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  • Testing a biological active plant extract’s antifungal effect against soil fungi
    247-252
    Views:
    244

    In Hungary today is about 5 million hectares of agricultural land contaminated with ragweed. The ragweed problem a year is about 60 billion HUF to be paid, of which 30 billion are used to reduce the agricultural damage. Experiments with ragweed pollen has mainly been carried out in connection with terms of allergy. The other biochemical experiments and studies with this plant, have so far been the scientific horizons of public life, boosted the edge. We wanted to demonstrate that the ragweed, which is a weed, containsbiological active (for example: antifungal) compounds. For our experiments in the previous cycle of flowering, plants were collected manually, with its roots and with each plant part. The extraction of the substance from dry plant – meal was carried out using appropriate solvents. The biological activity of ragweed-extracts were tested against fungi isolated from soils and meadow with different mode of cultivation. Our results suggest that ragweed contains biologically active substances, which inhibit the growth of fungi, depending on the concentration of active ingredients of the plant.

  • The role of non-optimum Fe-Zn ratio in the development of latent zinc shortage in cucumber (Cucumis sativus L.)
    7-11
    Views:
    247

    The general micronutrient deficiency of the soils influences the quality of food production which causes human health problems in several countries as well. The non optimal Fe-Zn ratio can cause latent zinc deficiency – which the plants response in the function of their sensitivity –what has no visual symptoms or the plant shows deficiency symptoms in case of appropriate zinc supply. This phenomenon can cause significant decrease in the crop yield.

    The aim of this study was to prove the role of non optimal Fe-Zn ratio in the evalution of latent zinc deficiency.

    The non optimal Fe-Zn ratio caused decrease in the number of the leaves, the number and length of the internodes, the relative chlorophyll contents and in the dry matter production. According to the results the non optimal Fe-Zn ratio caused difficulties in the metabolism, which decreased the examined plant physiological parameters in the most cases. It can be concluded if there are higher iron contents in the tissues than zinc it can result latent zinc deficiency.

  • Seasonal changes of photosynthetical parameters as a results of forest gap model
    133-136
    Views:
    412

    Photosynthetic parameters of English oak (Quercus robur L.) as a member of Querco robori-Carpinetum were investigated in two different habitat in terms of gap forest management: in the gap and in the host forest. The artifical opening process of the forest resulted in more light for growing saplings and need for acclimatization. Photosynthesis is one of the most important way for plant life and plant production. In the centre of photosynthetic efficiency the quality and quantity traits of photosynthetic pigments are standing. During our work some photosynthetic parameters of plants (in the gap and in the forest as well) were measured: relative chlorophyll content as SPAD index, chlorophyll a and b content, total chlorophyll content and ratio of chlorophyll a and b. Based on our results no significant differences among our data in early spring. Although, during the summer significant differences occurred between the measured values in the gap and in the forest area. Lower total chlorophyll content was experienced in the gap, than in the forest area due to the lower chlorophyll-b content. Because of the high light intensity higher chla/chlb ratio was measured in the gap. The lower chlorophyll contents of gap habitat may have a part of the acclimatization process of photosynthetic apparatus against high light stress, which can determinate the survival chance of individual.

  • The toxic effects of aflatoxin microorganisms in plants used as spices
    59-62
    Views:
    227

    As an extension of the analysis of black, white and capsicum peppers for aflatoxins , we have examined an additional 11 types of spices and
    4 herbs for these mycotoxins. The investigations consisted of assessment of the applicability of available methods of analysis and modifications of
    these, where necessary together, with a limited survey of each spice and herb for aflatoxins. The analysis of 13 types of ground spices reported
    the presence of low concentrations of aflatoxins in some samples of black pepper, celery seed, and nutmeg. We decided to include in our study 5
    of the spices examined by these workers (cinnamon, celery seed, coriander, nutmeg, and turmeric) for a comparison purpose. In addition we
    examined ginger, mace, cumin seed, dill seed, garlic powder, onion powder, and the herbs marjoram, rosemary, thyme, and sage.

  • Nutrient Uptake of Miscanthus in vitro Cultures
    23-24
    Views:
    251

    The large biomass production and the low necessary input fertilizer make Miscanthus an interesting, potential non-food crop with broad applications, e.g. for fuel and energy, for thatching, fiber production, for the paper and car industries, as well as for ethanol production.
    Axillary buds of Miscanthus x giganteus were placed on a shoot inducing nutrient solution (modified Murashige and Skoog, 1962), basic medium supplemented with 0,3 mg l-1 6-Benzylaminopurin. After 40 days of culturing, the axillary buds produced three times more shoots than could normally be harvested. The nutrient content (N, P, K, Ca, Mg) was measured several times during culturing. The results showed that, after 35 days, nitrogen and phosphate were nearly completely taken up. From that time, shoot growth was not observed.
    After shoot propagation, the plants were transfered into a nutrient solution for root formation (modified Murashige and Skoog, 1962), basic medium supplemented with 0,5 mg l-1 Indole- 3-Butyric acid, and could be potted in soil after about 14 days.

  • Spatially Discrete GIS Analysis of Sampling Points Based on Yield and Quality Analysis of Sugar Beet (Beta vulgaris L.)
    32-37
    Views:
    341

    Fulfilment of the increasing quality requirements of sugar beet production can be analysed with sampling of plants and soil at the cultivated area. Analyses of the spatial characteristics of samples require exact geodetic positioning. This is applied in practice using GPS in precision agriculture. The examinations were made in a sample area located in north-western Hungary with sugar beet test plant. According to the traditional sample taking procedure N=60 samples were taken in regular 20 x 20 m grid, where besides the plant micro and macro elements, the sugar industrial quality parameters (Equations 1-2) and the agro-chemical parameters of soils were analysed. Till now, to gain values of mean, weighted mean and standard variance values, geometric analogues used in geography were adapted, which correspond to the mean centre (Equation 3), the spatially weighted mean centre (Equation 4), the standard distance (Equation 5), and the standard distance circle values. Robust spatial statistical values provide abstractions, which can be visually estimated immediately, and applied to analyse several parameters in parallel or in time series (Figure 1). This interpretation technique considers the spatial position of each point to another individually (distance and direction), and the value of the plant and soil parameters. Mapping the sample area in GIS environment, the coordinates of the spatially weighted mean centre values of the measured plant and soil parameters correlated to the mean centre values showed a northwest direction. Exceptions were the total salt and calcium-carbonate contents, and the molybdenum concentration of the soil samples (Table 1). As a new visual analysis, the spatially weighted mean centre values of the parameters as eigenvectors were projected to the mean centre values as origin. To characterize the production yield, the raw and digested sugar contents of the sample area, the absolute rotation angles of the generated vectors were determined, which indicate numerically the inhomogenity of the area (Figure 2). The generated spatial analogues are applicable to characterise visually and quantitatively the spatial positions of sampling points and the measured parameters in a quick way. However, their disadvantage is that they do not provide information on the tightness and direction of the spatial correlation similarly to the original statistical parameters.