• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.2
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• pp.105-114
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• 2018

The aim of this study was to evaluate the change of phenolic compounds after phosphite treatment on Cheorwon onion. Onion is a perennial plant belonging to the lily family. It is native to Persia of Southwest Asia. It is widely cultivated in the temperate regions of the world. Onion is a good name for the 'Okchong' to drop blood cholesterol and cardiovascular blood flow to increase the prevention of adult diseases. Cheorwon area is inland, but it has high continental climate due to its high altitude. Therefore it is said that the onion cultivated in this region has higher sugar content and higher taste than onion grown in the southern region. Phosphorus components are particularly important ingredients for promoting muscle development. However, if the phosphoric acid content of the soil part is maintained to a large extent until the harvest, the competition of the nutrients tends to cause decay of the root part. Therefore, it is important to improve the quality and shelf life of onion by inducing nutrient balance by applying foliar fertilization method on the reducing phosphorus at harvest time. In this study, acidity was controlled by diluting phosphorous acid(H₃PO₃) and potassium hydroxide(KOH), followed by leaf surface treatment with phosphite on onion. In this study, the concentration of phosphite was diluted to 500, 1,000, 1,500ppm and sprayed three times over the onion leaves in May 2018 using an atomizer and harvested at the end of June, and the phenolic compounds were analyzed by HPLC. As a result, the content of quercetin, one of the important substances in onion, was phosphite 500ppm(179.70㎍/g), 1,000(150.27), 1,500(105.95). The contents of caffeic acid, p-coumaric acid, ferulic acid, rutin, kaempferol, and sugar content were higher in the treatments than in the control. Therefore, the phosphite does not have a great influence on the growth, but it may play a role as a method of achieving balance with nitrogen in the rainy season by supplying the role of the material catalyst and the water soluble phosphoric acid and the potassium in the influence of the material change.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.62-62
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• 2020

Ginseng is a shade-plant cultivated using shading facilities. However, at too low light levels, root growth is poor, and at high light levels, the destruction of chlorophyll reduces the photosynthesis efficiency due to leaf burn and early fall leaves. The ginseng has a lightsaturation point of 12,000~15,000 lux when grown at 15 to 20℃ and 9,500 lux at 25℃. This study was conducted to select the optimal light intensity of 3-year-old ginseng grown in blue-white film plastic house. The seeds were planted in the blue-white film plastic house with different light receiving rate (March 17, 2020). Between April and September, the average air temperature in the house was 20.4-20.7℃. Average soil temperature was 18.3℃-18.5℃. The chemical properties of the test soil was as follows. The pH level was 7.0-7.4, EC was 0.5-0.6 dS/m, OM was at the levels of 33.6-37.7 g/kg, P₂O₅ was 513.0-590.8 mg/kg, slightly higher than the allowable 400 mg/kg. The amount of light intensity, illuminance, and solar radiation in the blue-white film house was increased as the light-receiving rate increased and the amount of light intensity was found to be 9-14% compared to the open field, 8-13% illuminance and 9-14% solar irradiation respectively. The photosynthesis rate was the lowest at 3.1 µmolCO²/m²/s in the 9% light blue-white plastic house and 4.2 and 4.0 µmolCO²/m²/s in the 12% and 14% light blue-white plastic house, respectively. These results generally indicate that the photosynthesis of plants increases with the amount of light, but the ginseng has a lower light saturation point at high temperatures, and the higher the amount of light, the lower the photosynthetic efficiency. The SPAD (chlorophyll content) value decreased as the increase of light-receiving rate, and was the highest at 32.7 in 9% light blue-white plastic house. Ginseng germination started on April 11 and took 13-15 days to germinate. The overall germination rate was 82.9-85.8%. The plant height and length of stem were long in the 9% light-receiving plastic house. The diameter of stem was thick in the 12-14% light-receiving plastic house. In the 12% and 14% light-receiving plastic house, the length and diameter of taproot was long and thick, so the fresh weight of root per plant was 20 g or more, which was heavier than 16.9 g of the 9% light-receiving plastic house. The disease incidence (Alternaria blight, Gray mold and Damping-off etc.) rate were 0.9-2.7%. The incidence of Sclerotinia rot disease was 7.5-8.4%, and root rot was 0-20.0%. The incidence ratio of rusty root ginseng was 34.4-38.7% level, which was an increase from the previous year's 15% level.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.2
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• pp.21-38
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• 2024

This study aims to establish an efficient street green area to improve the urban thermal environment and enhance pedestrian thermal comfort. Specifically, This study identified parameters applicable to green space planning and design, analyzed thermal environment mitigation mechanisms for each parameter, and, based on these findings, proposed methods for tree species selection and planting in green space planning and design. To achieve this, 61 papers were selected through a four-stage process from both domestic and foreign sources. The selected papers were analyzed, and the following main results were derived: In open street canyons with high stress levels due to low aspect ratios and high sky view factors(SVF), broadleaf trees with wide crown widths, low trunk heights, high leaf area index(LAI), and high crown heights were found effective in reducing heat, thereby increasing the amount and quality of shade. In contrast, in deep and narrow street canyons with relatively low heat stress due to high aspect ratios and low SVF, broad-leaved trees with narrow crown widths, high trunks, low crown heights, and low LAI were effective in reducing heat by enhancing ventilation. This study can serve as fundamental data for establishing standards for street green spaces to improve the thermal environment of street canyons and enhance thermal comfort of pedestrians. Additionally, it can be valuable when selecting the location and prioritizing street green spaces. Moreover, it is anticipated to be a foundational resource for creating guidelines for green space planning and design in response to climate change.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.4
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• pp.370-375
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• 2016

The purpose of development new variety 'Miho' (Hordeum vulgare L.) is a favorite with livestock feed and develop varieties resistant to disease and lodging. 'Miho' was carrying out the growth habit of group III with green and mid-wide leaf. Awn that is related to preference of livestock is a semi-smooth awn. This cultivar had 96 cm of culm length, 650 of spikes $per\;m^2$. Heading date of 'Miho' was April 27, and maturing date on May 30, which were later than cultivar 'Youngyang'. It also showed strong winter hardiness, and similar resistance to shattering and bariy yellow mosaic virus (BaYMV) compared with those of check one. The best thing among the traits of a good quality with the plant green at the latter growing period. The average forage dry matter yield in the regional yield trial was about 13.1, 12.1 MT per ha in upland and paddy field, respectively, which were 9%, 2% higher than that of the check cultivar. It's also showed 6.8% crude protein, 27.1% ADF (acid detergent fiber), and 67.5% TDN (total digestible nutrients), including higher silage quality for whole crop barley. This cultivar would be suitable for the area whose average minimum temperature was above $-8^{\circ}C$ January in Korean peninsula.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.193-200
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• 2013

BACKGROUND: Plant factory system of an artificial light type using Light-Emitting Diodes (LEDs), fluorescent light, or metal halide lamp instead of sun light is an ultimated method for plant production without any pesticides regardless of seasonal changes. The plant factory is also completely isolated from outside environmental conditions such as a light, temperature, or humidity compared to conventional greenhouse. Light-environment control such as a quality or quantity in the plant factory system is essential for improving the growth and development of plant species. However, there was little report that the effects of various light qualities provided by LEDs on Ledebouriella seseloides growth under the plant factory system. METHODS AND RESULTS: Ledebouriella seseloides seedlings transplanted at urethane sponge were grown in the plant factory system of a horizontal type with LED artificial lights for 90 days. Yamazaki solution for hydroponic culture of the seedlings was regularly irrigated by the deep flow technique (DFT) system on the culture gutters. Electrical Conductivity (EC) and pH of the solution was recorded at 1.4 ds/m and 5.8 in average, respectively during the experimental period. Number of unfolded leaves, leaf length, shoot fresh and dry weight of the seedlings were three times measured in every 30 days after beginning of the experiment. Blue LEDs, red LEDs, and fluorescent lights inside the plant factory were used as light sources. Conventional fluorescent lamps were considered as a control. In all the treatment, light intensity was maintained at $100{\mu}mol/m^2/s$ on the culture bed. Fresh weight of the seedlings was 3.7 times greater in the treatment with the mixture radiation of fluorescent light and blue+red LEDs (1:3 in energy ratio; Treatment FLBR13) than in fluorescent light treatment (Treatment FL). In FLBR13 treatment, dry weight per seedling was two times greater than in FL or BR11 treatment of blue+red LEDs (1:3 in energy ratio; Treatment BR11) during the culture period. Increasing in number of unfolded leaves was also significantly affected by the FLBR13 treatment comparing with BR11 treatment. CONCLUSION(S): Hydroponic culture of Ledebouriella seseloides seedlings was successfully achieved in the plant factory system with mixture lights of blue, red LEDs and fluorescent lights. Shoot growth of the seedlings was significantly promoted by the FLBR13 with the mixture radiation of fluorescent light, blue, and red LEDs under 1:3 mixture ratio of blue and red LEDs during the experimental period compared to conventional light conditions.

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.211-215
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• 2011

This study aimed to determine optimum leaves per shoot in 'Campbell Early' grape through investigating changes of fruit quality after veraison 70~75 berries of first cluster and 35~40 berries of second cluster at 30 days after full bloom. Soluble solids content (SSC) increased dramatically during 28 days after veraison and afterwards it was stabilized. 15 leaves per shoot treatment showed fast increase of SSC from early veraison and reached to over 16.0oBx at 28 days after veraison. No considerable increase of SSC were occurred on either 5 or 0 leaves per shoot treatments after veraison. Titratable acidity (TA) was decreased continuously during 28 days of berry ripening in the all treatments. In 15 leaves per shoot treatment, TA decreased fast during first 7 days after veraison and continuously decreased to 0.5% by harvest time. While, 5 and 0 leaves per shoot treatments showed TA decrease slightly only at the early veraison. Hunter L and b values of 15 leaves per shoot treatment decreased fast during first 7 days of veraison, and gradually decreased by 14 days, whereas Hunter a value increased fast during the first 7 days from veraison. Total anthocyanin content in 15 leaves per shoot treatment increased fast from 7 days of veraison and the increase became slow after 28 days of veraison. Other treatments showed no significant difference from veraison to harvest time.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.35-53
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• 1974

A series of experiment was conducted to investigate the effects of the level of dietary Protein (soybean meal) and carbohydrate (sucrose) on the growth rate, feed efficiency, nutrients digestibility and amylase activity of larvae at 5th instar. The results obtained from the experimentation are summarized as follow： (1) It was found that the body weight gain, cocoon quality and feed efficiency of the 5th instar larvae were significantly affected by the level of protein and carbohydrate in the artificial diet. Present data revealed that the proper level of dietary protein and carbohydrate would be the most important factor for the optimum growth of larvae. (2) In the amount of diet consumption, the group of larvae gained more body weight consumed more diet than the group gained less amount of body weight. (3) Digestibility of nutrients was improved as the level of protein in the diet increased, although the level of dietary carbohydrate did not exert any positive results. (4) It was observed that the amylase activity in digestive juice was stimulated by the increasement of dietary carbohydrate. However, no correlation between the level of dietary protein and carbohydrate was detected in the amylase activity. (5) Analytical data indicated that the amount of protein or carbohydrate excreted through feces and urine was proportional to the content of protein or carbohydrate in artificial diet. The group o( larvae consumed the diet contained high protein excreted more protein and less nitrogen free extract than did the group received low protein diet. Likewise, the group of larvae fed high dietary carbohydrate excreted more nitrogen free extract and less protein through excreta than the group consumed low carbohydrate diet group. (6) Although the amylase activity of the larvae received the artificial diet was higher than the larvae received natural diet (mulberry leaf), the rate of body weight gam and the quality of cocoon produced from the natural diet group was better than the artificial diet group. It is, thus, concluded that feeding the larvae by the artificial diet may net be recommendable. (7) It was determined that the best level of protein (soybean meal) and carbohydrate (sucrose) in artificial diet was found to be 40g and 0g, respectively when it was fed to the 5th instar larvae. (8) It may be concluded from the results obtained that the artificial diet that could stimulate the activity of amylase nay not be recommendable for the practical larvae feeding Purpose due simply to the Poor economic return from this diet than natural diet.

• Asian Journal of Turfgrass Science
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• v.17 no.4
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• pp.155-163
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• 2003

This study was conducted to find out suitable rootzone profile, irrigation system, and turfgrass species for roof turf garden. Treatments of profile with soil amendment were Mixture I: Perlite(PL)60％＋Vermiculite(VC)20％＋Peatmoss(PM)20％, Mixture II: PL60％＋VC 10％＋PM20％＋Sand(SD)10％, Mixture III: PL60％＋VC20％＋PM20％ and Mixture IV: PL60％＋VC10％＋PM20％＋SD10％＋Styrofoam 5cm as a drain layer. To test trickle irrigation for roof garden, intervals of main pipe spacing(50cm, 100cm) and drop hole distance(15, 20, 30, 50 and 100cm)were treated, To select most suitable turfgrass species or mixture, Bermudagrass 'Konwoo', Zoysiagrass 'Konhee' and cool-season grass(Kentucky Bluegrass 80％ ＋ Perennial Ryegrass 20％, Tall Fescue 30％ ＋ KB50％ ＋ PR 20％)were tested. In particle size analysis, the soil amendments Perlite and vermiculite showed very even distribution, however, peatmoss contained mostly coarse particles with fiber over $\Phi$ 4.75mm. Under field moisture condition, vermiculite and peatmoss showed 350％ water holding capacity, on the other hand, sand or Perlite showed 115％ and 166％, respectively. Total weight of soil profile was 139.2kg/$m^2$ with Styrofoam drain layer without sand, which showed most lightest among treatments. Turf quality also resulted positve with Styrofoam drain layer installation. On trickle irrigation system, the proper interval of main drain pipe spacing and drop hole distance were 50cm and 50cm, respectively, In irrigation frequency, once per a day for 15 minute irrigation with 2 1/hr showed the best results on turf quality. Among turfgrass species or cool season grass mixture, warm season turfgrass fine leaf type zoysiagrass 'Konhee' and Bermudagrass 'Konwoo' showed very acceptable result on all over the treatments of rootzone and irrigation system. To apply cool season grasses for the roof garden, advanced researches may be needed to establish the proper soil amendment, rootzone profile, and irrigation system, Application of Bermudagrass 'Konwoo' for roof turf garden also needs successive tests to overcome winter injuries.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.1-8
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• 2009

The greatest and major cost for cut rose production during winter seasons in Korea is cost of heating the greenhouse. A study was conducted on a cost-efficient heating system to reduce expenses of cut rose growers in times of high energy prices. An infrared heating system utilizing radiant energy has an obvious advantage over other heating methods in that the energy is first used to raise temperatures of plants and other objects and subsequently that of the atmosphere, resulting in faster reaching to desired plant temperatures at a reduced heating cost. In this study the heating effect and heating cost saving of a nano-carbon fiber infrared heating system (NCFIHS) installed in cut rose greenhouses in Gimhae, Gyeongnam Province were analyzed comparatively. In addition growth, quality, and vase life of 'Orange Fresh' roses grown in greenhouses heated by NCFIHS against those grown in greenhouses heated by so called an electrical heating system. In greenhouses with a NCFlHS with a set point air temperature of $20^{\circ}C$, plant temperature was maintained at $1{\sim}2^{\circ}C$ higher than the air temperature, and temperatures of growing bed surface and root zone were maintained at $17{\sim}19^{\circ}C$ throughout cold winter nights. The cost for heating in NCFIHS was about 25 and 51% of that of an electrical heating system and a hot water heating system heated by petroleum, respectively. Growth of roses harvested in greenhouses with a NCFIHS was similar to those grown in greenhouses with an electrical heating system. However, cut roses with more intense petal and leaf colors and a longer vase life (fresh weight and amount of water uptake) were harvested in greenhouses with a NCFIHS as compared to those harvested in greenhouses with an electrical heating system.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.276-283
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• 2006

To evaluate the effectiveness of the foliar spray of calcium on "Baekdo" peach fruit, we carried out experiments in the orchards. The sprays were applied with $CaCl_2\;(Ca:\;400mg.kg^{-1})\;and\;CaCl_2$ with adjuvants (amino acid, $2g.kg^{-1}$; phytic acid, $2ml.kg^{-1}$ and wood vinegar, $2ml.kg^{-1}$) for four times from June 12 through July 4 at weekly intervals. The fruits and leaves were evaluated for Ca content, firmness and incidence of Brown rot caused by Monilinia fructicola at harvest To evaluate fruit quality included Ca content, firmness natural decay during the storage, the fruits were stored at room temperature for 14 days. The Ca content in leaf and fruit flesh at harvest was significantly increased (P=0.05) in $CaCl_2$ + amino acid treatment among $CaCl_2$ treatments. However, there was not significant Ca content in fruit peel. The firmness of flesh increased significantly (P=0.05) in $CaCl_2$ + amino acid treatment. The natural decay (Rhizopus stolonifers) during storage at the room temperature for 14 days, the fruit treated with $CaCl_2$ + wood vinegar exhibited lowest (P=0.05) incidence. Also, the firmness of the fruit during storage was firmer with treated $CaCl_2$ than untreated fruit. In the treatments of $CaCl_2$ + phytic acid and $CaCl_2$ + amino acid, it was possible to reduce incidence of Brown rot caused by M. fructicola most effectively in the field. In addition, inoculation with M. fructicola in fruits was also the most effective treatment for inhibiting disease development in vitro. These results suggested that the foliar spray of $CaCl_2$ with adjuvants increased the content of Ca and firmness of the fruits positively. It also inhibited the natural decay and the Brown rot effectively.