• Journal of Ecology and Environment
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• v.32 no.1
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• pp.13-18
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• 2009

This study was conducted to investigate ectomycorrhizal (ECM) diversity on Pinus densiflora seedlings in a disturbed pine forest. Pine seedlings less than one year old were collected from disturbed and undisturbed sites in the Mt. Songni region. The belowground ECM fungal communities colonizing P. densiflora seedlings were studied using morphotyping and DNA sequencing. The relative abundance of ECM root tips was significantly higher in the undisturbed sites than in the disturbed sites, and the ECM species diversity was lower in the disturbed sites than in the undisturbed sites. In addition, the ECM community composition was significantly different in the disturbed and undisturbed forest sites.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.590-598
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• 2015

Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.399-408
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• 2017

Research on the rapid and accurate prediction of physical properties of wood using near-infrared (NIR) spectroscopy has attracted recent attention. In this study, partial least squares analysis was performed between NIR spectra and air-dried specific gravity of five domestic conifer species including larch (Larix kaempferi), Korean pine (Pinus koraiensis), red pine (Pinus densiflora), cedar (Cryptomeria japonica), and cypress (Chamaecyparis obtusa). Fifty different lumbers per species were purchased from the five National Forestry Cooperative Federations of Korea. The air-dried specific gravity of 100 knot- and defect-free specimens of each species was determined by NIR spectroscopy in the range of 680-2500 nm. Spectral data preprocessing including standard normal variate, detrend and forward first derivative (gap size = 8, smoothing = 8) were applied to all the NIR spectra of the specimens. Partial least squares analysis including cross-validation (five groups) was performed with the air-dried specific gravity and NIR spectra. When the performance of the regression model was expressed as $R^2$ (coefficient of determination) and root mean square error of calibration (RMSEC), $R^2$ and RMSEC were 0.63 and 0.027 for larch, 0.68 and 0.033 for Korean pine, 0.62 and 0.033 for red pine, 0.76 and 0.022 for cedar, and 0.79 and 0.027 for cypress, respectively. For the calibration model, which contained all species in this study, the $R^2$ was 0.75 and the RMSEC was 0.37.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.781-790
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• 2019

Changes in the physical and chemical properties of soil materials during the nursing process have a great influence on the quality of containerized seedlings and on growth and survival after planting. In this study, the effect of biomaterials and their mixed ratios on the growth of Zelkova serrata seedlings in a containerized seedling production system was investigated. Mushroom sawdust, pine bark, and carbonized rice husk were used as biomaterials. The mixed ratios were 10% and 20% volume ratio of the growing medium volume, including the untreated controls. There was no significant difference in the height growth of the Zelkova serrata seedlings according to the biomaterials. The root collar diameter was the highest with the 20% carbonized rice husk and the lowest with the mushroom sawdust. The difference between the highest quality index and the lowest quality index was 30% in the order of the carbonized rice husk, pine bark, control, and mushroom sawdust, but there was no statistical significance. In this study, if the growing medium mixed with biomaterials does not reduce the seedling growth compared with the control, it is considered that the biomaterial can replace a part of the growing media. Therefore, the results show that some of the growing media can be replaced with carbonized rice husk or pine bark when producing Zelkova serrata seedlings.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.4
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• pp.59-67
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• 2020

In this study, the effects of windbreak fences composed of natural vegetation on one-year-old seedlings were analyzed to develop restoration methods for an endangered subalpine species, the dwarf Siberian pine (Pinus pumila (Pall.) Regel). One-year-old seedlings were planted in 2016 by sowing seeds that had been collected from the Daecheongbong area on Mt. Seoraksan, South Korea, in 2014. The area near Daecheongbong was selected as the experimental site, and treatment and control plots (2m×2m) were installed at the site. To analyze the effects of wind protection, windbreak fences were constructed in the treatment plots using hairy Korean rhododendrons (Rhododendron mucronulatum Turcz. var. ciliatum Nakai) from the surrounding area and weather stations were installed to investigate atmospheric temperature, humidity, and wind speed. In all control plots without windbreak fences, dwarf Siberian pine seedlings were killed by strong winds seven months after planting. In contrast, the average survival rate of the seedlings in treatment plots was 96.7% after seven months, 64.2% after two years, and 45% after three years, with most (85.3%) of the seedlings showing good initial root establishment. Accordingly, windbreak fences composed of natural vegetation are suitable for promoting the early establishment of seedlings in the restoration of dwarf Siberian pine stands.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.658-667
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• 2015

This research was conducted to investigate the influence of various levels of fused superphosphate as pre-planting fertilizer on the growth of red-leaf lettuce and changes in the chemical properties of the soil solution in three root media, namely coir-dust plus expanded rice hull (8:2, v/v; CD+ERH), carbonized rice hull (6:4; CD+CRH), or ground and aged pine bark (8:2; CD+GAPB). The amounts of fused superphosphate (FSP) incorporated into the three root media during formulation were controlled from 0 to $6.0g{\cdot}L^{-1}$ in $1.5g{\cdot}L^{-1}$ increments. The root media containing fertilizers were packed into 300 mL plastic pots and seedlings of red-leaf lettuce at the 3rd leaf stage were transplanted. After transplanting, the crops were fed with a solution of neutral fertilizer ($100mg{\cdot}L^{-1}$). The growth of red-leaf lettuce was investigated 5 weeks after transplanting and soil solutions were extracted and analyzed every week for pH, EC, and concentrations of macro-nutrients. The elevation of application rates of FSP in the three root media resulted in better growth, and the crops grown in CD+ERH and CD+GRPB had greater fresh and dry weights than those in CD+CRH when compared among the treatments of equal amounts of FSP. The pH and $PO_4{^{-3}}$ concentrations in the soil solution of CD+CRH at 3 weeks after transplant were in the ranges of 4.0 to 4.8 and 20 to $100mg{\cdot}L^{-1}$, respectively. These were lower pH and higher $PO_4{^{-3}}$ concentrations than those in CD+ERH and CD+GAPB. The $K^+$ concentrations were higher in CD+CRH than those in the other two root media, and the elevation of FSP application rates resulted in higher $Ca^{+2}$, $Mg^{+2}$ and $SO_4{^{-2}}$ concentrations in soil solution of the three root media. The $NO_3$-N concentrations in soil solution rose continuously during crop cultivation, implying that the leaching percentage was elevated. The soil solution EC varied, showing the same tendencies as the $NO_3$-N concentrations. The above results indicated that the CD+ERH and CD+GRPB media performed better than CD+CRH, and optimum application rates of FSP in the three root media were 4.5 to $6.0g{\cdot}L^{-1}$ for pot cultivation of red-leaf lettuce.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.138-141
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• 1982

The insecticides aldicarb$(Temik^{(R)}\;15G)$, carbofuran$(Curaterr^{(R)}\;3G)$, and disulfoton$(Disyston^{(R)}\;5G)$ were evaluated in the field for the control of the pine gall midges(Thecodiplosis joponensis Uchida et Inouye) at rate of 5 a.i.g/cm dbh using the method of circle-furrow treatment(ca. loom in furrow depth), apart 50cm Iron the trunk of the pine trees. In addition, for improving the application method of granular insecticides the effects of conventional circle-furrow treatment were compared with those of pit treatments and radical-furrow treatments. A single root-zone treatment of aldicarb and carbofuran i the pine trees was significanlty effective for the pressure of the gall incidence by the insects. Control effectiveness in three-pit treatment was identical with those in conventional circle-furrow treatment. The pit treatment compared with the circle-furrow and radical furrow treatments would be a further feasible method in saving labor cost.

• Research in Plant Disease
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• v.18 no.2
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• pp.101-108
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• 2012

In 2006, pinewood nematode, Bursaphelenchus xylophilus, was isolated from about 50 years old trees of Pinus densiflora and P. koraiensis showing leaf-wilt and -drying symptoms in Gwangju, Gyeonggi-do and Chuncheon, Gangwon-do. Isolation of pinewood nematodes from sapwood of infected pine trees showed no difference in population density between tree species and among the sampling heights on the main stem. Migration of pinewood nematodes in the host tree were investigated by inoculation of red pine (P. densiflora, 3 years old) seedlings with B. xylophilus. The nematodes seemed to move in red pine seedlings prior to multiplication and it might have taken about 20 days to start multiplication and expression of symptoms including wilt and dieback. In initial time after inoculation, nematodes started migration through the cortical resin canal from inoculated site and further showed upward and downward movements. More nematodes were observed in cortical resin canal during early period of inoculation and later in resin canal of xylem and tracheid also while, the pith still remained free from nematode. The density of B. xylophilus was higher in seedlings of low-vigor with poor root growth than in seedlings of normal root growth. Seedlings showing high density of B. xylophilus exhibited stem discoloration and secondary infection by fungus at the inoculation site.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.66-73
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• 2004

Three species of Italian poplar (Populus euramericana), red pine (Pinus densiflora) and oriental oak (Quercus variabilis) were selected for this study. They were cut so that the distances between each of tips and roots for a pair of fingers were 0, 0.15, 0.30 and 0.45 mm. Poly vinyl acetate (PVAc) and resorcinol-phenol resin (RPR) were used for finger-jointing. Compressive test parallel to the grain was conducted for the finger-jointed specimens. The results were as follows: The efficiency of compressive Young's modulus of finger-jointed timber to solid wood indicated low values, whereas the efficiency of compressive strength indicated high values of more than 90% in all species, especially, it was found that those of red pine indicated markedly high values of more than 97%. The efficiency of compressive displacement of Italian poplar finger-jointed timber was 2 times higher than solid wood, and it was 1.2 and 1.3 times higher than solid woods in red pine and oriental oak, respectively. Also, it was found that 0, the distance between each tip and root for the fingers, indicated the highest efficiency of compressive strength performance in Italian poplar finger-jointed timber, and for red pine and oriental oak finger-jointed timbers, the distances of 0.15 and 0.30 were found to indicate the highest efficiency.

• Mycobiology
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• v.41 no.2
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• pp.77-81
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• 2013

This study aimed to investigate differences in ectomycorrhizal (ECM) fungal communities between disturbed sites and undisturbed old forest sites. ECM root tips of Pinus densiflora were collected from 4 sites disturbed by human activities and 3 undisturbed old forest sites adjacent to the disturbed sites. Results in this study showed that the number of ECM root tips, species diversity, and number of species were significantly higher in the disturbed sites than in the undisturbed sites, suggesting that the ECM fungal community structure was affected by the degree of disturbance.