• Korean Journal of Medicinal Crop Science
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• v.7 no.1
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• pp.16-21
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• 1999

Seed-propagation of Solomon's seal (Polygonatum odoratum) takes 2 years to shorten the period for becoming a practical method. The experiment was done to establish a proper method of breaking the epicotyl dormancy in bulk seed-propagation. Seedlings with a bulbil were treated with $GA_3$ every 2 days for 4 or 8 days and chilling treatments at $3^{\circ}C$ were enforced for 4, 6, 8 or 12 weeks. Emergence- and growth-related characteristics were examined immediately after the treatments, 3 and 6 weeks later. Rate of cotyledonary sheath rupture immediately after $GA_3$ treatment was greater in its 8-day treatment than in 4-day although its effect disappeared later. However, any epicotyl treated with $GA_3$ solution did not elongate so that new seedlings disemerged over the bed soil. That resulted from not breaking the epicotyl dormancy since $GA_3$ did not rupture all of the cotyledonary sheath formed with several sheets and consequently, the solution did not reach it. The $GA_3$ treatment for bulk seed-propagation, therefore, was impractical method. On the contrary, the chilling treatment was able to be applied to the seed-propagation because of getting the cotyledonary sheath rupture and the epicotyl elongation. Seedling emergence and its growth after chilling treatment were influenced by chilling period although required at least over 6-week treatment for satisfactory results.

• Korean journal of applied entomology
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• v.29 no.2
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• pp.123-131
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• 1990

To elucidate the role of tow environmental factors, temperatures and photoperiod, in diapause induction and development of the dark grey cutworm, Agrotis tokionis B., field and laboratory experiments were implemented. As larvae entered diapause later, the diapause duration became shorter resulting in the synchronization of pupation of the test population. The summer diapause of this insect was assumed to be obligatory because every mature larvae had to experience summer dormant period at all experimental conditions of temperature and photoperiod. It was suggested that the diapause stage could be divided into two different phases in relation to temperature reaction. as the temperatures examined, the duration of diapause was shortened by higher temperature in the early phase, while it was shortened by lower temperature in the late phase. Th diapause period was the shortest under short-day condition (LD 8:16)

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.163-170
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• 2002

In order to analyze the life cycle of A. artemisiifolia var. elatior dormancy and some environmental factors inducing germination of the seeds were examined. The results were as follows : Dormancy of fertile seeds was broken in part within a month after seed collection in case of adequate moisture and alternating temperature was also effective in breaking dormancy. The temperature range, which allow germination was $12^{\circ}C{\sim}32^{\circ}C$. Optimum temperature for germination was $24^{\circ}C$. The seed of A. artemisiifolia var. elatior was light-independent. The difference of storage period appeared to have no particular effect on the viability of seeds at any time during the 9-month storage period. In the increasing temperature(IT) regime, A. artemisiifolia var. elatior seeds started to germinate at $16^{\circ}C$, showing the higher temperature the greater germination rate : the final germination percentage was 99.34%. On the other hand, in the decresing temperature(DT) regime, seeds began to germinate at $20^{\circ}C$ with the 1.34% germination. An induced dormancy occurred at $12^{\circ}C$ making the 5.34% final germination in the DT regime. Low temperature was more effective to break dormancy than higher temperature. Seeds of A. artemisiifolia var. elatior seems to be germinated in mid to late autumn or germination delayed until following spring. The above results suggest these variation of germination response in diverse environmental factors seems to be a physiological strategy to maintain their existence and to reproduce in the extreme thermal variation.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.495-501
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• 1993

This experiment was carried out to find out the dormancy physiology, method of softening culture and evaluation of nutritional value of wild garlic, Ulrung-native Allium victorialis var. platyphyllum. In March, a new bulbs, the shoot and bulbs began to develop until the bulbs showed their complete dormant states in late August. The bulbs renewed to another one in every years. When shoots germinated about $1{\sim}2\;cm$ from mother bulbs, the soft tissues in the mother bublbs was degenerated and finally remained as only fiberous tissues unlike the other bulbaceous plants. There was a high inhibiting activities like ABA in the bulbs. This is believed that this inhibiting substance like ABA in the bulbs is related to the dormancy of wild garlic. Although the immatured bulbs, harvested at May and June, was treated with chilling for 90 days, it didn't germinate their shooting, but the matured bulbs, harvested at July and August, could germinate their shooting over 1 cm in 75 and 60 days chilling treatment, respectively. The shoot elongation was promoted by the longer chilling periods, the later harvesting day and the dark condition. The crude fiber content of leaf and stem increased at more expanded leaf and higher light intensity condition. Since the shoots, grown from germinating to leaf expanding time, had a good quality for food stuff and had less crude fibers, we supposed this period is to be most appropriate for harvesting time.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.111-115
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• 1995

This study was carried out to investigate the effect of some plant growth regulators on the germination and seedling growth of Wasabia japonica Matsum seeds. The seeds were soaked in different concentration of indolacetic acid(LAA), indolbutyric acid(IBA), $GA_3\;GA_4$, Benzyladenine(BA) and kinetin, and the germination percent, the average germination day and the growth of seedlings were measured. The seeds were released from dormancy and the germination percent was considerably increased when the seedcoat was removed. $GA_3,\;GA_4,$ BA and kinetin were effective in breaking the dormancy, but LAA and IBA were not effective. $GA_4$, BA and kinetin were more effective in accelerating germination of dormancy seed than $GA_3$. The applications of BA combined with $GA_3$ l00ppm showed higher germination percent than that of BA alone within the range 50ppm and 100ppm. Root, hypocotyl and petiol of seedling overgrew by the application of $GA_3\;and\;GA_4$. But effects of BA and kinetin were good on seedling growth compared with those of $GA_3\;and\;GA_4$. Therefore, BA and kinetin could be use for dormancy breaking of seed instead of $GA_3$.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.201-209
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• 2004

Overwintering ecology of the peach pyralid moth, Dichocrosis punctiferalis Guenee (Lepidoptera: Pyralidae) was studied in laboratory and in a chestnut orchard in 2001/2002 winter and 2003 spring. All twenty-four female and fourteen male moths were fruit-feeding type which were emerged from the larvae collected at the same chestnut orchard in 2003 winter. Periodical thermal treatment of overwintering larvae at $25^{\circ}C$ revealed that diapause termination of the larval population started from the end of January and was completed until April 20 in southern region of Korea. Pupation of diapause-terminated larvae started from early May and reached to $100\%$ at June 3 in chestnut orchard. Days to pupation of female larvae after diapause termination were 12.5, 8.9, and 7.5 at $20^{\circ}C,\;25^{\circ}C$, and $30^{\circ}C$, respectively. Those of male larvae were similar to those of females. Pupal periods of female were 14.7, 11.8, and 9.0 days at the three temperatures. Moths of the overwintered generation emerged from May 20 to June 28, and reached to $50\%$ emergence on June 8 to 9 under emergence cage. Attraction of the male moths of overwintered generation to sex pheromone traps showed that the date of $50\%$ catches to the traps were June 17, when data from 3 southern regions of Korea were pooled.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.91-91
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• 2017

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.7-13
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• 1989

The present study was carried out to get the basic information for clarifying physiological mechanism of breaking dormancy and sprouting in Panax ginseng roots. Changes in Abscisic acid (ABA) content and Gibberellin (GA) activity were investigated in one-year-old root during stratification at 4$^{\circ}C$. 15$^{\circ}C$. and 15$^{\circ}C$ after 60day-treatment at 4$^{\circ}C$. Sprouting rate at 15$^{\circ}C$ was 35％ in 30days storage at 4$^{\circ}C$ and 100％ in longer than 60days, but there was no sprout in both the constant treatment at 4$^{\circ}C$ or 15$^{\circ}C$ regardless of the treatment period. The longer the period of low temperature treatment. number of days to the first and 50％ sprouting was shortened, and number of days to 50％ from first sprouting was also shortened. ABA content in the upper part of root(contained bud) was gradually increased at both 4$^{\circ}C$ and 15$^{\circ}C$ as the treatment period was extended. and the degree of increase was higher at 15$^{\circ}C$. In the lower part. it showed a slight increase at 15$^{\circ}C$. while showed little change at 4$^{\circ}C$ throughout the treatment period. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$, it was greatly increased in the upper part. while rather slightly decreased in the lower part of root. GA activity in the upper part was gradually decreased at both 4$^{\circ}C$ and 15$^{\circ}C$, and the degree of decrease was higher at 15$^{\circ}C$. In the lower part. it was similar tendency to those in the upper part. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$. it was remarkably increased in both the upper and lower part. The increase was great in the low Rf region, while the decrease appeared relatively in the high Rf region compared to those of 60day-treatment at 4$^{\circ}C$. The above results indicated that the breaking dormancy and sprouting of bud were closely associated with the degree of GA activities in response to temperature condition .during stratification rather than the direct effect associated with the changes in ABA content.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.515-520
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• 2001

To observe the stimulating effect of low dose ${\gamma}$ radiation on the dormancy breaking and growth, microtubers of two potato cultivars (Solanum tuberosum L. cv. Dejima and cv. Superior) were irradiated at the dose of 0.5-30 Gy. Though it varied with cultivars and storage duration, sprouting rate, plant growth and tuber yield were promoted by 2-8 Gy irradiation in microtuber of 'Dejima' stored at low temperature. On the other hand, in microtuber of 'Superior', sprouting rate was promoted by 2 and 4 Gy irradiation, and the growth and tuber yield by 4 Gy irradiation. These results suggest that low dose of ${\gamma}$ radiation could have stimulating effects on the dormancy breaking of microtuber and potato growth.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.45-49
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• 2006

This study has been conducted to find out the possibility of the winter production for pot cultured plants, such as P. sieboldii, P. modesta var. fauriae and D. smilacinum in highland, 800 meter above sea level by early breaking dormancy. Low temperatures for breaking dormancy were treated for 300, 500, 700 and 900 hours under $5^{\circ}C$ in incubators and, then these plants were moved to greenhouse controlled at $10^{\circ}C$ of night temperature. Results showed that P. modesta var. fauriae and D. smilacinum, and P. smilacinum required more than 500 hours and 700 hours of low temperature $5^{\circ}C$ for breaking dormancy, respectively.