• Korean journal of applied entomology
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• v.38 no.3
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• pp.255-260
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• 1999

Pathogenicity and multiplication of entomopathogenic nematode, Steinernema carpocapsae Weiser, ere analyzed in two insect hosts, Spodoptera exiga (Hubner) and Sp. litura(Fabricius). The estimated ${LC}^{50}s$(lethal concentration of the infective juveniles to kill 50% of the host insect population) were not different between tow insect species or among their developmental stages on the filter paper assay, thought the actual numbers of the infected nematodes were varied among them. The significant variation, however occurred in nematode multiplication between tow inset hosts. Temperature also gave sosignificatn effect on nematode multiplication rate that it took 6 days after infection at $25^{\circ}C$, but did 12 days at $20^{\circ}C$ to show the maximal nematode population peak($\approx$500,000 infective juveniles(IJ) in a 5th instar larva of Sp. litura and $\approx$-100,000 IJ in a 5th instar larva of Sp. exigua).

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.1-8
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• 2013

This study was conducted for investigation of habitat and development of indoor-rearing conditions of peacock butterfly, Inachis io (Linnaeus). Three different region, Mt. Kwangduk-san, Mt. Hae-san and Mt. Taebaek-san in Kangwon-do, was selected for investigation of domestic distribution and ecological environment of peacock butterfly. In result, there are many butterflies in the only two region, Mt. Kwangduk-san and Mt. Hae-san. On 16th April, 4 overwintered butterflies were observed in Mt. Hae-san. At the end of June and early in July, 51 individual next generation's butterflies were observed in Mt. Kwangduk-san and Mt. Hae-san. For development of indoor-rearing conditions, collected each 15 male and female peacock butterflies was reared in a room condition. Female butterflies laid eggs in the egg cluster on the underside of host-plant's leaves, Urtica angustifolia Fisch., in the ovipositioning room. We took 11 egg cluster with average $404.6{\pm}23.6$ eggs. Hatchablity of eggs was 92.3%, and the eggs hatched within $5.1{\pm}0.9$ days from the day of oviposition under high temperature, long day condition($25^{\circ}C$, 14L:10D). The larval period was $18.3{\pm}1.0$ days under high temperature, long day condition($25^{\circ}C$, 14L:10D), showing 81.0% pupal ratio. The head width of each developmental larval stage were $0.37{\pm}0.01mm$(1st instar), $0.66{\pm}0.02mm$(2nd instar), $1.07{\pm}0.05mm$(3rd instar), $1.81{\pm}0.07$(4th instar), $2.76{\pm}0.08$(5th instar). The pupal period was $8.4{\pm}0.6$ days, and the emergence rate was 87.5%.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.119-120
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• 2003

우리나라에 분포하는 모자반류는 모두 28종으로 알려져 있으며 (이와 강 2002) 이 가운데 식용으로 이용되는 것은 모자반 (S. fulvellum)이 대표적이다. 모자반의 양식은 주로 서남해 지역에서 이루어지고 있으며 이들의 종묘생산은 자연에서 생식기탁이 성숙되는 4-5월경에 이루어지는데, 유배의 대량 방출을 위한 성숙 모조의 다량 확보가 어렵고 일시에 유배의 대량 방출을 유도하기 위한 성숙 유도 기법의 연구는 전무한 실정이다. 따라서 이 연구에서는 모조의 실내 배양을 통하여 유배의 대량 방출을 위한 성숙 유도 기법과 배양 조건별 엽체의 성숙 및 난방출율을 구하여 모자반의 조기채묘에 유용한 자료로 사용하고자 하였다. 또한 채묘된 발아체의 초기생장에 필요한 최적 배양 환경을 구명하고자 하였다. 모자반 모조는 전남 진도군 조도 지역의 수심 3-5m에서 채집하였으며, 채집 즉시 실험실로 운반하여 유수식 사육 수조에 수용하였다. 성숙 유도는 20$\ell$ 플라스틱 bottle을 사용하였으며, 성숙률의 정량화를 위하여 암생식기탁을 절단하여 수차례 멸균해수에서 세척후 멸균된 5cm직경의 petri dish에 멸균해수20$m\ell$와 함께 수용하여 Multi-chamber incubator에서 배양하였다. 배양조건은 5개 온도조건 (5, 10, 15, 20, $25^{\circ}C$)과16:8h의 장일 광주기 조건으로하였으며 조도는 80 $\mu$molm$^{-2}$ s$^{-1}$로 하였다. 모든 실험구는 3반복 실험하였으며 2일 간격으로 생식기탁의 생장 및 성숙 그리고 난방출 여부를 현미경하에서 측정하였다. 난이 방출된 모조로부터 유배를 분리하여 3개 조도 구간 (30, 60, 100 $\mu$molm$^{-2}$ s$^{-1}$)과 5개 온도 구간 (5, 10, 15, 20, $25^{\circ}C$)의 조합인 15개 배양 조건하에서 엽체의 길이생장을 측정하였다. 생식기탁으로부터 난의 방출은 15$^{\circ}C$와 2$0^{\circ}C$ 조건에서 배양 2일후부터 방출되기 시작하였으며, 배양 9일후 2$0^{\circ}C$ 조건에서 가장 높은 96.7$\pm$5.8%의 난방출율을 보였다. 또한 15$^{\circ}C$ 조건에서는 배양 9일후 76.7%의 난방출율을 보였다. 1$0^{\circ}C$와 $25^{\circ}C$ 조건에서는 배양 11일까지 36.7%의 난방출율을 나타내어 온도 조건에 따라 난방출 비율에 차이를 보였다. 따라서 이러한 실내 배양 결과를 다량의 모조를 조기에 성숙시키기 위해 모조 수용 수조의 수온을 자연수온보다 2~5$^{\circ}C$ 높은 12~15$^{\circ}C$ 조건으로 유지하여 15일간의 수조 관리 후 모조의 대량 유배 방출을 유도할 수 있었다. 모조 성숙을 위한 사육 수조의 수온을 2$0^{\circ}C$ 이상으로 가온할 경우 엽체의 끝녹음을 유발하였으며 가온에 따르는 가온 비용이 수반되므로 엽체의 난방출율이 70% 이상에 도달하는 15$^{\circ}C$ 조건으로 유지하는 것이 경제적일 뿐만 아니라 엽체의 건전도 유지에도 바람직하였다. 유배의 초기생장은1$0^{\circ}C$와15$^{\circ}C$의 온도조건에서 길이생장이 빠르게 증가하여, 배양 35일 후 15$^{\circ}C$와 60 $\mu$molm$^{-2}$ s$^{-1}$의 조건에서 3.9$\pm$0.2mm로 가장 높은 값을 나타내었다. 엽체의 초기 길이생장은 15$^{\circ}C$, 60 $\mu$molm$^{-2}$ -s$^{-1}$의 조도 조건에서 가장 우세하였으며, 다음으로 30과 100 $\mu$molm$^{-2}$ s$^{-1}$의 조건 순으로 나타났다. 2$0^{\circ}C$와 $25^{\circ}C$의 온도 조건에서는 각각 1.8~2.1mm로 길이생장에 있어 유의한 차이가 없는 것으로 나타났다.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.63-70
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• 2012

This study was conducted to investigated the distribution, ecological character and life cycle of Black Soldier Fly(BSF), Hermetia illucens, to determine effects of BSF on composing ability to the livestock feces. The distribution of BSF was defined in all parts of the country in Korea. Its main habitat was found to be areas near cattle sheds, feces sheds, living waste dump grounds, and food waste dump grounds. Excellent species of the bio-conversion using the livestock feces were selected out of two kinds of solider flies(Hermetia illucens and Ptecticus tenebrifer). And effects of BSF on composing ability to the livestock feces were pig feces 0.5 g, cattle feces 0.43 g and chicken feces 0.3 g per a larvae of BSF. In the examination of the ability of BSF to decompose food waste, volume of the livestock feces decreased by weight pig feces 77, cattle feces 83.62 and chicken feces 80%. Observed characteristics of BSF larvae and pupae stage were by developmental stage may be summarized as follows: size and length of larvae and pupae of BSF were higher than in pig feces and mixed sawdust treatments. In order to develop artificial indoor rearing techniques, The pupation and emergence rate were not visible the difference but important factor of the mating and egg-laying was a sun light. And it was visible the difference in mating ratio. Mating rate of H. illucens by seasonal change was the highest from May to July. Mating mostly occurred between 10 : 00 and 12 : 00 during which light intensity is high. As the egg-laying medium for artificial egg collection, calf feed and food waste were most effective. The ratio of egg-laying medium is waste food : sawdust(1 : 1) in volume. For egg-laying materials, flower foam and wood with holes were used; holes sized 3 ~ 5 mm in diameter, 7 ~ 10 mm in depth were most preferred for egg-laying.

• The Korean Journal of Malacology
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• v.30 no.4
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• pp.303-309
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• 2014

The development of Japanese geoduck, Panopea japonica, grown under culture conditions, has been examined through the morphological characteristics in fertilized egg, larvae and juvenile. Gametes were stripped from ripe broodstock and placed into two separate containers. Eggs were washed through a $40{\mu}m$ sieve and fertilized with dilute sperm solution. Developing larvae were maintained at $19{\pm}1^{\circ}C$. Fertilized eggs with $81.6{\mu}m$ diameter developed to trochophores within 14 h and to D-stage larvae ($116{\mu}m$ shell length) within 27 h. Larvae were spontaneously settled at shell length of $311{\mu}m$ after 20 days. The hatching from fertilized eggs and larval rearing were normally available in $18.5-21.5^{\circ}C$, and the growth was good in a cashmilon substrate, as well as sand. After rearing of day 108 from metamorphosis, the shell length of juvenile P. japonica reached 13 mm, and growth rate of shell length of the juvenile was $117.5{\mu}m/d$.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.61-65
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• 2005

Egg-forming and preservation methods for the indoor-rearing system of the emma field cricket, Teleogryllus emma, were investigated. The oviposition preference experiment on different mats, soil(natural oviposition mat) and $oasis^{\circledR}$(artificial oviposition mat), showed that T. emma preferred to oviposit on the $oasis^{\circledR}$. On the other hand, $oasis^{\circledR}$ had more inactive number of eggs laid per female and hatchability than another. However, the number of eggs laid per female and hatchability within 50 days after emergence were better than soil. The experiment on the hatching of the eggs showed that eggs could be stocked at $10^{\circ}C$ for 40 days with 14 day pre-period after laying, representing $62.1\%$ hatchability, when considering generation shortening. On the other hand, When it had been kept in cold storage for 90 days at $7.5^{\circ}C$ with 14 day pre-period after laying it, appeared to be the most suitable for long period-storage method by hatchability $65.1\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.45-49
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• 1972

The following are some results obtained from a series of experiments in rotifer culture and its usage for the food of tiny fish fry: 1, Outdoor concrete ponds, each being $16m^2$, were used to culture the rotifers, Brachionus calyciflorus, and Filinia longiseta. Brachionus calyciflorus usually attained the population of about 100 individuals per ml of pond water. Dipterex was usually applied to control Daphni,a and other crustaceans that generally appear and feed on rotifers. A concentration of 0.16 to 0.2 ppm in the pond water was sufficiently effective to control these natural enimies of rotifers. Poultry dung was very effectively used to multiplicate rotifers. The fertilization ratio was about 8 kg each pond with 30cm depth of water. 2. The tiny rotifer, Filinia longiseta attained a very high population density of about 1,000 individuals per ml of pond water, but they were very sensitive to dipterex, and for this aspect future investigation may be needed. 3. In the outdoor ponds, the multiplication of rotifers significantly decreased when the water temperature falls to about $20^{\circ}C$ in autumn. 4. In the laboratory room, unicellular planktonic algae such as Scenedesmus or Chlorella, as the food of rotifers, were collected from the outdoor ponds by dipping them together with water, and were effectively used for the culture of Brachionus calyciflorus. If the planktonic algae are cultured in specially designed containers, the sun-light would be the most effective means as the source of light. 5. Brachionus calyciflorus cultured in the outdoor ponds by the dipterex controlled method was highly efficient to rear the early fry of marble gourami. The dipterex content mixed in the water to control the crustacean emmies of rotifers sieved no harm to the gourami fish fry.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.355-362
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• 2019

Cotesia glomerata L., an internal parasitoid wasp, attacks the larvae of both the cabbage white butterfly (Artogeia rapae L.) and the diamondback moth (Plutella xylostella L.). It can be utilized as a natural biological enemy to control these two insect pests in the summer cabbage fields of the Korean highland areas. The developmental response and sex ratio of C. glomerata to various temperatures and its longevity were examined in the laboratory. The egg-to-larva and pupa stages of C. glomerata were 12.1 ± 2.1 and 6.4 ± 1.8 days, respectively, at 20℃, The developmental threshold for egg-to-larva and pupa stages were 7.7 and 8.5℃, respectively. The sex ratios of C. glomerata when reared under various temperatures were 61.0 ± 4.5% at 15℃, 44.2 ± 1.0% at 20℃, and 39.0 ± 2.3% at 25℃, and the incidence of females increased as the temperature decreased. The longevity of C. glomerata when fed a 10% sugar solution was 20.4 ± 0.2 days, while in adults without any feed, the longevity was 3.6 ± 0.1 days. Indoor reared C. glomerata adults were released into cabbage fields from 2007 to 2018, in early August of each year, and the outdoor parasitism rates were surveyed. The parasitism rates were found to increase gradually as the year passed (Y = 0.2696X + 2.8633, R² = 0.3994). The highest parasitism rate was observed in 2013 at 7.6%, and the lowest was in 2018 at 6.5 %. These results could be used as basic information for biological control of kimchi cabbage pests at highland fields.

• Journal of Aquaculture
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• v.17 no.3
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• pp.180-186
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• 2004

This study was carried out to obtain the fundamental data for the mass seedling production of grunt, Hapalogenys nitens in terms of the natural spawning and some characteristics of the eggs spawned. The wild grunt were reared at indoor tanks for three years. The adults spawners were 34.0∼44.0 cm (38.6$\pm$4.0 cm, n=7) in total length, 1.00∼2.23 kg (1.62$\pm$0.50 kg, n=7) in body weight. Spawning were observed 9 times from September 22 to October 1, 2000 and 37 times from August 22 to October 3, 2001, with a water temperature range of 19.8$\pm$28.5$^{\circ}C$. The total number of eggs collected was 2.29${\times}$10$^{7}$ (1.7${\times}$10$^{3}$/ml). The relative proportion of floating eggs to total eggs was 41.7%. The fertilization rate of floating eggs was ranged between 85.0 and 99.9% and the hatching rate was ranged between 2.9 and 93.0%. Fertilized eggs were buoyant and spherical in shape, and were 0.85∼0.98 mm in diameter. Each egg contained 1-5 oil globules which were, 0.18∼0.25 mm in diameter. The incubation time from fertilization to blastodisc formation was 10 minutes, to blastula was 3 hours, and to the hatched larvae at 26$^{\circ}C$ was 20 hours 30 minutes. The newly hatched larvae attained total length of 1.81$\pm$0.18 mm. The time required from fertilization to hatching was 31∼34 hours at 23$^{\circ}C$ and 17∼20 hours at 29$^{\circ}C$.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.423-429
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• 2021

The ovipositional characteristics of the endangered species Prosopocoilus astacoides blanchardi was investigated for indoor mass-rearing. This insect required 3 weeks or more for mating after emergence when introduced at the 1:1 ratio of male to female. Among temperatures studied at 16, 20, 24, 28, and 32℃, the pre-ovipositional period of P. astacoides blanchardi was longest at 16℃ with an average of 109 days after emergence, while it was shortest at 32℃ with an average of 59.4 days. The number of eggs laid at 24℃ was highest with an average of 40.6 per female. The average lifespan of adults at 16℃ was 208.8 days for males and 263.9 days for females, while at 32℃ 96.1 days for males and 130.3 days for females. The number of laid eggs was dependent on insect rearing chamber size. The oviposition-trees did not significantly (P > 0.05) affect the number of laid eggs and ovipositional period. The results of this study could be used as rearing data for the restoration and mass propagation of the endangered species P. astacoides blanchardi.