• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.60-65
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• 2008

For autumn field cutting of Sedum sarmentosum, the effects of cutting site (distal, middle, and proximal) and planting method (space drill seeding, drill seeding, and broadcast seeding) on survival rate and growth characteristics were investigated at pre- and post-winter season. Plant height root length, stem number per plant, number of branch per plant, fresh weight of shoot, and dry weight of shoot were significantly superior in distal site at pre-wintering (40 days after cutting). At post-wintering (May 10th), stem number per plant, fresh weight and dry weight per $m^2$ in cutting of distal site showed a significant increasement compared to the cutting of proximal site. At pre-wintering (40 days after cutting), the growth in space drill seeding was well than that in drill seeding and broadcast seeding, and fresh weight and dry weight per $m^2$ in space drill seeding were high in order of space drill seeding, broadcast seeding, and drill seeding. At post-wintering (May 10th), stem number per plant, fresh weight and dry weight per $m^2$ in space drill seeding were significantly increased than those in drill seeding. Accordingly, the cutting using distal site of stem in autumn field cutting was desirable for the growth and shoot yield. The space drill seeding showed the highest yield potential among three seeding methods, but broadcast seeding was favorable in saving of labor, because the fresh weight of shoot in broadcast seeding was similar in the space drill seeding at post-wintering.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.70-73
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• 1992

사료작물 저온발아성(低溫發芽性)은 수수 $\times$ 수단그라스잡종들이 좋았고 옥수수와 수단그라스는 비교적 저조하였고 PGE에 종자침지처리가 이탈리안라이그라스의 저온발아에 효과적이었다. 간척지의 수수파종시 염해 방지에는 모래를 파종후 피복하여 제염(除鹽) 효과를 얻을수 있었다. 수수류의 토양수분조건에 대한 광합성 연구는 포장용수량의 $60\sim80%$의 조건에서 광합성이 가장 왕성하였고 건물수량도 동일한 결과를 나타내었다. 옥수수의 광이용과 초형과의 관계연구는 이삭상부 엽각의 직립화는 밀식 조건에서 광이용성이 증가되었고 건물 및 종실수량에서 종수가 있었다. 또 밀식화에 따라 직립화 경향이 현저하였으며 옥수수의 다수성초형의 육성이 요청되었다. 질소시비에 대한 청예류의 생장 반응 연구들은 수단그라스에서 10a당 40Kg까지는 건물수량생산을 증가시켰으나 80Kg/10a 사용시는 질산태질소함량이 중독위험치를 초과하였다. 이러한 질산태질소의 중독위험은 6엽기까지 존재하였고 청산중독의 위험농도는 4엽기 이전까지, 또 18/$8^{\circ}C$의 저온조건에서 나타났다. 옥수수의 적정재식 밀도는 10a당 16.600본까지 밀식할수록 증가되었으나 가소화수량과 종실수량은 5.500본과 10Kg/10a 에서 최고치를 나타내었고 질소 추비 효과는 대관령 같은 고산지대에서는 나타나지 않았다. 맥류의 총체(總體)사료 이용성은 호밀, 밀, 보리 순(順)으로 저하하였고 파종시기가 빠를수록 월동성이 향상되었으며 수확적기는 출수후 24일경이었다. 호밀의 청예이용에는 월동후 2회예취와 12cm높이가 건물수량과 TDN수량을 높힐 수 있었다. 수수$\times$ 수단잡종의 출수기 이전 예취는 고사 경비율을 줄일 수 있었고 년 2회 예취와 예취높이 10cm가 가장 좋았다. 유채는 생육기간이 길어질수록 수량은 증가하였고 소화율의 감소도 현저하지 않았다.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.354-361
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• 2012

This study was conducted to evaluate on the freezing tolerance of introduced blueberry cultivars in Korea and to investigate availability of portable timber moisture meter for simple and rapid diagnosis of blueberry-shoot damage by freezing during wintering. Frost tolerance of blueberry cultivars showed big difference that rates of blueberry-shoot death were widely distributed from about 0% to 100% after wintering. Optical density in TTC reduction of blueberry twig treated low temperature was low in order of $-40^{\circ}C$ < $-21^{\circ}C$ < $4^{\circ}C$. Hardiness evaluation of visible injury in the cross-sectional surface color did not agree with that of rates of blueberry-shoot death during wintering. Lowest water content of blueberry stem measured by timber moisture tester during wintering was about 15%. During wintering, water contents of blueberry stems were higher at lower part of tree, but were low at end part of stems, and then when the blueberry grew again for spring, the water content gradually increased to 20~40%. Water content of blueberry stem with freezing injury during wintering decreased to under 5% by desiccation. Therefore it is assummed that the moisture content of blueberry stem injured by freezing during wintering was about under 14%, and it is expected that portable timber moisture meter could be available for rapid diagnosis of blueberry freezing injury in field.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.201-208
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• 2008

Spring phonology of the oriental fruit moth, Grapholita molesta, was monitored using sex pheromone traps in apple cultivating areas. Their occurrence was earlier in southern areas and their population sizes were significantly different among orchards even in a local cultivating zone. The overwintering populations appeared to move between local orchards, based on the fact that monitoring data obtained at the sites between orchards were similar to those of nearby orchards. However, within orchards, these adult movements appeared to decrease and showed skewed occurrences at the side of upwind direction or close to neighboring orchards. At initial occurrence peak(April 20-25), the ovenvintering populations of the different localities were collected and analyzed in their genetic distances. PCR-RAPD analysis indicated that there were significant genetic differences among the overwintering populations of G. molesta. This genetic differentiation of overwinterin populations may be due to genetic bottleneck following differential selection pressures against the subpopulations of G. molesta during winter on the basis of the RAPD analysis that each early spring population was significantly different to its previous fall population in the same locality.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.191-191
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• 2020

• Korean journal of applied entomology
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• v.42 no.2
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• pp.111-118
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• 2003

The population density of the Cotton caterpillar, Palpita indica (Saunder) larvae was gradually increased until 10th October and then decreased rapidly after that time at the watermelon culture of rain sheltered house. After 15th October, many larvae went to soil and molted to pupae for the hibernation. Most of pupae were found in pF 2.4 soil moisture condition, but none in pF 1.5 hydro-morphic soil. Most of the pupae were found below 5cm and there was no pupa below 10cm from the soil surface. The sex ratio of the overwintering pupae was 1.09 : 1.00. For the monitoring of the cotton caterpillar adults using sex pheromone compounds, different mixture ratios of each pheromone compound were investigated with (E)-11-hexadecenal and (E, E)-10,12-hexadecadienal. Seven versus three ratio of (I)-11-hexadecenal and (E, E) -10,12-hexadecadienal was more attractive than any other ratio, and then followed by 6 : 4, 8 : 2, 9 : 1, and 5 : 5 mixtures. As a result of monitoring with 7 : 3 mixture of (E)-11-hexadecenal and (E, E)-10,12-hexadecadienal, occurrence peaks of cotton caterpillar adults showed 4 times per year. The first time of adult appearance was late July in 2000 and middle July in 2001 and the highest number was collected on late September.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.14-18
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• 2004

This study was aimed at searching for the wintering Cd hyperaccumulators as the life cycle of existing hyperaccumulators were mostly from spring to early winter season. The wintering hyperaccumulators can be effective for saving time loss during the winter. A pot experiment was conducted to search for hyperaccumulators through out the native wintering plants. Seven species of native wintering plants were applied; Bromus catharticus, Oxatis corniculata, Festuca rubra, Thlaspi. arvense, Agastache rrgosa, Viola seoulensis, and Patrinia rapestris. Among them, Bromus catharticus and Thlaspi arvense were selected as Cd hyperaccumulators; the two plants accumulated 112.35 and $86.69mg\;kg^{-1}$ of Cd in the shoot, respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 1977.05a
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• pp.26-27
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• 1977

• Agrochemical news magazine
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• v.23 no.2 s.175
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• pp.18-21
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• 2002

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.642-649
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• 2014

Mallard (Anas platyrhynchos) is the abundant winter visitor in South Korea. Mallard migrates long distances between Russian Siberia and Korea. This species prefers a rice paddy area as their winter habitat. We captured birds using cannon-net, and attached the GPS-Mobile phone based Telemetry(WT-200) on Seven Mallards in the winter of 2011~2013. We were monitored wintering home-range and movement distance. We analyzed the tracking location data using ArcGIS 9.0 and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range in the wintering ground by MCP was $118.8km^2$(SD=70.1, n=7)and the maximum home-rang was $221.8km^2$ and the minimum was $27.7km^2$. Extents of home-range by KDE were $60.0km^2$(KDE 90%), $23.0km^2$(KDE 70%) and $11.6km^2$(KDE 50%). Mallard moved an average of 19.4 km from start site(attach to WT-200 site), maximum moved was 33.2 km and minimum moved was 9.4 km. The average distance of 0.8 km between GPS fixed point(range 0.2~1.6 km), maximum moved was 19.7 km. Mallard moved a very short distance in wintering season and showed a very high water-dependent trends in wintering site.