• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.24-29
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• 1997

This study was conducted to evaluate the effect of locations and nursing days on the cstablishment and the first-year growth of Aster scaber seedlings in mountainous areas. Survival rates of the seedlings ranged from 72% in Bukbang to 27% in Mt. Yeonyup B. Survival rate of 90 days-seedlings was 65%. 150days-and 120days- seedling had 2 or 3 leaves but it was almost same as that of native plants. The plants grown in Mt. Yeonyup A averaged 10.7cm high and 90 days-seedlings grew best. Dry weight of plants grown from 120 days- and 90days- seedlings was respectively 215mg and 205mg.

• Journal of Korean Society of Forest Science
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• v.89 no.4
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• pp.513-521
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• 2000

Red alder (Alnus rubra Bong.) seedlings inoculated with Frankia pure cultures were grown in a walk-in growth chamber for sixteen weeks. Half were inoculated with the spores of the ectomycorrhizal fungus Alpova diplophloeus (Zeller & Dodge) Trappe & Smith. The mycorrhizal seedlings were significantly larger than nonmycorrhizal plants in diameter, and nodule and shoot dry weight by 6 to 16% when their heights were very similar. The mycorrhizal effects on water relations of red alder seedlings were explored in a 30 hours water stress. Mycorrhizal and nonmycorrhizal seedlings did not significantly differ in leaf water potentials, $CO_2$ exchange rates or $N_2$-fixation rates during the drought. Our results suggests that A. diplophloeus mycorrhizas increased red alder seedling growth under well-watered conditions but do not affect water relations of the plant under water-stress.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.213-217
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• 1999

Seed coating and pelleting techniques have been used in many crops to improve the germination vigor of tiny and light seeds. Cultivated Chinese-foxglove (Rehmannia glutlnosa) has been infected by various types of virus derived from vagetative propagation of rootstock. Seed characteristics and alginate-coated seed germination rate have been investigated to get basic information for healthy seedling production through seed propagation. Chinese-foxglove showed different numbers of seeds per pod from 61 in Seocheon local to 207 in Jiwhang 1 and 1,000grain weight also varied from 70mg of Seocheon local to 130mg of Jiwhang 1. Seeds of Chinese-foxglove has dormancy because that seed collected last year more stimulated than that of this year at germination test. Optimum alginate concentration for pellected seeds germination was 2%.

• Korean Journal of Weed Science
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• v.11 no.3
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• pp.211-218
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• 1991

The allelopathic potentials of several Korean weeds were inverstigated in the greenhouse and laboratory. Aqueouse extracts and plant litters of several weeds were tested at different dilutions for allelopathic effect on germination and Barley growth of crop species. Among the several species of weeds. Portulaca oleracea and Chenopodium album had the highest allelopathic effect to the four species to 30%, while the extract of Portulaca oleracea increased those to 4.7% on an average when compare with control plant. In greenhouse experiment Portulaca oleracea highly reduced the emergence rate indices of barley, soybean. radish and corn to 30, 49, 36 and 68% that of control plant, respectively. Plant height and dry weight of indicate plants were reduced by the residues of Portulaca oleracea and Chenopodium album.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.209-214
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• 2006

Three lipoxygenase isozymes in soybean seeds are thought to be a major contributor to lipid peroxidation and generation of free radicals which may result in seed deterioration. This study was conducted to get the basic information for changing lipoxygenase activity during seed germination in lipoxygenase-lacking soybeans. Fresh weight of soybean seedling of Jinpumkong 2 and Taekwangkong increased more rapidly than that of Jinpumkong. Hypocotyls of Jinpumkong and Jinpumkong 2 were longer and thicker than that of Taekwangkong. Type I lipoxygenase activity (pH 9.0) in cotyledon of Jinpumkong lacking lipoxygenase-2, 3 showed higher than that of Taekwangkong, and Type I lipoxygenase activity of two cultivars decreased continually. On the other hand, Type II lipoxygenase activity of Taekwangkong began to increase continually two days after germination, reached to the maximum between 4 days and 5 days, and began to decrease continually five days after germination. Type I and II lipoxygenase activity in hypocotyls was not detected in all soybean cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.235-239
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• 1993

To determine the optimal application level of fertilizers, nitrogen, phosphate, potassium and lime in ramie(Beohmeria nivia Hooker et Arnot), the experiments were conducted for four years from seedling stage propagated by suckers to fully-grown stage under various comibinations of $N, P_2O_5, O$ and lime. Increasing in application rate of N and $K_2$O enhanced stem growth of ramie greatly, and it appeared that lime application also had large effect on increase of stem growth. Yield increased greatly by increasing of application rate with two or three times in N and two times in $K_2$O as much as the standard application rate of fertilizers N-$P_2O_5$-$K_2$O =9-3-9kg/l0a. Especially, treatment with 18kg N, 3kg $P_2O_5, $, 18kg $K_2$O and 200kg lime per l0a showed higher percentage of productive culm and increased yield of crude fiber about 33%. The variation among treatments was relatively small in stem length but larger in fresh weight of shoot and stem. The variation was large at early stage of experiment, that is, from one to two years after planting, but decreased progressively from three years after planting. There was no large difference in number of stems among application rates of fertilizers from three years after planting which was fully-grown stage. However, increasing in application rate of Nand $K_2$O twice as much as the standard rate had large effect on increasing the percentage of productive culm, and hence increased yield greatly.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.411-420
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• 2003

Physical and cultural properties were investigated on the rice-seed pellets made by the pelleting machine(Yu, 2003) as the changes with mixing ratios of soil to rice seed of 6 : 1, 7 : 1, and 8 : I, and rotating speeds of forming rolls of 7, 10, and 13 rpm. Average weight, average diameter, and average sphericity of the pellets were 1.70 g, 12.0 ㎜, and 99.1 ％, respectively. Average number of seeds per pellet was more than 3, and almost all pellets had more than 3 seeds in the cases of mixing ratios of 6 : 1, and 7 : 1 at the forming rolls' speed of 7 rpm. Gradual drying was needed because rapid drying caused cracks on surface of the pellets. Compression strength of the pellets dried in shady room was in the range of 132 ∼ 152 N, which was enough for handling. Comparing with the previous pellets(Park, 2002), average number of seeds per pellet, ratio of pellets including more than 3 seeds, and compression strength increased due to the effects of pressure feed of pellet materials, and improvements of the forming rolls. Emergence ratio of the pellets made at the mixing ratio of 6 : 1 and the forming rolls' speed of 7 rpm, was 100 % on dry paddy and was 97 % on flooded paddy surface. Good growth characteristics, and yield except number of seedling stand and ratio of missing plant were shown in planting of the pellets made at the mixing ratio of 7 : 1 and the forming rolls' speed of 7 rpm on flooded paddy surface field. Considering the cultural results, the mixing ratio of 6 : 1, and the forming rolls' speed of 7 rpm seems to be optimum operating condition for the improved pelleting machine.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.335-340
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• 1998

This study was conducted to determine the morphological responses of barley seedlings to NaCl stress and to investigate histological changes of cells with transmission electron microscope(TEM) after NaCl stress. Plant height and root length of 10-day old barley seedlings with NaCl stress were reduced and inhibition level was found to be more severe in the plant height than in the root length. The leaf length, leaf width and leaf area were shorter as well with NaCl stress than without NaCl stress. However, there was no difference in the number of roots between NaCl treatments. The weight of dry matter decreased at higher NaCl concentrations, especially at 100mM NaCl. The water content of shoots tend to decrease at higher NaCl concentrations, but there was no difference in the water content of roots, The reduced sugar content was greatly increase than starch. Cellulose content was higher in NaCl stressed-plant than control, and tended to decreased at higher NaCl concentrations. Lignin content also decreased NaCl stressed-plant but there was no tendency at NaCl stress concentrations. Electric conductivity of cell sap with seedlings was high with NaCl stressed-plant. Amount of cell sap gradually increased with time in the roots than in the shoots, The grana of chloroplasts was changed by 150mM NaCl concentration. The christe of mitochondria in root meristematic sells ruined in structure and cell wall of leaf and root was also ruined by NaCl stress.

• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1527-1535
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• 2018

Bacterial strain BAS23 was isolated from rice field soil and identified as Bacillus amyloliquefaciens. Based on dual culture method results, the bacterium BAS23 exhibited potent in vitro inhibitory activity on mycelial growth against a broad range of dirty panicle fungal pathogens of rice (Curvularia lunata, Fusarium semitectum and Helminthosporium oryzae). Cell-free culture of BAS23 displayed a significant effect on germ tube elongation and mycelial growth. The highest dry weight reduction (%) values of C. lunata, H. oryzae and F. semitectum were 92.7%, 75.7%, and 68.9%, respectively. Analysis of electrospray ionization-mass spectrometry (ESI-MS) and $^1H$ nuclear magnetic resonance (NMR) spectroscopy revealed that the lipopeptides were iturin A with a C14 side chain (C14 iturinic acid), and a C15 side chain (C15 iturinic acid), which were produced by BAS23 when it was cultured in nutrient broth (NB) for 72 h at $30^{\circ}C$. BAS23, the efficient antagonistic bacterium, also possessed in vitro multiple traits for plant growth promotion and improved rice seedling growth. The results indicated that BAS23 represents a useful option either for biocontrol or as a plant growth-promoting agent.

• Journal of Bio-Environment Control
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• v.13 no.2
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• pp.81-89
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• 2004

This study was conducted in a commercial plug glasshouse in Sacheon to examine the possibility of producing tomato plug seedlings using various growing media containing cellular glass foam (CGF)and carbonized chestnut woodchips (CCW) as medium components. Plug seedlings of 'Seogun' tomato were grown in media containing 50% CCW＋50% peatmoss, 33% CGF＋67% peatmoss, and 50% peatmoss＋50% granular rockwool. A commercial plug medium (Tosilee) was used as the control. All seeds were sown in 200 cell plug trays on November 28, 2001. Seedling growth was measured at 31 days after sowing. Each treatment showed a similar growth result as compared to the control. Plant height, root grade, fresh weight, and air space and bulk density of the medium were significantly greater in the 33% CGF＋67% peatmoss treatment than those in the other media. However, growth was slightly suppressed in the 50% CCW＋50% peatmoss. pH and EC of the media were the highest in the control treatment, although no toxicity symptoms had been observed. The results suggest that perlite can be replaced with a new material such as CGF in the commercial scale production of plug seedlings of 'Seogun' tomato.