genotype maize hybrids reached its maximum leaf area index at flowering. The maximum leaf area index increased linearly with increasing plant density. The season-hybrids reached less yield and leaf area index. According to our experimental results, we have concluded that with the decrease of the row spacing, the yield increased in the average of the hybrids. The studied hybrids reached the maximum yield at 70 and 90 plants ha-1 plant density. We determined the optimal plant number that is the most favourable for the certain hybrid under the given conditions.The higher plant density was favourable at 45 cm row spacing than 76 cm. The hybrids reached the maximum grain yield at 45 cm row spacing between 76 712–84 938 plants ha-1, while the optimum plant density at 76 cm row spacing changed between 61 875–65 876 plants ha-1.

    The leaf area index values between the applied plant density for the flowering period (July 1, 24), we defined a significant differences. In the archived yields were significant differences at the 45 cm row spacing between 50 and 70, 90 thousand ha-1 plant density, while the number for the 76 cm row spacing used did not cause a significant differences in the yield. There were significant differences between the examined hybrids of yields.

  • Effect of the claw disorders on production performance in dairy cattle
    15-19
    Views:
    325

    The aim of the study was the influence of claw disorders on production traits in dairy cattle. Observed were claw traits as claw angle, claw length, heel index, claw height, claw diagonal and claw width. Right hind claw after functional trimming was evaluated. Occurrence of claw disorders like interdigital dermatitis and heel erosion (IDHE), digital dermatitis (DD) and sole ulcer (SV) as well as the progress of disease were observed. Basic summary and variation statistics was performed by the SAS software. Two herds were included in the study. Holstein dairy cows (n=101) produced 11 875 kg of milk, 468 kg (3.94%) of fat and 396 kg (3.34%) of proteins. Holstein cows were affected with IDHE in 22 cases, with DD in 6 cases and with sole ulcer in 10 cases. Slovak Simmental dairy cows (n=101) produced 5834 kg of milk, 258 kg (4.44%) of fat and 209 kg (3.59%) of proteins. Slovak Simmental cows were affected with IDHE in 8 cases, with DD in 5 cases and with sole ulcer in 19 cases. Observed was that claw disorders caused deviations of milk production.

  • Influence of temperature and variety on seed germination of soybean (Glycine max L. Merr) at different germination times
    5-12
    Views:
    427

    Seed germination is an important stage in crop development that affects plant performance, crop yield, and quality. Many factors influence seed germination, and one of the most important factors is temperature. The closer the temperature is to the optimum, the faster germination will occur. Temperature affects seed germination in various plants and varies depending on the variety. Therefore, the effect of temperature on seed germination is necessary to investigate, also for soybean varieties. Soybean is one of the world's most valuable oil-seed crops. Generally, proper seedling establishment and germination of soybean seeds are crucial processes in the survival and growth cycle of the crop. Thus, a study was done to investigate the influence of temperature and variety on soybean seed germination at different times after sowing. The experiment was carried out at the Institute of Agronomy, Hungarian University of Agriculture and Life Sciences (MATE), Crop Production Laboratory. Seeds of two soybean varieties were subjected to three different temperatures: 15, 25, and 35 °C, and two soybean varieties, Martina and Johanna were tested. There were four germination times based on the days after sowing: Days 3, 5, 7, and 9. This experiment was set up with a completely randomized block design and four replications. According to the findings of this study, the Martina variety showed a better germination rate as well as higher vigor and viability than the Johanna variety in the first 12 days after sowing. At temperatures of 15 °C and 25 °C, both varieties achieved comparable percentages of viability, but they were more vigorous at 25 °C due to better total seedling length. Thus, the information gained from this study will indirectly determine and confirm the proper temperature for the initial growth of the Martina and Johanna varieties.

  • The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
    89-96
    Views:
    1076

    Aquaponics 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. 

  • The effect of gamma irradiation on the germination and growth of Turda Star maize hybrid dry samples
    23-25
    Views:
    161

    In order to study the effects of gamma rays on germination indices i.e. germination index (GI), total germination (GT) and the
    germination energy (GE), of maize hybrid, Turda Star current experiment was conducted. Dry seeds of Turda Star maize hybrid were
    irradiated with 2, 5, 15, 30 and 50 Gy, using a 60Co-gamma radiation source.
    Results showed that gamma irradiation affected all the above mentioned parameters except germination percentage. Total
    germination and germination energy was significantly affected at higher doses of gamma rays. However, increasing doses of gamma
    rays did not have significant effects on seed germination percentage. The other growth parameters showed declining tendency with
    increasing doses of gamma irradiation.

  • Effect of Planting Time of Maize on Factors Influencing Yields in 2001-2002
    112-116
    Views:
    180

    In this paper we analysed the results of maize planting time experiments by the Department of Crop Sciences and Applied Ecology of the University of Debrecen, Centre of Agricultural Sciences in 2001. We made the experiments at the experimental garden of DE ATC in Hajdúböszörmény.
    We examined in 2001, 2002 ten hybrids with three planting times. The results were analysed by analysis of variance with two factors. In 2001 the yields were high, between 7.2-11.6 t/ha. The seed moisture contant of hybrids was 6-8% less after early planting than after late planting. The vegetation period of the hybrids became longer after early planting, which helped the drying-down of the hybrid and determined the seed moisture content at harvest to a great extent.
    In 2002 the yields were high, between 4.02-10.47 t/ha. The seed moisture contant of hybrids was 5-14% less after early planting than after late planting.
    On the basis of the above, variety specific technologies should be applied where the planting time is adapted to the hybrids. In accordance with the other cultivation factors.

  • Crop Load, Fruit Thinning and their Effects on Fruit Quality of Apple (Malus domestica Borkh.)
    29-35
    Views:
    712

    Crop load, a quantitative parameter used by industry, is generally defined as the number of fruit per tree. It is often expressed in terms of number of fruit per trunk cross-sectional area (fruit/TCSA). Crop load is the most important of all factors that influence fruit size, and the removing of a part of the crop is the most effective way to improve fruit size.
    The potential size of a given pome fruit is determined early in the season and growth proceeds at a relatively uniform rate thereafter. This uniform growth rate permits the accurate prediction of the harvest size of the fruit as early as mid-summer. The growth rate, once established, is not easily altered, and fruit numbers, therefore, can affect fruit size only within definite limits and maximum effectiveness requires adjustment in fruit numbers relatively early in the season. It was established, that „thinning does not change a potentially small fruit into a large fruit, but rather insures that a potentially large fruit will size properly.” Emphasis should be on estimating fruit numbers rather than fruit size.
    Fruit thinning can quickly reach the point of diminishing returns. Rather than a high percentage of large fruits, the objectives of thinning should be the elimination of the smallest fruits, improved fruit quality and annual production. Fruit thinning is accomplished by hand or chemical thinning. Chemical thinners are separated into categories as bloom thinners and post-bloom thinners. Early removal of potential fruit (blossom thinning) is currently used in many apple producing areas to enhance flower initiation for next year’s crop and thus, return bloom. It also results in reduced competition for photosynthates. Blossom thinners usually have a caustic effect on floral parts.
    The amount of fruit left on a tree should be determined by the vigor and general condition of the tree. Leaf area per fruit affects the number of spurs flowering the following season. It can be difficult to separate timing and fruit number effects in crop loading studies, as abscission rates after hand thinning of retained flowers/fruitlets tend to very with the time of hand thinning.

  • Comparative analysis of the transformation of Hungarian and East German agriculture
    164-170
    Views:
    176

    Agriculture, and within it, the development and later transformation of the cooperative system shows many similarities between Hungary and the Eastern German provinces. A few examples can be mentioned, such as the mistrust against the notion of cooperation, the forced development of the cooperatives and, as an occupied territory, the influence of the Soviet Union. Similar issues emerged in both countries’ agriculture and the measures taken were also alike. Similar social, economic processes and changes were started at the end of the 1980s (1989/90) and these had a significant effect on the areas that serve as a basis for this study.

  • The effect of reduced sprinkler programs on the main fungal pathogens of apple in environmentally sound production systems
    13-16
    Views:
    275

    Aim 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. 

  • Opportunities for improving the nutritional value of cereal-based products
    275-278
    Views:
    905

    We set up experiments for improving the nutritional value of cerealbased products. Our aims were to decrease the energy content of bakery products with the mixing of plant originated raw materials and byproducts with high fibre contents, and we have evaluated the effect of sodium-chloride on the physical properties of bakery products. We found that the apple pomace, the byproduct of juice production, is excellent for increasing of fibre content of bakery products and the further aim of investigation is to develop economical ways of hygienic byproduct handling and purification. Our experiments, evaluate the bakery use of triticale, have significant achievements and the breads made from triticale flour and whole-grain are commercially available nowadays. Our investigations included the possibilities of decrease of toxin contamination of cereals and our results can form a part of risk estimation systems after further experiments .

  • Effect of plant extract against opportunist human pathogen soil bacteria
    89-93
    Views:
    224

    Our experiments have repeatedly shown that the extract of ragweed (Ambrosia artemisiifolia) is an antifungal and antibacterial component.
    In our paper we tested of the biological activity of the herbal substance against opportunistic human pathogenic bacteria strains (Staphylococcus
    aureus 110003 and 25923; Staphylococcus saprophyticus 110008). Our laboratory tests show that the extract is bacteriostatic and in several cases bactericid. We can assume that from the the agricultural and public health aspects can be extremely dangerous weed, contains biologically active components and it may be suitable for the prepare of antibacterial agents.

  • Examination of physical properties of final product and drying properties of combined (convective pre-drying and freeze finish-drying) dehydration method
    5-12
    Views:
    302

    In this study, the effects of freeze drying (FD), hot-air drying (HAD) and combined drying (HAD-FD) on drying characteristics, energy uptake, texture, rehydration and color of carrot were investigated. Results showed that HAD-FD significantly improved the drying time compared with FD under the same operating conditions, and the HAD-FD can reduce the total cost of dehydration. The drying kinetics was described by the Henderson-Pabis and the third degree polynomial models in the case of HAD, FD and HAD-FD. The HAD carrot samples were exhibited shrinkage, case hardening, poor rehydration and brown surface. The FD carrot cubes appeared porous structure, excellent rehydration, soft texture and loose color. The HAD-FD samples were superior to HAD products and was nearer in quality to FD products with respect to appearance, rehydration and surface resistance (texture). Finally, it is concluded that HAD-FD is effective in improving the FD drying rate. However, the combined drying has a small-scale adverse effect on product quality.

  • The effect of various composts on vegetable green mass on two soil types
    179-183
    Views:
    427

    Composting of sewage sludges makes easier the utilization of sewage sludge in the agriculture and the composts in good quality could increase the nutrient content of soil. Due to the composting process, the sewage sludge composts with high organic matter content can be utilized in the same way as other composts or farmyard manure.
    Composts produced in different ways have different effects on the physical, chemical and biological properties of different soils, although their positive effects have already proved in the literature. In our study the effects of composts from different composting processes were investigated in soil-plant systems. The different physical and chemical properties of the two examined soil types (arenosol and chernozem)strongly influenced the nutrient supply capacity of composts which could be characterized by the growth of ray-grass as a test plant in the pot experiment. In this work we examined the effects of three different composts on the green weight of plants on the fourth and eighth weeks after the treatment and sowing.