No abstract

Variations in the photosynthetic pigments and total carbohydrate contents of needles of different age classes (current-year, 1-year-old, 2-year-old and 3-year-old) of Pinus nigra subsp. pallasiana (Lambert) Holmboe trees in a young natural stand were investigated during the growing season. In current-year needles, total carbohydrate content was lower during June and July when the needle growth continued than in older age classes, but it was similar to other age classes in the months of August to October. Seasonal patterns of variations in total carbohydrate content were almost similar in 1-, 2-, and 3-year-old needles. Chlorophyll and carotenoid contents increased from May to June, remained relatively constant or declined slightly during summer and autumn in 1-, 2-, and 3-year-old needles. In October, the pigment content was highest in 1-year-old needles, and lowest in 3-year-old needles. Our study indicated that total carbohydrate and pigment contents were affected by needle age classes and seasons.

Background and Purpose: Natural or artificial regeneration, rehabilitation, and conversion from coppice to high forest are important practices in Oriental beech (Fagus orientalis Lipsky) forests in Turkey. Studies of the seeds of this species have increased in number because mast years are infrequent and seed germination is inhibited by dormancy. In this study we quantified the effects of tree age (40-59, 60-79 and 80-99 years), stand exposure (north, west, east and south) and elevation (600 and 800 m a.s.l.) on seed characteristics (germination, moisture content, and weight) of Oriental beech. Material and Methods: The seeds used in this study were collected from natural beech forest at Kumluca, Bartin, in the western Black Sea region of Turkey. Experiments were carried out in the laboratory and the greenhouse of Bartin University. Results: Seed germination and moisture content varied significantly by elevation, and seed germination was strongly influenced by elevation. Moisture content was 14% at 600 m and 16% at 800 m. The effects of elevation and tree age on 100 seed weights were not significant but exposure had a significant effect. The highest 100 seed weight was recorded for trees on southern exposures and the highest germination percentage of 82% was recorded for trees on northern exposures. Conclusions: In conclusion, since oriental beech seedlings are produced by generative propagation method, seeds should be harvested in optimum distribution area of beech, from average ages and phenotypically plus tree.

Stone pine (Pinus Pinea L.) is a multipurpose species for Mediterranean forestry owing to both economic and socioeconomic importance. Thus, in this study the effects of magnetic field on the germination of seeds and growth of seedlings of stone pine were investigated. For this purpose, its seeds were treated by a magnetic field of 9.42 mT for a different period of time-0 min (control), 15 min, 30 min and 40 min in a cylindrical shaped sample, made of a nonmagnetic thin transparent plastic sheet. Germination experiments were conducted in the greenhouse of Bartın University. Considered the germination results as a whole, while seeds exposed to a magnetic field for 30 and 45 minutes resulted in higher germination energy (43%) and percentage (55%), respectively. Both the lowest germination energy (6%) and germination percentage (32%) were found out to be in the seeds without applying magnetic field. Magnetic field increased shoot height, root collar diameter and also tap root length of stone pine seedlings. In terms of shoot height, 85% of 1+0 seedlings was proper for afforestation activities based the classification of TSI. Moreover, magnetic field treatments may be considered as an alternative method to enhance germination Stone pine seeds and to obtain better growth characteristics of their seedlings.

No abstract