• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.6
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• pp.82-91
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• 2002

This study was conducted to investigate methods to overcome serious problems in hedge making. The growth response of Enonymus japonica was investigated, using different sizes of nonwoven fabric containers. Changes of shoot length, fresh weight and chlorophyll contents were measured a period of growth in each size of container. The results of this study are as follows; 1) The maximum growth of shoot length in all treatments was observed in May and August. The significant difference was found in the smaller size of container containing a less amount of soil than the control. 2) The soil amount of rhizosphere for the production of a standardized hedge seemed to be over 2,400-3,600㎤ per plant. 3) The depth of containers had a greater influence on growth of shoot length than the width of containers. 4) The fresh weight in 40cm width containers and 30$\times$20cm containers was similar to the control, but the rest of the containers showed significant difference compared with the control. 5) A significant difference of chlorophyll content was found in A, B, C, D and G treatment but I treatment did not show significant difference at the 5% level.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.83-92
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• 1973

In order to compare the forage value and to promote the growth without the hindrance of rice transplanting period for several forage crops as prior crops of paddy field, this experiment was conducted. Three kinds of foliar application, such solution as Urea, Gibb. and Gibb. +Urea were applied to promote the growth. The results gained are summarized as follows; 1. According to the forage crops, there were large difference of yields. The rankings of yield were shown as follows; Fresh weightㆍDry weight : Oats. Italian rye grass. White clover. Corn. Soybean. Crude protein content: Soybean. White clover. Corn. Italian rye grass. Oats. Crude protein Yield: White clover. Italian rye grass. Oats. Corn. Soybean. 2. The ranking of suitable forage crops as prior crops of paddy field were Oats, Italian rye grass, White clover, but Corn and Soybean were unsuited. 3. In general, length of stem, length and width of leaf were enlarged such rank as foliar application of Urea, Gibb. and Gibb. + Urea solution. There were apt to be increased fresh and dry weight by growth of stem length, these trend were shown among all crops and between foliar applications of same crops. 4. All crops were shown not only promoted growth but also increased yield by every treatments. The order of application effects were as follows; Fresh weigthㆍDry weigth: Gibb., Gibb. +Urea, Urea. Crude protein content and yield: Urea, Gibb, Gibb. + Urea. 5. In Oats, heading date was more accelerated 1, 2 and 3 days than control by foliar application of Urea, Gibb. and Gibb. + Urea respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.83-87
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• 1972

The fresh-water shrimp, Macrobrachium nipponensis (DE HAAN) is one of the largest of the shrimp species and one of the most important types fo protein food in fresh water fisheries. It can be found from Cheju island in the touth to Chung-ju in river or swamp, in the north. The breeding of these shrimps was studied by Chun and Yu (1967) and the relative growth was reported by author (1970a), but they did'nt provide other ecological features widely found in their natural environment. Shrimps were collected from the Nak Dong River, near Pusan, Korea once a month, from March to December 1963. The following is a summary of the results. 1. Larvae hatch from May to September, mainly in the month of July. 2. The average sex ratio ($male/female{\times}100$) is $62.9\%$ and goes down during the spawning season and rises from fall to spring season. 3. The minimum size of the female with eggs is aproximately 4.2cm in body length 3.5 gr in body weight, and 1.5 cm in carapace length. 4. Most shrimps of 5.75-7.75 cm in body length lay eggs. 5. The dorsal spines of the rostrum are 10-16(mode13) in number and the ventral spines of the rostrum are 1-5 (mode 3) in number.

• Korean Journal of Organic Agriculture
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• v.10 no.1
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• pp.65-74
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• 2002

The results of the experiment about the effect of the length of electrical stimulation treatment time on the yield components and NO$_3$ content in edible parts of 2 cherry type radishes(Raphanus salivas L.) were like followings. 1. The 2 hours electrical stimulation promoted the length of leaf and the enlargement of the root diameter of 'Comet' and 'Sakuranbo' cultivars, and their root diameters were increased by 14.7% and 12.8% respectively than that of the control. 2, The plot which showed the highest root fresh weight was the 2 hours stimulation plot in 'Comet' and 8 hours stimulation plot in 'Sakuranbo', and these results were approximately 39% higher than that of the control. 3. All of the electrically stimulated plots of 'Comet' and 'Sakuranbo' showed higher NO$^{[-10]}$ $_3$content in roots than the control. And the amount of NO$^{[-10]}$ 3 in their roots showed a remarkable positive correlation with the root diameter, the root fresh weight and the total fresh weight.

• Journal of Environmental Science International
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• v.25 no.1
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• pp.147-153
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• 2016

To investigate the impact of the number of runners developed from daughter plants during seedling on sapling growth and development during phase of first cluster, we examined four treatment groups that had 3-4, 5-6, 7-8, and 9-10 runners. As of June $5^{th}$, the group with 9-10 runners showed the highest number of saplings with more than 2 leaves, followed by groups with 7-8, 5-6, and 3-4 runners. Although observation on June $25^{th}$ and July $15^{th}$ showed a similar tendency for sapling numbers, no significant difference was detected between groups with 7-8 and 9-10 runners. The length of runners in the treated groups was similar to that in groups with 3-4 and 5-6 runners, with lengths of 49.4 mm and 48.0 mm, respectively, but runner length was significantly shorter in the group with 7-8 runners. Both the thickness and the weight of runners were highest in the group with 3-4 runners. The growth and development of daughter plants and root weight were similar between the groups with 3-4 and 5-6 runners, whereas both values were lower in groups with 7-8 and 9-10 runners. While stem crown thickness values were 8-7 mm and 8.5 mm in groups with 3-4 and 5-6 runners, respectively, groups with 7-8 and 9-10 runners had thinner stems of 7.1 mm and 6.2 mm, respectively. The fresh weight of saplings decreased as the number of runners increased. From the phase first cluster, leaf area and fresh weight were remarkably low in groups with 7-8 and 9-10 runners. Taken together, these results can be used to increase the production of high-quality saplings by providing a foundation for studies to investigate the impact of the number of runners developed from daughter plants on growth and development during the seedling period and the phase first cluster.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.178-182
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• 2007

Rauvolfia serpentina (L.) Benth. ex Kurz is a medicinal plant and an endangered tropical rainforest plant species. Since the field cultivation that aims to fulfill the industrial needs is never accomplished, tissue culture appears to be the most feasible way to improve the quality and quantity of R. serpentina. This experiment used two kinds of explants (roots and shoots) to induce optimal root formation in different combinations of auxin and photoperiod. Each explants exhibited different responses on given treatments. Differentiated root could be produced from explants cultured in IBA 20 mg/L with and without light. The highest number of roots, root length and root weight induced from shoot explants were effective on MS medium containing IBA 20 mg/L and incubated under dark condition, while highest total weight (callus and root) from root explants cultured on MS medium supplemented 10 mg/L IBA and 10 mg/L NAA and incubated under day length (11/13 hr). The root induced from shoot explants produced the highest major alkaloid content. The highest content of ajmaline (2.17 ppm fresh weight) and reserpine (1.30 ppm fresh weight) were observed in shoot explants cultured in MS medium containing combination of IBA 10 mg/L and NAA 10 mg/L and incubated under dark condition, yohimbine (1.47 ppm fresh weight) was in the shoot explants cultured in MS medium containing NAA 20 mg/L and incubated under day length, while serpentine was absent.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.2
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• pp.160-167
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• 1992

The growth of weeds and some other plants has been considered to be inhibited by sicklepod(Cassia tora L.) sharing the habitat. The study was conducted, for the first time, to propose that this phenomenon is not only due to competition for physical and nutritional conditions but also due to allelopathy. In addition, autotoxicity of sicklepod was examined. The results are summarized as follows. 1. Rice sheath length reduced progressively from 18 % to 36 % with increasing the concentration of treating aqueous extracts of sickle pod seeds, but rice germination was not affected. In contrast, radish hypocotyl length was not reduced by the aqueous extract treatment but radish germination was significantly reduced by 66 % at 1 : 10 and 1 : 5 treatment. 2. Total chlorophyll contents in rice seedling decreased from 50 % to 65 % by treatment of seed aqueous extracts diluted from 1 : 50 to 1 : 5 ratio. 3. Aqueous extracts of sicklepod leaves significantly reduced hypocotyl length and fresh weight in radish and germination in rice, but mung bean was slightly affected by aqueous extracts only in fresh weight. 4. Volatiles from fresh, immature seeds with husk reduced the radish germination and seedling growth and radish root growth appeared to be more sensitive to the exposure to volatiles from fresh immature seeds than both germination and hypocotyl growth. 5. Volatiles from sickepod leaves inhibited germination and growth of radish, rice and mung bean, and seedling growth was more sensitive to volatiles from leaves than germination. 6. Volatiles from sicklepod leaves reduced germination and radicle length of sicklepod itself. 7. Collectively, it is concluded that there are water-soluble and volatile substances responsible for allelopathy in sicklepod.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.336-342
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• 1988

An experiment was carried out to know the effects of paclobutrazol application time on the lodging related traits and yield of a rice variety. Seomjinbyeo, at two nitrogen leveles. Paclobutrazol (3kg 10a of 0.6% G) was applied 43, 33, 23, and 13 days before heading (DBH) and lodging related traits were observed 10, 20, 30, and 40 days after heading (DAH). Earlier applications of paclobutrazol reduced the length of lower internodes and later applications reduced the upper internodes. Culm length tended to decrease as time of paclobutrazol application delayed. Although lodging was not occurred in all plots. lodging index of paclobutrazol treated plots was lower than that of control and increased with maturity, Fresh weight of shoot increased up to 30 DAH and then decreased. Both fresh weight and breaking strength did not show consistent tendency with time of paclobutrazol application and observation. Direct effect of shoot fresh weight contributing to lodging index decreased with maturity. but that of breaking strength and culm length was similar during the ripening stages. Direct effect contributing to lodging index was greater in the order of breaking strength culm length. and fresh weight 40 DAH. Starch content of culm base decreased up to 20 DAH and then increased up to 40 DAH. Cellulose content increased up to 20 DAH, but hemicellulose and lignin did not change significantly during the ripening stages. Starch, cellulose, hemicellulose, and lignin contents of culm base did not correlated with breaking strength and time of paclobutrazol application did not show consistent results. Paclobutrazol applied 13 DBH did not reduce yield of rice. but the earlier applications reduced yield due to a reduced number of spikelets per panicle.

• Plant Resources
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• v.4 no.1
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• pp.6-12
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• 2001

Growth and yield of licorice were investigated under the different conditions of ridge height, planting density, and irrigation in order to establish its cultural practices for the domestic production with the aim to substitute the import. Seedlings were grown under low ridge(20cm) and high ridge(40cm) in low density plot(60$\times$30cm) and high density plot(40$\times$30cm), respectively. The low ridge cultivation of large seedlings increased plant height and root length under low density, and stem and root diameter under high density compared to the high ridge cultivation. In the high ridge cultivation, high density plot was 1.1 to 1.3 times in plant height, root length, stem and root diameter as high as low density one. Fresh and dry weight of plant and root in high ridge were 1.3 to 1.5 times as high as those in low one. The growth of small seedlings(4~10g) were generally poor compared to that of large seedlings. High density plot in low ridge showed the good growth characteristics including plant height, root length, stem and root diameter, and number of branch. High density plot was 1.4 to 1.6 times in fresh and dry weight of plant and root as high as low density plot. In the seasonal changes of growth under various irrigation regimes, the twice irrigation a day produced the more number of leaf than the other regimes since around 46 days after transplanting. The former irrigation resulted in 1.2 to 1.4 times in plant height as long as the other irrigations around 26 days after transplanting and then the difference was increased to 1.6 to 2.0 times around 64 days after transplanting. Under the twice irrigation a day, plant height, root length, stem diameter, root diameter, number of leaf, fresh plant weight, dry plant weight, fresh root weight, dry root weight were 1.6 to 2.0, 1.1, 1.2 to 1.6, 1.3 to 1.8, 1.9 to 2.7, 1.7 to 8.0, 1.6 to 2.8,2.0 to 3.0, 1.6 to 2.7 times as high as those under the other irrigation regimes, respectively.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.287-290
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• 1995

This study was conducted to elucidate the effect of physical properties of soil in nursery bed with different densities on growth of ginseng seedling. Stem length, leaf length and leaf width of ginseng seedling showed the decreasing tendency with increasing the hardness of the nursery soil. Fresh root weight per seedling and number of available seedlings were increased significantly with decrease of the soil hardness. For solid, liquid phases, bulk density and hardness of soil, negative correlations were shown in stem length, leaf length, leaf width, root weight per seeding, and number t of available seedlings. On the other hand, gas phase, air permeability and porosity of soil had positive correlations with stem length, leaf length, leaf width, root weight per seedling and number of available seedlings. Key words Yang-Jik nursery, ginseng seedling, soil physical properties.