• Korean journal of applied entomology
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• v.44 no.2
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• pp.125-130
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• 2005

The ecological characteristics of the specialist insect predator, Oligota kashmirica benefica, were investigated for developing artificial rearing method with special interest on the oviposition behavior, the pattern of adult emergence and temperature in storage, and its effect on the density of the citrus red mite, Panonychus citri. Female beetle oviposited eggs mainly, $95\%$ of the eggs, on the bottom of leaves of the yuzu tree, and $91.3\%$ of them were covered with ecdysis skin of the red mites or the feces of themselves. The rate of adult emergence of the beetle rose up to $86.7\%$ when the horticultural media was provided for pupation from $60\%$ when it pupated in upland soil. Most larvae, $88\%$ of them, were found from the surface to the depth of 2 cm in the horticultural media. The optimum temperature for the storage of the adult beetle was found to be $12^{\circ}C$, at this temperature the 96.7, 73.3 and $70.0\%$ of the beetle survived for 10, 20, and 30 days, respectively. The control effect of the citrus red mite was appeared highest by releasing the beetle at the rate of one beetle against 150 mites.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.277-285
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• 1990

Laboratory and field studies were conducted to investigate the initiation and termination factors for pupal diapause in the Oriental tabacco budworm, Heliothis assulta Guenee. Diapause induction was dependent of photoperiod and temperature experienced by 4th and 5th instar larve. One hundred percent of pupal diapause was obtained when larvae were grown at 10L/14D or shorter and $20^{\circ}C$. But at $25^{\circ}C$ the maximum rate of diapause was only about 85% at 8L/16D, the shortest photoperiod tested in this experiment. Adults, eggs or pupae did not respond to diapause-inducing environmental conditions. The critical photoperiod was 12-12.5 hr at $25^{\circ}C$and 14-14.5 hr at $20^{\circ}C$. In the field-collected sample 100% of diapuse rate was observed on Sept. 20 and thereafter in Suwon and middle part of Korea. Cold temperature treatment was not necessary in the termination of pupal diapause, but accelerated adult development.

• 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).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.232-241
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• 1984

A series of experiments were carried out to know the effects of pollen stage, cold shock temperature and duration, and media for callus and green plant induction in rice anther culture. The results indicated that: (a) uninucleate stage of pollen was the most suitable stage for effective callus induction, (b) cold shock temperature of 8$^{\circ}C$ and 12$^{\circ}C$ was appeared to be proper temperature for callus induction, (c) callus induction rate was increased in the eight to 12 days long cold storage, (d) the medium N6 was better than that of N6D for callus induction, (e) green plant induction was better in both 4$^{\circ}C$ and 8$^{\circ}C$ than that of 12$^{\circ}C$ cold shock, (f) green plant frequency was higher in eight to 12 days long cold storage and (g) green plant frequency was doubled in the MS medium when compared with N6 medium.

• Journal of Forest and Environmental Science
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• v.10 no.1
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• pp.32-37
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• 1994

This study was carried out to clarify the primary hosts of Tetrastichus sp. and its host relationship, development and reproductive capacity. Protopulvinaria mangiferae was parasitized by Aneristus ceroplastae, Microterys flavus, Coccophagus hawaiiensis. All of these primary parasitoid were attecked by the hyperparasite Tetrastichus sp.. Tetrastichus sp. was bound to be a solitary ectoparasite. Eggs were laid on the pupa of the primary host or attached to the inner surface of the integument of the scale insect. Threshold of the development and thermal constants for completion of immature stages were $9.8^{\circ}C$ and 272 day-degrees, respectively. At $25^{\circ}C$ the life span of both sexes without any food or with water were very short as compared with that with honey. After a pre-oviposition periods of about one day they laid on overage 220 eggs each, almost all during the first half of their life. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase(r) were calculated as 99.6, 32days and 0.142 per female per day respectively.

• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.59-66
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• 1992

1-4령 저염인공사료 공동육＋5령 뽕잎육(농가개별육)$\longrightarrow$일주일 양잠에 적합한 광식성 누에품종육성에 필요한 기초지식을 얻기 위해 광식성유전자의 검색, 유전현상, 특성, 광식성계통 작출, 실용광식성 누에 품종육성방법 등에 대하여 소고하였다. 1. 광식성 유전자의 검색은 의잠을 사용하는 것이 가장 성력적이고 편리하며, 또한 섭식성을 정확히 파악할 수 있다. 2. 광식성 누에의 LP-1 사료에 대한 섭식성은 사육온도, 광조건, 발육단계 및 절식에 의하여 크게 영향 받지 않는다. 3. 광식성 유전자는 열성형질이며 1개의 주유전자와 수개의 수식유전자로 구성되어 있는 것으로 추찰된다. 4. LP-1 인공사료에 첨가한 morin 및 n-hexacosanol의 누에 섭식촉진효과는 미소하였으나, 상엽분말 첨가로 인한 누에 섭식촉진효과는 매우 양호하였다. 5. 광식성누에의 섭식성은 어분 및 효모에 의해 영향받지 않았다. 6. 섭식저해물질인 brucin 및 salicine은 정도의 차는 있으나 광식성누에의 섭식성을 저해하였다. 7. 광식성 및 비광광성누에의 LP-1 인공사료에 대한 섭식성의 차이는 누에의 두부에 있는 감각기관의 형태적 차이 때문이 아니라 기능적 차이에 기인하는 것으로 추찰된다. 8. 광식성 육성소재창출은 광식성유전자의 도입육종에 의해 가능하다. 9. 실용 광식성 누에품종육성을 위해 광식성검정에 적합한 인공사료를 사용하고, 실용형질이 우수하면서도 광식성유전자를 가진 계통을 선발, 교잡 또는 계통육성법에 의해 실용형질 및 섭식성을 개량하여 육종 목표를 달성하는 것이 최선책으로 생각된다.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.56-61
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• 1989

In the present paper, we intented to analyze and to compare the different seed dormancy of two legume plants, Albizzia and Cercis. We found two different types of seed dormancy: one type of dormancy in Albizzia seed was caused by the water impermeability, and other type of seed dormancy was found in Cercis and it was induced by inhibitors. We confirmed that the extract substances from Cercis seed seemed to have strong regulational functions on the inhibition of seed germination and primary root growth of lettuce seed.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.861-873
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• 2017

The present study was conducted to investigate the developmental characteristics of Propylea japonica Thunberg (Coleoptera : Coccinellidae), a predator of aphids under laboratory conditions. The development times of the egg and immature stages of Propylea japonica were investigated at ten constant temperatures(15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5, 35 and $38{\pm}1^{\circ}C$; 14L:10D; $60{\pm}5%$ RH). Development time was longest at $17.5^{\circ}C$. The developmental periods of P. japonica from the time of egg oviposited to adult emergence was 36.9 days at $17.5^{\circ}C$, and it decreased ash temperature increasing. Threshold temperature of development and degree days of the P. japonica from egg to adult were $11.9^{\circ}C$ and 196.0 respectively. The Briere 2 and Lactin 2 modes were best fitted for all development stages. The distribution of completion of each development stage was explain relatively well that 2-parameter, 3-parameter and Logistic model except egg and pupal stage.

• Korean journal of applied entomology
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• v.26 no.3 s.72
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• pp.139-144
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• 1987

This study was carried out to investigate the incidence and termination of pupal diapause in the fall webworm, Hyphantria cunea Drury. Larvae obtained from overwintered pupae were reared on Morus alba leaves at $25{\pm}1^{\circ}C$ with the relative humidity of 60% or higher in a laboratory. The critical photoperiod for pupal diapause initiation is between 14hrs and 14hrs & 30 minutes at $25{\pm}10^{\circ}C$. The developmental period of larvae was shorter under longer photoperiod at $25{\pm}1^{\circ}C$. In nature. diapause termination seems to begin in late December. The diapausing pupae did not emerge at all when they were transferred to a favorable environment before the time.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.15-47
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• 2021

Sex pheromone is used for chemical communication for mating in a species-specific manner in insects. Insect antennae possess sensory receptors specific to sex pheromone components and generate receptor potential to be perceived by the brain to evoke mating behavior. The sex pheromones have been used for monitoring specific species of insect pests to predict their subsequent occurrences based on a temperature-dependent growth model. Sex pheromones are also used for controlling pest insects using several different strategies such as mass capture, lure-and-kill, or mating disruption. This review explains the sensory physiology and insect pest management techniques related with sex pheromone.