• 한국산림과학회지
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• 제71권1호
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• pp.55-58
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• 1985

현사시나무에 흔히 분포(分布)하는 부정아유래조직(不定芽由來組織)과 dimple 및 그 주변조직(周邊組織)의 특징(特徵)을 조사(調査)한 결과(結果)는 다음과 같다. 부정아유래조직(不定芽由來組織)은 도관(導管)이 거의 발달(發達)하지 않으며 구성세포(構成細胞)의 직경(直徑)이 작고 벽후(壁厚)가 두껍다. 주변조직(周邊組織)은 목섬유(木纖維)가 만곡(彎曲)하고 격벽세포(隔壁細胞)를 형성(形成)하는 경우가 많으며 방사방향(放射方向)으로 급격(急激)히 만곡(彎曲)하고 방사조직(放射組織)이 다열화(多列化)한다. 또 부정아유래조직(不定芽由來組織) 및 dimple에 인접(隣接)한 선상변색부(線狀變色部)의 도관(導管)에는 상해(傷害) 타일로시스가 발달(發達)한다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.213-237
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• 1987

In vitro flowering system may minimize the confounded influence of non-floral meristem parts of plants in studying the relationship of a given treatment and flowering responses. We have induced flower buds from plantlets regenerated from zygotic embryo-derived somatic embryos of ginseng, which circumvented the normal 2-year juvenile period before flowering. The result suggests that the adulthood of ginseng root explants in the experiment previously conducted by Chang and Hsing (1980; Nature 284: 341-342) is not prerequired to flowering of plantlets regenerated through somatic embryogenesis. We have also induced flower buds from elongated axillary brandches from cotyledonary nodes by culturing ginseng zygotic embryos, seedlings, and excised cotyledonary nodes. It was found that 6-benzyladenine (BA) supplemented to the medium was essential for flowering, whereas abscisic acid (ABA) was inhibitory. Gibberellic acid(GA3) was also required for flowering when ABA was present with BA in the medium. The results suggest that cytokinins, gibberellins, and inhibitors play primary, permissive, and preventive roles, respective-ly, in the induction of flowering of ginseng. Tran Thanh Van (1980; Int. Rev. Cytol., Suppl. IIA: 175-194) has developed the "thin cell layer system" in which the induction of shoots, roots, or flower buds from epidermal layer explants were controlled by culture conditions and exogenous growth regulators in the medium, Utilizing the thin cell layer system, Meeks-Wagner et al. (1989; The Plant Cell 1: 25-35) have cloned genes specifically expressed during floral evocation. However, the system is too tedious for obtaining a sufficient amount of plant materials for biochmical and molecular biological studies of flowering. We have developed a garlic callus culture system and one obvious advantaging over the thin cell layer system is that an abundant cells committed to develope into flower buds proliferate. When the above cells were compared by two-dimensional gel electrophoresis with those which have just lost the competence for developing into flower buds, a few putative proteins specific to floral evocation were detected. The garlic callus culture system can be further explored for elucidation of the molecular biological mechanism of floral evocation and morphogenesis.hogenesis.

• 한국자원식물학회지
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• 제28권6호
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• pp.697-703
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• 2015

Twenty apple germplasm accessions from the Korean Genebank were successfully cryopreserved using two-step freezing to back up genetic resources maintained by field collections. This study examined the morphological and genetic stability of cryopreserved dormant apple buds that were stored in liquid nitrogen, and then rewarmed and regrown. Whole plants were regenerated directly from dormant buds through budding without an intermediary callus phase. The cryopreserved buds produced high levels of shoot formation (76.2-100%), similar to those of noncryopreserved buds (91.3-100%), with no observed differences between cryopreserved and noncryopreserved materials. Three of the twenty cryopreserved apple germplasm accessions were used to assess morphological and genetic stability. No differences in morphological characteristics including shoot length, leaf shape, leaf width/length ratio, and root length were observed between controls (fresh control and noncryopreserved) and cryopreserved plantlets. The genetic stability of regenerants (before and after cryopreservation) was investigated using inter simple sequence repeat (ISSR) markers. The ISSR markers produced 253 bands using four primers, ISSR 810, SSR 835, ISSR 864, and ISSR 899. These markers showed monomorphic banding patterns and revealed no polymorphism between the mother plant and regenerants before and after cryopreservation, suggesting that cryopreservation using two-step freezing does not affect the genetic stability of apple germplasm. These results show that two-step freezing cryopreservation is a practical method for long-term storage of apple germplasms.

• Plant Biotechnology Reports
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• 제2권1호
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• pp.7-11
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• 2008

A simple, high-frequency and reproducible protocol for induction of adventitious shoot buds and plant regeneration from leaf-disc cultures of Jatropha curcas L. has been developed. Adventitious shoot buds were induced from very young leaf explants of in vitro germinated seedlings as well as mature field-grown plants cultured on Murashige and Skoog's (MS) medium supplemented with thidiazuron (TDZ) ($2.27{\mu}M$), 6-benzylaminopurine (BA) ($2.22{\mu}M$) and indole-3-butyric acid (IBA) ($0.49{\mu}M$). The presence of TDZ in the induction medium has greater influence on the induction of adventitious shoot buds, whereas BA in the absence of TDZ promoted callus induction rather than shoot buds. Induced shoot buds were multiplied and elongated into shoots following transfer to the MS medium supplemented with BA ($4.44{\mu}M$), kinetin (Kn) ($2.33{\mu}M$), indole-3-acetic acid (IAA) ($1.43{\mu}M$), and gibberellic acid ($GA_3$) ($0.72{\mu}M$). Well-developed shoots were rooted on MS medium supplemented with IBA ($0.5{\mu}M$) after 30 days. Regenerated plants after 2 months of acclimatization were successfully transferred to the field without visible morphological variation. This protocol might find use in mass production of true-to-type plants and in production of transgenic plants through Agrobacterium/biolistic-mediated transformation.

• 농업생명과학연구
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• 제44권6호
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• pp.39-44
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• 2010

An efficient method for the rapid propagation of Smilax china from axillary buds was established. Plants with thick leafage were selected from Korea native S. china population. Axillary buds of S. china collected from selected plant and were cultured in various culture media (2MS, MS, 1/2MS, WPM, B5 and SH medium). Shoot was induced from axillary bud on MS basal medium after 4 weeks of culture. 1/2MS medium showed a higher growth rate than those of the others, while the lowest shoot growth was obtained in 2MS medium. Among the sucrose concentrations, 5% sucrose was the optimum level for shoots growth from axillay buds. Among cytokinins, $0.5mgL^{-1}$ 6-benzylaminopurine (BAP) treatment showed the best performance on shoot multiplication, yielding average shoot multiplication forming about 2.4. Rooting was induced directly near the base of the shoot on 1/2MS medium containing with three-auxins ${\alpha}-napthalene$ acetic acid (NAA), indole acetic acid (IAA) and ${\beta}-indolebutyric$ acid (IBA) (0.5 and $1.0mgL^{-1}$). The $1.0mgL^{-1}$ IBA treatments induced earliest rooting with maximum of root number and root growth. These rooted plantlets were successfully transferred to pots for 4 weeks hardening process, and were transferred to soil with above 90% survival rate.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.15-15
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• 2019

The walnut (Juglans regia L.), a member of the Juglandaceae, is native to the mountain ranges of central Asia. This species of walnut is valued commercially for its nuts and in some areas for its timber. The seeds of walnut are recalcitrant and it has strong integument dormancy and their germination is irregular, making its natural propagation difficult. Low percentage of seed germination and long propagation cycle are the main problems of propagation. This study was conducted medium composition on in vitro plantlet regeneration from axillary buds of walnut. It has proved to be the most generally applicable and reliable method of in vitro propagation. Micropropagation culture that axillary buds are excised aseptically enables faster multiplication of plants. The axillary buds of walnut new cultivar "Sinlyeong" were cultured on two basal media which contained the different plant growth regulators depending on the respective shooting and rooting stage. After 12 weeks, the shoot generation rate was 85.3%, the shoot number and its length were 1.9/explant and 2.7 cm in the most favorable medium composition. The percentage of rooting was 25.4%. From these results, it was found the optimum basal medium and plant growth regulator for in vitro plant regeneration from axillary buds of walnut new cultivar "Sinlyeong". However, we have continued to search the other medium additives to enhance the rate of walnut root.

• 한국환경농학회지
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• 제40권2호
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• pp.73-82
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• 2021

BACKGROUND: The successful management of jujube trees depends on maintaining a balance between reproductive and vegetative growth. In general, heading cuts of trunk stimulate rather vegetative growth, but could decrease flower initiation. This study was conducted to establish a heading-back pruning severities at planting in the one year old 'Daeneung' jujube whip nursery tree by investigating vegetative growth and fruit yield. METHODS AND RESULTS: The heading back pruning severity was assigned as 5 different ranges as follow: one bud (TR-10, heading back pruning was 10 cm above the ground), three buds (TR-30), five buds (TR-50), seven buds (TR-70), and nine buds (TR-90) were left of scion. The number of buds on whip trunk was correlated to the central leader length and increment of trunk cross-sectional area, negatively, and to the tree height and canopy volume, positively. The yields in the TR-50 treatment were higher about 2 times than other treatments. The fruit diameter was not significantly different among the treatments. CONCLUSION: These results indicated that the optimum location of heading-back pruning in one year old 'Daeneung' jujube tree was 50 cm above the ground as evaluated by the balance of reproductive and vegetative growth.

• 원예과학기술지
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• 제33권2호
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• pp.202-209
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• 2015

본 연구는 수삽을 이용한 'Campbell Early' 포도나무의 발아 특성 관찰을 통해 눈의 내재 휴면 타파를 위한 저온축적과의 관계를 구명하고, 저온에 노출되는 동안 눈의 발달 양상을 관찰하여 발아와 휴면에 대한 기초자료를 마련하고자 하였다. 만개 120일 후(낙엽기 : 10월 7일)부터 시료를 수집하여 수삽하였으며, 만개 후 125일부터 온도가 $7.2^{\circ}C$도 이하로 내려가 CU 축적이 시작되었다. 발아율은 만개 150일 이후부터 100% 발아하였으나 165일 이후 수집된 가지에 비해 최초 발아까지의 기간이 2배 이상 소요되어 발아속도가 현저히 떨어졌다. 즉, 만개 165일 이후에는 100% 발아할 뿐만 아니라 발아 소요일수가 짧아 내재 휴면이 완전히 타파된 것으로 판단되었다. 이 기간 동안 CH 모델과 Utah 모델에 의한 저온 적산 값 계산 시, 각각 321h와 442CU로 조사되었다. 또한 이 시기 이후부터 주아의 생존율이 급격히 감소하였고, 제 1 부아의 생존율은 시기적인 차이 없이 90% 수준으로 높게 유지되었다. 화아형성이 이루어진 눈을 대상으로 조사된 주아 대비 부아의 비율은 내재 휴면이 타파되기 이전인 만개 후 150일에는 1:0.23으로 주아의 비율이 월등히 높았으나, 내재 휴면이 타파된 이후 최종적으로 만개후 255일에 이르러서는 1:1.54로 주아에 비해 부아의 비율이 높게 나타났다. 액아의 생존율 및 화아형성율과의 각 조사항목 간 상관분석에서는 주아에서만 상관관계가 인정되어 주아의 생존율 자체는 시기와 가장 밀접한 관련을 나타내었고, 주아의 생존율과 화아형성률 사이에 높은 정의 상관관계가 나타났다.

• Journal of Applied Biological Chemistry
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• 제55권3호
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• pp.195-198
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• 2012

Four chromone derivatives (1-4) were isolated from the clove buds (Syzygium aromaticum). Of these, two chromone C-glucosides (1 and 2) showed significant PEP inhibition with $IC_{50}$ values of $1.48{\pm}0.02$ and $1.74{\pm}0.03{\mu}M$ and $K_i$ values of $0.27{\pm}0.02$ and $0.50{\pm}0.05{\mu}M$, respectively. They also exhibited strong antioxidant capacities against the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt radical system with $EC_{50}$ values of $4.13{\pm}0.04$ and $4.79{\pm}0.03{\mu}M$, respectively.

• Journal of Plant Biology
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• 제26권1호
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• pp.33-39
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• 1983

Twigs bearing floral buds of Rhododendron yedoense var. poukhanense(Ryp) and R. sinmsii(Rs), hardy species in Korea, were used to investigate the cold hardiness in relation to the developmental and anatomical characteristics, and the changes of water content. In floral buds of both species, the reproductive organs, pistils and stamens, matured within the bud scales in early ctober to prepare for a cold acclimation. The ray parenchymatous areas occupied in xylem were 41% in Ryp and 38% Rs. As the storage temperature is raised from 2 to 17$^{\circ}C$, water content increased more highly in Rs than in Ryp. Exotherm temperature of floral bud in Ryp was generally lower than that in Rs. The result supports that the higher cold-hardiness is achieved owing to the earlier maturation of floral buds, to the larger area of ray parenchyma in xylem, and to the lesser increase of water content as the storage temperature is raised.