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  • Evaluation of tree measurements after the reconstruction of tree-row system in five narrow streets of Debrecen
    217-222
    Views:
    149

    Viable urban environment is largely dependent on the size, condition and distribution of urban green spaces within and around cities. Treerows in streets are one of the most essential elements of urban green spaces. The aim of this study was to evaluate tree taxa compositions and lifespan values of trees in tree-row system with special reference to five narrow streets (Garai, Jókai, Tanító, Csokonai and Zsák) of Debrecen. Tree numbers, tree taxa and the origin of tree taxa were determined in two years (2009 and 2017). As a next step, six selected taxa (Pyrus calleryana 'Chanticleer', Acer tataricum, Sorbus intermedia 'Browseri', Magnolia kobus, Acer platanoides 'Olmsted', and Crataegus x lavalleei 'Carrierei') were further estimated for the following lifespan parameters: i) trunk diameter (cm), ii) tree crown size (m), iii) trunk status (in 0–5 grades), iv) tree crown status (in 0–5 grades), v) estimated tree viability (in 0–5 grades), and vi) tree value in Ft. Our results showed that the numbers of tree taxa were 9 and 11 in 2009 and 2017 as well as an overall 279 and 282 trees were evaluated in 2009 and in 2017, respectively. More than 60% of the trees were native or similar to native taxa. The largest and the lowest trunk diameters were achieved for Pyrus calleryana 'Chanticleer' and for Acer tataricum, respectively. The largest and the lowest tree crown diameters were achieved for Acer platanoides ’Olmsted’ and for Magnolia kobus, respectively. The best and the worst trunk statuses by 2017 were achieved for Pyrus calleryana 'Chanticleer' and for Crataegus x lavalleei, respectively. The best and the worst tree crown statuses by 2017 were achieved for Pyrus calleryana 'Chanticleer' and for Acer tataricum, respectively. The best estimated tree viability status was achieved for Pyrus calleryana 'Chanticleer' and for Acer platanoides. Overall tree values were 2.73 times higher in 2017 compared to 2009. In conclusion, this study clearly demonstrated the importance of appropriate choice of tree taxa for an establishment of tree-row system in narrow street conditions.

  • Effect of Rootstocks on Blooming Capacity and Productivity of AppleCultivars
    14-20
    Views:
    98

    The experiment with three different rootstock cultivars was set up in a commercial apple orchard at Nagykutas, which is situated in the western part of Hungary. The aim of our two-year-study was to determine the effect three different growing rootstock cultivars (M9, MM106 and seedling) on the flowering and productivity of 33 apple cultivars. Our observations included the following measurements: the date of the beginning and the end of flowering, flower density, fruit density, fruit numbers per tree and tree productivity. According to our results, it was found that the different growing rootstocks have a great determining effect on the above measurements. Our results showed that the flowering period was similar for all cultivars on the three different rootstocks. However, the flowering and the fruit setting decreased in the order M9, MM106 and seedling rootstocks. In contrast, the fruit number per tree followed, in decreasing order, MM106, seedling and M9 rootstocks.

  • Quality comparison of selected apple cultivars under ULO-storage
    62-75
    Views:
    79

    Our examination was carried out in the 103 ha apple orchard of the Kasz-Coop Ltd.. The plantation works with modern varieties standing on M9 root stock, planted in a tree density of 2500 tree/ha and treated with professional integrated technology. The date of harvest is defined by a combination of several ripening analyses methods. The orchard has its own ULO-system warehouse.
    Used in the experiment were four apple varieties: ’Idared’, ’Golden Reinders’, ’Jonagold’ and ’Braeburn’.
    While under ULO-storage, we took 20-25 piece samples 6 times regarding the four varieties, from which 5-5 pieces were kept under three weeks’ shelf life, measured on a weekly bases. In our research, we analysed the dynamics of the flesh firmness and the refractometric value under ULO-storage and three weeks’ shelf life, and the standard deviation dynamics of the refractometric value under ULO-storage.
    Analyses were based on the following measurements: flesh firmness, refractometric value and number of mature seeds.
    We looked for morphological and morphological-quality correlations.
    Through these we described the dynamics of the flesh firmness and the refractometric value under ULO-storage and three weeks’ shelf life for each variety. We referred to the stability of these attributes and to the dynamics of their change. Later, with the help of these, and also considering our practical experience related to the measurements, we characterised the four varieties.
    We found a positive correlation between the seed number and the flesh firmness in the case of the ‘Idared’, ‘Jonagold’ and ‘Braeburn’ varieties, but no correlation was found in the case of ‘Golden Reinders’ in this concern. We visualized the standard deviation dynamics of the refractometric values under ULO-storage. This allowed us to categorise the varieties.

  • Growth and yield patterns of black locust (Robinia pseudoacacia L.) sample trees affected by site conditions: case studies
    125-128
    Views:
    30

    The trees removed from the long-term experiment plots are available for the measurements as lying trees. Through the determination of the volume in sections along the stem, the stem form, the stem volume and other factors can be specified. The comparison of the stems of individual trees of first and third yield classes of black locust (Robinia pseudoacacia L.) stands shows that site conditions have a main effect on the yield (mean tree volume). The difference can be as high as 53% at the age of 30 depending on the sites. To determine the growth patterns based on tree volume is rather a new approach in the light of the relevant literature. The obtained results also highlight the importance of choosing the appropriate tree species for a given site.

  • Comparative study of newly-bred black locust clones with regard to photosynthetic rate and water use efficiency: early evaluation
    5-10
    Views:
    195

    Black locust (Robinia pseudoacacia L.) is one of the most important tree species in Hungary, due to its positive economic impacts. Research to increase its yield, improve its stem quality and enhance its drought tolerance has been ongoing since the 1960s. Of the current research works in this field, the clone trial of the Forest Research Institute, University of Sopron, established in 2020 in the Nyírség region, is worth highlighting. In this experiment 4 newly-bred clones and a state-approved black locust cultivar ('Üllői') are being tested. In the summer of 2022, ‘on site’ measurements of assimilation parameters – net assimilation (An), transpiration (Tr) – were carried out using the LI-6800 portable photosynthesis system. From the data obtained, the water use efficiency (WUE) was calculated. The results of the statistical analysis (Kruskal-Wallis H test) have shown significant differences (p < 0.05) between the clones for all three parameters (An, Tr, WUE) tested. The NK2 clone has performed the highest value for all the parameters studied. However, no significant differences were found between clones NK2 and PL040 for Tr or between NK2 and control ('Üllői') for WUE. Studies of this kind contribute to the improvement of black locust growing through the production and selection of cultivars, which are relatively resistant to the negative effects (drought) of climate change.

  • Preliminary studies to evaluate the use of spectral data in monitoring of apple orchard parameters
    37-41
    Views:
    91

    The introduction/application of precision agricultural technologies has more important role in various fruit growing sectors among others apple growing. Remote sensing methods can detect electromagnetic waves where the green colour of the leaf is responsible for the chlorophyll content. The absorption of chlorophyll is in the wavelength range of 450–670 nm. Samples of apple tree leaves were taken on a weekly basis from the apple orchard at Horticultural Unit of Pallag on University of Debrecen in 2019 summer. Our studies were performed on 2 cultivars (Early Gold, Golden Reinders) and the samples were processed using 2 methodologies: a non-destructive spectral method and spectrophotometric method chlorophyll and carotenoid contents were calculated, which were created into some groups and compared with the spectral values. When the plant begins to lose strong green colour and turns yellow spectral measurements show that chlorophyll content decreases as the proportion of chlorophyll-carotenoid in the plant changes.  In case of grouping into intervals, it can be observed that as the chlorophyll content increases the reflectance value decreases continuously due to the strong absorption. Based on the results, close relationship between the pigments can be detected.