• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.92-99
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• 1988

The dark respiration, photosynthesis($CO_2$ refixation), $CO_2$ balance and chlorophyll content of 1st-year conelets and 2nd-year cones of Korean pine(Pinus koraiensis S.et.Z.) were investigated after pollination up to the end of maturation. The results obtained are as follows : 1. The growth of 1st-year conelet was 3.6cm in length. 2.4cm in diameter and 3.058 in dry weighs during the first year. The growth of 2nd-year mature cone was 13.5cm in length, 9.3cm in diameter and 141.0g in dry weight in the late of 2nd-year. 2. The refixation of carbon dioxide released from a cone by the dark respiration was less than 50 percent at light saturation through the growing period. The refixation of carbon dioxide released by dark respiration for one year was 7.3 percent in 1st-year conelets and 8.7 percent in 2nd-year cones. 3. The dark respiration rate of cones by increasing temperature was rapidly increased with increasing temperature up to $25^{\circ}C$. The dark respiration rate of cones was much higher in non-growing season than that in growing season at the same temperature. 4. The rates of dark respiration and $CO_2$ refixation, based on the dry weight, were much higher in 1st-year conelet than that in 2nd-year cone. 5. The $CO_2$ balance for a cone was negative from pollination to the end of maturation. The net dark respiration loss for a cone was 7.23g $CO_2$/year in 1st-year conelet and 164.8g $CO_2$/year in 2nd-year cone. 6. The respiratory loss efficiency for a cone(=$CH_2O$ weight calculated by net dark respiration/dry weight of cone) for one year was 1.61 in 1st-year conelet and 0.81 in 2nd-year cone for one year. 7. The total chlorophyll content of surface scale of the cone was lower than 2mg/g dw through the growing period, and chl. a/b ratio was 2 to 3.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.510-516
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• 2016

This study was conducted to investigate the physiological responses of newly-germinated seedlings of Fraxinus rhynchophylla Hance, Zelkova serrata (Thunb.) Makino, Betula costata Trautv. and Quercus variabilis Blume to open-field experimental warming. The seedlings in the warmed plots were warmed with $2.7^{\circ}C$ higher air temperature than those in the control plots using infrared heaters since April, 2015. Physiological responses (stomatal conductance, transpiration rate, chlorophyll content and net photosynthetic rate) to experimental warming varied with the species and the time of the measurement. Stomatal conductance ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) tended to decrease for F. rhynchophylla (Control: $158.97{\pm}42.76$; Warmed: $42.07{\pm}8.24$), Z. serrata (Control: $170.53{\pm}27.22$; Warmed: $101.17{\pm}42.27$) and B. costata (Control: $249.93{\pm}47.39$; Warmed: $150.73{\pm}26.52$). Transpiration rate ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) also decreased for F. rhynchophylla (Control: $4.08{\pm}0.62$; Warmed: $1.74{\pm}0.39$), Z. serrata (Control: $4.32{\pm}0.44$; Warmed: $3.24{\pm}1.14$) and B. costata (Control: $6.21{\pm}0.38$; Warmed: $4.66{\pm}0.28$). However, warming exhibited only minimal effects on stomatal conductance and transpiration rate of Q. variabilis seedlings. Chlorophyll content increased by the warming treatment while the effect of warming was not significant on net photosynthetic rate, since the warming treatment had a weak influence for changing net photosynthetic rate.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.210-218
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• 1991

This study was carried out to investigate the influence of inoculation with Bradyrhizobia and lime types on the nutrient content and yield of peanut. Inoculation size of Bradyrhizobium sp. HCR-46 was $8.2{\times}10^7$ cells per seed. Slaked lime, magnesium lime, and calcium carbonate were applied in an amount required for neutralization of soil. 150kg of calcium sulfate was fertilized to 10a of the experimental field. Sowing space was $40{\times}25cm$ under vinyl mulching. Leaves and stems for assay were sampled at 100 day after sowing. The obrained results are as follows. 1. Number and dry weight of nodule as well as dry weight of aerial part of peanut plant increased by inoculation with B. sp. and were the highest in calcium carbonate application. 2. Inoculated with B. sp., the contents of T-N, $K_2O$, MgO, allantoin, ammonia, free amino acid and chlorophyll increased, but that of nitrate decreased. 3. The contents of T-N, free amino acid, and chlorophyll were higher in the treatment of calcium carbonate, those of $K_2O$, MgO, allantoin, ammonia were higher in magnesium lime application, and those of CaO and nitrate were higher in slaked lime fertilization than any other lime types. 4. Contents of total sugar and starch in stem at 100 days were higher in the treatment of uninoculation than inoculation with B. sp., and those were highest in the calcium sulfate application than the other lime types. 5. Inoculated with B. sp. length of main stem and number of pods increased significantiy. Yield of seed was higher in inoculation with B. sp. than in uninoculation by 64%, and in the order of carbonate, magnesium lime, slaked lime, in calcium sulfate and non-application was the contribution of soil treatments to yield increases.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.571-585
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• 2017

The number of spaceborne optical sensors including red-edge band has been increasing since red-edge band is known to be effective to enhance the information content on biophysical characteristics of vegetation. Considering that the Agriculture and Forestry Satellite is planning to carry an imaging sensor having red-edge band, we tried to analyze the current status and potential of red-edge band. As a case study, we analyzed the effect of using red-edge band and tried to find the optimum band width and wavelength region of the red-edge band to estimate leaf area index (LAI) of very dense tree canopy. Field spectral measurements were conducted from April to October over two tree species (white oak and pitch pine) having high LAI. Using the spectral measurement data, total 355 red-edge bands reflectance were simulated by varying five band width (10 nm, 20 nm, 30 nm, 40 nm, 50 nm) and 71 central wavelength. Two red-edge based spectral indices(NDRE, CIRE) were derived using the simulated red-edge band and compared with the LAI of two tree species. Both NDRE and CIRE showed higher correlation coefficients with the LAI than NDVI. This would be an alternative to overcome the limitation of the NDVI saturation problem that NDVI has not been effective to estimate LAI over very dense canopy situation. There was no significant difference among five band widths of red-edge band in relation to LAI. The highest correlation coefficients were obtained at the red-edge band of center wavelength near the 720 nm for the white oak and 710 nm for the pitch pine. To select the optimum band width and wavelength region of the red-edge band, further studies are necessary to examine the relationship with other biophysical variables, such as chlorophyll, nitrogen, water content, and biomass.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.35-43
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• 2012

The objective of this research was to confirm the difference in physiological responses to environmental stresses such as chilling, high temperature, NaCl, and chemical stress (paraquat) in Protox inhibitor resistant-transgenic rice (MX, PX, and AP37) and its non-transgenic counterpart (WT). Transgenic and non-transgenic rice plants were exposed to a chilling temperature of $5^{\circ}C$ for 1 day or a high temperature of $45^{\circ}C$ for 4 days and allowed to recover at $25^{\circ}C$ for 6 days after the chilling treatment or 8 days after the high temperature treatment. Leaf injury, shoot fresh weight, porphyrin biosynthesis substances, and chlorophyll content were investigated in transgenic and non-transgenic rice at 6 days after 0.5% and 1% NaCl treatments or at 5 days after 0~300 ${\mu}M$ paraquat treatments. No significant difference in leaf injury and shoot fresh weight were observed between transgenic and non-transgenic rice during chilling and recovery. Plant height and shoot fresh weight were also similar between transgenic and non-transgenic rice during the high temperature and recovery period (0~5 days). However, plant height and shoot fresh weight in transgenic rice line MX and PX were lower than in non-transgenic rice at 6 days for recovery. Leaf injury, chlorophyll, and Mg-Proto IX ME contents had no significant difference between transgenic rice and non-transgenic rice after NaCl treatment, but Proto IX content for AP37 and shoot fresh weight for PX and AP37 in 0.5% NaCl treatment were significantly reduced compared with non-transgenic rice. There was no difference in leaf injury and shoot fresh weight when comparing transgenic rice and non-transgenic rice after paraquat treatment. Although transgenic rice and non-transgenic rice showed a little difference at a particular measurement period in certain environmental stresses, there was generally no difference in physiological responses between transgenic rice and non-transgenic rice.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.7-13
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• 1997

Tomatoes are flooded differently 0, 5, 10 and 15 ㎝, according to the developing stages such as transplanting stage under the condition of green house. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. As the depth of flooding got deeper and the hours got longer, plant height, number of leaves, shoot and root decreased significantly. Flowering was possible for 24 hours in the flooding of 0 ㎝, for 6 hours in $5{\sim}10$ ㎝, but not possible after 6 hours in 15 ㎝. Without regard to the depth of flooding, adventitious root came into being before or after 48 hours of the treatment. Root activity diminished gradually as hours of treatment went by, but diminished rapidly over the depth of 5 ㎝. Chlorophyll content decreased similarly as in the case of root activity. Diffusion resistance of stomata cell increased as hours of treatment passed and depth increased. Photosynthesis and respiration diminished according as the hours and depth of treatment increased. Respiration diminished a little gradually but photosynthesis weakened greatly as the depth of treatment became greater and after 48 hours of treatment. Diseases occurred remarkably in proportion to the depth of treatment and the increase of hours. The possibility of preventing by means of insecticide treatment showed the same tendency as in the seedling stage. But its effect was not significant. After 120 hours yields could not be expected because tomatoes died without regard to the depth of flooding. Instead of the depth, numbers of fruits per plant decrease of individuals or variation of average weight of a fruit was recognized. Especially average weight increased in accordance with the increase of the depth. There was positive correlation between all the characters, such as plant height, number of leaves, fresh weight, chlorophyll content, root activity and yield traits, but negative correlation between these and epinastic curvature, diffusion resistance and adventitious root.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.59-66
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• 2020

Recently, cultivation and management technologies have been needed to adapt due to climate change, which is causing abnormal weather conditions. One technique is to increase the utilization of evergreen broad-leaved species with high ornamental value. A total of five treatments were installed (1m×22.5m), including 60g/㎡ and 80g/㎡ using two types mulching material with an overlapping and hole-drilling mulching method and these were compared to un-mulching treatment a total of planted 92㎡ attheWol-aTestSiteForestattheForestforBiomaterialsResearchCenterinJinju-si, Gyeongsangnam-dofor 10monthsusing3-years-oldQuercusglaucaThunb. In comparison with the control site, the 60g/㎡ overlapping method was about 1.9 times higher than the root collar diameter, but there was no statistical significance between the treatments. Healthy seedlings were found to meet these conditions due to high biomass values and below and T/R ratios of 3.0 or lower and H/D ratios of 7.0 or lower. Comparing the values of LWR, SWR, and RWR, which can be evaluated for seedling due to the mulching treatments, as compared to the control, the growth of the ground areas including leaves and stems was enhanced, but the growth of the underground areas containing roots tended to have high control values. Based on this, the SQI value, which can be evaluated for the comprehensive quality of seedlings, was found to be significantly different between the control site and the mulching treatment sites, confirming that the growth and growth improvement effects were achieved with mulching treatments. The chlorophyll content analysis showed that there was a significant difference from the control site, and it was judged that weed generation in the control acted as an environmental stress, causing a decrease in chlorophyll content. It was found that the overlapping 80g/㎡ of polypropylene mulching material generated about 4 times fewer weeds than the control, and the manpower required for the mulching test field and weeding were equal at 3.3 people/100㎡/1 day. Mulching treatments have demonstrated a significant difference in the promotion of growth and quality of the seedlings and are judged as an alternative that can reduce the economic burden incurred by the purchase of the supplies and the manpower required to weed forestry plantations.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.666-672
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• 2017

Hemp [Cannabis sativa L.] has been cultivated as a fiber crop for long history, but it was a good oil crop because its seed contain plenty of lipid which is high ratio of unsaturated fatty acid. Hemp seed oil was extracted with a extruding method in many countries including Europe. The color of oil extracted with extruding method is dark green which could be difficult to attract consumer's interest in Korea because of insufficient information about hemp seed oil. This study was conducted to know correct information about hemp seed oils which were extracted with pressuring and extruding methods. In extruding method, seeds were crushed during the extracting process and discharged oil cake in shape of thin ribbon, but maintained seed shape although the seed were slightly flatted in pressuring method. Oil yield were higher in the extruding method in comparison with pressuring method. The oil have lower degree of lightness but higher degree of greenness and yellowness in the extruding method in comparison with pressuring method because of higher content of chlorophyll A, B and carotenoid. In fatty acid composition, the ratio of palmitic acid, stearic acid, oleic acid and ${\gamma}$-linolenic acid were higher but linoleic acid and ${\alpha}$-linolenic acid were lower in the extruding method in comparison with pressuring method. The content of total tocopherol and ${\gamma}$-tocopherol were lower in the extruding method in comparison with pressuring method.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.26-33
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• 1996

A nutrient solution culture experiment was conducted in the greenhouse at Suwon Campus. Kyung-Hee University from May 23 to July 11. 1995, to determine the effects of potassium application on seedling growth of Kwanganok and Hwengsungok cultivars of corn. Potassium was treated with four different levels, which are 0.248.496 and 744ppm for treatments without potassium (-k), standard potassium concentration (K), double(2k) and triple (3k) of standard potassium concentration, respectively. Plants were harvested at weekly interval for seven weeks. at which time plant height, leaf area and dry matter yield of corn seedling were measured, only chlorophyll content was taken for five weeks from three week after planting. Seedlings growth of Kwanganok and Hwengsungok cultivars was greatly retarded from planting to harvesting time in 3k treatment. The plant height, leaf area and dry matter yield of both cultivars during the whole period were decreased in order of K>2F>-K>3K, but dry matter yield of Kwanganok cultivar was decreased in order of 2K>K>-K>3K. Chlorophyll content of Kwanganok and Hwengsungok cultivars was irregularly fluctuated during growing period. but generally highest in K treatment and lowest in 3k treatment. The crop growth rates of seedlings of both cultivars were slow until the 3rd week after planting. but very fast thereafter. In general, CGR of both cultivars was higher in K and 2k treatments than -k and 3k treatments.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.143-150
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• 2017

Effects of packaging methods for maintaining the shelf-life and postharvest quality of Korean chive (Allium tuberosum Rotter) usually called buchu in Korea was studied during fall season. Buchu, which has high moisture content and active metabolism after harvest, is characterized by the greater changes in quality during storage and distribution. It is usually packaged in paper box during distribution in domestic channel in Korea where the marketability ends within few days of harvest. In order to maintain the commercial quality of buchu, we tried to use inner film with or without absorbent paper in commercial paper box packaging. The 'Greenbelt' cultivar of buchu was harvested in october and packaged in corrugated paper box (A), in corrugated paper box with micro-perforated high density polyethylene (HDPE) film as inner material (B), a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (C) and a combination of HDPE film as inner material along with a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (D), and stored at $5^{\circ}C$ for up to 21 days. Several quality parameters such as fresh weight loss, respiration rate, color, chlorophyll content and sensory qualities were monitored during storage. When buchu was packaged only in paper box, the appearance and quality deteriorated rapidly through decay development thereby sample became unmarketable within 12 days. On the other hand, buchu packaged with inner HDPE film maintained its quality, good visual appearance and exhibited a longer period of marketable life compared to the samples stored in other treatments. However, the use of absorbent paper did not have any significant effect in maintaining quality of buchu. The uses of inner HDPE film was effective in reducing weight loss that resulted better visual appearance of buchu. Results suggest that the use of inner HDPE film in bulk type corrugated paper box packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of buchu. Further investigation on other quality parameters and packaging methods would be useful in maintaining the quality aspects of buchu at postharvest stages.