• Journal of Ecology and Environment
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• 제45권4호
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• pp.174-181
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• 2021

Background: Euphorbia jolkinii Boiss. is a perennial species native to Jeju Island and the southern coastal area of Korea. Particularly on Jeju Island, the yellow flowers of E. jolkinii Boiss. have a high ornamental value because of their contrast with basalt. This study was conducted to investigate the effects of different temperatures (5, 15, 20, and 25 ℃) and gibberellic acid (GA₃) concentrations (0, 10, 100, or 1000 mg/L) on seed dormancy and germination of E. jolkinii. In addition, we classified the seed dormancy type and compared types with those of other species in the same genus. Results: The number of seeds with viable embryos and endosperms was approximately 66%. The final germination percentages at 5, 15, 20, and 25 ℃ were 51.7%, 83.5%, 2.6%, and 0.0%, respectively. In GA₃ concentration experiments, the final germination percentages of 0, 10, 100, and 1000 mg/L were 83.5%, 91.7%, 79.1%, and 83.4%, respectively, at 15 ℃ conditions, and 0.0%, 6.9%, 13.2%, and 27.3%, respectively, at 25 ℃. Conclusions: Germination improved at temperatures of 15 ℃ or lower. Furthermore, GA₃ treatment effectively reduced germination times. Thus, the seeds of E. jolkinni were classified as having non-deep physiological dormancy.

• Journal of Ginseng Research
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• 제31권1호
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• pp.14-22
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• 2007

As the zygotic embryo of North American ginseng (Panax quinquefolius L.) matured during stratification over 203 days it grew from 0.75 to 5.2 mm. Embryo excision and culturing on media containing different concentrations of two growth regulators, gibberellic acid ($GA_3$, 1 to 10 ${\mu}M$) and benzyladenine (BA, 1 to 5 ${\mu}M$), during stratification, showed that shoot and root number and the shoot, root and cotyledon length increased with increased stratification time. Gibberellic acid was the more effective growth regulator for increasing shoot and root number and shoot, root and cotyledon lengths. Immature embryos (stratified for up to 63 days) needed growth regulators for further development. Cultures on $GA_3$ at the last culture date (stratified for 203 days) when embryos were mature, produced multiple shoots but there was no effect of $GA_3$ concentration. Benzyladenine inhibited shoot and root growth regardless of embryo stratification. Growth regulators had little effect on cotyledon length of mature embryos. Embryos cultured on $GA_3$ combined with BA were green on all culture dates whereas greening in the control and BA treatments increased with culture date. The BA treatments induced 100% swelling of the embryos on the final culture date while in the control and $GA_3$ treatments there was no swelling. There was little or no curling in the control and BA treatments and a linear decrease in curling with culture date in the $GA_3$ and $GA_3$ + BA treatments.

• 한국자원식물학회지
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• 제34권1호
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• pp.59-63
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• 2021

2% 알진산으로 캡슐화하여 만든 사과 인공종자의 발아 연구를 위하여 자엽을 부분적으로 제거한 후 영양분과 지베렐린을 단독 또는 조합처리한 알진산으로 캡슐화하여 발아율을 측정하였다. 3/4자엽 배(3/4 CE), 1/2자엽 배(1/2 CE), 1/4자엽 배(1/4 CE), 그리고 자엽을 완전히 제거한 배(NCE)로 만든 인공종자는 정상배로 만든 인공종자의 발아율 82.31%에 비하여 최대 24.44%까지 감소하였으며, 그 감소한 발아율은 MS영양분과 지베렐린 처리에 의해 상당히 회복되었다. 특히, 알진산 단독에서 1/2 자엽을 갖는 인공종자의 낮아진 발아율(55.81%)은 3% sucrose와 80 mg/L 지베렐린 조합처리에 의해 98.74%까지 증가하였다. 자엽이 없는 인공종자의 경우 낮아진 발아율(24.44%)은 MS용액과 80 mg/L 지베렐린 조합처리에서 82.45%까지 회복되었다. 이러한 결과는 배의 발아율이 자엽의 부분적 제거에 의해 억제되었고, 그 감소된 발아율은 영양분과 지베렐린 처리에 의해 상당히 회복될 수 있음을 보여 주었다.

• 한국토양비료학회지
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• 제47권6호
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• pp.480-485
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• 2014

In satsuma mandarin (C. unshiu Marc. cv. Miyagawa), alternate bearing is frequently occurred. It is very difficult to control and maintain the optimum production because satsuma mandarin is a very sensitive citrus cultivar. We carried out the experiment to find out the effects of foliar application of gibberellic acid ($GA_3$) and machine oil emulsion mixture on flowering and fruit quality of satsuma mandarin grown on open field. The treatments were composed of control (no application), $GA_3$ (25, 50 and $100mg{\cdot}L^{-1}$), machine oil emulsion 100 times and mixture of $GA_3$ (25 and $50mg{\cdot}L^{-1}$) with machine oil emulsion 100 times on 16 year-old 'Miyagawa' satsuma mandarin on December 30, 2012. Foliar application of $GA_3$ during winter season led to a reduction of the flowering in the following year. $GA_3$ decreased flowering in dose dependant manner. However, application of $GA_3$ and machine oil emulsion (100 times-diluted mixture) inhibited effectively the flowering compared to $GA_3$ only. Also, flower-leaf ratio was significantly decreased by the application of $GA_3$ 25 (0.54) and $50(0.41)mg{\cdot}L^{-1}$ with machine oil emulsion mixture in comparison to $GA_3$ 25 (0.86) and $50(0.60)mg{\cdot}L^{-1}$ only. The number of leaves per fruit increased in application of $GA_3$ and machine oil emulsion mixture as concentration of $GA_3$ increased. Fruit weight and sugar-acid ratio also increased in comparison to the control whereas fruit size, soluble solid content and acidity remained unchanged. From the results, it was suggested that $GA_3$ application can reduce the number of flowers on the alternate bearing of satsuma mandarin. Moreover, application of $GA_3$ (25 and $50mg{\cdot}L^{-1}$) with machine oil emulsion 100 times mixture can reduce the flowering effectively without altering fruit maturity and soluble solid contents. Therefore, it can be concluded that the application of $GA_3$ 25 and $50mg{\cdot}L^{-1}$ with machine oil emulsion 100 times might be useful in controlling alternate bearing in satsuma mandarin.

• 한국작물학회지
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• 제38권4호
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• pp.360-365
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• 1993

벼 기계이앙 어린모 육묘시 생장조절제가 묘의 초장신장 촉진에 미치는 효과를 구명하기 위하여 화성벼를 공시하고 6가지의 생장조절제를 사용하여 종자침종 효과와 6가지의 생장조절제를 사용하여 종자침종 효과와 묘 생장을 조사하여 다음과 같은 결과를 얻었다. 1. Gibberellin과 Metalaxyl은 어린모의 초장신장을 촉진시켰으며, Tetracycle은 초장을 억제하였다. 2. Gibberellin의 엽면분무처리가 종자침종처리보다 어린모의 초장신장에 더 효과적이었다. 3. 어린모의 초장신장 촉진을 위한 Gibberellin의 엽면분무처리의 적정농도는 약 10ppm이었다. 4. Gibberellin의 엽면분무의 적정처리시기는 파종후 3～4일 이었다.

• 원예과학기술지
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• 제33권3호
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• pp.331-339
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• 2015

This research was performed to determine the temperature requirements for embryo growth and radicle emergence of Hepatica asiatica Nakai, a perennial herb native to Korea. Seed viability, embryo growth, and radicle emergence were monitored in seeds exposed to various temperatures (10, 15, $20^{\circ}C$ and $30{\rightarrow}15^{\circ}C$). Laboratory experiments at various temperatures revealed that (1) embryo elongation occurred effectively between 10 and $15^{\circ}C$; (2) radicle emergence occurred only at $15^{\circ}C$; (3) a warm stratification (2-8 weeks at $30^{\circ}C$) was not required for embryo elongation and radicle emergence, and led to inhibition of radicle emergence; (4) application of gibberellic acid ($GA_3$) promoted embryo growth, but not radicle emergence. These results suggested that H. asiatica seeds have two separate mechanisms to overcome dormancy, either by $GA_3$ (morphological dormancy) or temperature (physiological dormancy), and warm stratification is not involved in breaking radicle dormancy. These findings indicate that H. asiatica seeds have morphophysiological dormancy.

• Journal of Plant Biotechnology
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• 제47권1호
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• pp.53-65
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• 2020

Here, we describe an efficient and rapid protocol for the micropropagation of Thymus pallidus Cosson ex Batt., a very rare medicinal and aromatic plant in Morocco. After seed germination, we tested the effect of different macronutrients, cytokinins alone or in combination with gibberellic acid (GA₃) or auxins, on T. pallidus plantlet growth. We found that Margara macronutrients (N₃₀K) had the best effect on the in vitro development of the plantlets. The addition of 0.93 μM/L 1,3-diphenylurea (DPU), 0.46 μM/L adenine (Ad), and 0.46 and 0.93 μM/L kinetin (Kin) resulted in the best shoot multiplication and elongation. In addition, the combination of 0.46 μM/L Kin, DPU, or Ad with gibberellic acid, in particular, 0.46 μM/L Ad + 0.58 μM/L GA₃ and 0.46 μM/L Kin + 1.15 μM/L GA₃, led to better bud and shoot multiplication. Moreover, the integration of the combinations of 0.46 μM/L Kin and auxins, namely 0.46 μM/L Kin + 2.85 μM/L indole-3-acetic acid (IAA), 0.46 μM/L Kin + 2.85 or 5.71 μM/L indole-3-butyric acid (IBA), and 0.46 μM/L Kin + 0.3 or 0.57 μM/L 1-naphthaleneacetic acid (NAA), in the culture medium led to better root development and optimized aerial growth. Finally, the in vitro plants from the medium containing N₃₀K + 0.46 μM/L Kin + 2.85 μM/L IAA were successfully acclimatized; these plants served as a source for repeating in vitro culture.

• Journal of Ginseng Research
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• 제10권2호
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• pp.187-192
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• 1986

Activity of endogenous growth regulator in 4th year Panax ginseng root was investigated by second leaf sheath test of rice seedling and paper chromatogram of a acidic fraction of methanol extract before (March 28) and after (May 9) emergence of root bud, at the late season (Sept.4) and after leaf fall (November 11). GA$_3$ and ABA were used as reference. According to paper and high performance liquid chromatography of samples and authentic growth regulators the presence of insole acetic acid (IAA), gibberellic acid (GA$_3$) and abscisic acid (cis and trans ABA) was confirmed. These three regulators appeared to consist of major system though the existence of other regulators could not be ruled out. IAA activity seemed little changed through out the seasons. GA activity decreased in the later stages while ABA activity increased.

• 생물환경조절학회지
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• 제23권2호
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• pp.77-82
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• 2014

개량머루의 과립 크기와 생산량을 증가시키기 위한 $GA_3$와 TDZ 처리의 효과와 적정 처리 농도를 구명하기 위하여 본 실험을 수행하였다. $GA_3$ 처리는 모든 처리구에서 모두 과립 비대 효과를 보였으며 100과 $200mg{\cdot}L^{-1}$ 처리구의 과립이 가장 컸다. 또한 $GA_3$ 처리구는 착립수가 증가하여 과방중이 크게 생산되었으나 당도 및 산도에 전혀 차이가 없었다. $200mg{\cdot}L^{-1}$ 처리구에서 과피 오염 및 탈립과 같은 약해가 발생되었다. $GA_3$와 TDZ 혼용 처리에서는 $GA_3$ 혹은 TDZ의 농도가 높은 처리구의 과립이 크기는 크지만 과실의 성숙이 지연되어 당도가 낮고 산도가 높은 과실이 수확되었다. $GA_3$와 TDZ를 처리했을 때 과피 조직은 세포층수에는 변화 없이 유관속 조직까지의 길이가 증가하였다. 따라서 개량머루의 $GA_3$ 와 TDZ처리는 세포 분열에는 영향 없이 세포 크기가 증가됨으로 인해 과립 크기가 증가하였다. 개량머루는 착립이 결정되는 시기가 짧기 때문에 착립 직후 2~3회에 나누어 처리해야 착립률을 향상시킬 수 있었다. 개량머루의 과립 비대와 착립률을 향상시키기 위해서는 $GA_3$ $100mg{\cdot}L^{-1}$ 이하의 단독 처리 혹은 $GA_3$ 50+TDZ $1.25mg{\cdot}L^{-1}$의 혼용 처리가 적합할 것으로 판단되었고 TDZ 처리에 의해 과실의 성숙이 지연되므로 성숙과를 수확하도록 주의해야 할 것으로 생각된다.

• 한국환경과학회지
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• 제24권6호
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• pp.755-762
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• 2015

The present study was conducted to develop seed treatment for the production of healthy and clean peanut sprout. Dry heat treatment of peanut seeds reduced the incidence of the rot. The seed treatment condition at $52^{\circ}C$ for 10 h. was the most efficient without inhibiting seed viability significantly. Seeds were dark cultured at $27^{\circ}C$ for up to 9 days. The treatment of Indole-B and gibberellic acid influenced germination, T50, fresh, dry weight, hypocotyl length, hypocotyl length diameter, root length, number of lateral root and epicotyl of peanut sprout. There were no differences in the germinability of peanut seeds between gibberellic acid treatment methods but higher fresh weight was observed in the GA3 solution spray after 2 hour water soaking. The general growth and lateral root development of peanut sprouts were suppressed by Indole-B which is used for inhibiting root formation and promoting hypocotyls. The treatment of gibberellic acid promoted hypocotyl elongation, but it did not influence on the growth of hypocotyls and root system.