• Korean Journal of Organic Agriculture
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• v.6 no.1
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• pp.127-132
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• 1997

This experiment was carried out to examine the effect of various functional materials such as bioceramic podwers, crushed shells and elvanites supplemented to the each substrate on the seedlings growth of rices. The rice seedlings were grown in pots filled with substrates supplemented with bioceramic podwers, crushed shells and elvanites. The growth of rice seedlings in terms of plant height, stem diameter, root length and leaf width, plant fresh and dry weight was promoted by adding the bioceramic powders (2 to 3g/kg), crushed shells (10g/kg) or elvanites (20 to 40g/kg). Plant height was also promoted by the adding of bioceramic powder from 16 days after treatment, whereas crushed shells and elvanites from 10 days after treatment. Especially, root growth was greatly influenced by bioceramic powder, whereas the shoot growth(leaves and stem) was stimulated by the crushed shells and elvanites supplemented into each substrate. In the field, plant growth in terms of plant height, leaf length and leaf width were also influenced by crushed shells and elvanites at 74 days after treatment. The growth of rices in terms of tiller number, spikelets, panicles and spikelets/panicle was incresed by adding the crushed shells and elvanites from 100 to 200g per m2.

• Journal of Life Science
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• v.13 no.6
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• pp.889-895
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• 2003

This experiment was carried out to investigate the effect of subirrigation of Dolrido on the growth and development of stem cutting and young roes plant. Plant growth was measured at 20, 40, and 60 days after subirrigation of Dolrido. Plant height, stem diameter, number of leaves, leaf area and root length of cutting rose subirrigation were more affected than those of control. The growth of young seedling was significantly affected by subirrigation of Dolrido. Plant height, number of leaves, stem diameter, leaf area, fresh and dry weight were increased with subirrigation of Dolrido. However, T/R ratio was not affected by subirrigation of Dolrido. Growth of seedlings was promoted after 60 days treatment of Dolrido.

• Journal of the Korean Wood Science and Technology
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• v.49 no.4
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• pp.384-393
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• 2021

Recently, due to environmental and toxicity issues, there has been increasing attention on research regarding natural products that can reduce the use of chemical fertilizers. Wood extracts derived from the biorefining process contain various fertilizer ingredients. HPLC analysis revealed that wood extract contains approximately 5.2% hemicellulosic sugar. The growth of lettuce (Lactuca sativa) upon treatment with wood extract (extract obtained from steam-exploded pine) or water-soluble fertilizers containing different nutrients was analyzed in this study. After two weeks, the growth characteristics of lettuce as affected by wood extract or water-soluble fertilizers were significantly different. The effect of water-soluble fertilizers containing ascorbic acid, magnesium sulfate, citric acid, potassium nitrate, amino acids, or seaweed extract was less desirable than that of wood extracts regarding plant height (18.6 cm), number of leaves (10), leaf length (14.1 cm), shoot fresh wight (9.8 g/plant), root fresh weight (0.8 g/plant) and shoot dry weight (0.6 g/plant). The plant height, number of leaves, leaf length, shoot fresh wight, root fresh weight, shoot dry weight of water-soluble fertilizers containing wood extract were significantly different compared to the control (plant height :13.5 cm, number of leaves : 7, leaf length : 9.4 cm, shoot fresh wight : 5.3 g/plant, root fresh weight : 0.7 g/plant, shoot dry weight : 0.4 g/plant, root dry weight : 0.07 g/plant). From these results, it was concluded that wood extract can be used as a potential water-soluble fertilizer to increase the yield of leafy vegetables.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.3
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• pp.169-174
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• 1991

For simple estimation of pasture production and nutritive value in relation to height of orchardgrass (Ductylis glomumtu L.), the experiment was carried out in a pasture mixture dominated by orchardgrass. The samples of grasses were harvested at the heights of about 30, 40, 50, 70 and 90 cm at the first harvest under different percentage of 100 (grass coverage): 0 (bareland), 80 : 20, 60 : 40, 40 : 60 and 20 : 80, respectively. As the height of orchardgrass was increased, fresh and dry matter (DM) yield were significantly increased. The regression equation between DM yield (Y) and height (X) was Y=ll. 5390 X- 146.60 (r=O. 9414 * * ). Also the higher bareland, the lower pasture production was observed. As the plant height at the first harvest was increased, the contents of crude (C) protein, C. fat, C. ash and relative feed value were markedly decreased. On the other hand, the contents of C. fiber, NFE, NDF. ADF, cellulose and lignin were significantly increased, respectively. The higher height, the lower DM digestibility was found. The equation between digestibility (Y) and height (X) was Y=- 0.2193 X+ 80.99 (r = - 0.9862**). Considering DM yield, digestibility and crude protein, the optimum height of orchardgrass at the first harvest was 59 to 67crn for better pasture production and nutritive value.

• Journal of computational fluids engineering
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• v.21 no.4
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• pp.78-84
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• 2016

In this paper, turbulence models for considering roughness in the open source code(OpenFOAM) was investigated. Wall function in the RANS(Reynolds-averaged Navier - Stokes) turbulence model was modified considering roughness on the flat plate by using roughness function. Correlation between the first layer height in the CFD model and roughness height of the plate was observed, and the most proper roughness function, and the first layer height from the plate wall in the CFD analysis was suggested in this paper.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.30-36
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• 2011

Effect of daminozide concentration and application methods, in combination with different planting period, on the growth of chrysanthemum was investigated for small pot-plant production. Daminozide, a plant growth regulator widely used for plant height control, was applied by drench or sub-application. For pot chrysanthemums of first planting time, plant height was reduced over $4,000mg{\cdot}L^{-1}$, when daminozide was drenched directly into the pot medium. However, $5,000mg{\cdot}L^{-1}$ of daminozide drench affected plant height reduction for secondarily planted pot chrysanthemum. Analysis of variance revealed the plant height was affected by planting time. For sub-application experiment of daminozide, it showed that the daminozide affected the number of flower buds formation and fresh and dry weight. These results suggest that planting period affected growth retardation of chrysanthemum. Therefore, application of growth retardant in combination with planting time and application methods may provide more efficient growth control for pot-chrysanthemum production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.473-480
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• 1983

To obtain basic information on the Korean local com lines a total of 57 lines were selected from 1,000 Korean local collection at Chungnam National University, and classified by principal component analysis, and genetic nature was investigated. There were a great variation in mean values of plant characters of the lines. The mean values of plant characters except for density of kernels varied with types of crossing. All characters except for tasselling dates were reduced in magnitude when selfed, while those characters were increased when topcrossed. The inbreeding depression varied with plant characters and lines. The characters such as yield, kernel weight per ear, ear weight and plant height showed great degree of inbreeding depression. Group I showed high inbreeding depression in such characters as 100 kernel weight, leaf number, plant height and days to tasselling, while group II showed high inbreeding depression in other plant characters. Heterosis of plant characters varied also with lines. The ear weight, kernel weight per ear, yield, 100 kernel weight, and plant height were some of the plant characters showing high heterosis. Group II showed high values of heterosis in such characters as ear length, ear diameter, ear weight, kernel weight per ear, 100 kernel weight and leaf length, while group I was high in heterosis in other plant characters. The degree of homozygosity was highest in ear weight (79.1%) and lowest in ear number per plant (-2.1%). Group II showed higher degree of homozygosity than group I. Correlation coefficients between characters of sibbed and topcrossed lines were positive for all characters. Highly significant correlation coefficients between sibbed and topcrossed lines were obtained especially for characters such as ear number per plant, plant height, leaf length and yield per plot.

• Journal of Ecology and Environment
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• v.41 no.1
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• pp.1-8
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• 2017

Background: Though the biomass of floral vegetation in understory plant communities in a forested ecosystem only accounts for less than 1% of the total biomass of a forest, they contain most of the floral resources of a forest. The diversity of understory honey plants determines visitation rate of pollinators such as honey bee (Apis mellifera) as they provide rich food resources. Since the flower visitation and foraging activity of pollinators lead to the provision of pollination service, it also means the enhancement of plant-pollinator relationship. Therefore, an appropriate management scheme for understory vegetation is essential in order to conserve pollinator population that is decreasing due to habitat destruction and disease infection. This research examined the diversity of understory honey plant and studied how it is related to environmental variables such as (1) canopy density, (2) horizontal heterogeneity of canopy surface height, (3) slope gradient, and (4) distance from roads. Vegetation survey data of 39 plots of mixed forests in Chuncheon, Korea, were used, and possible management practices for understory vegetation were suggested. Results: This study found that 113 species among 141 species of honey plant of the forests were classified as understory vegetation. Also, the understory honey plant diversity is significantly positively correlated with distance from the nearest road and horizontal heterogeneity of canopy surface height and negatively correlated with canopy density. Conclusions: The diversity of understory honey plant vegetation is correlated to vegetation structure and human impact. In order to enhance the diversity of understory honey plant, management of density and height of canopy is necessary. This study suggests that improved diversity of canopy cover through thinning of overstory vegetation can increase the diversity of understory honey plant species.

• Korean Journal of Plant Resources
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• v.31 no.6
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• pp.714-718
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• 2018

A new Gomchwi cultivar 'Sammany' was developed by a cross between Gomchwi (Ligularia fischeri (Ledeb.) Turcz.) and Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai). Gomchwi is a common Korean name referring wild edible plant species within Ligularia genus. 'Sammany' has purple colored petiole ears and petiole trichome is absent. It has 2nd degree leaf vein density. Plant height, leaf length, leaf width and petiole length were 46.2, 19.1, 19.5 and 32.1 cm, respectively. Plant height was higher than 'Gondalbi'. Bolting occurred in mid. July and it flowered from late August to early September. 'Gondalbi' bolted and flowered 26 days earlier than 'Sammany', and consequently has earlier flowering time more than 26 day. Leaf number of 'Sammany' was 156 per plant but 'Gondalbi' had 130. 'Sammany' had thicker leaves (0.61 mm) compared to 'Gondalbi' (0.46 mm). As a result, yield was higher in 'Sammany (1,077 g/plant)' than 'Gondalbi (798 g/plant)' and leaf hardness was lower in 'Sammany ($20.8kg/cm^2$)' compared to 'Gondalbi ($23.0kg/cm^2$)'. In addition, 'Sammany' was found to be moderately resistant to powdery mildew. With enhanced agronomic and pathology traits, 'Sammany' was newly registered as a new Gomchwi cultivar (variety protection no. 131 on May 2017).

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.30-36
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• 2018

Purpose: The objective of this study is to evaluate the effect of cultivation conditions on the growth and glucosinolate content of Chinese cabbage and kale. Methods: Chinese cabbage and kale were grown in three different cultivation conditions, including a plant factory, greenhouse, and open field. Samples were collected at two harvesting times (10 d and 20 d after transplanting the seedlings). Nine growth parameters (plant height, plant width, number of leaves, petiole diameter, SPAD readout, leaf length, leaf width, stem diameter, and plant weight) were measured immediately after harvesting, and the samples were freeze-dried and stored until the glucosinolate content was analyzed. Mean values of the growth parameters and glucosinolate contents were evaluated using Duncan's multiple range tests. Results: The results indicated that the plant parameters of the Chinese cabbage and kale were greater for plants grown in the plant factory and greenhouse. The plant height, width, and weight showed significant differences in the Duncan's multiple range tests at a 5% level. The plant factory also produced greater contents of most of the glucosinolates. Conclusions: Three different cultivation conditions significantly affected the growth and glucosinolate contents of Chinese cabbage and kale. Further study is necessary to investigate other functional components and different vegetable varieties.