• The Korean Journal of Zoology
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• v.32 no.1
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• pp.1-8
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• 1989

Non-diapausing larvae and diapausing pupae of Pieris rapae L. were treated with 20-HE and JH, and the concentration of 20-HE and JH in body were also measured to determine mechanisms of diapause induction and termination. When early last instar larvae of non-diapausing stage were injected with 20-HE or JH-I, diapause was not induced in both cases. 20-HE concentration of pre-diapausing last instar larvae was very low, and 20-HE peak of non-diapausing two-day-old pupae was not present in diapausing pupae. There was no difference in concentration of JH-I between diapausing and non-diapausing stages. When early and late diapausing pupae were injected with 20-HE, JH-I, or JH-III. diapause was terminated by 0.1-0.5 $\mu$g of 20-HE, but not by JH-I, or JH-III. The above results indicate that diapause of Pieris rapae was induced by decrease of 20-HE concentration and also terminated by gradual accumulation of 20-HE during diapause process.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.200-201
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• 2000

와편모조류의 대부분은 생존에 불리한 환경조건이 되면 저질에 침적되어 휴면포자의 형태로 휴면시기를 보내다가 온도, 광, 산소, 영양염 등의 환경요인 변동과 내재적 주기에 의해 발아가 유도된다. 이러한 휴면포자는 "개체군 씨앗 "으로서 지역적 적조발생의 잠재력이 되는 것으로 시사되어 왔다. (중략)어 왔다. (중략)

• Korean journal of applied entomology
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• v.59 no.3
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• pp.185-202
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• 2020

The diapause induction season in Ostrinia furnacalis (Lepidoptera: Crambidae) was estimated in Suwon. Three batches of adult generations were observed, the first one from early May to early July, the second from early or mid-July to early or mid-August, and the third from mid-August to October. In outdoor larval rearing, colony rearing occurring from mid-July to mid-August produced both non-overwintering and overwintering larvae, whereas late-reared colonies produced only overwintering larvae. Larvae collected during July and August in maize fields produced both non-overwintering and overwintering larvae, whereas late-collected larvae produced only overwintering larvae. The results indicated that O. furnacalis has a bi- or trivoltine complex life cycle in this area. In the laboratory, when larvae of all instars within 9 h after molting were first treated to a diapause induction condition (11:13 h = light:dark photoperiod and 20℃), almost all larvae were induced to diapause. However, when similar treatments were conducted age-specifically for the 5th instar larvae, diapause induction rates in 3- and 4-day-old larvae of the 5th instar decreased. In contrast, when larvae were subjected to the diapause induction treatment only during the periods from the hatching stage to the 2nd, 3rd, and 4th instar, almost all larvae were not induced to diapause. The results suggest that the early age of the 5th larval instar is the last stage for sensitivity to diapause induction stimuli. In the diapause-induced larvae, hemolymph trehalose content increased and body supercooling points dropped, compared with those in non-diapause larvae.

• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.61-66
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• 2002

Double cropping system in a year in Kyoho grapes (Vitis labruscana L.) has currently been attempted in the plastic greenhouse. One of the problems in double cropping system is the promotion of bud break in summer season and shoot fertility. Effects of the control of soil moisture tension near the root zone and treatments of bud dormancy breaking agents on bud breaking in summer were examined to promote the bud break for the second fruiting. The lignification of shoots was induced in July or August by the control of soil moisture tension in root zone environment. The first shoot growth was almost the same as that in common plastic greenhouses. The highest bud break value appeared in the plot of cyanamide chemicals mixed with merit blue as over 75% bud break rate. The bud break rate in the discontinuing plot in irrigation showed significantly higher in bud break than that in the continuing plot in irrigation. Despite of the final high bud break rate, the time of bud break was irregular.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.10-10
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• 2023

투구꽃속(Aconitum L.)은 미나리아재비과(Ranunculaceae)의 가장 큰 속(Genus) 중 하나로 300-400 여종(Species)이 북반구 온대지역에 분포한다(Tamura, 1993). 둥근 투구모양의 꽃받침이 특징적이며, aconitine과 같은 알칼로이드 성분을 함유하고 있어 전통적으로 약용소재로서 활용되었다(Khorana, 1968). 세뿔투구꽃(Aconitum austrokoreense Koidz.)은 한국 경상도, 전라남도에만 국지적으로 자라는 한국 특산식물이자, IUCN에서 CR(Critical Endangered) 등급으로 지정된 희귀식물이다. 이 종은 다년생이지만, 서식지에서 개체수가 적거나 유묘의 발견이 어려운 등 자생지 축소 및 절멸의 우려가 높다. 세뿔투구꽃을 보호하고 종을 보존하기 위해서는 종자 발아 · 휴면에 대한 지속적 연구와 종자번식법의 개발이 필요하다. 본 연구에서는 세뿔투구꽃의 종자의 휴면유형을 분석하고 호르몬에 의해 휴면타파를 유도하였으며, 특히 발아 2단계에서 일어나는 생리적 변화를 단백질체학적 관점에서 분석하였다. 세뿔투구꽃 종자는 미발달된 배를 가지고 있으며, 충분한 수분과 온도의 조건에서도 발아가 관찰되지 않아 형태 · 생리적 휴면으로 판단되었다. 종자는 BAP 처리에서 휴면이 타파되는 것을 확인하였으며, 특히 BAP 농도에 따른 발아율은 통계적으로 유의한 값을 가졌다 (F=23.208, P<0.01). 건조된 종자에 비해 BAP 처리된 종자는 발아 2단계에서 몇가지 단백질의 증가가 관찰되었다. 대부분의 종자는 30S ribosomal protein subunit으로, 휴면상태에서 발아상태로 변환이 일루어지는 생리적 변화의 증거로 확인된다. 특히 발아2단계를 지나는 세뿔투구꽃 종자에서는 cytochrome subunit과 photosystem II protein의 급격한 증가가 관찰되었는데, 이는 배아의 발달 결과인 자엽이 발아 즉시 광합성이 가능하도록 준비하는 과정에서 발현 된 것으로 추정한다. 본 연구는 발아2단계에서 휴면타파에 직접적인 영향을 미치는 요인을 발견하지 못하였으나, 휴면타파에 중요한 단계인 발아 2단계 종자의 생리학적 변화를 이해하기 위한 기초자료로 활용 될 수 있을 것이다.

• 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.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.05a
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• pp.144-144
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• 2002

• The Korean Journal of Ecology
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• v.25 no.2
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• pp.93-100
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• 2002

In order to analyze the life cycle of A. artemisiifolia var. elation 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℃ ∼ 32℃. Optimum temperature for germination was 24℃. 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℃, 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℃ with the 1.34% germination. An induced dormancy occurred at 12℃ making the 5.34% fecal 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.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.24-30
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• 1985

The effect of some organic solvents on interrupting diapause of Bombyx mori eggs was examined to provide a clue to the mechanism of diapause initiation. Methyl alcohol and benzene proved to be efficient in developing the prospective diapause eggs upto the stage of hatching or body pigmentation of the embryos. On the other hand, most of the eggs soaked in chloroform and mixture solution of chloroform-methyl alcohol (2:1) died in the early embryonic developmental stage with yellow or red brown colours, and the egg weights decreased upto ca. 40% of the original weight 8 days after the treatments. Methyl alcohol treatment for 2, 5 and 10 min to the 5hr-old-eggs led to empergence of the larvae, with high incidence (70∼80%) in the race of Kumchu X Chonghwa and with low indidence (1∼4%) in Daezo. The effect of same treatment to 20hr old eggs decreased to ca. 10% in the emergence of larvae in Kumchn X Chonghwa and increased to 20∼30% in Daezo, while the effect disappeared shortly after the diapause initiation (48hr-old-eggs). Considering the high dependency upon the egg age of the sensitivity to solvents, it was supposed that initiation and termination of diapause may be controlled by different mechanism. It was also suspected that the solvents exert their effect on the permeability of the eggshell.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.193-207
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• 1993

The seed dormancy of weed species is the important mechanisms to unfavorable conditions but it brings about critical problems in weed control. The factors which induced dormancy were varied with species and their physiological conditions. More than 20 of 50 species of dominant weed species showed the seed dormancy. When several physical treatments were given to seeds to break the dormancy, each species showed the different responses. The germination percentage and germination velocity were increased with alternating temperature. The treatment of more than 4 weeks of stratification had strong effect on dormancy breaking. The ${\alpha}-amylase$ activities of germinating seeds were increased in proportional to the period of stratification treatment of dormant seeds. The contents of soluble protein and soluble sugar were changed slightly with stratification.