• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.325-326
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• 2005

해양에 적조가 발생하면 해수의 산소결핍 현상을 유발하고 동식물의 성장과 생존에 필수적인 태양광을 차단하여 해양 동물뿐 아니라 식물에게까지 치명적 피해를 준다. 또한, 대형 선박의 안정수(ballast water) 유입시 안정수 내에 포함되어 그들의 생활공간을 이동하면서 선박으로부터 다시 유출될 때 신생활공간에 외래 생물체로 침입하여 그곳의 기존 생태계를 파괴시키거나 교란하는 외래침입생물체는 해양생태계 환경파괴의 주범이다. 따라서 이들 두 종류의 해양생물은 부분적으로 상관성을 지니는 해양수산업계의 천적이며, 해양생태환경 파괴의 원인 제공자로써 마땅히 과학적 방법으로 제거되거나 방지되어야 한다. 이 논문은 해양수산업 계에 막대한 피해를 끼치며 해양생태환경 파괴의 주범으로 등장한 적조생물과 외래침입생물체들이 해수로부터 제조한 플라즈마 반응생성물에 처리된 결과를 분석하여 그 응용성을 조사하였다.

• Korean Journal of Environmental Agriculture
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• v.13 no.1
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• pp.98-110
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• 1994

The fauna of spider species inhabited near paddy fields have been investigated in Chinju and Namhae areas. The spiders collected near the paddy fields in Chinju and Namhae areas were 34 species of 31 genera belonging to 10 families: 34 species on paddy levees; 16 species on barley fields; 17 species on fallow fields; and 18 species on paddy fields. The species diversity was the highest on paddy levee. The dominant species collected from each habitat near the paddy fields were Pardosa astrigera on the paddy levees and barley fields, Pirata subpiraticus on the fallow field, and Pachygnatha clercki on the paddy fields. The spiders inhabited near rice fields can be classified into nine groups based on the ecological and taxonomical characteristics: 1. Pirata spp. 2. Pachygnatha clercki 3. Teridiidae, Erigonidae, Linypidae 4. Tetragnatha spp. 5. Dolomedes surfureus 6. Pardosa spp. 7. Salticidae 8. Thomisidae 9. Clubionidae Among the nine spider groups, the spiders belong to the group 1-5 prefered wet ground or paddy to dry ground, in contrast to the group 6-9 which prefered to live on dry land. The difference of the habitat preference indicated that the former five groups do the important roll as pest predators in paddy, while the latter four group mainly suppress the overwintering pest populations on paddy levees.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.211-217
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• 2001

Field survey for Orius spp., predacious natural enemies of thrips pests, on several plants by beating or sweeping method revealed that O. sauteri, O. strigicollis, O. minutus, and O. nagaii habituated in open fields or in greenhouses of Korea. Among them, O. sauteri was the most dominant species at all areas (83.0~92.5%), followed by O. strigicollis and O. minutus. Especially, O. sauteri exclusively dominated on the economically important crops such as soybean, red pepper, and watermelon. On the other hand, O. strigicallis and O. nagaii occurred mainly on ornamental plants including chrysanthemum and rose and on rice, respectively, during summer-autumn season. The seasonal occurrence varied depending on the plant. Initial population of Orius spp. was first observed on white clover in late May, followed by on soybean, red pepper, an buck wheat in early June, indcating that movement of Orius spp. relates to the flowering time of the plant. Peak of Orius spp. abundance was found first in July and secondly in August or September. On white clover and buck wheat the first peak of abundance was one week earlier than on soybean and red pepper. Therefore, we suppose that wild plants such as white clover can serve as a reservoir for Orius spp. after overwintering.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.229-233
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• 1995

The life history, seasonal occurrence of larval population and natural enemies of Tea leaf roller (Caloptilia theivora (Walshingham) were investigated in field-age. C. theivora had 6 generations a year. The developmental periods from egg to adult emergence were 32.1~38.6 days in spring and fall, and 24.8~32.7 days in summer. The average longevities of adults were 8.4~14.5 days in spring and fall, and 6.3~8.6 days in summer. The average number of eggs laid by a female were 55~71 throughout the season. Larval population density of C. theivora showed 3~4 peaks from middle may in 1992 and 1993. However, population density of 194 was pretty low in early season and exhibited a peak in late September-early October. C. theivora overwintered in pupal stage on the leaves. Four hymenopterous parasitoids of C. theivora larvae were identified ; they are Stenomesius japonicus (Ashmead), Sympiesis ringoniellae Kamijo, Elasmus sp., and S. dolichogaster Ashmead which is dominant.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.482-482
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• 2018

우리나라의 대표 생태계 교란 외래어종인 배스와 블루길은 본래 식용 목적으로 유입되어 하천에서 빠르게 확산되고 있다. 그로 인해 우리나라 토종 어류의 개체수가 감소하고 토종 어류의 서식지가 사라지고 있다. 따라서 본 연구는 배스와 블루길을 대상으로 여러 환경적 요인에 따른 서식처 형성 특징을 관찰하고 분석하여 최종적으로 외래어종의 확산을 차단하는 것을 목적으로 수행하였다. 실험실 연구를 통해 외래어종이 서식처를 형성할 때 주변 환경을 관찰한 결과 특정 반응에 민감하고 장애물과 같은 지형적 요소를 선호하는 행동 특성을 발견하였다. 이에 따라 발견된 특성을 중점으로 하여 지형인자와 조명에 관련된 실험실 연구를 진행하고 분석하였다. 연구를 수행하기 위해 자연 상태에서 채집한 배스와 블루길을 길이 12 m, 깊이 0.6 m, 폭 1 m의 하천과 유사한 자연적 환경이 갖추어진 수조에 이식하였다. 첫 번째로 장애물에 대한 반응 실험은 세 가지 종류의 장애물을 환경 조건이 동일한 수조에 설치하여 어떤 장애물을 더 선호하는지를 관찰하는 방식으로 진행되었다. 그 결과 외래어종은 어류의 위쪽 시야를 차단하는 즉, 상단 벽 장애물을 가장 선호하였으며 이 장애물 밑에 주로 서식처를 형성하였다. 그 이유로는 자연 상태의 외래어종에게는 조류가 가장 큰 천적이므로 조류를 경계하는 습성에 의한 서식처 형성으로 판단된다. 또한 외래어종이 서식처를 형성할 때 크게 고려하는 수온과 장애물 중 어떤 독립변인에 더 민감하게 반응하는지도 관찰되었다. 실험은 춘계에 먼저 수온의 차이를 두어 외래어종이 서식처를 형성하게 만든 후, 서식처로 자리 잡지 않은 곳에 장애물을 설치하여 형성된 서식처를 옮기는지 지켜보았다. 그 결과 앞선 연구로 발견된 외래어종의 서식처 형성에 적당한 수온 $20{\sim}24^{\circ}C$가 아니어도 장애물이 설치된 곳 밑에 서식처를 형성하는 것을 발견하였다. 두 번째로 조명에 관한 실험에서는 외래어종이 수조 전체에 설치된 상단 조명의 아래에는 위치하지 않았으며, 외래어종이 자리 잡은 서식처에 간이 조명을 설치하여 비추거나 하면 피하는 특성을 보였다. 하지만 실험실이 아닌 실제 하천의 환경은 매우 다양한 변수를 포함하고 있어 실험실 수조와의 환경과는 다른 양상을 보일 수 있다. 이와 같은 실제 생태계와 실험실 수조의 환경 차이에서 오는 불확실성에 대한 개선을 위해 실험실에서 진행된 실험 결과를 바탕으로 향후 외래어종의 서식 환경 특성을 고려한 외래어종 확산 차단물을 설계하여 실제 자연 환경에서 외래어종이 어떻게 반응하는지에 관한 연구가 필요할 것으로 판단된다.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.121-133
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• 2017

This study was conducted to investigate the community structure of arthropods, including various insect pests and their natural enemies, in walnut orchards. Furthermore, we tried to compare the species richness and community structure of arthropods by three different sampling methods, including beating, funnel trap, and pitfall trap. Arthropods were surveyed in three walnut orchards located at Gimcheon, Buyeo, and Hwaseong in South Korea from May to September, 2016. A total of 408 arthropod species were identified from 4,372 individuals, and 63 species were collected in all study sites. The species richness was the highest in funnel trap, while the abundance was the highest in pitfall trap. The species composition of the insects collected by the beating method was more similar to that of the funnel trap than the pitfall trap. Although the distributions of the economically important pests were different according to the study sites, six species, including Dichocrocis punctiferalis, Pseudaulacaspis pentagona, Gastrolina depressa, Lycorma delicatula, Metcalfa pruinosa, and Pochazia shantungensis, are the potentially important pests in walnut orchards. We also found a variety of predators and parasitoids, which will be important for walnut pest management.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.88-95
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• 1997

Olfactometer was used to find the attractiveness of kairomone extracted from gypsy moth (Lymantria dispar) to the egg parasitoid (Ooencyrtus kuvanae). The attractiveness of kairomone extracted from scales and hairs which were attached to the surface of the eggs were higher than that of whole eggs with 79.9% and 67.6% respectively. The probing lantency of the egg parasitoid on the extract of scales and hairs were 115.5 sec. and that of whole eggs were 113.2 sec. Eggs taken from egg mass were shown 91.0% of attractiveness to the egg parasitoid, however only 15% of egg parasitoid were attracted by follicles dissected from the host ovary. The probing latency of egg mass was faster than that of follicles dissected from the host with 84.2 sec. and 114.0 sec. respectively. Egg parasitoid showed the most active attractiveness (88.0%), relatively longer examing period (89.2 sec.) and shorter probing latency (26.8 sec.) to the adhesive materials secreted from reproductive accessory glands of the host. Out of six organic solvents used for the extraction of kairomone from the host egg mass, n-hexane fraction received the most active response from xthe egg parasitoid and the parasitoid reared in vivo showed 3 times higher attractiveness to the n-hexane fraction than that of in vitro.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.35-43
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• 2013

All tested Korean populations of the diamondback moth, Plutella xylostella, are known to be resistant especially against pyrethroid insecticides by mutation in its molecular target, para-sodium channel. Moreover, P. xylostella is able to develop resistance against most commercial insecticides. This study was performed to develop an efficient control technique against P. xylostella by a combined treatment of an endoparasitoid wasp, Cotesia plutellae, and a microbial insecticide, Bacillus thuringiensis. To investigate any parasitism preference of C. plutellae against susceptible and resistant P. xylostella, five different populations of P. xylostella were compared in insecticide susceptibilities and parasitism by C. plutellae. These five P. xylostella populations showed a significant variation against three commercial insecticides including pyrethroid, organophosphate, neonicotinoid, and insect growth regulator. However, there were no significant differences among five P. xylostella populations in their parasitic rates by C. plutellae. Moreover, parasitized larvae of P. xylostella showed significantly higher susceptibility to B. thuringiensis. As an immunosuppressive agent, viral ankyrin genes (vankyrins) encoded in C. plutellae were transiently expressed in nonparasitized larvae. Expression of vankyrins significantly enhanced the efficacy of B. thuringiensis against the third instar larvae of P. xylostella. Thus an immunosuppression induced by C. plutellae enhanced the insecticidal efficacy of B. thuringiensis. These results suggest that a combined treatment of C. plutellae and B. thuringiensis may effectively control the insecticide-resistant populations of P. xylostella.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.189-196
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• 2020

Mosquitos serve as vectors for diseases, causing inconvenience as well as a threat to human life and health. Concern about mosquitos introducing and spreading new diseases has been intensifying. We observed a variety of mosquito habitats based on land cover classification from Korea's Ministry of Environment, and the mosquito species that could appear were classified according to the each habitat type. Finally, we suggested the best control methods for each type of habitat considering habitat characteristics and the ecological traits of mosquitos. Urban areas harbor various habitats for pests, contributing significantly to mosquito habitats. Control must be performed regarding larva and adults because various sources for habitats exist. Public mosquito control programs such as educational training, as well as information brochures can be effective in managing mosquito populations and public health. Agricultural areas show high densities of mosquito larva to lentic zones such as reservoirs, wetlands, paddy fields. So, biological control using natural predators may be effective in controlling mosquito populations. Forests are major habitats for Aedes albopctus, so physical controls should be deployed for residents living nearby, and excessive deforestation should be minimized. Other areas including aquatic ecosystems should be adopted regarding biological control using Bti (Bacillus thuringiensis var. israelensis) and chemical control for eradicating mosquitos. We classified habitats into four types of land cover patterns considering ecological traits and habitat preference, and suggest adequate control methods for each habitat type. Our suggestion can be used to positively contribute toward effective managing mosquito's density and reducing the damage to public health.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.47-54
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• 1971

The difference in growth rate of p. orientalis cultured on muddy bottom region and sandy bottom region in a pond filled with sea water were studied. For the investigation of the growth rate, the body length and the body weight were determined. Five individuals from each experimental region were sampled in random. The samples were collected at ten-day intervals. The survival rate, the qredator of p. orientalis, and the water conditions during the experimental period were also determined. The results in this study are summerized as follows: 1. The growth rate of p. orientalis which was cultured in the muddy bottom region was greater than that in the sandy bottom region. This is attributable in either case regardless of whether they were cultured with or without food, 2. The relationship between the culturing period (X) and the body length (Y) is : Muddy bottom, Food Y=0.58497X+25.05210 Sandy bottom, Food Y=0.51030X+26.57900 Muddy bottom, No food Y=0.22352X+32.79360 Sandy bottom, No food Y=0.l1418X+31.20740 3. The relationship between the culturing period (X) and the body weight (Y) is : Muddy bottom, Food Y=0.09062X-2.11140 Sandy bottom, Food Y=0.06992X-1.19640 Muddy bottom, No food Y=0.01615X+0.51150 Sandy bottom, No food Y=0.00495X+0.56150 4. When the predator is not present, $84\%$ of P. orientalis may survive. 5. Acanthogobius flavimanus is one of the predator of P. orientalis. 6. It is considered that the variation of water conditions of the pond, in which water had been exchanged 12 times per month, did not affect to the survival rate of P. orientalis.