• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.355-360
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• 2013

Diesel-burning air heater (air heater) and infrared heating lamp (infrared heater) were installed as auxiliary heaters in two single water-curtained plastic greenhouses with a set night temperature of $6^{\circ}C$ for cultivation of strawberry 'Seolhyang'. The average night air temperature was $6.6^{\circ}C$ in the infrared heater treatment and $7.1^{\circ}C$ in the air heater treatment. However, when the minimum outside temperature fell below $-10^{\circ}C$, the air heater had less internal temperature fluctuations. In contrast, the infrared heater had some cases of falling below the set temperature. The relative humidity was higher than 98% by the side-effect of water-curtain system regardless of the heating system. There was about $5^{\circ}C$ difference in leaf temperature between the turned-on and -off state of the infrared heater, and the efficacy of the infrared heater on leaf temperature was only limited to about 4 meters from the system. Peduncle length and plant height in the infrared heater tended to be greater than those in the air heater. There was, however, no statistically difference in leaf size and numbers of leaves, flowers on first cluster and branches. There was no difference in soluble solids content, fruit firmness, average fruit weight of the harvested fruits, and the yield. Comparing the heating costs, the air heater system took 622,662 won based on 543 L tax-free diesel, while the infrared heater system took 235,284 won by consuming 5,685 kWh of electricity, and 62.2% heating costs saving was achieved.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.55-60
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• 2013

BACKGROUND: The buds of persimmon trees are susceptible to cold damage, often with the late frost, at the time of budburst. This study was conducted to determine effect of the cold damage on shoot and fruit growth the current season. METHODS AND RESULTS: 'Fuyu' trees, grown in 50-L pots, were placed for 1 h at $-2.2{\pm}0.5$, $-2.6{\pm}0.5$, or $-3.0{\pm}0.5^{\circ}C$ within a cold storage, at their budburst on April 5. Some trees under ambient temperature at $10-17^{\circ}C$ served as the control. Cold damage of the buds containing flower buds was 54% at $-2.2^{\circ}C$, and significantly increased to 95% at $-3.0^{\circ}C$. The bud damage included the complete death of all, complete death of main buds only, or the late and deformed shoot growth in the spring. Number of flower buds in early May dramatically decreased as the damage ratio increased. Since the thinning of flower buds in mid-May and fruitlets in early July was done in no or slightly damaged trees, the final number of fruits and yield did not decrease compared with the control when the damage increased by 60% and 70%, respectively. Average fruit weight and skin coloration tended to be better with increasing bud damage. Shoot growth was more vigorous in those trees whose buds were severely damaged by low temperature. CONCLUSION(S): Shoot growth and the yield may depend on the number of flower buds and percent fruit set after the cold damage.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.266-274
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• 2010

This study aim to investigate fundamentally the growth and physiological responses of tomato plants in responses to two different levels of water deficit, a weak drought stress (-25 kPa) and a severe drought stress (-100 kPa) in soil. The two levels of water deficit were maintained using a micro-irrigation system consisted of soil sensors for the real-time monitoring of soil water content and irrigation modules in a greenhouse experiment. Soil water contents were fluctuated throughout the 30 days treatment period but differed between the two treatments with the average -47 kPa in -25 kPa set treatment and the -119 kPa in -100 kPa set treatment. There were significant differences in plant height between the two different soil water statuses in plant height without differences of the number of nodes. The plants grown in the severe water-deficit treatment had greater accumulation of biomass than the plants in the weak water-deficit treatment. The severe water-deficit treatment (-119 kPa) also induced greater leaf area and leaf dry weight of the plants than the weak water-deficit treatment did, even though there was no difference in leaf area per unit dry weight. These results of growth parameters tested in this study indicate that the severe drought could cause an adaptation of tomato plants to the drought stress with the enhancement of biomass and leaf expansion without changes of leaf thickness. Greater relative water content of leaves and lower osmotic potential of sap expressed from turgid leaves were recorded in the severe water deficit treatment than in the weak water deficit treatment. This finding also postulated physiological adaptation to be better water status under drought stress. The drought imposition affected significantly on photosynthesis, water use efficiency and stomatal conductance of tomato plants. The severe water-deficit treatment increased PSII activities and water use efficiency, but decreased stomatal conductance than the weak water-deficit treatment. However, there were no differences between the two treatments in total photosynthetic capacity. Finally, there were no differences in the number and biomass of fruits. These results suggested that tomato plants have an ability to make adaptation to water deficit conditions through changes in leaf morphology, osmotic potentials, and water use efficiency as well as PSII activity. These adaptation responses should be considered in the screening of drought tolerance of tomato plants.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.25-31
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• 2012

This study aimed to investigate the effect of night temperature on the productivity, growth, and fruit characteristics of tomatoes and set the optimal night air temperature. Tomatoes (Solanum lycopersicum Mill. cv. Superdoterang and cv. Rapito) were grown at 5, 10, 15, and $20^{\circ}C$ during night time and ventilation temperature point during day time set $27^{\circ}C$. Depending on night air temperature, plant height, leaf area, fresh and dry weight of each organ, leaf, stem, and root were changed. Condition of high night temperature resulted in promotion of tomatoes growth with high dry weight and fresh weight. However, the dry weight under night temperature $20^{\circ}C$ decreased, especially, in 'Superdoterang'. On changes of yield, 'Rapito' showed higher productivity than 'Superdoterang' and the highest productivity point for nigh temperature is $13.32^{\circ}C$ for 'Superdoterang' and $14.25^{\circ}C$ for 'Rapito'. Although the total yield decreased from the point, the daily productivity increased with increasing night temperature, the highest point for nigh temperature is $14.45^{\circ}C$ for 'Superdoterang' and $16.46^{\circ}C$ for 'Rapito'. High temperature deceased the fruit weight and increased total soluble solid content in fruits. It is concluded that the night air temperature changes productivity of tomato and the temperatures between productivity and growth velocity have differences depending on different cultivars. scores than the other beef jerky samples (p<0.05).

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.438-446
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• 2019

The interest in mini watermelon (Citrullus lanatus) with small fruits weighing 2-3 kg has increased by the increasing trend in one-person households and consequent tendency to consume small meals. Watermelon grafting onto cucurbit rootstocks is a very effective way to control soil-borne diseases, such as Fusarium wilt; however, this practice negatively impacts the fruit quality. This study was conducted to investigate the growth, fruit set, and fruit quality of mini watermelon grafted onto wild watermelon accessions (Citrullus spp.) resistant to Fusarium wilt. Five watermelon accessions (Galactica, IT 208441, PI 482322, PI 500303, and PI 593358) were evaluated as rootstocks for the mini watermelon "Ministar". Non-grafted "Ministar" and "Ministar" grafted onto "Shintozwa" (Cucurbita maxima D. C. moschata D.) or "Bullojangsaeng" (Lagenaria leucantha) were used as controls. The roots of the transplants grafted onto "PI 593358" and "Shintozwa" weighed more than those on other rootstocks. Additionally, the transplants on "PI 593358" showed better growth and fruit set in the field than the other transplants. However, the total soluble solid contents and fruit quality indices of the transplants on "PI 593358" and "Shintozwa" were lower, whereas the total fruit quality index of those on "PI 482322" was higher. Thus, the wild watermelon accessions tested can potentially be used as basic germplasm for developing watermelon rootstocks instead of cucurbit rootstocks. The most promising accession for this purpose was found to be "PI 482322".

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.444-451
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• 2022

Recently, long-term cultivation is becoming more common with the increase in tomato hydroponics. In hydroponics, it is very important to supply an appropriate nutrient solution considering the nutrient and moisture requirements of crops, in terms of productivity, resource use, and environmental conservation. Since seasonal environmental changes appear severely in long-term cultivation, it is so critical to manage irrigation control considering these changes. Therefore, this study was carried out to investigate the effect of irrigation volume on growth and yield in tomato long-term cultivation using coir substrate. The irrigation volume was adjusted at 4 levels (high, medium high, medium low and low) by different irrigation frequency. Irrigation scheduling (frequency) was controlled based on solar radiation which measured by radiation sensor installed outside the greenhouse and performed whenever accumulated solar radiation energy reached set value. Set value of integrated solar radiation was changed by the growing season. The results revealed that the higher irrigation volume caused the higher drainage rate, which could prevent the EC of drainage from rising excessively. As the cultivation period elapsed, the EC of the drainage increased. And the lower irrigation volume supplied, the more the increase in EC of the drainage. Plant length was shorter in the low irrigation volume treatment compared to the other treatments. But irrigation volume did not affect the number of nodes and fruit clusters. The number of fruit settings was not significantly affected by the irrigation volume in general, but high irrigation volume significantly decreased fruit setting and yield of the 12-15th cluster developed during low temperature period. Blossom-end rot occurred early with a high incidence rate in the low irrigation volume treatment group. The highest weight fruits was obtained from the high irrigation treatment group, while the medium high treatment group had the highest total yield. As a result of the experiment, it could be confirmed the effect of irrigation amount on the nutrient and moisture stabilization in the root zone and yield, in addition to the importance of proper irrigation control when cultivating tomato plants hydroponically using coir substrate. Therefore, it is necessary to continue the research on this topic, as it is judged that the precise irrigation control algorithm based on root zone-information applied to the integrated environmental control system, will contribute to the improvement of crop productivity as well as the development of hydroponics control techniques.

• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.193-206
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• 2014

The objectives of the project are to increase farmers' income through GAP and to reduce the loss of agricultural produce, for which the Korean partner takes a role of transferring needed technologies to the project site. To accomplish the project plan, it is set to implement the project with six components: construction of buildings, installation of agricultural facilities, establishment of demonstration farms, dispatching experts, conducting training program in Korea and provision of equipments. The Project Management Committee and the Project Implementation Team are consisted of Korean experts and senior officials from Department of Agriculture, Myanmar that managed the project systematically to ensure the success of the project. The process of the project are; the ceremony of laying the foundation and commencing the construction of training center in April, 2012. The Ribbon Cutting Ceremony for the completion of GAP Training Center was successfully held under PMC (MOAI, GAPI/ARDC) arrangement in SAl, Naypyitaw on June 17, 2012. The Chairman of GAPI, Dr. Sang Mu Lee, Director General U Kyaw Win of DOA, officials and staff members from Korea and Myanmar, teachers and students from SAl attended the ceremony. The team carried out an inspection and fixing donors' plates on donated project machineries, agro-equipments, vehicles, computers and printer, furniture, tools and so forth. Demonstration farm for paddy rice, fruits and vegetables was laid out in April, 2012. Twenty nine Korean rice varieties and many Korean vegetable varieties were introduced into GAP Project farm to check the suitability of the varieties under Myanmar growing conditions. Paddy was cultivated three times in DAR and twice in SAl. In June 2012, vinyl houses were started to be constructed for raising seedlings and finished in December 2012. Fruit orchard for mango, longan and dragon fruit was established in June, 2012. Vegetables were grown until successful harvest and the harvested produce was used for panel testing and distribution in January 2013. Machineries for postharvest handling systems were imported in November 2012. Setting the washing line for vegetables were finished and the system as run for testing in June 2013. New water tanks, pine lines, pump house and electricity were set up in October 2013.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.243-246
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• 2012

The study was aimed at the development of the simple linear regression model to estimate the fruit yield of sweet pepper and to support decision-making management for growing sweet pepper crop in Korea. For quantitative analysis of relationship between environmental data and periodical yield of sweet pepper the data obtained from the commercial Venlo-type glasshouse for 2 years. Obtained periodical yield data of five different cultivars and radiation data were accumulated and fitted by linear regression. A significant linear relationship was found between radiation integral and fruit yield, whereas the production per unit of radiation was different between cultivars. The slope of linear regression could indicate as light use efficiency for fruit production ($LUE_F$, $g{\cdot}MJ^{-1}$). $LUE_F$ of 'Ferrari' was $5.85g{\cdot}MJ^{-1}$, 'Fiesta' 5.32 for first year and $4.75g{\cdot}MJ^{-1}$ and for second year, 'President' was $4.66g{\cdot}MJ^{-1}$, 'Cupra' was $3.86g{\cdot}MJ^{-1}$, and 'Boogie' was $6.48g{\cdot}MJ^{-1}$. The amount of light requirement for the unit gram of fruit was between $25.88J{\cdot}g^{-1}$, for 'Cupra' and $15.42J{\cdot}g^{-1}$ for 'Boogie'. Although we found the linear relationship between radiation and fruit yield, $LUE_F$ was varied between cultivars and as well as year. The linear relationship could describe the fruit yield as function of radiation, but it needed more variable to generalization of the production, such as cultivar specifications, temperature, and number of fruits set per plant or unit of ground.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.349-354
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• 2013

This study examined a technique for cooling root zone aimed at lowering substrate temperature for sweet pepper (Capsicum annum L. 'Orange glory') cultivation in coir substrate hydroponics during hot season, from the $16^{th}$ of July to $15^{th}$ of October in 2012. The root zone cooling technique was applied by using an air duct (${\varnothing}12$ cm, hole size 0.1 mm) to blow cool air between two slabs during night (5p.m. to 3a.m.). Between the $23^{rd}$ of July and $31^{st}$ of August (hot temperature period), average daily substrate temperature was $24.7^{\circ}C$ under the root zone cooling, whereas it was $28.2^{\circ}C$ under condition of no cooling (control). In sunny day (600~700 W $m^{-2}{\cdot}s^{-1}$), average substrate temperatures during the day (6a.m. to 8p.m.) and night (8p.m. to 6a.m.) were lower about $1.7^{\circ}C$ and $3.3^{\circ}C$, respectively, under the cooling treatment, compared to that of control. The degree of temperature reduction in the substrate was averagely $0.5^{\circ}C$ per hour under the cooling treatment during 6p.m. to 8p.m.; however, there was no decrease in the temperature under the control. The temperature difference between the cooling and control treatments was $1.3^{\circ}C$ and $0.6^{\circ}C$ in the upper and lower part of the slab, respectively. During the hot temperature period, about 32.5% reduction in the substrate temperature was observed under the cooling treatment, compared to the control. Photosynthesis, transpiration rate, and leaf water potential of plants grown under the cooling treatment were significantly higher than those under the control. The first flowering date in the cooling was faster about 4 days than in the control. Also, the number of fruits was significantly higher than that in the control. No differences in plant height, stem thickness, number of internode, and leaf width were found between the plants grown under the cooling and control, except for the leaf length with a shorter length under the cooling treatment. However, root zone cooling influenced negligibly on eliminating delay in fruiting caused by excessively higher air temperature (> $28^{\circ}C$), although the substrate temperature was reduced by $3^{\circ}C$ to $5.6^{\circ}C$. These results suggest that the technique of lowering substrate temperature by using air-duct blow needs to be incorporated into the lowering growing temperature system for growth and fruit set of health paprika.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.739-751
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• 2015

This study investigated the table settings used in Bul-chun-wi sacrificial rituals in Sangju, Gyeongpook Province. This study took place from May 2014 to April 2015 and incorporated field research and literature review. The subjects of the study were Sojae jongga (family head), Wolgan jongga, Ubook jongga and Ipjae jongga. There were four rows in the table setting of the Wolgan, whereas there were five rows in the other jonggas. In row 5, there were fruits, seeds and confections. In row 4, there were vegetables. In row 3, there was tang (stew); in row 2, juk (steamed meats or fishes) and pyun (rice cake); and in row 1, meh (boiled rice), geng (soup) and myun (noodles). The common food setting was arranged in the order of meh, geng, myun, ganjang (Korean soy sauce), poh (dried meat/fish), chimchae (water kimchi), dates, chestnuts, pears, persimmons, walnuts, bracken, bellflowers, croaker, pyun, and ssam (rice wrapped in lettuce leaves). Ubook jongga had the most number of stews at seven. Sojae and Ipjae jongga each had five stews, and Wolgan jongga had three. The smaller Wolgan jongga had gehjuk (boiled chicken), uhjuk (steamed fish) and yookjuk (boiled meat) arranged in a neat pile on one dish used for rituals, whereas Ubook jongga had gehjuk, uhjuk and yookjuk arranged separately. Sojae and Ipjae jongga had gehjuk arranged separately while yookjuk and uhjuk were arranged as dojuk (gehjuk, uhjuk, yookjuk). The uhjuk was arranged separately. In Wolgan jongga, po was arranged on the right while in the other jonggas, it was arranged to the left. For raw meat Ubook jongga, raw mackerel; Ipjae jongga, raw croaker, and Sojae jongga Yukhoe (beef tartare) were set. However, pork, chicken and croaker were cooked. Other ritual food were used in seasoning and boiling. In the geng Wolgan and Ipjae jongga used miyeokguk (seawood soup), whereas Sojae and Ubook jongga used tangguk (meat soup with vegetables). For the ritual food, most jongga ordered yoogwa, yakgwa and bonpyun as one part, rice cakes (steamed rice cake, glutinous rice cake, jeungpyun, gyungdan), and jehju (alcohol). The other ritual food was prepared on the day by jongga.