• Horticultural Science & Technology
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• v.19 no.4
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• pp.488-494
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• 2001

Seedlings of strawberry, 'Reiko' were planted in plastic pots of 24 cm in diameter in the middle of September in 1995, 1996, and 1997. Ten plants were transferred to greenhouse with artificial illumination at 5-day interval from late September to late January. The deepest dormancy of 'Reiko' in Daegu area was found to be on November 5, October 25, and October 31 in 1995, 1996, and 1997, respectively. The time for moving plants to make the plants grow in semi-dormant state in the greenhouse occurred between Nov. 10 and Nov. 20 in both 1995 and 1996, and between Nov. 10 and Nov. 30 in 1997. The time passing approximately 100-200 cumulative hours of exposure to below $5^{\circ}C$ canopy temperature from the peak dormancy, which is required for breaking dormancy of 'Reiko', was between November 16 and 25 in 1996, and November 24 and December 5 in 1997. 'Reiko' yielded high every year when seedlings were moved into greenhouse during the period of October to November. The plants gave good response to forcing culture under lighting. The right time for moving plants into greenhouse in semi-forcing culture appeared to be the time passing 50-150 cumulative hours of exposure to below $5^{\circ}C$ canopy temperature from the peak dormancy.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.111-117
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• 1974

The electron micrographs of the larval brain of the silkworm. Bembyx mori. show that median neurosecretory cell of diapause-egg producer may participate in the production of lipo-granules and that of non-diapause egg producer may do in the production of electron-translucent vesicles. It was found that ribosome-like particles of diapause-egg producer gradually developed into highly dense particles and came into line along the smooth-surfaced endoplasmic reticulum. They finally became lipo-granules.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.143-150
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• 1997

In order to produce young leaf of butterbur(Petasites japoflicus MAX.) in early spring, the planting date and relationship between abscisic acid(ABA) content and dormancy were investigated. Under open field condition, the dormancy of rootstock was initiated in the beginning of October, was the deepest in the middle of November and was completely broken in the end of December. When those periods were converted by the low accumulation hour below 5$^{\circ}C$, 900 hours were required approximately. This means that the rootstock needs for dormant breaking necessitates under the low temperature. In relationship between growing period and ABA content, the ABA in root-stock did not exist during maximum growing period, from April to September. This means that the ABA together with other substances in rootstock can be transferred to the shoot part with sprouting. While shoot part withered by decreacing the open field temperature since October, the ABA intiated to exist in rootstock. This means that the ABA in the shoot part can be transferred to the rootstock part. Therefore, it was concluded that the ABA which has been known that inhibiting growth and inducing dormancy was closely related with dormancy of rootstock.

• Journal of Sericultural and Entomological Science
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• v.24 no.2
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• pp.55-72
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• 1983

These studies were done to find out any difference, ultrastructural, physical or chemical, between the shells of diapausing and non-diapausing eggs of the silkworm, Bombyx mori L. 1. From the electron-microscopic observation, the egg shells have four distinctive layers. In addition to the four layers, the shells in the diapausing eggs has another layer with low electron density on its surface. 2. The permeability of the egg shell to hydrochloride was much lower in diapausing egg than in non-diapausing egg. Also the permeability changed in the opposite directions with the egg age: the diapausing eggs decreased while non-diapausing ones increased. 3. The permeability increased when the diapausing egg shell was treated with HCl. When they were treated with ether, however, the increase in permeability was much smaller. It seems there was an ether soluble material involved in the content of the egg shell. 4. The diapausing eggs were also much more resistant to desiccation than the non-diapausing ones. The former, when treated with HCl or chilling, became less resistant to desiccation. 5. The positive histochemical response of the egg shell to PAS-Alcian blue and protein stainings suggests presence of abundant proteins and carbohydrates in the egg shell. On the other hand, the staining response to lipid was more positive in the inner layers than in the outer layer of the shell. 6. The egg shell adhesives seems to be mucopolysaccharides produced by colleterial glands, since the oviposited eggs showed a positive responses to carbohydrate and negative to lipid-staining chemicals, but not the mature oocytes in the ovarioles. 7. There were two bands on the electrophoretic pattern of the SH proteins extracted from the egg shells both in the diapausing egg and non-diapausing one: a slow moving major component and a fast moving minor one. However, the electrophoretic mobility showed a difference in the minor components between them. It is evident that the fast moving minor one of non-diapausing egg ran a little further than that of diapausing egg. 8. In amino acids analysis, no significant differences were found in their composition between diapausing and non-diapausing egg and SH proteins contain relatively more glycine and less cystine.

• 한국해양학회지
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• v.26 no.4
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• pp.304-312
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• 1991

The distribution of dinoflagellate cysts have been investigated at 6 stations in Masan Bay, a well known area of red tide in the southern coastal waters of Korea, from May 1986 to March 1987. During the study, a total of 11 species in dinoflagellate cysts were isolated from surface sediments, representing 6 genera, 9 species and 2 unidentified species. The standing crops of dinoflagellate cyst varied extensively by month and station; ranging from 48 to 1,279 cells/cm$^3$ and showing major peaks in July. August and February. At stations, the distribution was most abundant at st. 4 (mouth of the bay), whereas it was very low at st. 1 (inner bay), where motile cell's blooms occur throughout the year. Thus, It is speculated that the distribution between the plankton and cyst populations of dinoflagellates show the different temporal and spatial patterns in a semi-closed bay like this survey area.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.105-111
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• 1999

The objectives of this research were to determine growth characteristics of commercial cultivars of strawberry grown in Korea, then to differentiate each cuitivar into cropping system based on degree and duration of domancy and to determine starting date of greenhouse heating as forced culture. The date of floral differentiation on cuitivars such as 'Chodong' 'Shuko' 'Nyoho' was from Sep. 20 to 22. However those of 'Toyonoka', 'Reiko', 'Hokowase' etc. were Sep. 26 to 30 and that of 'Morioka(No. 16)' was Oct. 19. It indicated that the cultivars with short dormancy period 'Nyoho', 'Reiko', 'Toyonoka' etc. were suitable for forcing culture, cultivar with ordinary dormancy period such as 'Suhong' was for nearly forcing culture, cultivar with long dormancy period such as 'Hokowase' was for semi-forcing culture, and cultivar with extreamly long dormancy period such as 'Morioka (No. 16)' was for retarding culture.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.6 no.12
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• pp.83-89
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• 1985

겨울동안 딸기재배의 작형은 딸기가 휴면기간이 매우 짧으면서 꽃눈분화가 조속히 이루어지는 품종을 선택하여 재배하는데 일반적으로 촉성, 반촉성 및 억제재배 등이 있으며 촉성재배는 비닐이나 섬피 등 보온을 실시하여 11월$\~$1월부터 2$\~$3월에 걸쳐서 수확을 목적으로 재배하는 작형이다. 반촉성재배는 촉성재배보다 보온을 늦게 시작하여 촉성재배의 수확말기인 3$\~$4월에 수확하여 출하하는 재배형이다. 억제재배에서와 같이 보통육묘를 실시해서 월동시킨 다음 봄에 생육이 시작하기 전인 2월 하순경에 모를 굴취하여 0$^{\circ}C$내외의 환경하에 장기간 저장하여 강제휴면을 시켰다가 8$\~$9월에 정식한 후 10$\~$11월경에 수확하는 작형이다. 이들 기본작형을 변형시켜 다시 세분화된 재배형으로 나눌 수도 있다. 본란에서는 현재 수익성이 높고 비교적 안전한 딸기 반촉성재배에 대하여 설명하고자 한다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.198-199
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• 2000

유독 와편모조 Gymnodinium catenatum Graham은 인간과 해양동물에 마비성패독(PSP) 발생의 원인이 되는 신경독을 생산한다. 1976년에 스페인 북서쪽 해안에서 G. catenatum에 의한 PSP 발생이 처음으로 알려졌고(Estrada et al. 1984) 특히 호주와 스페인 등지에서 문제가 되고 있다. 한국에서도 1991년 10월 진해만에서 채집된 저질로부터 처음 휴면포자가 발견되었고, 휴면포자량은 전체 와편모조류 중 0.9~l.7%를 차지하였다(Kim et al., 1996). 1996년 9월에는 영양세포가 7,250 cells/$\ell$로 진해만의 수정리에서 출현하였고, 1997년 5월에는 550 cells/$\ell$로 출현하였다(김과 신, 1997). 이는 Alexandrium속이 주로 봄철에 대량발생을 하여 패류 독화가 문제되는 것에 반해 C. catenatum은 봄, 가을에 출현함으로써 봄철에 이어 가을철에도 패류독화가 문제될 수 있다는 것을 의미한다. 따라서 본 연구에서는 서해안 및 남해안에서 분리된 지역분리주의 PSP 생산성을 검증하고, 지역 개체군의 독조성을 비교하여 지역 독화의 가능성을 예측하고자 한다. (중략)

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.35-43
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• 2015

To assess the dormancy associated weedy risk of the F1 hybrid generated by hybridization between Brassica juncea (maternal) and Brassica napus (paternal), seed germination, dormancy and longevity were examined sequentially after seed harvest. The F1 hybrids exhibited the intermediate characteristics of their parents in seed germination and dormancy with relatively high dormancy rate of 41.1%. In summer, F1 hybrid seeds buried in the 3 cm soil exhibited greater viability (52.4%) than those in the soil surface with greater seed longevity (74.6%) than its maternal (63.3%) and paternal (33.7%) parents at 100 days of over-summering in soil. In winter, F1 seeds buried in the soil surface were more viable than those in the 3 cm soil with greater seed longevity (83.5%) than its maternal (39.0%) and paternal (71.7%) parents at 100 days of over-wintering in soil. Therefore, it is concluded that F1 hybrid resulted from gene flow from OSR to mustard has high seed dormancy and longevity during summer and winter, suggesting its weedy risk potential. Further studies are required to examine the reproductivity and fitness cost of F1 hybrid to make a clearer conclusion of its weedy risk.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.91-95
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• 2005

This study was conducted to investigate the morphological characteristics, overwintering sites and behavior for each stage of Oligota kashmirica benefica (Coleoptera: Sthphylinidae). Egg was oval type, yellow, 0.3 mm size. Larva exuviated 3 times and the last (3rd) instar, length 1.6 mm, wide 0.4 mm, became dermata pupa in soil. Adult was lightish dark-brown, and coriaceous forewing covered a half of abdomen. O. kashmirica benefca mainly overwinters with adult at Japanese cedar (Cryptomeria japonica) windbreaks of orchards, but it did not diapause in greenhouse during winter.