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  • Vegetative and micropropagation potential of Piper guineense (Schumach and Thonn)
    29-36
    Views:
    388

    The continuous loss of forest plants due to deforestation, and the increasing demand for Piper guineense because of its medicinal and food value, has put a permanent pressure on its population in the wild where it is collected. A method for conservation and mass propagation is therefore required. This research was undertaken to determine the optimal concentration of auxin needed for vegetative propagation and to investigate the potential of Piper guineense for micropropagation. The auxin optimization study of vegetative propagation was based on the use of two-nodal stem cuttings treated with five different concentrations of indole-butyric acid (IBA). Growth parameters such as the number of sprouted, rooted and survived cuttings among others were determined. To investigate the potential of Piper guineense for micropropagation, nodal explants were subjected to different sterilizing treatments using ethanol, NaOCl, mancozeb, streptomycin and Plant Preservative Mixture (PPM). The effect of plant growth regulators (PGRs) was tested on sterilized nodal explants using full strength Murashige and Skoog (MS) hormone-free media alone as control and MS media supplemented with PGRs (BA, NAA and KIN) at different concentrations and combinations. Significant differences were observed across the treatments for all growth parameters measured. However, 2000 ppm IBA significantly (p<0.05) influenced sprouting and rooting of the stem cuttings. Piper guineense explants have deep tissue contaminants, which cannot be eradicated by surface sterilization alone except double sterilization using PPM. On control media, neither shoot nor root response was observed while the highest percentage of induced roots was obtained from explants cultured on MS +1 mg/L BA + 0.25 mg/L NAA. Shoot induction was only achieved when BA was used alone and when subcultured on media supplemented with NAA, which generated roots.

  • Antioxidant capacity, total phenolics and mineral element contents in fruits of Hungarian sour cherry cultivars
    59-64.
    Views:
    1211

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. Fruits of sour cherry contain a wide range of antioxidant compounds including melatonin, perillyl alcohol, ellagic acid, several flavonoids, polyphenolics, and anthocyanins. This study was carried out to survey the antioxidant power and mineral element content of seven commercial sour cherry cultivars and three cultivar candidates and to assess the influence of some external conditions on fruits' functional properties. Our analysis revealed nearly 5- and 2-fold differences between the lowest and highest antioxidant capacities and total phenolics content, respectively. Some cultivars (`Kántorjánosi' and ‘Újfehértói fürtös') and cultivar candidates (D, 'Petri' and 'Éva') showed outstanding antioxidant capacity and total phenolic content; in addition, mineral element content in fruits of the ‘Újfehértói fürtös' cultivar was also favourable. Redox parameters of fruits were influenced by the cultivation plot or fruit positions within the canopy in about half of the cultivars tested. Genetic background of cultivars forms the decisive factor in determining fruits' antioxidant capacity, although external factors may have also sizeable modifying effects. Enhanced functional properties of the fruit may also be further increased through breeding programs since considerable variation exists within the tested germplasm.

  • Examination of nitrogenous compounds in Hungarian bio-musts
    109-113.
    Views:
    456

    There has not been any research done on the musts from organic grapes. As a result of the special technologies in organic farming we can expect bio-musts to have a different quantitative and qualitative composition of nitrogen compounds from that of traditional musts. In our present essay we deal with the tests of nitrogenous compounds (assimilable nitrogen content, aminoacid, biogenic amine content) in musts from Hungary's bio-wine cellars. Our results show that the change in procedures has resulted in neither quantitative nor qualitative changes in the nitrogenous compounds of bio-musts.

  • Comparative evaluation of chamomile (Matricaria recutita L.) populations from different origin
    91-95.
    Views:
    666

    In our research project under cultivation we examined 4 cultivars ('Soroksári 40', 'Lutea , 'Goral', 'Bona') and 28 wild populations of chamomile assuring all of them the same environmental conditions. Plant height, flower-diameter, essential-oil content, and the main terpenoid and flavonoid composition were analysed. The aim of our study was to establish the genetic background of breeding a new cultivar as well as encircle those natural habitats that give chamomile drug with the best quality.

    In the case of plant height populations from the Great Hungarian Plain were lower than plants from Transdanubia and the control cultivars. Between the wild and the standard individuals we found significant differences with relevance to the flower-diameter. With regard to the essential oil content the populations were very heterogeneous even those, which came from the same habitat. Populations form Transdanubia and Nagyiván reached the essential oil level of the cultivars (0.721-0.931 gi100g), and 75% of the examined plants exceeded the minimum requirement of the PhHg VIII.

    According to the essential oil composition our previous statement was confirmed that in the populations of Transdanubia and Northern part of Danube—Tisza Mid Region the main component is bisabolol-oxide A (30-41.2%), while plants native to the territory cast of the river Tisza are mainly characterised by a-bisabolol (32.3-48.4). In some samples the ratio of bisabolol-oxide B was more than 10%. The chamazulene content was higher in the cultivars selected to this component (above 20%), than in the wild populations (varied between 1.22 and 17.2%). Populations originated from the central part of Hortobágy region had extremely high apigenin content (10-13 mg/g), but in the case of chlorogenic acid, hyperoside and quercitrin we did not find any differences affected by the origin.

  • Evaluation of sour cherry varieties grown with environmental technology
    39-41.
    Views:
    4600

    The evaluation of a produce is an important moment of predicting its success on the market. The general impression, which is decisive, when a consumer chooses to purchase the commodity, should be interpreted in more objective, measurable terms. Primary data have been collected on fresh fruits derived from different growing technologies by organoleptic tests and the data filled up in the forms are processed with correlation analysis. The components were: taste, aroma, flesh firmness. The coefficients of correlation showed that the rest of characters as the appearance, juiciness, and the sugar/acid ratio.

  • Carbohydrate utilization of Erwinia amylovora in vitro
    31-34.
    Views:
    379

    Nectar is a multi-component aqueous solution that promotes bacterial multiplication. The concentration of nectar in plant flowers is not stable since it is under the influence of environmental conditions, especially free moisture and relative humidity. Experiments were conducted with "artificial nectar" and directed along two lines: (1) determination of the optimal concentrations of carbohydrates for the growth of E. amylovora development (2) consumption of different carbohydrates besides basic sugars.

    Solutions of "artificial nectar" were prepared in different compositions by changing the dominance of basic sugars (fructose — glucose —sucrose) in proportions of 2:1:1, 1:2:1, 1:1:2 and between concentrations of 10-0.6% (diluted with Basal minimum broth) in order to determine optimal conditions for the development of E. amylovora.

    At a basic sugar concentration of 10% bacterial multiplication started and continued until I log degree (from 106 to 107 cfu/ml). At concentrations of 5% and 2,5 % cells developed with nearly the same kinetics (from 106 to 8x107 cfu/ml and from 106 to 9x107 cfu/ml, respectively). Multiplication was more pronounced and nearly the same at concentrations of 1.2 % and 0.6 % (from106 to 2x108 cfu/ml). At a basic sugar concentration 30% total sugars bacterial multiplication did not occur, while at 20 % it was negligible, not measurable photometrically.

    At minimal concentrations of F, G, S (between 1-0.1 %) bacterial cells were still able to multiply, producing organic acids from sugars.

    Our study showed that E. amylovora requires only a small amount of sugars (0.1%) for multiplication (acid production) while high concentrations inhibit multiplication. There was a negative correlation between sugar content and cell density. The optimal range of sugar concentration was at about 1%.

    Effect of "less frequent carbohydrates" to E. amylovora multiplication was also determined using the API 50 CH strip. We could provide information on utilization of 39 carbohydrates by the bacterium at different categories as follows: Not utilized-, Slowly and weakly utilized-, Slowly and completely utilized-, Quickly and completely utilized carbohydrates. We suppose that carbohydrates that belong to the latter two groups could play an important role as nectar components in promoting E. amylovora multiplication in the blossoms of pome fruit trees.

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