• Korean Journal of Organic Agriculture
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• v.10 no.2
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• pp.111-120
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• 2002

This study was conducted to investigate the effect of foliar application of Chitosan and seedling types on increasing the production of fall-growing potatoes(Solanum tuberosum) at the height of 250m from the sea in Jeju Island. The experiment main-plots consisted of four Chitosan applications, and subplots had three seedling types as cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot. The foliar application of Chitosan of 2000ppm was carried out 0, 1, 3, 5 times at intervals of ten days after ten days of transplanting. Plant height and top dry weight were significantly more vigorous as three to five application of Chitosan. In the small tubers(under 80g), the number of tubers and tuber yield were relatively increased in the seed potatoes planting plot and mine-tuber plug seedling plot, but the large tubers(over 80g) was higher in the cutting plug seedling planting plot. T-N content in leaves was increased as the number of application of Chitosan was increased. A similar tendency was shown in K, P Ca, Mg and Na. The growth and tuber yield in cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot were effectively increased as three to five foliar applications of Chitosan was increased.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.299-306
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• 2003

This study was carried out to select superior soybean cultivars for forage production for soybean forage production in Jeju. The results obtained are summarized as follows; Eighteen soybean cultivars were grown from May 11 to September 11 in 2002 in Jeju to select superior cultivars for forage production. Days to flowering was shortest(58 days) for Seokryangkong and Keunolkong, and longest(93 days) for Danpaheukdu. Days to flowering for other cultivars ranged from 65 to 69 days. Pureunkong and Namhaekong had greater heights(129.3 and 124.6 cm, respectively) while Keunolkong, Hwaeomkong and Seokryangkong had shorter heights. The number of branches per plant was gratest for Sobaekkong, Manrikong, Pungsankong, Kwangankong and Geumgangkong. The number of leaves per plant was geatest for Sobaekkong, Iksankong and Namhaekong. Rueunkong and Jangmikong had thicker stems. Fresh forage yield was greatest for Iksankong, Sobaekkong and Namhaekong(39.5, 39.3 md 38.0 MT/ha respectively). DM yield of forage was featest for Baekunkong, Hnrunkong and Danpaheukdu. Danwonkong, Dawonkong, Seokryanfong and Pungsankong had ueatest forage crude protein content. Duyukong and Kwangankong had featest forage crude fiber content. Jangmikong and Keunolkong had feater crude fat content, while Sobaekkong and Kwangankong had greater crude ash content. Namhaekong, Seokryangkong, Keunolkong and Jinpumkong had greater NFE contents ranging 40.0 to 43.5 and TDN was featest in Keunolkong, Danpaheukdu, Namhaekong and Seokryangkong had greater NFE contents ranging from 59.8 to 60.9％. The best cultivars in Jeju for forage soybean appear to be Namhaekong, Danpaheukdu md Baehukong on the basis of crude protein, TDN, and dry matter yields.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.283-288
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• 2003

This study was carried out to a comparison of nutrient value and total digestible nutrient yield f3r select the promising barley cultivar for whole crop silage in paddy field of Suwon from 1998 to 2001. In milk stage, acid deferent fiber(ADF) content of barley were 27.3 ∼ 29.1, 27.4 ∼ 30.4 at yellow ripe stage. Neutral deferent fiber(NDF) content of milk and yellow ripe stage were 50.6 ∼ 55.9 and 53.1 ∼ 00.0. Also, total digestible nutrient(TDN) content of milk and yellow ripe stage we.e 65.4 ∼ 67.4 and 64.3 ∼ 67.7. And TDN yield at milk and yellow ripe stage were 4,120 ∼ 5,528 and 5,674 ∼ 6,569 MT per ha and in vitro dry matter digestibility(IVDMD) at milk and yellow ripe stage were 65.8 ∼ 74.6 and 64.6 ∼ 73.9. The for promising barley cultivars for whole crop silage in paddy field were Albori at Suwon. it was best before yellow ripe stage for harvest in cropping system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.151-158
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• 2003

This study was carried out to determine the effect of pig slurry applications on the forage yield of Sorghum${\times}$Sudangrass hybrid and leaching of $NO_3$-N in volcanic ash soil in Jeju. It was arranged as a randomized block design with seven treatments: chemical fertilizer ($N-P_2$$O_{5}$ $-K_2$O=200-l50-150kg/ha), pig slurry 200kg N/ha, pig slurry 300kg N/ha, pig slurry 400kg N/ha, pig slurry 100kg N/ha+chemical fertilizer 100kg N/ha, pig slurry 150kg N/ha+chemical fertilizer 100kg N/ha, pig slurry 200kg N/ha+chemical fertilizer 100kg N/ha. The mean dry matter yield of Sorghum${\times}$Sudan grass hybrid per ha for 4 years(1998 to 2001) was higher(p<0.05) in pig slurry 300kg N/ha(l7,279kg) and pig slurry 400kg N/ha(17,817kg) treatments than those of other treatments. The $NO_3$-N concentrations of leaching water at soil depth 30cm in all treatments were excess the standard of WHO with level of $10.0mg/\ell$ on 20 days of the seeding, but this $NO_3$-N concentrations found to be below $5.0mg/\ell$ on August.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.193-202
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• 2003

This study was conducted to investigate the effects of the type and application level of swine manure on herbage productivity, efficiency of nitrogen utilization and environmental pollution by the leaching of nitrogen compounds in mixed grassland. The field experiment was carried out on established grassland sward growing on silt clay loam soil. Main plots were the types of swine manure, such as swine manure fermented with sawdust(SMFWS), swine manure fermented without sawdust(SMF) and swine slurry(SS), and mineral fertilizer(Urea). Subplots were the application levels of swine manure, such as 100, 200 and 400 kgN/ha, The results obtained were summarized as follows; 1. Herbage productivity, nutritive value and nitrogen yields were the highest with mineral fertilizer and followed by swine slurry(SS), and the lowest with swine manure fermented with sawdust(SMFS). As compared with dry matter(DM) yield by application of mineral fertilizer(100%), the DM percents of SMFWS, SMFS and SS were 90.6, 80,9 and 76.8%, respectively. 2. Organic matter(OM) contents of the soil were increased by the applications of swine manure. OM contents were the high set with SMFS and the lowest with mineral fertilizer. 3. The amounts of nitrate leaching by types and application levels of swine manure were the highest in the end of Aug. and early of Sep. during the seasons and ranged from 10 to 25ppm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.290-297
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• 2013

This study was carried out to investigate the effects of a by-product feed-based silage (BF silage) feeding on behavior patterns of growing Hanwoo steers. A total of 10 Hanwoo steers (11 months old, 302kg of body weight) were assigned to 2 dietary treatments: the control (concentrate mix + free access to rice straw), and the treatment (concentrate mix + free access to BF silage). The behavior patterns were observed for 48 hours. The intakes of dry matter (DM) and neutral detergent fiber (NDF) of the treatment group were higher than those of the control group. Eating time, ruminating time and resting time were not different between the control and treatment. But, the intake time per kg DM was higher for the control than treatment. The number of bolus, total chewing frequency, number of ruminating per bolus and number of bolus per minute were not different between the control and treatment. But the chewing frequency per bolus was higher in the treatment than control (p<0.05), and feed value index was lower in treatment than control (p<0.05). Frequencies of drinking and defecating were not different between the two groups, but the frequency of urinating was higher for the treatment (p<0.05) than control. Eating rate, ruminating efficiency and chewing efficiency were much higher in the treatment group than control (p<0.05). These results indicate that the replacement of conventional rice straws with the BF silage (physically effective NDF, about 25%) did not affect the ruminating behaviors of Hanwoo steers significantly.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.247-250
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• 1998

This study was carried out to investigate the effects of changes of ionic strength according to growth stage on growth and flowering of Dendranthema grandiflorum (Ramat.) Kitamura 'Seiun' grown hydroponically in perlite. The stage I, II, and III covered early vegetative growth (27-40 days after planting), latter vegetative growth (41-54 days), and reproductive growth (55-80 days), respectively. The 2 strength (1S and 2S) of nutrient solution were treated in stage I, whereas 3 strengths (1S, 1-2S, and 2S) were treated in stage II. Then, total 9 treatments in stage III were designated by 3 treatments (tap water, 1S, and 2S) for each 3 strengths in stage II. Each nutrient solution was applied 8 times per day. At vegetative growth stage (54 days after planting), stem length was highest when irrigated 8 times a day with 1S nutrient solution. Both photosynthesis and transpiration rate were higher in 1S than those in other treatments (1-2S, 2S), whereas leaf chlorophyll content was highest in 2S treatment. Ion content of plant treated with 2S was higher than other treatments. Growth (plant height, leaf area, stem length), fresh weight, and dry weight of each plant organ after flower bud formation were better in tap water treatment (1-1-0) than other 1S treatments (1-1-1, 1-1-2). Regarding the number of days to flowering, tap water treatment was the most effective. Thus, after flower bud formation supplying tap water or lower concentration of nutrient solution than those used during the vegetative growth stage was economical in saving chemical fertilizers, shortening the number of days to flowering, reducing salt accumulation in media, saving efforts of leaching, and reducing ground water contamination.

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.160-167
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• 1989

This study was carried out to examine the mycorrhizal development, growth, and nutrient uptake of Quercus serrate seedlings while they were grown for 120 days in a pot medium with and without Pisolithus tinctorius, and also with applications of nitrogen levels. The results were summarized as follows : 1) Inoculated seedlings showed ectomycorrhizal formation of 61. 75%. 2) In the root development, the best nitrogen level was $300{\mu}g/ml$ for inoculated seedlings, and the number of short roots, the number of primary lateral roots and total length of lateral roots were 34.3, 30.7, and 17.2% greater, respectively, than noninoculated seedlings. 3) Growth of shoot, leaf area, total dry weight, and volume of inoculated seedlings were increased 26.9, 52.3, 31.7, and 85.7% greater respectively, than noninoculated seedlings. 4) Inoculated seedlings were more enhanced in the uptake of N, P, K, and Ca than noninoculated seedlings, and the enhanced uptake was best shown at $300{\mu}g$ N/ml treatment.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.692-698
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• 2001

This study has been carried out to estimate aboveground biomass and net primary production(NPP) in an average 41-years-old Quercus variabilis stand of Gongju area, 45-years-old Quercus variabilis stand of Pohang area, and 54-years-old Quercus variabilis stand of Yangyang area. Ten sample trees were cut in each forest and soil samples were collected in July to August, 2000. Estimation for aboveground biomass and net primary production were made by the equation model $Wt=aD^b$ where Wt is oven dry weight in kg and D is DBH in cm. Total aboveground biomass was 91.31ton/ha in Gongju area, 207.6ton/ha in Pohang area, and 71.39ton/ha in Yangyang area. The aboveground biomass 207.6ton/ha in Pohang area is the highest biomass production among the amount of biomass in Quercus variabils stands reported in Korea. The proportion of each tree component to total aboveground biomass was high in order of bolewood, bolebark, branches and leaves in the three forests. Aboveground total net primary production was estimated at 7.8ton/ha in Gongju area, 11.5ton/ha in Pohang area, and 6.40ton/ha in Yangyang area. There were at least 2 times higher total aboveground biomass in Pohang area than in the Gongju and Yangyang areas because of climate difference among the study areas.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.205-210
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• 2008

Sedum kamtschaticum has been used as one of the native valuable plants for ornamental purpose. This experiment was conducted to find out the optimum media for pot cultured Sedum kamtschaticum using peatmoss and coir-based mixtures. Four mixtures such as peatmoss:perlite(5:5, v/v), peatmoss:perlite(7:3, v/v), coir:perlite(5:5, v/v), and coir:perlite(7:3, v/v) were used. Plants were irrigated with a Sonneveld solution in an ebb & flow system. The content of T-N, K, and Ca in the peatmoss-based media was higher than those of the coir-based media. The concentration of T-N, K, and Ca in the shoots of Sedum kamtschaticum increased when plants were cultured with peatmoss-based media. In the peatmoss-based media, plant growth, such as number of branches, leaf length and shoot fresh and dry weights, were significantly increased than those of plant grown in the coir-based media. As the results, the optimum media for pot cultured Sedum kamtschaticum in an ebb & flow system was considered to be the peatmoss-based mixtures.