• Journal of Plant Biotechnology
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• 제4권2호
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• pp.53-58
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these "environmental or abiotic stresses", which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity, In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.n factors.

• 생물환경조절학회지
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• 제15권1호
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• pp.100-106
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• 2006

A hypertonic solution of sorbitol was used to precondition Douglas-fir and Western hemlock plug seedlings to improve desiccation resistance. Seedlings were preconditioned by soaking their root balls in water, -0.75 or -1.50 MPa sorbitol solution for 22 hr, and then exposed to desiccation conditions for 8 days. During the desiccation period, a transpirational water loss was significantly reduced by the sorbitol preconditioning, with its effect positively depending on concentration. This preconditioning-induced reduction in water loss was mainly caused by the decline in needle stomatal conductance. Sorbitol-induced stomatal control was more closely associated with reduction in plant water potential, rather than increase in abscisic acid concentrations. After rehydration of stressed-plants, most of the preconditioned seedlings with sorbitol were survived, while only 35% of Douglas-fir and 28% of Western hemlock seedlings treated with water were alive. The post-growth was significantly greater in the preconditioned seedlings than only water-treated seedlings. These results suggested that the earlier stomatal control with sorbitol-facilitated preconditioning could play a role in improving desiccation resistance of evergreen woody plants at transplanting in the field where water supply is limited or dry conditions are prevailing.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1993년도 추계 학술대회지
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• pp.44-45
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• 1993

• Journal of Ginseng Research
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• 제40권4호
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• pp.409-414
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• 2016

Background: The low survival rate of in vitro regenerated Panax ginseng plantlets after transfer to soil is the main obstacle for their successful micropropagation and molecular breeding. In most cases, young plantlets converted from somatic embryos are transferred to soil. Methods: In vitro thickened taproots, which were produced after prolonged culture of ginseng plantlets, were transferred to soil. Results: Taproot thickening of plantlets occurred near hypocotyl and primary roots. Elevated concentration of sucrose in the medium stimulated the root thickening of plantlets. Senescence of shoots occurred following the prolonged culture of plantlets. Once the leaves of plantlets senesced, the buds on taproots developed a dormant tendency. Gibberellic acid treatment was required for dormancy breaking of the buds. Analysis of endogenous abscisic acid revealed that the content of abscisic acid in taproots with senescent shoots was comparatively higher than that of taproots with green shoots. Thickened taproots were transferred to soil, followed by exposure to gibberellic acid or a cold temperature of $2^{\circ}C$ for 4 mo. Cold treatment of roots at $2^{\circ}C$ for 4 mo resulted in bud sprouting in 84% of roots. Spraying of 100 mg/L gibberellic acid also induced the bud sprouting in 81% roots. Conclusion: Soil transfer of dormant taproots of P. ginseng has advantages since they do not require an acclimatization procedure, humidity control of plants, and photoautotrophic growth, and a high soil survival rate was attained.

• Natural Product Sciences
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• 제23권4호
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• pp.253-257
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• 2017

The phytochemical study for the extract of Nelumbo nucifera (Nymphaceae) seeds has led to the isolation of ten compounds including five simple phenolic compounds, two indole derivatives, a flavonoid glycoside, two abscisic acid derivatives. The interpretation of 1D and 2D NMR and ESI-Q-TOF-MS spectroscopic data revealed the chemical structures of isolates to be p-hydroxybenzoic acid (1), protocatechuic acid (2), (E)-p-coumaric acid (3), (E)-ferulic acid (4), (E)-sinapate-4-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (5), tryptophan (6), 3-indoleacetic acid (7), isoschaftoside (8), dihydrophaseic acid (9), dihydrophaseic acid 3'-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (10). To the best of our knowledge, 1 - 5 and 7 were identified for the first time from N. nucifera seeds, and the presence of dihydrophaseic acid (9) and its glucoside (10) were demonstrated secondly in this plant.

• 원예과학기술지
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• 제29권1호
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• pp.1-9
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• 2011

본 연구는 한지형 마늘인 '의성마늘'을 이용하여 장일과 단일 조건에서 재배하여 마늘의 인경 분화 및 비대에 미치는 식물 생장 물질의 역할에 대해서 조사하였다. 한지형 마늘의 인경 분화기(4월 16)부터 인경 비대기(4월 24일, 5월 18일)에 엽신과 엽초내 식물내생호르몬 abscisic acid (ABA), jamonic acid(JA) 및 당 함량변화는 장일조건에서 ABA 함량이 단일조건에서 ABA 함량보다 높았고, 엽초내 ABA 함량이 엽신내 ABA 함량보다 높은 것으로 조사되었다. 마늘생육시기별 ABA 함량은 인편 분화기에서 인경 비대개시기까지는 큰 변화가 없다가 인경 비대개시기(5월 2일) 이후부터 인경이 비대 되는(5월 18일) 동안 그 함량이 현저히 증가하는 것으로 조사되었다. 반면 단일조건에서는 내생 JA 함량은 변화가 없었으나, 장일조건에서는 인편 분화기(4월 16일)부터 인경 비대개시기(5월 2일)까지 JA 함량은 증가되었다. 엽초내 JA 함량($30.19-53.19ng{\cdot}g^{-1}$ DW)은 엽신내 JA 함량($12.82-20.41ng{\cdot}g^{-1}$ DW)보다 높은 것으로 조사되어 엽초 내 JA 함량에 의해 마늘의 인경 비대가 유도되는 것으로 조사되었다. 장일 조건에서 엽신내 당 함량은 인편 분화기(4월 16일)부터 인경 비대개시기(5월 4일)까지 증가되었고, 인경 비대기(5월 4일에서 5월 8일) 동안 감소하였으나, 엽초내 당 함량은 인편 분화기(4월 16일)부터 인경 비대기(5월 18일)까지 서서히 증가되었다. 결론적으로 한지형 의성마늘 생장양상에 따라 엽초내 호르몬도 변화하는 경향을 보여 호르몬 변화가 마늘 생장과 밀접한 연관이 있음을 보여주었다.

• The Plant Pathology Journal
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• 제36권1호
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• pp.1-10
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• 2020

Since salicylic acid (SA) was discovered as an elicitor of tobacco plants inducing the resistance against Tobacco mosaic virus (TMV) in 1979, increasing reports suggest that SA indeed is a key plant hormone regulating plant immunity. In addition, recent studies indicate that SA can regulate many different responses, such as tolerance to abiotic stress, plant growth and development, and soil microbiome. In this review, we focused on the recent findings on SA's effects on resistance to biotic stresses in different plant-pathogen systems, tolerance to different abiotic stresses in different plants, plant growth and development, and soil microbiome. This allows us to discuss about the safe and practical use of SA as a plant defense activator and growth regulator. Crosstalk of SA with different plant hormones, such as abscisic acid, ethylene, jasmonic acid, and auxin in different stress and developmental conditions were also discussed.

• 환경생물
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• 제27권4호
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• pp.406-413
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• 2009

The enzyme invertase contributes to sugar unloading, pathogen defense, differentiation and development in plants. We cloned the complete cDNA of a soluble acid invertase from pea seedlings (Pisum sativum) via RT-PCR and the rapid amplification of the cDNA end (RACE) technique. The full-length cDNA of the soluble pea invertase comprised 2237 bp and contained a complete open reading frame encoding 647 amino acids. The deduced amino acid sequence showed high homology to soluble acid invertases from various plants. Northern blot analysis demonstrated the soluble acid invertase gene of P. sativum was strongly expressed in sink organs such as shoot tips and root tips, and induced by abscisic acid, gibberellic acid and jasmonic acid in shoots. Especially, gibberellic acid enhanced the gene expression of the soluble acid invertase in a time-dependent manner. This study presents that the gene expression patterns of a soluble acid invertase from pea are strongly consistent with the suggestion that individual invertase gene product has different functions in the growing plant.

• 한국식품과학회지
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• 제45권5호
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• pp.557-564
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• 2013

본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 $^1H$- 및 $^{13}C$-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-${\beta}$-D-glucopyranosyl ester (화합물 1), 1-[4-O-${\beta}$-D-glucopyranosyl]phenyl ethanone (piceoside, 화합물 2), ${\beta}$-sitosterol (화합물 3), 그리고 ${\beta}$-sitosteryl 3-O-${\beta}$-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다.

• 생명과학회지
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• 제15권2호
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• pp.298-303
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• 2005

포도 '거봉'의 착색을 조장하기 위해 적절한 ABA의 처리시기와 처리 횟수를 알아보기 위하여 본 실험을 수행한 결과 다음과 같은 결과를 얻었다. PAL 효소의 활성은 변색기 처리구와 변색기 10일 후 처리구에서 활성이 높은 것으로 나타났으며, 변색기 10일후 처리구가 변색기 처리구보다 약간 더 높은 효소 활성을 나타냈다. 안토시아닌 함량은 각 처리구 공히 생육기간 동안 계속 증가하는 경향을 보였고, 모든 ABA 처리구는 무처리구에 비해 훨씬 높은 안토시아닌 함량을 나타내었으며, 변색기 10일후 처리구에서 가장 높은 안토시아닌 함량을 나타내었다. 가용성당 함량에 있어서 과당과 포도당만이 검출되었으며, 처리구간에 함량의 차가 그다지 크지 않았다. 처리 횟수에 있어서 PAL 효소의 활성은 각 처리구 공히 증가하다가 감소하는 경향을 보였으며, 2회 처리구는 변색기 10일후의 2회째 처리 이후에도 급속한 PAL 효소 활성 증가가 이어져 최종수확기에서도 비교적 상당히 높은 효소 활성을 보였다. 변색기와 변색기 10일 후의 2회 처리구에서 안토시아닌 함량 증가가 가장 높아 최종수확기에 가서는 무처리구에 비해 5배 이상, 1회 처리구에 비해서는 2배정도 많았다. 1회 및 2회 ABA 처리구 모두 과당과 포도당 함량 공히 무처리구에 비해 약간 높은 경향을 나타냈지만 그다지 큰 차이는 없었다.