• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.194-198
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• 2007

Yield and ginsenoside contents of ginseng (Panax ginseng C. A. Meyer) is affected by light intensity and quality, and the color and the thickness of PE shading net when PE net is utilized for shading material. This study was carried out to investigate the effect of light quality on root yield and ginsenoside contents off-year-old ginseng by using polyethylene shading net with each blue and yellow color, Spectral irradiance under blue and yellow shading net showed the peak at 498 nm and 606 nm, respectively, which made distinct difference in light quality. Heat injury ratio of blue shading net was increased distinctly more than that of yellow shading net in summer season because of higher transmitted quantum (23%)and air temperature (0.3 $^{\circ}$C) in blue shading net than those of yellow shading net. Chlorophyll content and leaf area under yellow shading net were higher than those of blue shading net, and its heat injury ratio was lower than those of blue. These effects may led to 48% higher increase of root yield under yellow shading net than that under blue shading net. The content of total ginsenoside in taproot was not significantly differed between blue and yellow shading net, while the content in lateral and fine root was significantly increased in blue shading net compared to yellow shading net. PDM ratio of blue shading net showed more significant increase in lateral root than that of yellow shading net. All of Rb$_1$/Rg$_1$ ratio in three parts of root under blue shading net was higher than that of yellow shading net, but there were no significant increase in the ratio of lateral root.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.475-483
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• 2012

Recently, agricultural lands decrease sharply, which was caused by urbanization, land consolidation, road construction, and innovation city construction, etc. In particular, Goyang, Chenan and Wonju city were had severe land use change. Therefore, we analyzed changes of land use, soil properties, and soil information in order to provide the basic soil information and soil management practice in these cities. The results are summarized as follows. The area of crop cultivated land in Korea (2011) was reduced to 17.3ha compared to ones from the previous year (2009). The paddy field decreased by 24.2 ha but, upland field increased by 7.0 ha. The reasons for the reduction of the paddy field were converting paddy field to upland (20.7 ha) > public facilities (3.2) ${\geq}$ building (3.2) > idle land (1.3) > and others (0.9). Other reasons for reduction in the upland field were switching upland to paddy field, (20.7 ha) > land developed (4.5) > and restoration (0.3) respectively. The main reason of converting paddy field to upland was changing from rice to more profitable upland or greenhouse crops. The cropland area (paddy fields, upland, orchard) of Goyang, Cheonan, and Wonju city were reduced to 1,466 ha, 9,708 ha and 6,980 ha respectively. The ratio of cropland area in each city was reduced by 45~25% dramatically compared to upland soil survey project in Korea (1995~1999). These data were compared with MiFAFF statistics data to use for land use cover map of Ministry of environment. But they were differences significantly. Therefore, intensive investigation should be advised throughout the utilization plan. The paddy fields located in small valley in Wonju city were changed into upland or orchard. The drainage classes of soil have been deteriorated because the flows of water were intercepted by road construction and other disturbance to water flows. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also to fallow and soil dressing on paddy in Wonju city. The soil suitability classes of paddy field in Wonju innovation city were the 3rd grade for 70.8% of the area and the 4th grade for 29.2%. The soil suitability classes of upland was the 4th grade for 88.7% of the area. Fortunately, good soil suitability classes were not belong to innovation city in Wonju. So, the good farm land should be conserved and revise the related law.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.252-261
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• 2003

Although the young spike of barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) is known as the most susceptible part to spring cold injury, the risk of cold injury is apt to be ignored in most breeding program due to the importance of early maturity. Based on these aspects, the types and inducing time, temperature conditions for induction and effects of cold injury on growth and yield in this study were investigated under greenhouse and field conditions through three years (1997-1999). In natural condition, low temperature around -2.4∼$-10.2^{\circ}C$ caused the death of plant. Several cold injury types such as partial degeneration of spike, partial discoloration of leaf, spike and awn, discoloration of culm and white spike were observed at low temperature around $-3.1^{\circ}C$. Low temperature around -2.4∼$-8.6^{\circ}C$ and 1.3-$7.6^{\circ}C$ caused degeneration and sterility of spike, respectively. Most materials were prepared to the spikelet foundation stage, spikelet differentiation stage, development stage of flower organ, booting stage and heading stage, which were known having risk for cold injury in field condition. Although most of the controlled stages were sensitive to the induced low temperature, booting stage was the most sensitive stage for cold injury. All of growth stages which were treated-heading stage, booting stage, development stage of flower organ, spikelet differentiation stage, spikelet foundation stage-were responded to low temperature treatment but the symptoms revealed were very specific according to the growth stages. Ears of plant in heading stage were discolored to white. Ears of plant in booting stage were degenerated in all or part of one. Plants in spikelet differentiation stage were sterile in all or part of one. When tried to detect the specific differences between normal and cold injured plants in appearance, spike length, distance between spike and flag leaf and the first internode length could be the critical points for occurrence of spike death caused by cold injury. In barley, the elongation of spike was stopped on 3.2cm after occurrence of spike degeneration, 4.7cm after occurrence of partial degeneration of spike, 5.0cm after occurrence of white spike. In wheat, it was stopped on 1.6cm after occurrence of stem death, 3.3cm after occurrence of spike degeneration, 8.3cm after occurrence of partial degeneration of spike, 8.1cm after occurrence of white spike, 7.5cm after partial discoloration of leaf and 9.3cm after partial discoloration of spike. The obtained results from low temperature treatment induced in growth chamber were similar to the field experiment, Beacuse the death of spikes was more when low temperature was treated two times than one times, the temperature should be upgrade to -3$^{\circ}C$ in order to get the same condition with field test.

• Journal of Korean Home Economics Education Association
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• v.16 no.3
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• pp.131-146
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• 2004

The Purpose of this study is to suggest strategies for environmental education through the Practical Arts(TechnologyㆍHome economics) Subject in a viewpoint of the clothing & textiles resources to resolve problems in the clothing life area. For this, this study was carried out through review of literature which is related with the consumption, the environmental problems, the environmental policies, and regulations of the government and new environmental technologies, of clothing & textiles industries and environmental education. The major findings of the study were as follows; 1) The environmental education system model in a viewpoint of the Clothing & Textiles resources was developed. This model system is consisted with interactions on school, government, industry, home and non-government organizations. Thus, the fact that Practical Arts(TechnologyㆍHome economics) Subject were the most effective subject to teaching the environmental education viewpoint of the Clothing & Textiles resources was confirmed. 2) The standards were analysed out to analyse the contents in the clothing area of the Practical Arts(TechnologyㆍHome economics) Subject. It were consist of 4 factors and 12 elements under the factors: Awareness of clothing & textile resources(clothing consumption, production of clothing & textile and environmental problems). Planning and buying of clothing(planning, buying), Management of clothing(understand of textile. human body & environment, laundering and Environmental pollution, arrangement & conservation) Recycling & exhaust of clothing(contribution, redesign, recycling, exhaust) 3) Analysing the current Practical Arts (TechnologyㆍHome economics) subject from the Environmental education in the clothing section, the environmental education related with clothing were taught the most in the middle school course, and environmental contents were concentrated in the recycling factors. but not so much on other factors. 4) After analysing the Practical Arts (TechnologyㆍHome economics) subject, the strategies were suggested for reinforcing the environmental education in the clothing of the Practical Arts(TechnologyㆍHome economics) subject.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.83-89
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• 1990

A sweet corn hybrid, Golden Cross Bantam 70, was grown at 0, 5, 10, 15 and 20kg/10a of nitrogen (N) under the transparent P. E. film mulch to find the best yield evaluation method. Culm length, ear height, number of tillers increased and silking date was earlier by 1-2 days with increased N level. Leaf area index of main culm at harvest increased with increased N level. Marketable ears were divided into two classes according to the whole sale market price; the frist grade of which husked ear weight over 150g (unhusked ear weight 230g) and the second grade of which husked ear weight between 100 and 150g (unhusked ear weight between 180 and 230g). Average length, thickness, and weight of both grades of marketable ears were not different among the N levels. The proportion of the first grade increased with increased N level. However, total number and weight of marketable ears and gross income per 10a calculated considering weight and number of ears increased with increased N level. There were highly positive correlations between gross income and ear number or ear weight per l0a. The number and weight of marketable ears were underestimated at high N levels compared with gross income. Dry matter yield of stover ranged 740-963kg/10a and increased with increased N level with 20. 8-24.5% dry matter content. Rice black-streaked dwarf virus infection rate was 11.8-15.0%, but it was not related to N level. N concentration in ear was similar but that in stover increased with increased N level. Total N uptake increased but N recovery decreased with increased N level.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.428-439
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• 2020

This study was carried out to investigate the effect of PO film on the increase of crop yield and energy saving through PO and PE film greenhouse application and comparison test. As a experimental greenhouse, two single span greenhouses (1-1 W) and two double span greenhouses (1-2 W) were used. During winter season, PO film (0.15 mm outer layer, 0.10mm inner layer) was used as a covering material of greenhouse in double layers for double-span (B15) and single-span(B21), and PE film used for double-span (B15), and single-span (B23) as a control. The experimental vegetable was tomato(Solanum lycopersicum L.) cultivated in soil and the cultivar of that was 'Happiness'. That was cultivated from December 3, 2019 to April 30, 2020. The temperature at night inside the greenhouse was maintained at 15℃, and the side and roof windows were opened to maintain 23 ~ 24℃ during the day. As a result, this study showed that the yield in single-span greenhouse(B21) covered with a PO film increased 20% and that in double-span greenhouse (B16) increased by 9% compared to the greenhouse covered with a PE film (B23, B15). Fuel consumption of the single-span greenhouse (B21) with the cover of PO film was reduced by 12.4% and that of double-span greenhouse was done by 11.5% compared to that of the PE film greenhouse (B23, B15) without any difference between them in growing state.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.312-318
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• 2010

This study was carried out to develop and test a prototype program that recommends the nitrogen topdressing rate using the color digital camera image taken from rice field at panicle initiation stage (PIS). This program comprises four models to estimate shoot N content (PNup) by color digital image analysis, shoot N accumulation from PIS to maturity (PHNup), yield, and protein content of rice. The models were formulated using data set from N rate experiments in 2008. PNup was found to be estimated by non-linear regression model using canopy cover and normalized green values calculated from color digital image analysis as predictor variables. PHNup could be predicted by quadratic regression model from PNup and N fertilization rate at panicle initiation stage with $R^2$ of 0.923. Yield and protein content of rice could also be predicted by quadratic regression models using PNup and PHNup as predictor variables with $R^2$ of 0.859 and 0.804, respectively. The performance of the program integrating the above models to recommend N topdressing rate at PIS was field-tested in 2009. N topdressing rate prescribed for the target protein content of 6.0% by the program were lower by about 30% compared to the fixed rate of 30% that is recommended conventionally as the split application rate of N fertilizer at PIS, while rice yield in the plots top-dressed with the prescribed N rate were not different from those of the plots top-dressed with the fixed N rates of 30% and showed a little lower or similar protein content of rice as well. And coefficients of variation in rice yield and quality parameters were reduced substantially by the prescribed N topdressing. These results indicate that the N rate recommendation using the analysis of color digital camera image is promising to be applied for precise management of N fertilization. However, for the universal and practical application the component models of the program are needed to be improved so as to be applicable to the diverse edaphic and climatic condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.491-497
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• 2015

Small-sized tuber of sweet potato (Ipomoea batatas Lam.) is more preferred by Korean consumers, because it is convenient to eat with hands, and can easily be steamed or roasted in small pan as a healthy snack for a small family. The present study was aimed to investigate the effect of high-density plantings and harvesting times on production of smallsized tuber (50~200 g). Four varieties ('Annobeny', 'Daeyumi', 'Shinzami', and 'Yeonhwangmi') were planted in 2-row zigzag high-density planting ($75{\times}30cm$, A; $75{\times}25cm$, B) and 1-row planting ($75{\times}25cm$, control) covered with black vinyl film on May 23th, 2014. Marketable yields and small-sized tuber yields were compared between 120- and 150-day harvesting. Vine length and fresh weight per plant were significantly decreased in 2-row planting A and B plots compared to the control at 120 days after planting. Weight of tuber per plant, mean weight of tuber and number of tuber per plant were significantly decreased in 120-day harvesting of A and B plots than in the control. Marketable yields per 10a were increased by 17% ($2.4ton{\cdot}10a^{-1}$) and 8% ($2.6ton{\cdot}10a^{-1}$) in 120-day harvesting of A and B plots compared to the control ($2.4ton{\cdot}10a^{-1}$), and those were largely increased by 29% ($4.0ton{\cdot}10a^{-1}$) and 26% ($3.9ton{\cdot}10a^{-1}$) in 150-day harvesting than in the control ($3.1ton{\cdot}10a^{-1}$). Proportions of small size tuber (50~200 g) were increased by about 65% in 150-day harvesting of A and B plots compared to the control (55.3%). Small-size tuber yield and marketable yield were highly increased in 150-day harvesting of 2-row zigzag high-density planting A ($75{\times}30cm$).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.6-14
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• 1980

One of the physiological disease, sudden wiliting of Yushin variety suggested that low sunlight, excessive nitrogen application, and highly reduced soil condions either singly or combined, might be possible causes of the disorder. Some visual symptom of sudden wilting are discoloration of leaves, development of nodal roots above the soil surface, total root rot, and lodging. Those observations led to the hypothesis that suffocation of root tissues was a direct cause of the wilting. The oxygen transport characteristics of Yushin, IR262 and Tongil were examined by two methods. First, Soil-cultured plants of the three varieties were subjected to paraffin treatment to decrease the oxygen supply from the air to root tissues through the soil-water system, liquid paraffin was applied to the water surface in the pots at panicle formation stage. In this experiment, sudden wilting was observed of Yushin and IR262 at about a week after the treatment, but Tongil remained green and healthy. Wilting-resistant variety Tongil had higher oxygen release, whereas the susceptible Yushin and IR262 had lower oxygen release. Second, the number and size of the air spaces in each internode were investigated in the 5th internode from the top, all three varieties have a similar number of air spaces, although the air spaces of Thongil were larger. In the 4th internode, Tongil had plenty air spaces, Yushin and one of the Yushin's parents IR262 had scanty or none. The observations indicated that the ability of Yushin and IR262 for oxygen transport is very limited compared with that of Tongil. The limited oxygen supply due to poor development of air space in internode of rice plants may cause suffocation of root tissues, weaken metabolic activity of the tissues, and induce root rot, subsequently inducing sudden wilting and lodging under unfavorable weather, soil and cultural conditions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.162-173
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• 2009

Information on the expected geographical shift of suitable zones for growing crops under future climate is a starting point of adaptation planning in agriculture and is attracting much concern from policy makers as well as researchers. Few practical schemes have been developed, however, because of the difficulty in implementing the site-selection concept at an analytical level. In this study, we suggest site-selection criteria for quality Fuji apple production and integrate geospatial data and information available in public domains (e.g., digital elevation model, digital soil maps, digital climate maps, and predictive models for agroclimate and fruit quality) to implement this concept on a GIS platform. Primary criterion for selecting sites suitable for Fuji apple production includes land cover, topography, and soil texture. When the primary criterion is satisfied, climatic conditions such as the length of frost free season, freezing risk during the overwintering period, and the late frost risk in spring are tested as the secondary criterion. Finally, the third criterion checks for fruit quality such as color and shape. Land attributes related to these factors in each criterion were implemented in ArcGIS environment as relevant raster layers for spatial analysis, and retrieval procedures were automated by writing programs compatible with ArcGIS. This scheme was applied to the A1B projected climates for South Korea in the future normal years (2011-2040, 2041-2070, and 2071-2100) as well as the current climate condition observed in 1971-2000 for selecting the sites suitable for quality Fuji apple production in each period. Results showed that this scheme can figure out the geographical shift of suitable zones at landscape scales as well as the latitudinal shift of northern limit for cultivation at national or regional scales.