prilagođeno pretraživanje po punom tekstu

ŠUMARSKI LIST 5-6/2019 str. 33     <-- 33 -->        PDF

pedunculate and Turkey oak young crop in mentioned favourable conditions. This multi-flush young crop maintains higher values of height growth compared to the one-flush growth that was confirmed in this Hungarian oak field experiment study as well.
The importance of multiple flushing of different oak species (sessile, pedunculate and Turkey oak) in the early stages of ontogenetic development, as an ecological adaptation to different environmental conditions was investigated from the aspect of physiology (Masarovičova, 1989), morphology (Masarovičova and Požgaj, 1988) and the results are important for silviculture of oak forests.
The knowledge about the growth characteristics, and thus of the multi-flush growth, is very important for the process of seed regeneration in different conditions. For instance, in the growing conditions of the research of Ovington and MacRae (1960), sessile oak mean height of one-year-old seedlings was the lowest in the conditions of the highest light intensity (11.6 cm), while in the most shaded conditions the plants had a height of 17.1 cm. The similar pattern was found by Jarvis (1964) and Ponton et al. (2002) where the mean height of one-year-old sessile oak seedlings is higher going from relative light intensity of 20 to 100% and 8 to 100%, respectively.
The results from previously cited studies are pointing out that different oak species are showing different growth reactions regarding height growth in different light conditions. This may be in relation to the multi-flush growth. The knowledge about the height growth characteristics, i.e. its norm of reaction enables the creation of conditions that favours the most desired part of the norm of reaction from the aspect of silviculture in the natural regeneration from seed using suitable silvicultural measures.
The presented results regarding Hungarian oak one-year-old seedlings are contributing to a better understanding of the ecology of the species in the initial stage of development. The results are in compliance with the growth characteristics that are found in some other oak species in well illuminated conditions. Therefore, they can be considered as a good basis for further investigations of optimal growth of this valuable, meso-xerothermic oak species that should have greater management importance in the territory of Serbia and southeastern Europe, having in mind the climate changes.
On the basis of 400 analyzed one-year-old Hungarian oak seedlings in the growing conditions of the field experiment in full light conditions, the following can be concluded:
1. The mean height of one-year-old Hungarian oak seedlings is 9.71 cm; mean root collar diameter 3.65 mm; the mean number of leaves per seedlings 7.9 and the mean total leaf area 80.18 cm2;
2. The height growth of Hungarian oak seedlings developed through up to three height growth flushes (growth phases) and three growth types of seedlings were defined: one-flush growth, two-flush growth and three-flush growth type;
3. In the analyzed sample, 39.8% of the plants belonged to one-flush, 58.2% to two-flush and only 2.0% to three-flush growth type;
4. The one-flush growth seedlings have less leaves and lower values of height, root collar diameter and total leaf area, but they are characterized by a higher mean height of the primary axis (the height of the first flush of growth), compared to the multi-flush growth seedlings. This is pointing out to different growth characteristics in the initial stage of development and during the growing season between different types of seedlings;
5. The multi-flush growth seedlings are characterized with higher variability of analyzed elements compared to the one-flush seedlings, and the positions and shapes of the models of distributions are clearly pointing out to the differences between the one-flush and multi-flush growth seedlings;
6. The phenotypic variability based on the presence of multi-flush growth shows that, from the silvicultural aspect, it is important to define the conditions that favour the occurrence of multi-flush growth of Hungarian oak since it has a significant influence on total height, root collar diameter, number of leaves and the total leaf area of one-year-old seedlings.
This study was supported by the Ministry of Education, Science and Technological Development, Republic of Serbia [Project No. III43010; III31041; III43007].
Bercea, I., 2013: Germination, upshot and growth of Hungarian and Turkey oak seedlings in the woodlands of the western part of the Getic Plateau. Oltenia 29(1): 145–150.
Bobinac, M., 1994: Višefazni rast u visinu jednogodišnjih biljaka lužnjaka i neki aspekti značajni za semenu obnovu, Šumarstvo 1-2, 47–57.
Bobinac, M., 1997: Characteristics of Turkey oak (Quercus cerris L.) seedling growth on regeneration areas with different light, Proceeding book of the 3rd ICFWST, Volume II, Faculty of Forestry Belgrade, 128–134., Belgrade.