No. 1 (2019)

Published May 23, 2019

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Articles

  • The synthesis of selenium nаnоpаrtiсle (SeNPs) – Review
    5-8
    Views:
    414

    Selenium is an important dietary miсrоnutriеnt required for the nоrmаl physiоlоgy and mеtаbоlism of humans and аnimаls. The biоlоgicаl prоperties оf selenium nаnо pаrticle depend оn their size аnd fоrms. Sеlenium nаnоpаrticle (SeNPs) аttrасts еvеn mоrе аttеntiоn, thanks to its high biоаvаilаbility аnd muсh lоwеr tохiсity thаn inоrgаniс аnd оrgаniс fоrms. In this review, I summаrized the infоrmаtiоn аnd wаys оf prоductiоn оf selenium nаnоpаrticle. SeNPs hаve been prоduced in chemicаl, physicаl, аnd biоlоgicаl wаys. In recent years, biоlоgicаl wаys hаve been especially important in the prоductiоn оf selenium nanoparticles.

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    441
  • Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
    9-14
    Views:
    303

    Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.

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    241
  • Determining the optimal age of breeding gilts and its impact on lifetime performance, Literature review
    15-20
    Views:
    568

    Lifetime sow performance is a critical indicator for producers managing a commercial sow herd. It is comprised of sow longevity, lifetime piglets born alive, lifetime number of pigs weaned and lifetime non-productive sow days. Increased lifetime performance and longevity in sows reduces costs of replacement gilts and improves herd performance and profitability (Sasaki et al., 2008, 2011). One of the most critical factors driving the performance of sow herds is gilt management. Decisions regarding gilts have profound effects on sows’ lifetime performance. Age at first breeding of a gilt is a management decision that has been shown to affect performance and retention of the gilt in a herd.

    The main aim of this review is to establish factors affecting age of first breeding of gilts and its impact on lifetime performance.

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    479
  • Development of an InDel marker set to establish hybridization between wild boar and domestic pig (Sus scrofa) breeds
    21-25
    Views:
    311

    Wild boar and domestic pig breeds belong to the same species (Sus scrofa), so they can easily have viable offspring. This could be a problem in preserving the genetic lines of wild boars, keeping clean the food industry from lower-grade hybrid boar meat, and „producing” ethically questionable trophies, too. The aim of our study was to develop a cost-efficient, fast, easy and accurate marker set which can separate the wild boars from hybrids and domestic pig breeds.

    The InDel markers were developed using 59 full pig genomes of 17 different breeds (e.g. Duroc, Large White, Landrace, Mangalica, wild boar). Sequence differences between the genomes of wild boars and domestic breeds were identified in variant call files, and verified using the IGV software. Wild boar, mangalica and duroc specific primers to amplify the chosen InDel regions were designed using Primer3.

    After preliminary tests five markers were chosen, three wild boar specific, one Mangalica specific and one Duroc specific one. Fluorescently labelled primers were used to make the valuation easier and more accurate with capillary electrophoresis instead of gel-electrophoresis. The markers were optimised individually and in multiplex conditions and tested in samples of 11 breeds.

    In conclusion, a new, faster and cheaper set was developed to separate the wild boars from the hybrids and domestic breeds. Based on the preliminary testing on wild boars, duroc and mangalica breeds zero samples resulted false negative, so it is 100% accurate. In addition, it is a much more cost- and time-effective way than testing every single sample with STR sets.

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    268
  • The Carpathian lingonberry, raspberry and blackberry fruit extracts feature variable antimicrobial efficiency
    27-32
    Views:
    365

    Wild berry is an excellent source of phytonutrients and/or bioactive compounds associated with significant therapeutic properties, so that they have been utilized in folk medicine and traditional nutrition throughout centuries. Multiple health-promoting effects, such as anti-inflammatory, anti-diabetic, anti-heart and coronary disease properties were attributed to such wild berries. It has also been proved that berries could feature antimicrobial effects that could be of a great importance for the prevention of food-feed poisoning and fighting back antibiotic resistance.

    In this study, we investigated the antimicrobial properties of lingonberry (Vaccinium vitis-idaea), raspberry (Rubus idaeus) and blackberry (Rubus fruticosus) crude and ethanolic extracts prepared from fruits obtained from the spontaneous flora of Eastern Carpathian Mountains situated in Transylvania. The antimicrobial effect of crude and alcoholic extracts were assessed on four Gram-negative, five Gram-positive bacteria and one yeast species using the agar diffusion method. The studied bacteria can cause food or feed spoilage and foodborne diseases. Our results indicate the significant inhibitory effect of lingonberry extracts in the case of Gram-negative bacteria like Proteus vulgaris and Salmonella Hartford, while among Gram-positive bacteria the strongest inhibitory effect was observed for Bacillus species like B. cereus, B. subtilis, B. mojavensis and Micrococcus luteus. The raspberry and blackberry extracts featured milder inhibitory effects in the case of the studied bacteria species. Furthermore, we have studied the crude or ethanolic extract combinations associated antimicrobial effects synergistic/additive or antagonistic properties. Interestingly, the triple and double ethanolic extract mixes had stronger antimicrobial properties, whereas the crude extract mixes showed relatively reduced effects, if any. Our results indicate that the antimicrobial activity of studied fruit extracts obtained from wild berries can vary upon the applied extraction method and their combination formulae, so that all these considerations must be taken into account when such fruit extracts are considered for foodstuff development.

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    316
  • Optimizing fish structure in angling ponds focusing on white fish
    33-36
    Views:
    188

    According to new amendments of laws, commercial fishing licenses of natural waters shall not be issued from the calendar year 2016 in Hungary. However, the most settlement of white fish to angler ponds originated from natural waters. Currently, there is no sufficient quantity of fish species belonging to this group available to fulfil the settlement commitments of fish farmers. The aim of this recent study is to develop a breeding and production technology that is suitable for settlement of large quantities of this fish species of appropriate length of (4–5 cm). The following methods are investigated: aquaculture cage system (pond-in-pond system), monoculture and mixed population with different ratio of white fish in fish structure. Due to the different environmental needs of different fish species, many parameters need to be investigated, for example: stocking density, feeding, oxygen level, monoculture or mixed populations, growth potential and mortality. A preliminary experiment was carried out following the artificial propagation of ide (Leuciscus idus) following a 21-day larval rearing experiment in which the effect of different stoking density was investigated for mortality and growth. On the basis of the expected results, the optimal conditions for the aquaculture cage system will be described, regarding to the white fish stock.

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    218
  • The effect of breed and stage of lactation on the microbiological status of raw milk
    37-45
    Views:
    351

    The microbiological quality of the milk is important not only for food safety, but it can also influence the quality of dairy products. The microbiological status of raw cow milk can be influenced by many factors. Our aim was to determine whether there was a difference between the microbiological quality of milk of two different cow breeds (Holstein Friesian and Jersey) kept and milked in the same conditions, and how the microbiological quality of the raw cow milk changed during lactation (beginning, mid, and end). Samples were taken and analysed in July, August and September in 2018 from two dairy farms in Hajdú-Bihar county. During the conducted studies, the total plate count (TPC), the coliform count, the Staphylococcus aureus count and the coagulase-negative Staphylococcus (CNS) count of raw milk samples were determined.

    There was no significant difference (P>0.05) between the milk of the Holstein Friesian and Jersey breeds in the case of TPC. However, the mean coliform count of milk samples taken from Holstein Friesian cows was significantly lower (P<0.05) than the mean coliform count of milk samples taken from Jersey cows. S. aureus was detected in one of the twelve milk samples taken from Holstein Friesian cows, and in two of the eleven milk samples taken from Jersey cows. CNS was found in larger amount in milk samples taken from Holstein Friesian cows, and the difference was significant (P<0.05). Both TPC and CNS count were significantly higher (P<0.05) in individual milk samples taken at the end stage of lactation, than in samples taken in the earlier stages of lactation from Farm “A”. However, in the case of Farm “B”, there was no significant difference (P>0.05) in colony counts at different stages of lactation. S. aureus was only present in milk samples that collected from cows, which were at the beginning and middle stages of lactation. Testimg the hemolysin production ability of S. aureus strains isolated from the raw milk samples, only weak hemolysis was observed on blood agar. In case of antibiotic resistance testing, it was found that all strains were susceptible to cefoxitin, chloramphenicol, clindamycin, erythromycin, gentamicin, penicillin G, tetracycline and trimethoprim/sulphamethoxazole.

    Based on the results of our studies, staphylococci were detected in a higher amount in the milk of Holstein Friesian cows, and coliform bacteria were detected in a higher number in the milk of Jersey cows. Summing up the results of the milk samples taken from the different stages of lactation in one of the farms, it can be concluded that higher TPC and CNS count could be detected at the end stage of lactation than in the samples taken from the earlier stages of lactation. The fact that at the end of lactation the microorganisms could be detected in a higher colony count may be related to the fact that teats could be damaged during lactation by the milking machine, which increased the chance of imvading the microorganisms into the udder.

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    255
  • Bacteria in the milk of sheep with or without mastitis- mini Review
    47-52
    Views:
    380

    From a nutritional point of view, sheep milk is more valuable than cow and goat milk and the interest for sheep milk is increasing in many countries. However, sheep milk is easily contaminated during milking, handling, and transport and it is an ideal medium for bacterial propagation. Consequently, sheep milk spoils quite quickly. The proper, clean handling of milk is not only of sanitarian interest, but it also serves the farmers’ interests, because contaminated milk may not be distributed, and is unsuitable for producing good quality products. Following this technological trend, this review addresses the bacterial composition of sheep milk with and without mastitis. Even though sheep milk contains a lot of bacteria, this review article highlighted total plate count, Enterobacteriaceae, coliform, Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Campylobacter, Salmonella spp. and Streptococcus spp. Mastitis in sheep is a vital cause of mortality, reduction in milk production and early culling. The reported risk factors for mastitis in sheep were age, a case of mastitis, breed, husbandry systems, and location. The main priority should be implementation of programs to minimize human pathogenic bacteria and mastitis in raw ewe milk.

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    334
  • Development of seed analyses by means of various matrix solutions and the MALDI-TOF MS technique
    53-57
    Views:
    351

    The earth's population is growing steadily, currently accounting for about 7.3 billion people. Population growth causes food demand to rise, approximately 36 million people die each year due to starvation or related diseases. One solution to this problem is the continuous examination and development of the agricultural economy. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI -TOF MS) were used to analyse of sunflower, soybean and hemp. In order to analyse the protein of maize, this method has already been applied. However, for sunflower, soy and hemp, it is necessary to develop a sample preparation method. Choosing the optimal matrix solution for ionization the traget molecule is an essential part of developing the method. Our aim is to compare two different matrix solutions (α-HCCA, SA matrix), based on the properties (intensity, noise ratio, value of spectra) of the spectra.

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    244
  • Results of the sensory analysis of precision maize production
    59-62
    Views:
    248

    This research was carried out in 2018, at the Látókép Experimental Station of the University of Debrecen in a moderately warm and dry production area, on deep humus layered medium-hard calcareous chernozem soil. In the scope of the research, the chlorophyll content of maize (Zea mays L.) was examined under field circumstances by means of local sensory measurements and we were looking for correlation between the obtained values and the amount of yield. Our measurements were carried out with Minolta SPAD-502 and GreenSeeker devices at 3 measurement times (4 leaf stage, 10 leaf stage and silking). It was found that phenological phases had an effect on the obtained SPAD and NDVI values and were in a slightly significant correlation with the yield. The most significant correlation was found between the results obtained during silking and the amount of yield. This may be because the least time has passed between the measurement time and harvest. Results obtained during the 10-leaf stage show excessive values in each case, which can be due to a measurement error. It was found that the phenological phase had an effect on the correlation of SPAD and NDVI values and the amount of yield. As the phenological phase progressed, the correlation between the measured results and yield has increased.

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    459
  • Comparative study of a winter wheat variety and hybrid sown after different pre-crops on chernozem soil
    63-69
    Views:
    254

    Wheat production is a determining branch within Hungarian crop production (produced on nearly one million hectares). Weather anomalies caused by climatic change confirmed the importance of the biological background (variety, hybrid) in wheat production. The adapting ability and reaction of different wheat genotypes towards nutrient supply were studied in a long-term field experiment on chernozem soil type in the case of different pre-crops (sunflower and maize). According to the experimental results of the vegetation of 2017/2018, the yield of the variety Ingenio sown after the sunflower as previous crop ranged between 4168 and 8734 kg ha-1, while in the case of maize as previous crop, this value ranged between 2084 and 7782kg ha-1, depending on the applied nutrient supply level. The studied genotypes produced rather significant yield surplus as a response to the application of mineral fertilization (4.6–5.1 t ha-1 after sunflower and 5.7–6.3 t ha-1 after maize). Optimal mineral fertilizer dosage was determined by both the genotype and the pre-crop. N-optimum values of wheat genotypes was determined using regression analysis. In the case of the variety Ingenio sown after sunflower, the optimum range was N144-150+PK, while after maize, it was
    N123-150+PK, respectively. For the hybrid Hyland, these optimum ranges were N114-120+PK, just as N150-153+PK, resp. The application of optimal mineral fertilizer dosages improved water utilization of the studied wheat genotypes to a significant extent. WUE values of the control, unfertilized treatments ranged between 4.1–8.3 kg mm-1, while in optimal fertilizer treatment, it ranged between 15.5 and 17.4 kg mm-1.

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    210
  • The impact of climatic factors on the relative chlorophyll content and yield of a maize hybrid in a long-term experiment
    71-77
    Views:
    238

    The impact of the climatic factors of crop year on the relative chlorophyll content of maize was examined for three years. The examinations were carried out on the Látókép Experiment Site of the University of Debrecen on calcareous chernozem soil in a small-plot, non-irrigated long-term field experiment with strip plot design. In addition to a non-fertilised (control) treatment, nitrogen (N) fertiliser doses were applied as base and top dressing. The 60 and 120 kg N ha-1 base dressing doses were followed by two top dressing doses at the V6 and V12 phenophases.

    Averaged over the different fertiliser treatments, SPAD readings increased in all three years as the growing season progressed. The highes SPAD value increase was observed in the average crop year (2017) at the V12 phenophase (11.8), which further increased at the R1 phenophas, by 3,7. No significant Spad value difference was observed between the average (2017) and the dry year (2018) at the V6 growth phase. However, in the wet crop year (2016), the V690 treatment provided the statistically highest relative chlorophyll content (46.8). At the V12 phenophase, the base dressing dose of 120 kg N ha-1+30 kg N ha-1 (V6150) showed to be successful in two years (2016 and 2018), while in 2017, the base dressing dose of A60 was successful. The impact of crop year on relative chlorophyll content can be clearly shown at the R1 growth stage. In all three years, the significantly highest relative chlorophyll content could be achieved at different nutrient levels: A60 in 2016, V6150 in 2017 and V690.

    In a wet year (2016), higher yield could be achieved as a result of the 60 kg N ha-1 base dressing and 30 kg N ha-1 at the V6 growth stage (V690) as top dressing in comparison with 2017 and 2018, when higher fertiliser dose (120 kg N ha-1 base dressing and 30 kg N ha-1top dressing at the V6 growth stage) was needed to achieve a significant yield surplus.

    Altogether, averaged over the different treatments, the highest yield (12.48 t ha-1) was observed in the wet year, when the relative chlorophyll content was also the highest (50.6).

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    244
  • The changes of the purple coneflower’s (Echinacea purpurea L.) herb and radix drug yield under different fertilization conditions
    79-83
    Views:
    214

    In this research, the purple coneflower’s (Echinacea purpurea L.) nutrient requirement was examined under different fertilization conditions in a small plot experiment. We measured the medicinal plant’s raw and dry herb and root drug mass and drying loss under different fertilization settings and meteorological factors.

    From the drug’s raw and dry mass perspective, based on the results, in our opinion, the control setting exceeded all nutrient settings’ results in 2016. In 2017 and 2018, the N75P100K150 nutrient setting has the biggest herb yield. As for the root yield, it was also the N75P100K150 setting which produced the biggest yield.

    The Pearson's correlation test was performed to investigate the connection between the quantity of the raw, the dried herbs, the different nutrient settings and meteorological factors.

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    191
  • Pre- and postharvest technologies to extend the shelf life of Prunus cerasus
    85-89
    Views:
    272

    Fresh tart cherry consumption cannot be increased without the development of an appropriate technology for its elongated storage. This requires the development and optimization of the pre- and postharvest treatments. Currently, we have only limited knowledge about tart cherry (Prunus cerasus L.) postharvest technology, however, related studies on sweet cherry (Prunus avium L.) may be adopted. In this article, we have collected the most important research results in this topic.

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    267
  • Comparative study of different soybean genotypes in irrigation technology
    91-95
    Views:
    323

    In many places in Hungary, early maturity soybean can be successfully grown. The earlier maturity group of soy which ripened in 110–125 days in most crop areas in Hungary. However, to achieve excellent results, the selection of proper varieties is important too. Successful cultivation is largely dependent on the macro and microclimate of the production area, the nutrient supply of the soil and the cultivation technology. Soybean can be produced in places where the amount of precipitation is right, as the lack of water results in lower yields and deteriorated oil and protein concentrations. In the following study, 2 years (2016 and 2017) are compared to the yield, protein and oil content of the soybeans of the early maturation group in irrigated and non-irrigated treatments. Based on our experiment, it can be stated that, during the irrigation of soybean, oil and protein content and yields did not always change.

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    224
  • Studying the effects of traits in the genotype of three maize hybrids in Hungary
    97-101
    Views:
    378

    In this study, we selected three hybrids (Armagnac, Loupiac, and Sushi) for evaluation of the effect of traits in genotype in Debrecen. In 2017, the total rainfall from May to October was 314 mm in Debrecen, which was 236 mm in the winter period before sowing. The obtained results showed that there was a positive correlation between the weight of the cob maize and the rate of seed/cob, number of rows with number of seeds in column and outer diameter ear with weight of cob and number of rows in grain per ear and the rate of seed / cob; Also, there was a negative correlation between grain weight in ear with seed/cob rate, outer diameter ear and the rate of seed/cob and outer diameter ear with the number of leaves. There was a positive correlation between stem diameter, Seed/cob rate and the number of nodes by GGE biplot. In addition, there are traits of weight of all seeds and outer ear diameter that had the highest effect on average yield. Moreover, the number of seeds per row showed the least effect on the average yield of hybrids.

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    251
  • Stand evaluation, crop estimation and yield analysis of winter wheat for the optimization of yields
    103-109
    Views:
    136

    The authors have been carrying out stand evaluation, crop estimation and yield analysis in winter wheat since 2012. The sampling areas were assigned at the fields of the Training Farm of the Faculty of Agricultural and Food Sciences of Széchenyi István University Mosonmagyaróvár according to the structure of the cropping system. According to their observations the value of field emergence is always lower than the laboratory germination. The weak emergence is important because the lower plant density cannot be compensated by the increased tillering in spite of having larger plant growth space. It is proven by the fact that they detected strong productive tillering even at 5 and 10 mm plant spacing while there were single-spiked plants at 40-50 mm plant spacing as well. The analysis revealed that the total ear mass and grain mass of wheat plants bearing two or more ears is almost the double than that of the single-spiked plants. It was a further basic experience that the largest ear of ”multiple-spiked” plants is always heavier than the single ear of one-spiked plants. Plants with intense tillering and more ears demonstrate the importance of proper seedbed preparation and drilling and the significance of sowing good quality seeds. These are the factors that determine field germination and emergence, influence the speed and intensity of initial development and by all these factors the sufficient productive tillering. The authors emphasize the use of exact and objective methods at crop estimation, e.g. the relationship between the ear mass and the yield which is in strong correlation whilst ear length and grain mass are not suitable for a precise estimation. The authors conclude that crop estimation and yield analysis must be inevitable tools of modern crop production and will be particularly important in precision agriculture. These tools also qualify the job done by farmers and helps to identify the areas that require special attention.

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  • Promising Leuce poplar clones in sandy ridges between the rivers Danube and Tisza in Hungary: a case study
    111-113
    Views:
    251

    An intensive integrated research and development work has been carried out on the improvement of Leuce poplars including primarily the native white poplar (Populus alba L.) and its natural hybrid grey poplar (Populus × canescens). More than 70 percent of the Leuce poplar stands can be found on calcareous sandy sites in the Danube–Tisza region, so they play a significant role in the poplar management of this part of the country. The most important task ahead of Hungarian poplar growers is to improve the quality of poplar stands and plantations based on selecting new clones and cultivars. The growth and yield of four promising Leuce poplar clones was evaluated on a marginal site in central Hungary. The clones ‘H 425-4’ (Populus alba L. × Populus alba L.), and ‘H 758’ (Populus alba L. Mosonmagyaróvár 124) seem to be suitable for wood production, while the ‘H 427-3’ (Populus alba L. × Populus alba L. cv. Bolleana) and ‘H 422-9’ (Populus alba L. × Populus grandidentata (Michx)) clones (with decorative stem form) could be better used for tree lines and ornamental plantations.

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    193
  • Effects of plant density on photosynthetic characteristics and yield of maize under irrigation condition
    115-118
    Views:
    308

    Maize plant response to plant density is an essential agrotechnical factor used for determining grain yield. Three plant densities (60,000 ha-1, 72,500 ha-1, and 85,000 ha-1) were used in this study to ascertain the effect of photosynthetic parameters and grain yield. Results show a significant difference in the photosynthetic parameters (SPAD, NDVI, LAI) and plant height for plant density of 85,000 ha-1. Grain yield and stem diameter were not significantly affected between the different plant densities.

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  • Investigation of the decomposition and leaching dynamics of Salix, Populus and mixed leaves in the area of Lake Balaton and Kis-Balaton Wetland
    119-124
    Views:
    210

    In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient load and plays a basic structural and functional role in several ecosystems. In Hungary, at the banks of lakes and wetlands, Salix and Populus trees are the most common species. In an experiment in Lake Balaton and Kis-Balaton Wetland between 16 November 2017 to and 3 June 2018, the decomposition rates and leaching dynamics of Salix, Populus and mixed leaves (50% Salix and 50% Populus) were investigated. Total nitrogen and phosphorus content of biomass samples were measured at the beginning and end of the experiment for the leaching dynamics experiment. We found that litter mass losses (Salix, Populus and mixed leaves) were not significantly different between the two mesh size litterbags and between Lake Balaton and Kis-Balaton Wetland. Different amounts of the total nitrogen and phosphorus leaching from Salix, Populus and mixed leaves were detected. The total nitrogen contents of the plant samples were around 8-18% at the end of the investigated period. Slightly higher values were measured compared to phosphorous (27-29%).

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  • The effect of plant density on the yield of sweet potato
    125-128
    Views:
    479

    A field study was conducted in South-East Hungary during the main cropping season of 2016, 2017 and 2018, with the objective of determining the effect of plant spacing on the productivity of sweet potato. Production technology experiments of four repetitions were set up in a randomized block design on sandy soil. The performed treatments consisted of four variations of plant spacing (row distance x plant-to-plant distance): 80 cm x 20 cm, 80 cm x 30 cm, 100 cm x 20 cm, 100 cm x 30 cm. The plant material was the Hungarian registered sweet potato variety ‘Ásotthalmi-12’. Analysis of variance revealed that planting density significantly affected the average yield of storage roots. The highest yield per plant was achieved with the 100 cm x 30 cm (2016, 2017), as well as with the 80 cm x 30 cm (2018) setups. On hectare level, our results showed that the highest plant density of 62,500 plants ha-1 (80 cm x 20 cm setup) could give the highest yield. Comparing the highest tons ha-1 results to those achieved with the plant spacing setups resulting in the highest yield per plant, the differences can be even 13 or 14 tons at hectare level. This finding underlines the importance of choosing the proper planting density towards the higher end.

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