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  • Monitoring raspberry cane midge (Resseliella theobaldi) on the basis of temperature data
    61-64
    Views:
    96

    The ’midge blight’, in which the raspberry cane midge (Resseliella theobaldi) has an important role, is the greatest problem in the raspberry protection. The basis of the chemical protection against raspberry cane midge is the prediction of adult midge emergence. Before the application of sex pheromone traps developed for the investigation of flight pattern, the usage of the accumulated temperature was attempted for the prediction of egg laying, but these temperatures are different in each country. The aim of this paper is to give information on the time of raspberry cane midge emergence and flight pattern by using sex pheromone traps and accumulated temperature calculation.

  • Impact of fertilisation and the fluctuation of precipitation on the ecophysical and production characteristics of maize
    39-44
    Views:
    182

    The aim of this study was to analyse the problems caused by the unfavourable (dry and wet) weather and its consequences in the R1 growth stage of maize (Zeamays L.), as well as their management and the alternatives of preventing yield reduction by using agrotechnical measures fertilisation, irrigation), also, we wanted to examine whether the Chl content measured in the R1 growth phase provides reliable prediction of yield per hectare.

    The examinations were carried out in a moderately warm and dry production area at the Látókép Experiment Site of the University of Debrecen, Centre for Agricultural Sciences on calcareous chernozem soil in 2007 and 2008. Six different N doses (0,30,60,90,120,150 kg ha-1) were used in the irrigated and non-irrigated treatments of the field experiment.

    The results showed that there is a significant strong positive correlation between Chl content and yield both in the non-irrigated (P<0.001, R=0.777) and the irrigated (P<0.001, R=0.801) treatment. The results of the correlation analyses performed yearly showed that weather factors significantly influence the strength of correlations, but these correlations are always positive.

    The Chl content of maize leaves provided a reliable prediction of yield per hectare in the R1 growth stage. In the irrigated treatment, the correlation is always closer than in the non-irrigated treatment.

  • Timing it right: The Measurement and Prediction of Flowering
    17-22
    Views:
    76

    Although the model described here was developed from research in controlled environments, there is now considerable evidence that in can be applied to a very wide range of natural environments in several species. Multi-locational trials augmented by successional sowing and, if considered necessary, supplementary illumination in the field to increase daylength, can be used to estimate the values of the model coefficients: (1) to characterize germplasm collections and so predict flowering behaviour elsewhere; (2) for interpreting and understanding crop adaptation; and (3) for genetic analysis of photoperiod sensitivity. We do not yet know whether the model has any contribution to make to the understanding of the biochemical mechanisms of photoperiod and temperature responses, but at the very least, it should provide the basis for indicating the most appropriate environmental conditions, genotypes and physiological stage of the plants most suitable for such investigations.

  • Upgrading breeding value estimation in beef cattle
    451-458
    Views:
    239

    This paper gives a summary of the possibility for applying genomic information for breeding value estimation in beef cattle breeding. This process is called genomic prediction and is now widely used in dairy cattle globally as well as in some beef and sheep populations. The advantage of genomic prediction is a more accurate estimate of the genetic merit of an individual at a young age thereby facilitating greater annual genetic gain, predominantly through shorter generation intervals. Genomic predictions are more advantageous for sex-linked (e.g., milk yield), low heritability (e.g., fertility) and difficult-to-measure (e.g., feed intake) traits. The larger the reference population, on average, the more accurate the genomic predictions; additionally, the closer genetically the reference population is to the candidate population, the greater the accuracy of genomic predictions. Research is continuing on strategies to generate accurate genomic predictions using a reference population consisting of multiple breeds (and crossbred). Retrospective analysis of real-life data where genomic predictions have been operation for several years clearly shows a benefit of this technology.

  • Supplementary botanical examinations for modelling the grass production of the great pasture of Hajdúbagos
    17-21
    Views:
    74

    Our botanical survey at the great pasture of Hajdúbagos is a part of a broad research that aims to predict the production of the grass at the given area. As the mentioned pasture is a nature conservation area, the usage of artificial fertilizers or other classic grassland management methods in its handling are prohibited. Thus grazing is an important tool for the management of this area, however the not suitably regulated grazing order and the poorly calculated carrying capacity cause serious problems at some parts of the pasture. The prediction of the grass yield is essential to
    avoid both over- and both under-grazing and for determining the optimal number of the grazing animal stock and the grazing method, thus the most suitable management strategy.
    The potential grass yield is easily calculable with a computer model that will be established as a basis for determining the grass production. For the sake of getting an accurate view of the plant associations of the pasture, we created examination quadrates and determined all plant species found in the quadrates. After plant determination, we compiled a coenological table in which we marked besides the scientific name and families, the life forms of each species that refer to the structure, morphology and thus the adaptability of plants to their environment. We determined the
    TWR, so the thermoclimate, water and soil reaction values, the nature conservation values, as well as the covering values of each plant species (DB), and the total coverage of the examination quadrates (B%).
    According to the covering values, grasses proved to be characteristic plants at the examined pasture, thus we need to consider them influential in calculating the animal carrying capacity and with the rest of the information, we need to supply the model.
    The life forms and TWR indicators, all together with the nature conservation values provide further important data to the development of the management suggestion of the protected pasture. By examining these values to different parts of the area, we could get an exact view on the measure of the degradation effects. This promotes the determination of grazing methods and the forming of the boundaries of certain pasture sections, to avoid  those harmful anthropogenic effects that seriously endanger this extensive sandy pasture. 

  • Evaluation of population parameters and biometric data of an Eurasian Collared Dove (Streptopelia decaocto Friv.) population in the Great Plain of Hungary
    89-92
    Views:
    361

    The Eurasian Collared Dove shows different patterns in density all over Hungary. In some cases, the population has decreased to a lower level, but there are habitats where the population remained stable. Several factors were taken into consideration during the evaluation of this phenomenon. These publications state that the increased urbanization of corvids, the lack of food sources, and the changes in nesting sites caused the decrease in numbers. During our research, we intend to contrast the differences in population structure of Collared Doves that differ from each other in the density of predators presented at nesting sites. As a first step, in this paper, numerous samples (n=118) were taken from a population that is less influenced by corvid species’ nest predation. Our prediction was that the population parameters remained at the level of 1980’s, in which the population of Eurasian Collared Dove has reached its maximum, according to further publications.

    During the evaluation process, our data were collected from hunting bags near Nyíregyháza. Results were compared with former publications. We stated that the population structure, such as age and gender distribution remained stable in the evaluated population. In addition, morphometric factors of the collected individuals were also measured, such as weight, wing length, 3rd primary feather, and tail length, which were compared with former surveys. During statistical tests no significant difference was revealed among population parameters, but there were significant differences between most of the morphometric data, (p>0.05).

  • Investigation of genetic diversity in irradiated maize lines and its relation to hybrid performance
    20-26
    Views:
    227

    Knowledge of genetic diversity among available parental lines is fundamental for successful hybrid maize breeding. The aims of this study were to estimate (1) genetic similarity (GS) and genetic distance (GD) (based on Jaccard index) in four maize inbreed lines; (2) to classify the lines according to their GD and GS; (3) to determine hybrid performance based on GD and heterosis for yield ability in 4x4 full diallel system. We used morphological description and AFLP (amplified fragment length polymorphisms) for estimation genetic polymorphism in four maize inbred lines. We estimated the applicability of genetic similarity in SC and reciproc hybrids for prediction of their performance.
    Three primer combinations were used to obtain AFLP markers, producing 207 bands, 70 of whit were polimorphic. The dendogram based on genetic similarities (GS) and genetic distance (GD) and morphological description separated four inbred lines into well-defined groups. Morphological description just with AFLP analysis showed reliable results. In view of genetic distance, the UDL 1 line and their linear and reciprocal crosses showed significant heterosis effect, which was confirmed by heterosis calculation based on grain yield.

  • Application of AquaCrop in processing tomato growing and calculation of irrigation water
    183-187
    Views:
    342

    The area and volume of processing tomato production is increasing in Hungary. Irrigation is crucial for processing tomato growing. To save water and energy, it is important to know exactly how much water is needed to reach the desirable quality and quantity. AquaCrop is a complex software, developed by FAO, which is able to calculate irrigation water needs, several stress factors and to predict yields. A field experiment was conducted in Szarvas in processing tomato stands, under different irrigation treatments. These were the following: fully irrigated plot with 100% of evapotranspiration (ET) (calculated by AquaCrop), deficit irrigated plot with 50% of ET (D) and control (K) plot with basic water supply was also examined. Dry yield, crop water stress index and soil moisture were compared to modelled data. The yields in the plots with different access to water were not outstanding in the experiment. The model overestimated the yields in every case, but the actual and modelled yields showed good correlation. AquaCrop detected stomatal closure percentages only in the unirrigated plot. These values were compared to CWSI – computed from leaf surface temperature data, collected by a thermal cam in July – and showed moderately strong correlation. This result suggests that Aquacrop simulates water stress not precisely and it is only applicable in the case of water scarcity. Soil moisture data of the three plots were only compared by means. The measured and modeled data did not differ in the case of K and ET plots, but difference appeared in the D plot. The obtained results suggest that the use of AquaCrop for monitoring soil moisture and water stress has its limits when we apply the examined variables. In the case of dry yield prediction overestimation needs to be considered.

  • Crop Load, Fruit Thinning and their Effects on Fruit Quality of Apple (Malus domestica Borkh.)
    29-35
    Views:
    376

    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.

  • Terrain Analysis and Stochastic modelling for Archaeological site prediction and landscape reconstruction in the Lake Manyara area, Northern Tanzania
    47-53
    Views:
    190

    In this study we focus on paleontological sites in the area of Lake Manyara and the Makuyuni River Basin, Northern Tanzania. This region is known for Middle Pleistocene fossil finds and artefacts. To analyze the spatial distribution of potential paleontological find locations we applied two different methodologies based on statistical mechanics and on boosted regression trees. The first one is able to handle presence-only datasets such as the locations proper. The second approach was used to study the variable importance and to derive information on the related geo-processes for classified paleontological sites. The locations and their spatial distribution were retrieved from literature and collected by own field work over the last years. For the modeling we utilized environmental information such as spatially continuous layers of topography (30 m SRTM DEM), derivatives of topography, vegetation information as well as ASTER multispectral data as predictor variables. The results reveal
    potential areas where further fossil sites may be located. Moreover, we assessed the processes that are related to sites with specific archaeological evidences. Therefore, the sites were grouped in three categories: i) artefacts sites, ii) fossil sites and iii) mixed sites. We applied boosted regression trees to analyse the processes related to the classified sites. The methodology considers not only site specific characteristics but implicitly also the related pedogenetic and morphogenetic processes. We were able to differentiate between artefact and fossil sites.  Moreover, our analyses indicate an influence of transportation processes on the artefacts, whereas deposition of fossils does not seem to involve large scale transportation. Finally, we show that also the landscape can be reconstructed such as the former lake margin.

  • The dual function of soil: natural resources and production site
    5-19
    Views:
    78

    First, we begin with a review of the global situation, followed by a description of that in Hungary itself. Next, we consider the conditions affecting soil utilization, and their relevant problems. Finally, we make a brief prediction of what can be expected in the coming two decades or so. For this latter reason, it is necessary to briefly illustrate the situation, processes and relationships.

  • Biomass production estimation of processing tomato using AquaCrop under different irrigation treatments
    131-136
    Views:
    215

    The wiser usage of irrigation water is inevitable in the future. Irrigation has very high input cost; therefore, farmers must carry out irrigation with care. Also, the effect of irrigation on crops has a big role in decision making. Modeling provides a possibility to evaluate this effect. AquaCrop, as a crop production simulation model has great potential in this field. The accuracy of tomato biomass yield prediction of the model was tested in this research. For collecting the necessary data, a field experiment was conducted at Szarvas on processing tomato with different water supplies, such as 100% (I100), 75% (I75), 50% (I50) of potential evapotranspiration and a control with basic water supply (C). The relation of the simulation and actual biomass yields was evaluated during the season. Very good correlation was found between the modelled and the actually harvested data. The data for the control and I100 treatments showed higher correlation than the I75 and I50. The relationship for all of the data was moderately strong. Miscalculations occur mostly when the dry biomass yield reaches
    7 t ha-1. The accuracy of the model was evaluated with the use of mean absolute error (MAE) and root mean squared error (RMSE) values. The least error was found in the C treatment, which means 0.34 MAE and 0.45 t ha-1 RMSE. The simulation resulted in higher errors in the I75 and I50 treatments.

  • Comparative studies to model bioavailability of pesticides in distinctive soil types
    17-23
    Views:
    97

    Bioavailability of pesticides is determined by two major factors: soil characteristics and pesticides’ chemical feature. These factors result in a definite adsorption capability whose extent varies on a large scale. By revealing interactions between pesticides and soils it is of high interest to model bioavailability of widely used pesticides, as it is a key element in terms of prospective toxicological aspects. Our work signifies steps forward improving pesticide soil mobility prediction models as we created model systems representing correctly natural relations. Comparison of different solvent extraction methods proved to be an efficient tool to gain information on the bioavailability of some widely used pesticides as well as to model actual environmental processes.
    Comprehensive comparison has been made between different experimental methods by applying 5 extraction models showing diverse efficiency in extracting capability of pesticides. In some cases chloroform excelled in mobilizing pesticides from soil, however mostly application of humic acid solution as extraction model was found to be at least as efficient as methanol, chloroform or CaCl2-solution.
    Four chemically much different pesticide (simazine, acetochlor, chlorpyrifos and diuron) were applied to two soil types (both sandy and brown forest). The extracted amounts were determined by GC/MS technique. Adsorption coefficients (Kd) were also calculated for the examined samples.
    Obtained results for Kd indicated that chemical feature of pesticides seemed to be of utmost importance in terms of soil binding capability preceding the relevance of soil characteristics. Adsorption capability of chlorpyrifos proved to be the most pronounced preceding simazine and the least prone to bind to soil acetochlor and diuron