• Sijohaknonchong
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• v.25
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• pp.101-127
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• 2006

JANG-YOOK-DANG(장육당) is the pen-name of Lee, Byeol(이별). His elder brother is Lee, won(이원). He was putted to death by the king Yeon-san(연산군). So abandoning the way of the world, JANG-YOOK-DANG hided himself at mountain valley in Peong-san of Hwng-haedo(황해도 평산). Here he angled for fish and with the persons over sixty years old drunk, sang the songs. Then he composed the poem . This poem spreaded abroad, and came to the ears of Lee, Hwang(이황). He criticized this poem to have irreverence by casting upon the world, not to have gentleness and affability. But imitating the poem he composed intended to be sung. For that gentleness and affability are the instruction of the Poetry, he filled the poems with contents of the gentleness and the affability. But the livings of the two persons were different, and then their poems was intended to be sung were different. In these different contents, we can not say that this or that is right. JANG-YOOK-DANG would do to express his bitter sentiments by his song.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.591-597
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• 2015

We determined the total C and N stocks in trees and soils after 1 year of fertilization in an experimental orchard with 16-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees planted at $5.0m{\times}3.0m$ spacing on a Tatura trellis system. Pear trees were fertilized at the rate of 200 kg N, 130 kg P and $180kg\;K\;ha^{-1}$. At the sampling time (August 2013), trees were uprooted, separated into six fractions [trunk, main branches, lateral branches (including shoots), leaves, fruit, and roots] and analyzed for their total C and N concentrations and dry masses. Soil samples were collected from 0 to 0.6 m in 0.1 m intervals at 0.5 m from the trunk, air-dried, passed through a 2-mm sieve, and analyzed for total C and N concentrations. Undisturbed soil core samples were also taken to determine the bulk density. Dry mass per tree was 5.6 kg for trunk, 12.0 kg f or m ain branches, 15.7 kg for lateral branches, 5.7 kg for leaves, 9.8 kg for fruits, and 10.5 kg for roots. Total amounts of C and N per tree were respectively 2.6 and 0.02 kg for trunk, 5.5 and 0.04 kg for main branches, 7.2 and 0.07 kg for lateral branches, 2.6 and 0.11 kg for leaves, 4.0 and 0.03 kg for fruit, and 4.8 and 0.05 kg for roots. Carbon and N stocks stored in the soil per hectare were 155.7 and 14.0 Mg, respectively, while those contained in pear trees were 17.8 and $0.2Mg{\cdot}ha^{-1}$ based on a tree density of 667 trees/ha. Overall, C and N stocks per hectare stored in the pear orchard were 173.6 and 14.2 Mg, respectively. Compared with results obtained in 2012, the amounts of C stocks have increased by $17.7Mg{\cdot}ha^{-1}$, while those of N stocks remained virtually unchanged ($0.66Mg{\cdot}ha^{-1}$).

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.257-263
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• 2016

Objective of this study was to evaluate the carbon budget on 40 years old pear orchard at Naju. For carbon budget assessment, we measured the soil respiration, net ecosystem productivity of herbs, pear biomass and net ecosystem exchange. In 2015, pear orchard released about $25.6ton\;CO_2\;ha^{-1}$ by soil respiration. And $27.9ton\;CO_2\;ha^{-1}$ was sequestrated by biomass growth. Also about $12.6ton\;CO_2\;ha^{-1}$ was stored at pruning branches and about $5.2ton\;CO_2\;ha^{-1}$ for photosynthesis of herbs. As a result, 25.6 ton of $CO_2$ per ha is annually released to atmosphere. At the same time about 45.7 ton of $CO_2$ was sequestrated from atmosphere. When it sum up the amount of $CO_2$ release and sequestration, approximately $20.1ton\;CO_2\;ha^{-1}$ was sequestrated by pear orchard in 2015, and it showed no significant differences with net ecosystem exchanges ($17.8ton\;CO_2\;ha^{-1}\;yr^{-1}$) by eddy covariance method with the same period. Continuous research using various techniques will help the understanding of $CO_2$ dynamics in agroecosystem and it can be able to present a new methodology for assessment of carbon budget in woody crop field. Futhermore, it is expected that the this study can be used as the basic data to be recognized as a carbon sink.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.87-99
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• 2017

Recently the increase in an abnormal climate events and meteorological disasters which causes a great damage to greenhouse facilities. To minimize and evaluate the expected damages it is necessary to prepare countermeasures and a management system in advance. For this purpose, a quantitative analysis of weather and abnormal climate are needed to investigate protected cultivation areas which are vulnerable to natural disasters. This study focused on protected cultivation areas in Jeolla province, South Korea. Surrogate variables were calculated to analyze the vulnerable areas to meteorological disasters, and spatial distribution analysis was also performed by using GIS to present vulnerable areas on map. The map thus created and was compared with actual data of damages by meteorological disasters which occurred in target areas. The result of the comparison is as follows: About 50% of the target areas showed an agreement between the map created in this study and the actual data, these areas includes Gwangju metropolitan city, Naju city, Yeongam County, Jangseong County, Hampyeong County, and Haenam County. On the other hand, other areas, including Gunsan city, Mokpo city, and Muan County, suffered low damage in spite of high levels of vulnerability to meteorological disasters. This result was considered to be affected by such variables as different structural designs and management systems of greenhouses by region. This study carried out an analysis of meteorological data to find out more detailed vulnerability to protected cultivation area and to create a map of vulnerable protected cultivation areas. In addition, the map was compared with the record of natural disasters to identify actual vulnerable areas. In conclusion, this study can be utilized as basic data for preventing and reducing damages by meteorological disasters in terms of design and management of greenhouses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.325-331
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• 2014

The purpose of this study was to establish the proper sowing time and planting density of cowpeas for labor-saving cultivation. Experiments were carried out in Naju, Jeonnam Province (Latitude $35^{\circ}$ 04' N, Longitude $126^{\circ}$ 54' E) during 2012 and 2013. The intermediate-erect type strains used in this study were Jeonnam1 and Jeonnam2. Sowing was performed five times between June 25 and August 5 at approximately 10-day intervals in order to establish proper sowing time, and sowed at 5,000, 10,000, 15,000, and 20,000 plants per 10a to establish proper planting density. The days from sowing to first flowering was shortest (32 days) in plants sowed on July 25 and became longer for plants sowed on or around July 25. The days from sowing to first flowering was longest (41 days) in plants sowed on June 25. The days from first flowering to first maturing was shortest (8 days) in plants sowed on June 25 and, became considerably longer at later sowing dates. The days from first maturing to first harvesting ranged from 8 to 10 days, with little difference among the sowing periods. Plants sowed on August 5 harvested at the same time, and plants sowed between June 25 and July 25 were harvested either three or two times. The yield was highest in plants sowed on July 25: 209 kg/10a was harvested for Jeonnam1 and 221 kg/10a for Jeonnam2. Furthermore, harvested at the same time enabled when the harvesting was delayed for around 15 days because the share of the seeds first harvested was highest (91%). The proper planting density was estimated to be 15,000 plants/10a, showing the highest yields of 199 kg/10a for Jeonnam1 and 224 kg/10a for Jeonnam2.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.287-287
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• 2009

우리나라의 시설재배면적은 51,237ha에 이르며 수경재배 면적을 제외하면 대부분 경운재배를 하고 있는 실정이다. 경운 작업은 대형 농기구를 이용하여 경운하기 때문에 시설내 토양 입자가 단립으로 잘게 부서지며 대형농기구로 인하여 토양이 답압되고 경운층 아래 경반층이 형성되어 뿌리 발육과 배수 불량의 원인을 제공하게 된다. 경운은 기존에 설치되어 있는 관수시설과 지주, 멀칭을 제거한 후 유기물을 투입하고 2~3회 경운작업 후 다시 소형농기구를 이용하여 이랑을 조성한다. 그리고 제거된 관수시설, 멀칭, 지주를 다시 설치하여야 하기 때문에 시설의 경운재배는 가장 고통스러운 악성노동을 수반하게 된다. 따라서 본 시험에서는 시설 고추 유기재배 시 무경운재배 효과에 대하여 검토하고자 전남 나주시 남평읍 평산리 "JD 중동통 미사질양토"에서 시험을 수행하였다. 2009년 3월 11일 "녹광" 고추 품종을 재식 거리 135${\times}$38cm로 정식하여 7월 27일까지 재배한 후, 시험포를 1/2로 나누어 트렉터를 이용하여 경운작업을 실시하고 2009년 8월 1일 억제작형으로 "녹광" 고추 품종을 정식하였다. 그리고 나머지 시험포 1/2은 전작물을 재배한 이랑에 경운작업을 생략하고 전작물 고추의 식물체는 지제부를 절단하여 분해되도록 고랑을 피복하였으며, 고추 포기와 포기 사이에 무경운으로 고추를 정식하여 시험을 수행하였다. 고추 정식 전 7월 30일에 경운 시험포에 10a당 29톤의 물을 관수하였으며, 무경운 시험포에는 10a당 48톤의 물을 관수하고, 관수 2일 후 시험포의 습도와 이랑에 발생되는 균열수를 조사하였다. 이랑의 수분함량은 표토 0.23%, 토양 30cm 깊이의 수분함량은 0.18%로 경운방법에 따라서 차이가 없었으나 토양 20cm 깊이의 수분함량은 경운은 0.25%, 무경운은 0.14%로 경운재배 토양에 비하여 뿌리의 주요 분포지역인 작토층의 수분함량이 44% 정도 낮았다. 그리고 경운재배 이랑에서는 7~35cm 정도 되는 균열이 m당 22개정도 발생되었으나 무경운에서는 관찰되지 않았다. 시설 토양의 생물다양성 지표가 되는 미소동물의 분포를 조사한(9월 16일) 결과 경운재배 토양에서는 보리톡톡기 등 8종 97개체가, 무경운 토양에서는 10종 101개체가 포획되었다. 경운 방법에 따른 시설 유기재배 고추의 수확과수는 주당 139~141과, 수량은 1,367~1,431g/주가 수확되고 10a당 수량은 경운재배가 2,790kg, 무경운재배는 2,666kg이 생산되어 경운방법에 따른 수량 차는 인정되지 않았다. 경운방법에 따른 경영비를 분석한 결과 무경운은 경운재배에 비하여 10a당 유기질 비료비 178천원, 대농구상각비 211천원, 노력비 261천원의 절감으로 경운재배 경영비 4,815천원/10a 대비 약 14%의 경영비가 절감되었다. 그리고 작기마다 반복되는 경운작업과 관수시설, 멀칭, 지주설치 작업을 1회 설치 작업으로 연속사용이 가능하여 시설재배에서 가장 고통스러운 악성노동의 회피가 가능하였다.

• Journal of Plant Biotechnology
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• v.42 no.1
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• pp.43-48
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• 2015

It is a serious situation that the farmers' income has gradually decreased due to the decline of productivity of fruit trees infected with viroids. It has been known that Persimmon viroid (PVd) and Citrus viroid (CVd) are economically important viroids that can infected persimmon. In this study, the incidence of CVd and PVd in 'Fuyu' persimmon were identified as 41% and 34% in JeollaNam-do, respectively. The collected persimmon samples infected by both PVd and CVd were used for testing efficiency of the viroid inactivation methods. The samples were subjected to single treatment of the heat treatment ($37^{\circ}C$), cold treatment ($4^{\circ}C$), or antiviral agent treatment (Ribavirin), and double treatment of combinations of the three methods. Viroid inactivation efficiency was confirmed through RT-PCR. In the case of the samples subjected to cold treatment for 4 weeks, the viroid inactivation efficiency was most significantly high as 67% against the survival rate of 100%. In addition, in the case of the samples treated for 2 weeks with the antiviral agents and cold treatment, the viroid inactivation rate was similar to that of the cold treatment. In conclusion, the cold treatment showed the highest viroid inactivation efficiency, and this result will provide valuable information for production of viroid-free persimmon.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.57-62
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• 2015

"Nokyang" (Hordeum vulgare L.), a new whole-crop silage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA, Korea in 2012. It was derived from combining "Nagyoung" and breeding line "SB77368-B-145". Among the combinations made in 2001, a promising line, "SB01T2017", showed good characteristics in terms of potential forage yield in the yield trial at Iksan from 2007 to 2009. In 2009, the promising line was designated as "Iksan457" and placed in regional yield trials at six locations around Korea for three years from 2010 to 2012, and was released under the name of "Nokyang." It has the growth habit of a group III creeping plant type, with a light-green leaf and common spike. Its average heading and maturing dates were on May 6 and June 4, respectively, which were later than cultivar "Youngyang." "Nokyang" also showed strong winter hardiness, and a resistance to shattering and barley yellow mosaic virus (BaYMV) similar to those of the check cultivar. The best thing among the traits of one is a new good quality with the plant green at the latter growing period. The average forage dry matter (DM) yields in the regional yield trial were about 12.8 and 11.5 MT $ha^{-1}$ in upland and paddy field, respectively, which were higher than those of the check cultivar, by 7% and 2%, respectively. This cultivar would be suitable for an area of the Korean peninsula where the daily minimum temperature in January is above $-8^{\circ}C$.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.828-832
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• 2013

To report country-specific carbon and nitrogen stocks data in a pear orchard by Tier 3 approach of 2006 IPCC guidelines for national greenhouse gas inventories, an experimental pear orchard field of the Pear Research Station, National Institute of Horticultural & Herbal Science, Rural Development Administration, Naju, Korea ($35^{\circ}01^{\prime}27.70N$, $126^{\circ}44^{\prime}53.50^{\prime\prime}E$, 6 m altitude), where 15-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees were planted at a $5.0m{\times}3.0m$ spacing on a Tatura trellis system, was chosen to assess the total amount of carbon and nitrogen stocks stored in the trees and orchard soil profiles. At the sampling time (August 2012), three trees were uprooted, and separated into six fractions: trunk, main branches, lateral branches (including shoots), leaves, fruits, and roots. Soil samples were collected from 0 to 0.6 m depth at 0.1 m intervals at 0.5 m from the trunk. Dry mass per tree was 4.7 kg for trunk, 13.3 kg for main branches, 13.9 kg for lateral branches, 3.7 kg for leaves, 6.7 kg for fruits, and 14.1 kg for roots. Amounts of C and N per tree were respectively 2.3 and 0.02 kg for trunk, 6.4 and 0.07 kg for main branches, 6.4 and 0.09 kg for lateral branches, 6.5 and 0.07 kg for roots, 1.7 and 0.07 kg for leaves, and 3.2 and 0.03 kg for fruits. Carbon and nitrogen stocks stored between the soil surface and a depth of 60 cm were 138.29 and $13.31Mg{\cdot}ha^{-1}$, respectively, while those contained in pear trees were 17.66 and $0.23Mg{\cdot}ha^{-1}$ based on a tree density of 667 $trees{\cdot}ha^{-1}$. Overall, carbon and nitrogen stocks per hectare stored in a pear orchard were 155.95 and 13.54 Mg, respectively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.175-182
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• 2018

Knowledge of the optimum cultivation period for Chinese cabbage would help growers especially in spring in Korea. Growth and yield of Chinese cabbage in a temperature gradient chamber was evaluated for the growing periods of 64 days from three set of transplanting dates including March 6, March 20, and April 3 in 2017. Air temperature in the chamber was elevated step-by-step, by $2^{\circ}C$ above the ambient temperature. This increment was divided into three phases; i.e. low (ambient+$2^{\circ}C$, A), medium (ambient+$4^{\circ}C$, B), and high temperature (ambient+$6^{\circ}C$, C). The fresh weight of Chinese cabbage was greater under B and C conditions in the first period and A in the second period, which indicated that GDDs affected the fresh weight considerably. However, leaf growth (number, area, length, and width) did not differ by GDDs. Bolting appeared under A condition in the first period, which was caused by low temperature in the early growth stage. Soft rot was developed under C condition in the second period and all temperature conditions in the third period, which resulted from high temperature in the late stage. Fresh weight increased when GDDs ranged from 587 to 729. However, it decreased when GDDs > 729. The maximum expected yield (16.3 MT/10a) was attained for the growing period of 64 days from transplanting date during which GDDs reached 601. The GDDs for optimum cultivation ranged from 478-724 under which the yield was about 95% (15.5 MT/10a) of maximum fresh weight. Such an optimum condition for GDDs was validated at five main cultivation regions including Jindo, Haenam, Naju, Seosan, and Pyeongtaek in Korea. In these regions, GDDs ranged from 619-719. This suggested that the optimum GDDs for Chinese cabbage cultivation would range from 478-724, which would give the useful information to expect the cultivation periods for ensuring maximum yield.