• Journal of Ecology and Environment
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• 제35권1호
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• pp.9-14
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• 2012

Yellow bitterns (Ixobrychus sinensis) are a small wetland bird common to Asian countries including South Korea, Japan, and China. The aim of this study is to describe diet of yellow bitterns during the breeding season in artificial wetland of northeastern South Korea between May to August 1999-2001. For the purposes of this paper, we observe the frequency of nest visiting by parents during the chick rearing period. A total of 98 boluses regurgitated by 52 chicks aged 1 day to 11 days after hatching form the sample and are shown to contain 323 food items. A bolus contained mean 3.8 items and weighs 0.2 g to 7.7 g. The most regularly occurring food items recorded are fish (63%) and insets (33%). In terms of fish, top mouth minnows (Pseudorasbora parva) and crucian carps (Carassius auratus) are frequently observed. In terms of insects, there are mosquitoes (Diptera), instars of dragonfly (Libelluidae), damselflies (Coenagrinonidae) and water bugs (Diplonychus japonicus). Yellow bitterns were also shown to feed on bull frogs (Rana catesbeiana), shrimp (Palaemonidae), and spiders (Araneae). The size of fish in a bolus ranged from 15.56 mm to 93.73 mm (mean, 37.08 mm). The amount of food can be observed to increase with the age of chicks (r = 0.279, P = 0.025, N = 64) but parents did not provide larger fish as chicks grew. Parent birds visited nests more frequently when they have a larger brood ($F_{1,21}$ = 14.529, P = 0.001). Our results suggest that fish is the most important prey during the breeding season and that age of chicks is related to amount of diet in yellow bitterns.

• 농업과학연구
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• 제45권1호
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• pp.28-37
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• 2018

This study was done to develop environmental risk assessments and a biosafety guide for insect-resistant genetically modified rice at a LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-9) resistant to Cnaphalocrocis medinalis and on non-GM rices (Dongjin and Ilmi) were investigated. The Bt-9 event was therefore evaluated under field conditions to detect possible impacts on the above ground insects and spiders. The study compared transgenic rice and two non-GM reference rices, Ilmi and Dongjin, at Gunwi in Southern Korea in 2016. Each rice was grown on three $18m^2$ plots with a randomized block design. A total of 4,243 individuals from 43 families and 9 orders were collected from the LMO isolation field. In the three types of rice fields, a total of 1,467 individuals from the insect-resistant genetically modified rice (Bt-9), 1,423 individuals from the Ilmi, and 1,353 individuals from the Dongjin were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies and other insects on the insect-resistant genetically modified rice (Bt-9) and non-GM rices. These results provide the diversity and population density of non-target insects for an environment risk assessment survey on insect-resistant genetically modified rice and could be used as a guideline to make a biosafety assessment method for genetically modified crops.

• Journal of Ecology and Environment
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• 제32권1호
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• pp.33-39
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• 2009

Brood caring behavior was observed in Amaurobius ferox (Araneae, Amaurobiidae), a semelparous subsocial spider, from cocoon construction until the emergence of spiderlings from the cocoon. Unlike most spiders, which emerge from cocoon by their own means, A. ferox mothers intervene in the process of the emergence of their young. I manipulated broods by removing the mother prior to emergence to determine the effects of maternal behavior on the emergence of spiderlings. My results showed that maternal intervention making the cocoon expansion and its exit, is not absolutely necessary for the emergence of A. ferox spiderlings from the cocoon. Nine clutches out of ten were able to get out of the cocoon by their own means without their mother's help. There was no difference between control groups ('with mother') and experimental groups ('without mother') in the number of spiderlings that emerged ($96.9{\pm}25.3$ vs. $90.4{\pm}14.2$, respectfully) and in the time from the beginning to the end of emergence ($36{\pm}12$ vs. $41{\pm}17$ hours). Time from eclosion until the emergence of the first individual in a clutch, however, was greater in the mother-absent group (3.5 days) than in the control group (2.0 days). The construction of the cocoon by the mother required always occurred in the same area within the retreat, and took approximately 6 hours, and the mother guarded the eggs during the incubation period. The emergence of the spiderlings followed a sigmoidal pattern. After emergence, the spiderlings formed a very compact group on the cocoon, which may be important in securing maternal care. The absence of cribellum and calamistrum, structures likely involved in their survival, observed in individuals of the first instar suggests that in the first stage of life, the spiderlings are dependent on their mother.

• 한국응용곤충학회지
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• 제33권4호
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• pp.270-280
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• 1994

우리나라의 본농초기 해충군과 비래성 멸구류를 통합관리할 수 있는 살충제의 체계적 처리법을 확립하기 위하여 이앙직접 carbofuran 토양혼화처리후에 벼멸구 비래시기와 buprofezin 처리시기 및 처리약량을 달리하였을때의 벼멸구 밀도 억제효과를 조사하였다. 이앙직전 carbofuran (3G) 토양혼화처리의 효과로부터 벗어난 7월중 비래 벼멸구에 대한 buprofezin (25% WP)의 적정처리시기는 7월말~8월초이었다. 이때 buprofezin 의처리약량은 관행처리량보다 훨씬 낮은 수준인 7.0 g a.i./10a으로도 벼멸구의 증식밀도를 효과적으로억제할 수 있었다. 이와 같은 carbofuran 토양혼화처리와 buprofezin 처리는 흰등멸구에 대해서도 탁월한 방제효과를 나타내었으며 멸구류를 천적인 거미밀도에 대해서는 영향을 미치지않았다. 따라서 우리나라의 수도해충 발생특성을 고려할 때 carbofuran 과 buprofezin을 이용한 살충제 체계적 처리 즉, 이앙직전 carbofuran 토양혼화처리후 7월말-8월초 bupro-fezin처리는 본 논초기 발생해충들 및 비래성 멸구류를 효과적으로 방제할 수 있는 방제체계로 생각된다.

• 한국응용곤충학회지
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• 제33권4호
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• pp.281-285
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• 1994

키틴합성저해제인 diflubenzuron, triflumuron, chlorfluazuron을 갈색거처리와 유충과 번데기에 처리하여 효력검정법을 개발하였다. 유충에 대한 처리는 국소처리와 독먹이처리를 행하였고, 번데기에 대하요 용체침적처리와 미량주사처리를 행하였다. 유충에 대한 10$\mu\textrm{g}$ 국소처리와 번데기에 대한 100ppm 용체 침적처리 결과 세약제 모두 유충 및 번덱의 발육에 아무런 영향을 주지 않았다. 유충에 대한 독먹이 처리에 있어서의 {{{{ { LC}_{ 50} }}}}값은 diflubenzuron 11.3, triflumuron 42.7, chlorfluazuron 6.2ppm이었다. 번데기에 대한 미량주사처리에서는 diflubenzuron 0.053, triflumuron 0.230, chlorfluazuron 0.340 $\mu\textrm{g}$/pupa의 {{{{ { LC}_{ 50} }}}}값을 나타내었다.

• 한국응용곤충학회지
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• 제23권4호
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• pp.233-236
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• 1984

본 연구는 경상남도 진주에 위치한 농촌진흥원 해충 시험포장에서 Carbofuran 입제를 본답기에 2회 처리와 농가 관행방제인 살충제 9회 처리간의 벼 해충과 이들 천적의 밀도를 비교 조사하였다. 1. Carbofuran $3\%$ 입제를 기계이앙시 육묘상자 처리와 7월중순 수면 처리등 본답기에 2회만 처리하여도 벼의 주요해충인 멸구 매미충류, 나방류, 굴파리, 총채벌레등의 방제효과가 관행 방제인 살충제 9회 처리와 비등한 경향이었다. 2. 벼 해충의 천적인 거미류와 멸구류의 난기생봉(Anagrus sp.)의 밀도는 Carbofuran 입제 처리가 관행방제보다 2.4배 밀도가 높았다.

• 한국응용곤충학회지
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• 제17권2호
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• pp.99-103
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• 1978

침투성 살충제 Carbofuran의 Capsule 근부처리, 액상근부주변처리 및 수면시용을 실시하였을 때 논거미(늑대거미류와 애접시거미류) 밀도에 미치는 영향을 알아보기 위해 수원과 이리에서 포장시험을 실시하였다. 1. Carbofuran의 처리에 의하여 거미의 밀도가 저하되며 관용방법인 수면처리에 비하여 근부처리의 경우 거미의 밀도가 더욱 낮었다. 2. 액상근부주변처리에 비하여 Capsule 근부처리에서 거미의 밀도가 더욱 낮었다. 3. 근부처리에서나 수면처리에서 약량이 증가함에 따라 거미밀도가 낮어졌다. 4. 무처리에서 거미밀도는 팔굉품종에서 높았고 유신품종에서 낮았으나 약제처리에서 품종간 거미밀도차이는 인정할 수 없었다. 5. 해충의 방제효과가 좋았던 Capsule 근부처리에서 거미 밀도가 낮은 이유는 식물연쇄에 의한 독성 및 살해로 고찰되었다. 6. Carbofuran의 경우 처리방법을 달리하였을 때 거미에 대한 살해를 감소시킬 수는 없을 것으로 사료된다.

• 환경생물
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• 제22권1호
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• pp.12-27
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• 2004

최초의 한국 동굴산 생물인 등줄굴노래기(Antrokorean gracilipes Verhoeff 1938)가 보고된 이후부터 약 70여년동안 출판된 동굴 생물상에 관한 112편의 국내외 논문과 16편의 보고서 그리고 10편의 단행본을 재정리하였다. 지금까지 한국산 동굴생물은 총 4문 10강 31목 94과 257종이 보고되었으며 36개소의 동굴과 4개의 우물에서 87종이 한국동굴(지하)산 모식종으로 기록되어 있다. 한국산 동굴생물은 절지동물류가 241종(93.8％)로 가장 우점하였고, 그 중에서 진정 거미류(Araneae)가 21종의 고유종을 포함하여 29과 97종으로. 가장 다양한 분류군 이었다.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.1-7
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• 2008

In this minireview we focus on how males may exploit female's sensitivity to predation risk in the context of mating. It has been shown in studies on guppies and jumping spiders that in response to altered female behaviors, which are adaptations to the unfavorable environment and a consequence of females' higher sensitivity to predator's presence as well as females' higher predation risk, males can adopt condition-dependent mating tactics. It appears that in such cases males do not modify their reproductive behavior directly in response to their own perception of predation risk, but indirectly in response to changes in female behavior induced by predator presence. It has also been recently shown in crabs that males can exploit female behavior by creating safer habitat spots, which increases the male mating success. Hence all the evidence suggests that males not only respond to female sensitivity to the natural variation in predation risk, but that males can also exploit female behavior by altering the environment. As a logical extension of these findings, we present a hypothesis that in certain conditions males can manipulate the environment in order to increase the predation risk and to induce female behaviors that enhance the male's mating success with the increased predation risk. We propose that such a manipulation to increase predation risk is expected to evolve in males of species with a strong sexual conflict and female-biased predation risk. Although empirical evidence has not been yet shown, initial observations in a water strider species in Korea, Gerris gracilicornis, seem to support this hypothesis.

• 한국발생생물학회지:발생과생식
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• 제24권4호
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• pp.297-306
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• 2020

Repetitive changes in the intracellular calcium concentration ([Ca²⁺]i) triggers egg activation, including cortical granule exocytosis, resumption of second meiosis, block to polyspermy, and initiating embryonic development. [Ca²⁺]i oscillations that continue for several hours, are required for the early events of egg activation and possibly connected to further development to the blastocyst stage. The sources of Ca²⁺ ion elevation during [Ca²⁺]i oscillations are Ca²⁺ release from endoplasmic reticulum through inositol 1,4,5 tri-phosphate receptor and Ca²⁺ ion influx through Ca²⁺ channel on the plasma membrane. Ca²⁺ channels have been characterized into voltage-dependent Ca²⁺ channels (VDCCs), ligand-gated Ca²⁺ channel, and leak-channel. VDCCs expressed on muscle cell or neuron is specified into L, T, N, P, Q, and R type VDCs by their activation threshold or their sensitivity to peptide toxins isolated from cone snails and spiders. The present study was aimed to investigate the localization pattern of N and P/Q type voltage-dependent calcium channels in mouse eggs and the role in fertilization. [Ca²⁺]i oscillation was observed in a Ca²⁺ contained medium with sperm factor or adenophostin A injection but disappeared in Ca²⁺ free medium. Ca²⁺ influx was decreased by Lat A. N-VDCC specific inhibitor, ω-Conotoxin CVIIA induced abnormal [Ca²⁺]i oscillation profiles in SrCl₂ treatment. N or P/Q type VDC were distributed on the plasma membrane in cortical cluster form, not in the cytoplasm. Ca²⁺ influx is essential for [Ca²⁺]i oscillation during mammalian fertilization. This Ca²⁺ influx might be controlled through the N or P/Q type VDCCs. Abnormal VDCCs expression of eggs could be tested in fertilization failure or low fertilization eggs in subfertility women.