• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.402-411
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• 2018

This study was conducted to develop ingrowth estimation equations on Pinus densiflora found in Gangwon Province and in the center of Korean Peninsula, based on the National Forest Inventory (NFI)'s permanent sampling plot data. For this study, identical sampling plots in $5^{th}$ and $6^{th}$ NFI data were collected in order to identify ingrowth amounts for the last 5 years. Following two-stage approaches in developing the ingrowth estimation equations, the logistic regression model was used in the first stage to estimate the ingrowth probability. In the second stage, regression analysis on sampling plots with ingrowth occurrence was used to estimate the ingrowth amount. A candidate model was finally selected as an optimal model after a verification based on three evaluation statistics which include mean difference (MD), standard deviation of difference (SDD) and standard error of difference (SED). In results, a logistic regression model based on the number of sampling plot which did not result in ingrowth (model VI), was selected for an ingrowth probability estimation equation and exponential function including the species composition (SC) variable was optimal for an ingrowth estimation equation (model VII). The ingrowth estimation equations developed in this study also evaluated the estimation ability in various forest stand conditions, and no particular issue in fitness or applicability was observed.

• Korean Journal of Breeding Science
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• v.43 no.4
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• pp.330-336
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• 2011

A comparative study was conducted on genetic correlation between 12 open-pollinated families (32-year-old) and their one-year-old seedlings for early selection on the fast-growing trait in Pinus densiflora S. et Z.. Those twelve families were divided into three groups such as superior, intermediate, and inferior, on the base of the growth indexes of 32-year-old P. densiflora. The growth performance of the 32-year-old P. densiflora showed significant correlation with the growth traits of their one-year-old seedlings. Dry weights of the seedlings had significant correlation (P < 0.01) with the growth index of the adult plants and its $R^2$ value was 0.597, suggesting that 59.7% of the families could be selected by using dry weights of one-year-old seedlings. Furthermore, the growth rates of seedling heights for superior, intermediate, and inferior groups were 4.568, 3.773, and 3.535, respectively, resulting that seedlings of the superior group grew approximately 1.3-fold faster than those of the inferior group. Therefore, we concluded that two growth traits of one-year-old seedlings dry weight and growth rate were suppose to the early selection factors for the fast-growing trait for P. densiflora.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.189-197
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• 2021

This study aims to optimize the appropriate concentration of fertilizers for Sageretia thea by analyzing growth performances (height and root collar diameter) and physiological characteristics (photosynthesis, chlorophyll contents, and chlorophyll fluorescence reaction). As fertilizer concentration was increased to 1.5 g·L^-1, growth increased, but it decreased at 2.0 g·L^-1 treatment. Root collar diameter growth was reduced because of higher fertilizer concentrations. Photosynthesis reactions showed the highest CO₂ reaction curves, maximum photosynthesis rate, and maximum carboxylation rate in the 1.5 g·L^-1 fertilizer treatment. The chlorophyll fluorescence reaction and SPAD values revealed that fertilizer treatment improves photosynthesis efficiency and robustness compared with untreated control. Therefore, the appropriate fertilizer concentration for producing good seedling quality of Sageretia thea is 1.0~1.5 g·L^-1.

• Journal of Korean Society of Forest Science
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• v.113 no.3
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• pp.319-326
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• 2024

We evaluated the impact of temperature and salinity on the germination of true mangrove Sonneratia caseolaris (L.) Engl. seeds to determine the optimal conditions for their growth. Seeds were collected from Nam Dinh Province, Vietnam. The seeds underwent temperature treatments (19℃, 24℃, 30℃, and 38℃) and salinity treatments (0‰, 10‰, 20‰, 25‰, 30‰, 35‰, and 40‰). The analysis of germination characteristics and radicle growth indicated that, under the 30℃ condition, the germination rate was 88%, and the radicle growth was 25.24 mm, showing significantly higher germination rates GR), mean germination time (MGT), and germination performance index (GPI) than under other temperature conditions (P<0.05). In the 10‰ salinity treatment group, both the germination rate (88%) and radicle growth (39 mm) were significantly higher (P<0.05). High temperatures and salinity were not suitable for seed germination, and they significantly affected seed germination and early growth.

• Journal of Climate Change Research
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• v.5 no.2
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• pp.127-137
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• 2014

The main purpose of this study is to estimate tradial growth response and to predict the potential spatial distribution of major tree species(Pinus densiflora, Quercus mongolica, Quercus spp., Castanea crenata and Larix kaempferi) in South Korea, considering climate and topographic factors. To estimate radial growth response, $5^{th}$ National Forest Inventory data, Topographic Wetness Index (TWI) and climatic data such as temperature and precipitation were used. Also, to predict the potential spatial distribution of major tree species, RCP 8.5 Scenario was applied. By our analysis, it was found that the rising temperature would have negative impacts on radial growth of Pinus densiflora, Castanea crenata and Larix kaempferi, and positive impacts on that of Quercus mongolica, Quercus spp.. Incremental precipitation would have positive effects on radial growth of Pinus densiflora and Quercus mongolica. When radial growth response considered by RCP 8.5 scenario, it was found that the radial growth of Pinus densiflora, Castanea crenata and Larix kaempferi would be more vulnerable than that of Quercus mongolica and Quercus spp. to temperature. According to the climate change scenario, Quercus spp. including Quercus mongolica would be expected to have greater abundance than its present status in South Korea. The result of this study would be helpful for understanding the impact of climatic factors on tree growth and for predicting the distribution of major tree species by climate change in South Korea.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.26-33
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• 2005

The study was carried out to provide information about growth and ecological characteristics by site types of natural deciduous forest in Pyeongchang, Gangwon Province. The data were collected from four aspects(the East, the West, the South, and the North) with three elevation(higher than 1.000 m, 700~1,000 m, lower than 700 m) and three topographical conditions(ridge, hill, and valley). Growth parameters by site types were evaluated based on the growth performances of dbh for the last 5 to 10 years; which were also estimated based on both Pressler and Schneider formulae. In addition, ecological characteristics such as Shannon-Wiener's diversity index, evenness index and richness index were analyzed by site types. The management methods by site types were suggested by considering stand density, growth patterns, and ecological characteristics. It was found that the stands on the South and the East are necessary the tending practices to improve growth and ecological characteristics. On the other hand, the West and the North needed the tending practices focusing on stand density management to increase growth rate rather than ecological management. It was also found that the area lower than 700 m in elevation showed Higher growth rate than other areas. As a management standard considered in terms of growth rate, it was suggested that tending practices should be applied to the stands of which growth rate for the last 5 to 10 years were lower than 2%. Considering topographical conditions, valley area showed better ecological characteristics than both ridge and hilly areas. Consequently, it was revealed that the valley areas were suitable for the ecological management.

• Korean Journal of Plant Resources
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• v.32 no.1
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• pp.9-18
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• 2019

This study was carried out to investigate characteristics of growth and active compounds of Angelica gigas population distributed in Mt. Jeombong. Quadrates were established in native area to harvest root part of Angelica gigas and analyze soil properties in September and October 2017. It was found that Angelica gigas populations were collected above the altitude 758 m near the valley covered with Fraxinus mandshurica and Acer pictum, and so on. In case of soil nutrient, soil organic matter, available phosphorous, and total nitrogen ranged 5.8-25.2%, 23.0-67.9 mg/kg and 0.3-1.3% respectively. Also, the Fresh weight of root ranged 28.8-65.3 g in September and 22.3-75.6 g in October. The content of active compounds ranged 2.7-4.7% in decursin and 2.9-4.5% decursinol angelate in October that was increased by 1% and 2.4% respectively compared with that in September. In the final analysis, there was positive correlation between fresh weight of root and exchangeable cation (natrium, calcium, magnesium). Also, there was positive correlation between active compounds and the content of water in root part of Angelica gigas.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.487-495
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• 2021

Lentinula edodes is a tetrapolar basidiomycete and its mating type is determined by two unlinked genetic loci, A and B. Theoretically, one dikaryotic strain could produce basidiospores with four different mating types in a 1:1:1:1 ratio. Previous studies have described the skewed segregation ratio of mating types among basidiospores of L. edodes. However, they were based only on morphological characteristics, such as clamp connection, to determine mating types. To clarify whether the segregation distortion of mating types is a general phenomenon in L. edodes, we analyzed the mating types of basidiospores obtained from three cultivars of L. edodes using recently developed DNA markers. We found that the skewed segregation of mating types was strain-specific, as reported previously. Among the three cultivars, one cultivar showed balanced segregation, while the other two displayed distorted segregation. We also examined the relationship between mating type and mycelial growth rate of monokaryons derived from each basidiospore. It was found that the monokaryotic mycelial growth rate was related to the A mating type but not to the B mating type. Therefore, homeodomain transcription factor genes that reside on the A locus or other genes linked to the A locus affect the growth rate of monokaryotic mycelia. Considering the importance of mating types in mushroom breeding, this study is informative for establishing an efficient breeding strategy as well as for understanding the mechanism of monokaryotic mycelial growth.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.667-674
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• 2022

This study was conducted to determine the three main factors [rooting time, plant growth regulators (PGRs), rooting medium] of cuttage for mass production of Sageretia thea. The experiment was observed on cuttage tray after 120 days and classified by rooting times, plant growth regulators, rooting medium. Materials were collected from natural habitats of S. thea from the Korean peninsula at March, July and September during 2019. As a result of the experiment, rooting times were showed statistically significant differences. March group's rooting rate and root length were 15 and 200% better than others. In PGRs experiment by concentration, There was no significant correlation between the control and experiment in terms of rooting rate. However, In the case of root length, IBA 500 mg/L, IBA 250 mg/L and IAA 1,000 mg/L groups were lengthened up to 170% compared to the control group, confirming statistically significant differences. As a result, we recommend treating cuttings with IBA 500 mg/L in March with Hardwood cutting.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.263-274
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• 2022

Lentinula edodes is an important commercial mushroom and there have been several reports of viral infections in L. edodes. Two mycoviruses (LeV-HKB and LeNSRV1) were detected in Sanbaekhyang (NIFoS 2778) and Taehyanggo (NIFoS 4317), the sawdust-cultivated commercial strains. The vertical transmission rates of the viruses were investigated by detecting the viruses in 80 monokaryotic strains derived from basidiospores isolated from the fruiting bodies of each strain. Most of the monokaryotic strains were infected with the virus and the two viruses showed different levels of meiotic stability, with LeV-HKB showing higher meiotic stability than LeNSRV1. Therefore, it seems that the vertical transmission mechanism of mycoviruses is different depending on the virus species. We also examined the mycelial growth rate of the monokaryotic strains and compared the growth rate according to virus infection status. Although there was no statistically significant correlation between viral infection and mycelial growth rate, we found that the average growth rate was reduced by additional virus infection. We expect our data to contribute to a greater understanding of the mechanism of the vertical transmission of mycoviruses, and promoting breeding using virus-free monokaryotic strains.