• Journal of Korean Society of Forest Science
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• v.55 no.1
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• pp.22-29
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• 1982

Two ectomycorrhizal fungi, Pisolithus tinctorius and Thelephora terrestris, were introduced form U.S.A. and inoculated to five pine species in Korea to evaluate the reported growth stimulation of host plants after inoculation. These fungi were grown as mycelial inoculum in large quantity and ioculated to the fumigated nursery soil just before seed sowing. At the end of the first growing season. Pisolithus stimulated the height growth of Pinus densiflora. P. thunbergii. P. rigida, and P. rigida x teada by55, 36, 69, and 37%, respectively, compared with control seedlings with no fumigation and no inoculation. When the growth stimulation was expressed with dry weight, Pisolithus increased dry weight of P. densiflora and P. rigida x taeda by 143% and 128%, respectively, over control seedling. Thelephora failed to stimulate growth of inoculated plants. Pinus koraiensis did not respond to the inoculation during the first growing season. It is concluded that artificial inoculation of nursery pine trees with selected mycorrhizal fungi should be seriously considered to improve the quality of planting stocks and to stimulate early plant growth. The potential for use of Pisolithus in reforestation on adverse sited is also discussed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.72-85
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• 2003

The purpose of this study is to establish the basis of the ecological restoration on the limestone mines in Korea, through the research of the revegetation measures of the disturbed slopes in Japanese limestone mines and the analysis of the case of Ibuki and Bukou limestone mines to realize the restoration works successfully. According to the number of mines to carry out the revegetation works increase every year, the revegetation area and amount of planting also go on increasing in Japan. In the small mines the environmental problem is not recognized seriously, but some mines have muchly invested in the revegetation of the damaged land by mines. Ibuki mine in Shiga-gen is practicing the four principles for the restoring of the revegetation in the disturbed slopes by mines. Firstly, the mean slope preserves $37^{\circ}$ in the last rock cut slopes. Secondly, the last rock cut slopes to rehabilitate are covered with the soil dressing 30cm high. Thirdly, the grasses in the mining area are digged up beforehand, and then they are reused to the revegetation works of rock cut slopes. Lastly, from the upper rock cut slopes the revegetation works begin, the process of the above are repeated, as the result, the restoring works will be completed. Upon the ground of these principles, the complex of the original vegetation and the native species seeding, that is, the revegetation technique of Ibuki have established. In the difficult area to revegetate, sodding works, heaping up vegetation-sack, seed-spraying, heaping up soil-sacks and planting works are adapted variously. Bukou mine in Saitama-gen try to maintain the revegetation, the screening and the stability of the enormous mining rock cut slope, and for these works, the activity of 'Chichibu Working Group of Rock Wall for Limestone Mines' contributes largely. The chief technique of the revegetation in Bukou mine is following; after the making the berm on the rock cut slopes, the soil dressing is filled in it, and the trees is planted for the screening of the rock cut slopes. They devide the rock cut slopes into four typical types, and choose the different ways to make the berm and fill the soil dressing in characteristic. Most of the planting trees are consist ofthe native species of Mt. Bukou through the stages of the nursery and transplantation. Not only the revegetation of the demaged land but also the breeding of the conservational plants also are their important business.

• Journal of Korea Foresty Energy
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• v.21 no.3
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• pp.46-53
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• 2002

The study was carried out to determine the growth and biomass production of deciduous trees including Betula pendula, Fraxinus rhynchophylla, Cornus controversa subjected to artificial shade treatment of three levels in nursery field. The results were as follows; The height growth of seedlings was no difference subjected to artificial shade treatment. The root collar diameters of the relative growth rates of seedlings grown in full sun showed 29-32% as compared with those subjected to the shade treatment of 7-10% light intensities of full sun. Corrus controversa of the root collar diameters of the relative growth rates were better in the seedlings grown in 26-34% light intensities of full sun. Total dry mass including the dry mass of leaves, shoot and root were as a whole decreased with shade treatment. The ratio of the dry mass of leaves and stem increased the dry mass of root. T/R ratio of the seedlings increased by decreasing the relative light intensity. And the T/R ratio of 7-10% light intensities of full sun was ranged from 1.00~2.27 were greater in the full sun light was ranged from 0.51~l.13. Light intensity by artificial shade treatment decreased in deciduous trees when compared on the whole, it showed tendency that SLA increases, increased that seeing resemblant tendency in LAR and LWR and changed of light intensity is strong, it increased that showed difference as statistical.

• The Plant Pathology Journal
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• v.32 no.5
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• pp.441-451
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• 2016

Deep sequencing has generated 52 contigs derived from five viruses; Apple chlorotic leaf spot virus (ACLSV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV), Apple green crinkle associated virus (AGCaV), and Apricot latent virus (ApLV) were identified from eight apple samples showing small leaves and/or growth retardation. Nucleotide (nt) sequence identity of the assembled contigs was from 68% to 99% compared to the reference sequences of the five respective viral genomes. Sequences of ASPV and ASGV were the most abundantly represented by the 52 contigs assembled. The presence of the five viruses in the samples was confirmed by RT-PCR using specific primers based on the sequences of each assembled contig. All five viruses were detected in three of the samples, whereas all samples had mixed infections with at least two viruses. The most frequently detected virus was ASPV, followed by ASGV, ApLV, ACLSV, and AGCaV which were withal found in mixed infections in the tested samples. AGCaV was identified in assembled contigs ID 1012480 and 93549, which showed 82% and 78% nt sequence identity with ORF1 of AGCaV isolate Aurora-1. ApLV was identified in three assembled contigs, ID 65587, 1802365, and 116777, which showed 77%, 78%, and 76% nt sequence identity respectively with ORF1 of ApLV isolate LA2. Deep sequencing assay was shown to be a valuable and powerful tool for detection and identification of known and unknown virome in infected apple trees, here identifying ApLV and AGCaV in commercial orchards in Korea for the first time.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.47-69
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• 2011

The purpose of this study is to suggest strategies for vitalizing Jeju citrus export-specialized organization. To achieve the goal, the research has been focused on the establishment and standardization for fruit production practices that can keep a steady supply of high quality citrus fruit for export market, and followed by systematization of farms using the practices. According to the research findings, it is desirable that the high quality fruit production manual such as the Global GAP must be established, developed and prepared to train farm households. The establishment of the high quality fruit production manual is focused on the items as follows : 1) labor productivity enhancement by structural improvement of farm layout, 2) the practices for high-sugar-fruit production such as thinning out, irrigation and drainage system, and mulching with a poromeric sheet 3) productivity enhancement and quality improvement of fruit by cultivar improvement and virus-free nursery trees, 4) standardization of cultural practices throughout the citrus fruit production.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.63-71
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• 1985

To sled the superior clones of Populus alba ${\times}$ Populus glandulosa $F_1$, growth and some growth-related enzyme activities were examined for thirteen, two-year-old and fifteen, three-year-old trees at Seoul National University nursery in Suwon. Clonal differences in total dry weight per tree and leaf surface area per tree were significant at the 5% level. Significant correlations were found between total dry weight per tree and leaf surface area per tree (r=0.875), between leaf peroxidase activity per tree and total dry weight per tree (r=0.854), and between leaf nitrate reductase activity per tree arid total dry weight per tree (r=0.914). Leaf peroxidase and nitrate reductase activities per unit fresh weight of one-year-old tree increased with increasing leaf order numbers basipetally, reaching maximum values in the eighteenth and thirty-third leaves, respectively, and decreased gradually from those leaves to basipetal lower leaves. Clones 65-29-19, 66-15-3, 65-22-11, 66-14-93, and 66-26-55 among two-year-old trees, and clones 64-6-44, 66-14-29, 66-26-55, 65-22-11, and 68-1-54 among three-year-old trees showed greater leaf surface areas, peroxidase and nitrate reductase activities per unit leaf fresh weight than other clones, Growth of Populus alba ${\times}$ Populus glandulosa $F_1$ clones might be estimated from either leaf surface area per tree or peroxidase and nitrate reductase activities per tree. Therefore, measurements of leaf surface area and leaf enzyme activities appear useful to select superior Populus clones at early growth stages.

• Journal of Korea Foresty Energy
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• v.21 no.1
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• pp.65-75
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• 2002

The study was carried out to determine the growth and biomass production of major deciduous trees including Betula platyphylla var. japonica, Betula schmidtii, Zelkova serrata, Acer mono, Prunes sargentii, and Ligustrum obtusifolium subjected to artificial shade treatment in nursery field. The six deciduous trees seedlings grow for 2 years under different light intensity of 100%, 38-62%, 22-28%, 7-20%, and 2-6% of the full sun light intensity. The results were as follows; In the seedling heights and root collar diameters of shade intolerant species like Betula platyphylla var. japonica and Betula schmidtii, the relative growth rates of seedlings grown in full sun showed 2 times as compared with those subjected to the shade treatment of 2-6% light intensities of full sun. In the shade tolerant species like Acer mono ant Ligustrum obtusifolium, the growth performances were better in the seedlings grown in 38-62% light intensities of full sun. Total dry mass including the dry mass of leaves, shoot and root were as a whole decreased with shade treatment. The ratio of the dry mass of leaves and stem increased the dry mass of root. T/R ratio of the seedlings increased by decreasing the relative light intensity. And the T/R ratio of 2-6% light intensities of full sun was ranged from 1.1~5.0 were greater in the full sun light was ranged from 0.6~3.2. Light intensity by artificial shade treatment decreased in deciduous trees when compared on the whole, it showed tendency that SLA increases, increased that seeing resemblant tendency in LAR and LWR and changed of light intensity is strong, it increased that showed difference as statistical. But, LWR of Betula platyphylla var. japonica increased gradually and showed tendency that decreases rapidly in the shade treatment of 2-6% light intensities of full sun. This result is thought that biomass production decreased by shading treatment influenced in physiological characteristics such as leaf area and decrease of the leaf amount.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.329-332
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• 1999

The objective of this study was to determine the influence of grafting timing, rootstock cut timing and leaf removal with promalin ($GA_{4+7}+BA$) treatments on the maiden tree growth, lateral development and flower bud initiation. In mid-March 1997, two-year-old M.9-T337 rootstocks selected with trunk diameter over 1 cm were planted in the field. Chip budding with 'Fuji' scion on M.9-T337 rootstock budded in mid-April was earlier in sprouting than chip budding in mid-June. Late cutting chip budding (LCCB) with 'Fuji' scion on M.9-T337 rootstock was lower in the failed budding percentage with 14% than that of early cutting chip budding (ECCB). Especially, ECCB in April was not suitable for scion growth such as uniformity with high percentage of failed tree. Grafting timing in mid-June and rootstock cutting timing of LCCB induced more branches and flower buds than other treatments. Removal of 8 to 10 uppermost immature leaves on central leader stem and application of Promalin 250 mg/L after every 30 cm of terminal growth produced a 189 cm tall tree with 9 flower buds and 14.2 short lateral shoot from 30 to 35 cm long in length in 1998. Promalin increased branching on second-season growth and, when combined with leaf removal, resulted in uniform distribution of branches along the central leader stem.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.50-68
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• 1992

The results of survey on the nematodes associated with sapling from 8 Forestry Experiment Stations(F.E.S.) in Korea are reported herein. A total of 35 species under 20 genera, 11 families, and 2 orders were identified from the soils around the roots of 119 tree species and amongst them, Xiphinema insigne is unrecorded species for Korea and Geocenamus sp. is a new species. Tylenchorhynchus claytoni, which showed the highest detection rate (D.R.) from all F.E.S., except Nambu F.E.S, was the dominant species among the nematodes associated with saplings. The D.R. of T. claytoni was the highest in Ch’ungnam F.E.S. by 100% from 15 saplings sampled, followed by 87.5% in Kangwon, 66.6% in Kyongbuk, 58.3% in Cheonbuk, 48.1% in Ch’ungbuk, 41.3% in Kyongki, and 40% in Cheonnam F.E.S. Other important nematode species which showed very high densities by stations are; Criconemella morgensis (D.R.: 37.5%), Helicotylenchus digonicus (D.R. : 35%), Pararotylenchus pini (D.R.: 37%), Tylenchorhynchus nudus (D.R.: 37.9%), Criconemella informis (D.R.: 27.5%), and Meloidogyne sp. (D.R.: 12.5), from Chunbuk, Chunnam, Ch’ungbuk, Kyongki, and Kangwon F.E.S., respectively.

• Research in Plant Disease
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• v.22 no.3
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• pp.158-167
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• 2016

A pathogen that causes a new disease on green pumpkin in the nursery and the field was characterized and identified. Symptoms of the disease on green pumpkin were water soaking lesions and spots with strong yellow halo on leaf, brown lesion on flower, and yellow spot on fruit. The bacterial isolates from the leaf spot were pathogenic on the 8 curcubitaceae crop plants, green pumpkin, figleaf gourd, wax gourd, young pumpkin, zucchini, cucumber, melon, and oriental melon, whereas they did not cause the disease on sweet pumpkin and watermelon. They were Gram-negative, rod shape with polar flagella, fluorescent on King's B agar and LOPAT group 1a by LOPAT test. Their Biolog substrate utilization patterns were similar to Pseudomonas syringae pv. syringae's in Biolog database. Phylogenetic trees with 16S rRNA gene sequences and multilocus sequence typing (MLST) with nucleotide sequences of 4 housekeeping genes, gapA, gltA, gyrB, rpoD and those of P. syringae complex strains in the Plant Associated and Environmental Microbes Database (PAMDB) showed that the green pumpkin isolates formed in the same clade with P. syringae pv. syringae strains. The clade in MLST tree was in the genomospecies 1 group. The phenotypic and genotypic characteristics suggested that the isolates from green pumpkin lesion were P. syringae pv. syringae.