• Journal of Korean Society of Forest Science
• /
• v.112 no.2
• /
• pp.258-266
• /
• 2023

Pine wilt disease is caused by the pine wood nematode (Bursaphelenchus xylophilus) and has killed many pine trees in Europe and Northeast Asia, including South Korea. Resistance to pine wilt disease varies among species. Previous studies were mostly conducted in nature or greenhouses and only a few in test fields. In this study, seedlings of six pine species (Pinus thunbergii, P. koraiensis, P. densiflora, P. parviflora, P. rigida × P. taeda, and P. strobus) were artificially inoculated by pine wood nematodes in the test field. The Wilt Index was measured every 2 weeks after inoculation in addition to the mortality rate, detection rate, and pine wood nematode concentration measurement after 24 weeks. The pine wilt disease mortality rates were P. thunbergii (80%), P. koraiensis (77.8%), P. densiflora (62.5%), and P. parviflora (22.0%), and both P. rigida × P. taeda and P. strobus survived. The pine nematode detection rates were the same among the species except for P. rigida × P. taeda pine (22.2%). High Wilt-Index values were obtained for P. thunbergii, P. koraiensis, and P. densiflora, which had mortality rates higher than the other species. Furthermore, there were no significant differences in the Wilt Indexes between P. parviflora, P. rigida × P. taeda, P. strobus, and the control group. Statistically, P. thunbergii and P. koraiensis showed high susceptibility to pine wilt disease, P. densiflora and P. parviflora showed moderate susceptibility, and P. rigida × P. taeda and P. strobus showed apparent resistance. These results provide basic data for pine wood nematode resistance breeding or as evidence of the need for afforestation of P. rigida × P. taeda and P. strobus.

• Journal of Korean Society of Forest Science
• /
• v.99 no.5
• /
• pp.693-697
• /
• 2010

Biomass expansion factors that convert the timber volume (or dry weight) to biomass are used to estimate the forest biomass and account for the carbon budget on a national and regional scale. This study estimated the biomass conversion and expansion factors (BCEF), root to shoot ratio (R), biomass expansion factors (BEF) and ecosystem biomass expansion factor (EBEF) of Korean pine (Pinus koraiensis) forests based on direct field surveys and publications in Korea. The mean BCEF, BEF, and R was 0.6438 Mg $m^{-3}$ (n = 7, SD = 0.1286), 1.6380 (n = 27, SD = 0.1830), and 0.2653 (n = 14, SD = 0.0698), respectively. The mean EBEF, which is a simple method for estimating the understory biomass in Korean pine forest ecosystems, was 1.0218 (n = 6, SD = 0.0090). The values of the biomass expansion factors in this study estimated the Korean pine forest biomass with more precision than the default values given by the IPCC (2003, 2006).

• Journal of Korean Society of Forest Science
• /
• v.99 no.3
• /
• pp.397-403
• /
• 2010

This study was conducted to investigate the changes in soil temperature, soil moisture content, light availability (photosynthetically active radiation, PAR) and diameter growth in 46-year-old Korean pine (Pinus koraiensis Siebold et Zuccarini) plantation located in Gwangneung experimental forest after 4 years from thinning. Three different thinning intensities [control, 45%(T45), and 60%(T60) basal area reduction] were applied in 2004. Mean soil temperature and soil water content were $8.9^{\circ}C$ and 14.3% for control, $10^{\circ}C$ and 16.1% for T45 and $10.2^{\circ}C$ and 16.1% for T60, respectively. Mean soil temperature and moisture content were significantly different among the treatment plots (p<0.05). Mean PAR in control, T45 and T60 was 44, 143 and178 ${\mu}mol/m^2$/sec, respectively and the differences were also statistically significant among the treatment plots (p<0.05). Mean annual diameter growth in control, T45 and T60 was 0.4, 1.5 and 1.2 mm, respectively. Diameter growth of Pinus koraiensis was steadily increased after thinning in comparison to control. Consequently, the results suggested that soil temperature, soil moisture content and light availability were likely to last beyond the 4 years after thinning in this Korean pine plantation.

• Journal of Ecology and Environment
• /
• v.46 no.1
• /
• pp.85-98
• /
• 2022

Background: Korean white pine (Pinus koraiensis) is a major commercial species, and the importance of the oak trees (Quercus spp.) is increasing due to various factors such as environmental and ecological values. However, more information is required to clearly understand the growth characteristics of these species especially regarding thinning intensity. This study was performed to provide the basic information to develop the silvicultural guideline and field manual by analyzing tree and stand characteristics in line with thinning intensity in the Korean white pine plantation and oak-dominated natural deciduous forest. Results: Diameter at breast height (DBH) and volume changes by the thinning intensity in the Korean white pine plantation were significantly different from those in the oak-dominated deciduous natural forest. In particular, DBH distribution in the pine stand appeared that there were more large diameter trees as the thinning intensity was higher. DBH periodic annual increment (PAI) of the pine stand was higher as the thinning intensity was stronger and the growth period was shorter. This trend was similarly shown in the natural deciduous forest, but the amount of PAI was smaller than in pine stand. The volume PAI after thinning was not decreased over time. In each stand type, the PAI tended to be lower as stand density was higher. The volume PAI in the pine stand was significantly higher than that in the oak-dominated natural deciduous forest. Dead trees occurred the most in the unthinned plots of each stand type, and those were higher in the natural deciduous forest. Ingrowth trees were observed only in the natural deciduous forest, and its distribution was the lowest in unthinned plots; Korean white pine as ingrowth occurred the most frequently among many tree species. Conclusions: Different effects of thinning treatment on DBH and volume PAI, mortality, and ingrowth were observed for each stand. With respect to forest growth, Korean white pine plantation was superior to the oak-dominated natural deciduous forest. The results of this study offer fundamental information for the development of silvicultural guidelines for Korean white pine plantations and oak-dominated natural deciduous forests in Korea.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.3 no.1
• /
• pp.1-4
• /
• 2001

This study on leaching and adsorption in Korean pine (Pinus koraiensix) to precipitation was carried out to investigate the stemflow of Korean pine and artificial crown for the concentration of leaching and adsorption of Korean pine. For comparative, we made artificial crown with plastics. The size of artificial crown was made similar with projected area of Korean pine at Kyung Hee University experimental forest, Gwangiu-gun, Kyunggi-do. In case of the concentration of leaching, the cation of $K^{+}$ was increased in November, and during the period of research, the cation of $K^{+}$ was more leached than any other dissolved element. In case of the concentration of adsorption, the cation of $Ca^{2+}$ was increased in June, July and November, and the cation of $Mg^{2+}$ and $Al^{3+}$ were increased in November.ember.

• Preventive Nutrition and Food Science
• /
• v.15 no.1
• /
• pp.36-43
• /
• 2010

The purpose of this study was to investigate the phenolic acid, proanthocyanidin (PAs), and flavonol glycoside contents, as well as the antioxidant activities of pine needle extracts from six species of young pine trees. The extracts were prepared from Section Pinus (Diploxylon): P. densiflora, P. sylvestris, P. pinaster and P. pinea, and Section Strobus (Haploxylon): P. koraiensis and P. strobus. Phenolics were extracted from pine needles with 80% acetone to obtain the soluble free fraction, and insoluble residues were digested with 4 M NaOH to obtain bound ethyl acetate and bound water fractions. Phenolics were analyzed by HPLC, and the hydrophilic antioxidant activity was measured using oxygen radical absorbance capacity (ORAC). Total phenolic and flavonoid contents of the soluble free fraction were higher than those of the bound ethyl acetate and bound water fractions. The main phenolics were monomers and polymers of PAs in the soluble free fraction, and phenolic acids and flavonol glycosides in bound ethyl acetate fraction. Flavonol glycosides found in different species of pine needles were qualitatively similar within fractions, but composition varied among Pinus sections. High levels of kaempferol arabinoside and an unknown compound were present in all Strobus species. The soluble free fraction had the highest antioxidant activity, followed by bound ethyl acetate and bound water fractions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.9
• /
• pp.1342-1348
• /
• 2014

Seeds of Korean pine cone (Pinus koraiensis) have long been consumed as an edible food in countries located in North-East Asia, On the other hand, Korean pine cone, containing various polyphenols, is discarded as a useless garbage after removing seeds. This study investigated the lipolytic effects of pine cone extract in differentiated 3T3-L1 adipocytes. Intracellular lipid accumulation was measured by Oil red O staining, free glycerol release by colorimetric reaction, and expression of genes related to lipid metabolism by real-time PCR. Compared to control, pine cone extract reduced intracellular lipid accumulation by 8.8% and increased free glycerol release by 8.2% a concentration of $5{\mu}g/mL$ in differentiated 3T3-L1 adipocytes. mRNA levels of fatty acid synthesis were not significantly different between control and pine cone extract, but mRNA levels of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) significantly increased by 38.7% and 94.1% at a concentration of $5{\mu}g/mL$, respectively. Thus, pine cone extract is suggested to have lipolytic effects through induction of LPL and HSL gene expression.

• Journal of the Korea Furniture Society
• /
• v.19 no.6
• /
• pp.460-465
• /
• 2008

When wood is exposed to natural weathering and UV radiation discoloration progresses. The color variation of heat-treated wood was investigated. Four domestic species were selected and heat-treated at $220^{\circ}C$ and naturally weathered for 42 days. Their colors were measured with a portable colorimeter. The color variations were different between species. The Korean red pine specimens were highly discolored by the natural weathering even though they were heat-treated. In contrast to Korean red pine, Korean pine is less discolored. The maximum color difference of larch was lower than Korean red pine. All specimens of birch exceeded the color difference criterion of 15 after 25 hours with the maximum of 28.

• Korean Journal Plant Pathology
• /
• v.10 no.4
• /
• pp.261-269
• /
• 1994

One hundred and ninety two isolates of Armillaria were obtained from mycelial fans on infected hosts, rhizomorphs, and single basidiospores or trauma tissue of fruiting bodies. Mating tests showed that two of these isolates were A. mellea, eight were A. tabescens, 20 were A. ostoyae, and 162 were A. gallica. Armillaria ostoyae was mainly isolated from Pinus koraiensis and Qurecus spp., A. tabescens from fruiting bodies on Pinus densiflora and Qurecus spp., and A. gallica from many tree species but not Pinus koraiensis. Armillaria mellea, A. gallica, A. ostoyae and A. tabescens showed distinct protein banding patterns. Mycelial growth and rhizomorph formation was good on basal medium with ethanol added. A. gallica and A. mellea formed many rhizomorphs, but A. ostoyae did not. A. gallica showed the best rhizomorph formation on media with tannic acid and ethanol, but a. mellea formed the most rhizomorphs on gallic acid. Rhizomorphs showed monopodial branching for A. gallica and dichotomous branching for A. ostoyae. Fruiting bodies. formed in the laboratory on sawdust media most abundantly by A. tabescens. In nature, fruit body formation by A. tabescens was from early to mid August. A. ostoyae and A. gallica fruit bodies were formed from early August to late October. While there are common names in Korea for A. mellea and A. tabescens, such as mulberry mushroom relative, no common names are available for A. gallica and A. ostoyae. Therefore, we refer to a. gallica as the Gastrodia mushroom because it has been used to produce Gastrodia and A. ostoyae as the Korean pine mushroom because it is frequently found as mushrooms on Korean pine.

• The Korean Journal of Ecology
• /
• v.8 no.4
• /
• pp.197-200
• /
• 1985

The relations of crown width and DBH for Pinus densiflora, Pinus rigida, Pinus koraiensis, and Ginkgo biloba were accomplished to estimate the level of crown competition. Measurements of the relations revealed that crown width and DBH were highly correlated for the same species. Also it seems that these relations are independent of age and site quality. The results of regression analysis were as follow: P. densiflora, Y=0.3477X+0.3828 r=0.95 p. rigida, Y=0.3537X+0.1645 r=0.95 P. koraiensis, Y=0.2895X+0.6310 r=0.92 G. biloba, Y=0.4360X+0.0995 r=0.90 The significant differences between G. biloba and pine species seems due to their structural differences of crown formation according to tree species. As results of computing Maximum Crown Area and Crown Competition Factor as indices of crown competition, they indicated that P. densiflora would grow better under the natural conditions.