• Korean journal of applied entomology
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• v.51 no.4
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• pp.411-419
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• 2012

The lure-distance of Riptortus pedestris aggregation pheromone was elucidated and the damage mitigation effect by mass trapping of R. pedestris was examined in commercial soybean fields. The recaptured ratio showed that 76.1% of total recaptured individuals were lured within 40 m and 89.0% of total recaptured adults were arrested in the lower 80 m. There is not much difference in the number of recaptured individuals according to the location of installed traps in the experiment. There was linear correlation between the total installed number of traps and the total number of trapped individuals in commercial soybean fields. and the highest yield (261.8 g/10 stems) was investigated in the field that had installed a pheromone trap per $770m^2$. No relationship wasf found between the covered areas of a pheromone trap for mass trapping and yield loss. The ratio of type A seed (healthy) was higher in the field that installed a trap per $385m^2$ and $770m^2$ (around 62%) and type B seed (showing distinct injury marks) was lower in the same fields (around 27%). From this result, we could reduce slightly the damage of soybean seeds by the mass trapping of Riptortus pedestris adults with an aggregation pheromone trap per $385{\sim}770m^2$ area range.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.245-251
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• 2009

Without pesticide applications, mass-trapping by sex pheromone was successful to control Spodoptera litura (Fabricius) in a large scale tomato glasshouse (10,000 $m^2$) at a low cost of 60 won/$m^2$. Pheromone traps were placed both inside and outside of the glasshouse. Inside the glasshouse traps were installed in a regular space, one trap per 500 $m^2$, to catch the moths that were present in the glasshouse, and traps were also set outside of the glasshouse, at intervals of ca. 20 m, to prevent the moths from invading the glasshouse. In the experiment, more than 400 S. litura were captured per trap.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.475-482
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• 2019

Over 3,200 large baleen whales including 3,173 fin whales, 7 blue whales and 28 humpback whales were hunted by Japanese whaling companies in the Yellow Sea during Japanese colonial period (1916~1944). As a result, these large baleen whales are under the endangered state in the Yellow Sea. The Yellow Sea had good living conditions for large baleen whales in the water temperature ($4{\sim}26^{\circ}C$) and food supply. The whaling on the large baleen whales was carried out mainly from early winter to late spring. The possibility of large scale whaling was caused by the migration of these baleen whales from other areas for the feeding on abundances of Euphausia pacifica in the surface layer during these seasons. During summer and autumn season, the baleen whales moved to other areas (good feeding ground as Woolsan offshore waters), because Euphausia pacifica stayed below the strong themocline which was formed from June to October in the Yellow Sea.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.63-75
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• 2022

Semiochemicals including pheromone are chemicals used in chemical communication of insect. Semiochemicals have been widely used for population monitoring, mass trapping, and mating disruption of insect pest. In this review article, the current status of pheromone research of major forest insect pest in Korea such as Monochamus alternauts, M. saltuarius, Matsucoccus thunbergianae, Platypus koryoensis, Glyphodes perspectalis, Dioryctria abietella, Lymantria dispar, Synanthedon bicingulata, and Naxa seriaria was introduced, and the results were compared with those reported in other countries. Based on the analysis of current pheromone research of forest insect pests, future studies and development direction was suggested.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.365-366
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• 2003

주꾸미는 서해 연안 어족의 자원감소와 함께 어장 환경 악화에 의해 매년 생산량이 감소되고 있으며, 금후에는 양적 성장이 어려울 뿐만 아니라 어업인의 소득 감소가 예상되고 있다. 따라서 주꾸미의 생산량을 지속적이고 안정적으로 유지하기 위해서는 지금까지의 어선ㆍ어업에서 탈피하여 주꾸미의 인공 종묘생산 및 자원조성을 위한 종묘의 대량 방류가 필요하다. 주꾸미 종묘생산시 시료의 무게 측정, 표지작업, 인공채란, 수송 그리고 질병치료 등을 위해 주꾸미 유생을 그물망으로 포획하는 것은 유생에 물리적 손상과 스트레스를 주어 폐사의 1차 원인이 되기도 한다. (중략)

• Korean journal of applied entomology
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• v.61 no.1
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• pp.51-62
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• 2022

Numerous insect pests threaten the Korean orchard industry through feeding on various tissues of fruit trees. Generally, the control of economically important orchard pests is based on the use of chemical insecticides. Owing to growing concerns regarding the environmental and human health effects of insecticides, environment-friendly pest control strategies are urgently needed. Pheromones of orchard pests could lead to an environmentally safe control system based on mating disruption or mass trapping. This review summarizes the functions and compounds of known pheromones from 51 orchard pests in Korea. The pheromones identified to date from 14 species in the families Miridae, Aphididae, Diaspididae, Pseudococcidae, Rutelidae, Cecidomyiidae, and Eurytomidae and 26 species in the order Lepidoptera are female-produced sex pheromones that attract only males. In contrast, all known examples for 11 species in the families Alydidae, Pentatomidae, Thripidae and Cerambycidae are male-produced aggregation pheromones that attract both sexes. Research on pheromones in new pests, kairomones in key orchard pests, mating disruption dispensers to generate prolonged release of the pheromones, and trap design and trap location for mass trapping will be required for the expanded use of pheromones and other semiochemicals in orchard pest management in the future.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.245-253
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• 2023

A control technique using mass-trapping was developed against thrips infesting hot peppers cultivating in greenhouses. It was essential to develop effective lure(s) attracting thrips for the control technique. Especially, mass-trapping using aggregation pheromone (AP) of the thrips was not much effective in open field cultivating hot peppers. This study aimed to develop a new lure to enhance the attractiveness of AP-based mass-trapping. In addition, this study was designed to investigate the decrease of attractiveness of the AP-based mass-trapping in the open field conditions. Methyl isonicotinate (MIN) as a new lure was assessed by the laboratory olfactometry and showed its attractiveness to thrips and its mixture effect with AP to attract the thrips. These results led us to test the AP+MIN mixture in the open field conditions cultivating hot peppers. The mixture significantly enhanced the mass-trapping efficacy in the open field conditions. Especially, the significant increase of the captured numbers was found in the western flower thrips, Frankliniella occidentalis. Furthermore, the increase of the AP concentration in the mass-trapping significantly increased the captured numbers in F. occidentalis and other thrips occurring in the hot pepper field. This study demonstrated the difference in the AP-based mass-trapping efficacy of the thrips between greenhouse and open field conditions. It also showed the increase of mass-trapping efficacy by increasing AP concentration in the trap. Especially, this study proposes a high efficient mass-trapping technology by the addition of MIN to AP especially against F. occidentalis.

• Research in Plant Disease
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• v.24 no.3
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• pp.202-212
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• 2018

Major viruses infecting rice are transmitted by planthoppers such as small brown planthopper (SBPH), brown planthopper (BPH) and white-backed planthopper (WBPH). In this study, we investigated planthoppers captured during 2015 to 2017 by a smart sky net trap (SSNT) system installed in 40 areas in Korea, which is an automatic, rapid and real-time insect surveillance system. The average rates of captured migration plnathoppers was 27.5%, 17.2%, 15.3% and 10.9% in Chungcheongnamdo, Jeollanamdo, Jeollabukdo and Gyeonggido, orderly. The highly migrated month was July for SBPH, July to August for WBPH and August for BPH. To investigate the viruliferous rates of planthoppers of rice during 2015 to 2017, we performed RT-PCR using specific primers for each rice virus. RBSDV was detected from 0.4% in SBPH, while no viruses were detected in BPH and SBPH. Rice planthoppers exist all around in Asia. They can move long distance by wind from southern countries to Korea. Monitoring the migration of rice planthoppers and their viruliferous rates is important to prevent the outbreaks of rice virus diseases.

• Research in Plant Disease
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• v.18 no.3
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• pp.245-249
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• 2012

The small brown planthopper (Laodelphax striatellus) is one of the most important rice pests in Republic of Korea because it damages rice plants not only by sap-sucking but also by transmitting Rice stripe virus (RSV). Outbreaks of RSV are closely related to outbreaks of the small brown planthopper (SBPH). Therefore, it is very important to control SBPH for the management of RSV. Mass-migrating SBPH collected by aerial net traps in June 2011 at Taeanup, Geunheungmyon and Gonammyon in Taeangun were examined for virus carrier status and effects of the pesticide, 'Myungtaja', on the control of RSV. Among 1,217 SBPH trapped, about 7.7% were detected as RSV positive and 4.4% were positive for Rice black streak dwarf virus (RBSDV) by RT-PCR. After the mass migration, pesticide 'Myungtaja' was sprayed once or twice on rice fields and compared to untreated fields. The incidence of RSV was not affected by the frequency of spraying 'Myungtaja' but was influenced by the time of pesticide treatment. Myungtaja' treatment within 5-7 days after mass migration resulted in the most efficient RSV control, resulting in RSV incidence decreased by 87.6% compared to the control. Therefore, we conclude that pesticide spraying for RSV control was most effective when it was done within 5-7 days after mass migration.

• Electrical & Electronic Materials
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• v.9 no.2
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• pp.204-207
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• 1996

태양의 광에너지를 전기에너지로 변환하는 태양전지의 재료는 현재 무기반도체가 주를 이루고 있지만 최근 유기반도체가 재료자체 물성의 연구진전과 더불어 태양전지로서 개발가능성이 논하여 지고 있다. 한편 유기반도체의 장점은 1)박막으로 제작이 용이하고 2)대량생산에 의한 저가제조가 가능하며 3)경량화를 할 수 있고 4)그 기능의 다양성을 줄 수 있다는 것이다. 또한 단점은 캐리어 트랩 밀도가 커서 반송자(carrier)의 수명과 이동도가 작고 확산길이도 짧기 때문에 광수집 효율이 매우 낮아 광전변환효율이 낮다는 것이다. 또한 일반적으로 유기반도체는 저항율이 커서 오옴성 접촉이 어렵고 입사광 강도의 증대에 따라 변환효율이 감소하는것도 큰 문제로 되어있다. 따라서 본고에서는 지금까지 유기반도체를 사용한 태양전지의 원리 및 제조기술을 간단히 살펴보고 특성과 연구동향등을 분석하여 앞으로 유기반도체 태양전지의 나아가야할 방향을 찾아보고자 한다.