• Korean journal of applied entomology
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• v.40 no.3
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• pp.227-233
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• 2001

Four polymorphic allozymes were used for genetic analysis of overwintering populations of field diamondback moth, Plutella xylostella (Linne). Different allele frequencies were found among three local populations of Andong, Youngchon, and Yangsan in all loci. Two allozyme loci (acid phosphatase and phosphoglucomutase) showed significant deviation from Hardy-Weinberg equilibrium in allele frequencies among these populations. Estimated Nei's genetic distance varied from 0.0151 between Yangsan and Youngchon to 0.0877 between Andong and Youngchon. Compared with the previous genetic distances in this moth, a little higher genetic differentiation among these overwintering populations suggests that there would be a specific genetic bottleneck in each local population during overwintering period.

• Landscaping Tree
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• s.147
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• pp.38-42
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• 2015

최근 기후변화 개방화로 산림과 농경지 모두가 서식처인 외래종 꽃매미, 미국선녀벌레, 갈색날개매미충 등의 새로운 해충이 돌발적으로 발생하여 그 피해가 심각해지고 있다. 이 해충들은 흡즙성의 가해양상을 보이며 알로 월동하고 생활사가 유사하며 기주범위가 상당히 넓다는 공통적인 특징을 지니고 있다. 꽃매미의 유입 정착사례에서 보듯이 최근의 기후변화가 발생과 관련되어 있어 앞으로 수목과 농작물 모두에 피해가 우려되고 있는 실정이다. 특히 최근 온화한 겨울 기온과 봄철 이상기온으로 인해 알로 월동하는 해충들의 월동치사율이 감소하고 발생시기가 빨라질 것으로 예측되는 상황에서 이들 문제 해충의 생태 및 방제법에 대하여 간단히 소개하고자 한다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.7 no.1
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• pp.23-29
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• 1986

가정원예라 하면 분재(盆栽), 관엽식물, 난, 분화(盆花), 테라리움(Terrarium), 수경원예(水耕園藝), 정원 수 가꾸기 등을 들 수 있는데 그 중에서 분재와 실내식물(관엽식물 및 겨울철 분화)에 대한 월동관리요령과 농약사용법을 알아보기로 한다.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.127-135
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• 1998

To study overwintering biology of the oriental tobacco budworm (OTB), Helicoverpaa.ssulta, OTB larvae were collected from middle and southern region of Korea in the autumn and rearedto diapausing pupae. Diapausing pupae were held at two different locations (Suwon and Chinju) and wererecollected in the spring to observe adult emergence rate and duration to adult emergence at 25$^{\circ}$C. Thesurvivorship of overwintering pupae was less than 5% when the pupae were buried in the soil in 20cmdepth. However, more than 60% of the pupae survived when they were kept in the plastic cup withartificial diet and were buried in the soil. The mean developmental periods of overwintering pupae at 25"C varied from 20.4 days to 43.9 days depending on years and locations where larvae were collected andpupae were held. The proportion of individuals which required longer than 30 days for development washigher in the population from the middle regions than those of southern regions. However, the proportiondecreased when the pupae collected from middle regions were held at Chinju, southern region. Chinju, southern region.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.218-225
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• 1992

This experiment was carried out to compare the varietal differences of winter hardiness based on the values of winter hardiness index(W1) and the dry weight of plant per relative tiller appearance rate (DWIRTAR), and the evaluate the method of measurements for winter hardiness in 17 orchardgrass varieties grown under mountainous area of Tackwalyon, Kangwon-do. Korea. The results were summarized as follows: 1. Seedling vigours(SV) of plant before wintering indicated highly significant negative correlation with the dry weight of 1st cutting(DW) and the dry weight of plant per relative tiller appearance rates (DWIRTAR). 2. The dry weight of 1st cutting(DW) indicated significant positive correlations with the number of tillers per plant(NT). dry weight of a tiller(WT), lield survival rate(SR). heading rate(HR) and the dry weight of heading tillers(HDW). 3. Correlation coefficients of the dry weight of 1st cutting(DW) with winter hardiness index(W1) was 0.499(p<0.05), and the dry weight of plant per relative tiller appearance rates(DW/RTAR) was 0.895(p<0.001), respectively. 4. Between the winter hardiness index(W1) and field survival rate(SR) showed highly significant positive correlation(p<0.001). And, the dry weight of plant per relative tiller appearance rates(DW/RTAR) showed highly significant positive correlation(p<0.001) with the dry weight of a tiller(WT) and the dry weight of heading tillers(HDW). 5. The varieties were classified into 2 groups by winter hardiness index(W1). The 13 varieties of Hallmark. lna, Rancho, Amba, Filippa, Sparta, Hokuto, Kitamidori, Okamidori, Wasemidori, Shinyo, Potomac and Summer-green belong to the group of W1)100, and 4 varieties of Able, Juno, Napier and Jesper belong to the group of WI(100, respectively. 6. And, also classified into 2 groups by the dry weight of plant per relative tiller appearance rates (DWIRTAR). The 4 varieties of Amba, Okamidori, Wasemidori and Summer-green belong to the group of DW1RTAR)l.O and 13 varieties of Able, Hallmark, Ina, Juno, Napier, Rancho, Filippa. Jesper, Sparta, Hokuto, Kitamidori, Shinyo and Potomac belong to the group of DW/RTAR(1.0, respectively. The variety with DW/RTAR)I.O is belong to the group of high potential winter hardiness, and also obtained a high values over the 100 of winter hardiness index(W1). 7. The dry weight of plant per relative tiller appearance rates(DW/RTAR) may be a very useful ecological character to evaluate the potential winter hardiness of orchardgrass varieties grown under mountainous area of Taekwalyon(altitudinal ranges about 800m).

• 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.

• Korean Journal of Environment and Ecology
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• v.34 no.3
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• pp.191-197
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• 2020

The purpose of this was to examine the differences of large whopper swan (Cygnus cygnus) in wintering habitat preference among bridge sections of the lower Nakdong River of the Nakdong River Estuary, the largest whopper swan's wintering habitat in Korea. This species is designated and protected as Natural Monument in Korea. The survey was conducted in six time-series during the 2018~2019 wintering season, and it found up to 500 whopper swans were wintering in the lower Nakdong River. For the survey, a seven sections were set up based on the bridges across the river. Whopper swans were rarely observed in five narrow sections where the distance between bridges was less than 2 km. The stable population of the whopper swan was observed only in two broader sections where the distance between bridges was is over 4 km. As these sections were relatively little affected by artificial interference, the distance from the mouth of the Nakdong River was not a factor. Securing a stable space is considered as one of the most important factors for wintering of whopper swans, which are an endangered species. The survey results indicate that the distance between bridges should be at least 4 km to secure the whopper swan's stable habitat. These results are expected to be a reference to the development or restoration of the river ecosystems, especially bridge construction.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.355-365
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• 2014

It has been unclear whether the diamondback moth, Plutella xylostella can overwinter in Korean field conditions. This study determined overwintering conditions of P. xylostella by conducting field exposure tests based on its cold tolerance and monitoring overwintering populations by direct examination of overwintering larval habitats and capturing adults with sex pheromone traps. In addition, the overwintering populations were analyzed using polymorphic genetic markers to trace their sources. When all immature stages of P. xylostella were exposed to $-5^{\circ}C$, which was the temperature much above their supercooling points, they significantly suffered with direct cold injuries, where larval stage was most tolerant to the cold injury. However, the exposure to $5^{\circ}C$ for a long period (4 weeks) did not give any significant cold injury to nonfeeding stages, while this treatment gave lethality to larval stage without diet. When all developmental stages of P. xylostella were exposed to open field conditions during winter, they exhibited significant decreases of survival rates. However, some protected and indoor conditions reduced the cold injuries and the diet provision significantly increased larval survival rates. Adult monitoring with sex pheromone during winter period indicated that the first captures were observed at similar periods at different locations (${\approx}260$ Km apart). The overwintering adults were captured until early April. Genetic variation of these overwintering populations was analyzed with polymorphic molecular markers, indicating significant genetic divergences among the overwintering populations. This study indicates that P. xylostella can overwinter in southern Korean fields or some protected greenhouses with host plants.

• The Safety technology
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• no.34
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• pp.50-51
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• 2000

기온이 내려가는 겨울철에는 모든 것이 수축되어 딱딱하게 되고, 작은 충격에도 쉽게 고장이 난다. 사람의 경우도 여름에 넘어졌을 때보다 겨울에 넘어져 골절 등으로 다치는 경우가 많다. 겨울철에 안전운전은 필수이며, 급변하는 날씨에 대비한 자동차 점검 및 월동준비는 철저히 해야 할 것이다.

• 농업기술회보
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• v.51 no.5
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• pp.21-22
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• 2014

호밀은 월동작물 중에서 추위에 가장 강하고, 낮은 온도에서 빨리 성장하는 특성을 가지고 있어 다른 작물보다 한 달 빠른 4월 중 하순에 수확이 가능하다. 이런 장점으로 호밀을 월동기온이 낮아 겨울작물 재배가 어렵거나 벼를 빨리 이앙하는 지역에서 풋베기용이나 사일리지용 조사료로 많이 재배되고 있다. 그러나 호밀은 도복에 약하고, 이삭이 나온 이후 사료의 질이 떨어지기 때문에 수량이 많고 사료가치가 좋은 호밀 조사료를 생산하려면 세심한 관리가 필요하다.