• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.349-353
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• 2004

Mature embryo and leaf base segment of Korean oat were used as materials in an experiment to check plant regeneration efficiency. MS media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin, and picloram were used for callus induction from mature embryos and leaf base segments. Three mg/l of 2,4­D and 3 mg/l of picloram in callus induction medium showed high frequency for plant regeneration from mature embryos. Leaf base segments were transferred to callus induction medium and incubated at $25^{\circ}C$ in 16/8 hr light/dark cycle for 3 weeks. Callus induction from leaf base segments of Malgwiri showed high efficiency in medium containing 3 mg/l of 2,4-D and 1 mg/l of kinetin $(91.8\%)$. In case of Samhangwiri, the combinations of phytohormones did not show significant difference. Regeneration from leaf base segments showed high frequency in shoot medium containing 1 mg/l of antiauxin, tri-iodobenzoic acid (TIBA) and 1 mg/l of 6-benzyladenine (BA). Calli induced from leaf base segments of Samhangwiri and Malgwiri in media containing 3 mg/l of 2,4-D and 3 mg/l of picloram showed high regeneration frequency. It appears that the callus initiation medium may be an important factor for subsequent plant regeneration.

• Korean Journal of Medicinal Crop Science
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• v.17 no.5
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• pp.328-334
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• 2009

Experimental purpose was to evaluate growth characteristic and abscisic acid (ABA) responses against salt/drought stresses. In the shoot biomass, creeping thyme was tolerated in mild NaCl stress, ranging 0 to 100 mM, while it was severely reduced in higher salinity. Under constant drought stress, the shoot biomass of creeping thyme showed a worse value compared to that of 100 mM NaCl treatment. Chlorophyll degradation was more severe in immature leaf than mature leaf under salt and drought stresses. In salt stress, immature leaf produced much amounts of ABA compared to mature leaf and also immature leaf showed faster increase of ABA than that of mature leaf. In drought stress, immature leaf responded to stress within 24 hours by the increase of ABA, while mature leaf responded to at 72 hours. Our results recommended that the optimal salinity level of creeping thyme was 50~100 mM NaCl.

• Korean Journal of Medicinal Crop Science
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• v.14 no.2
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• pp.92-95
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• 2006

A method for plant regeneration via organogenesis from Pelagonium inquinans leaf disc has been developed. Mature leaf explants were collected from field-grown plants and used for the induction of adventitious shoot regeneration on Murashige and Skoog (MS) medium supplemented with 3% (w/v) sucrose plus plant growth regulators. Maximum shoot organogenesis, with $11.8{\pm}1.5$ shoots (98.6%) per leaf disc, was obtained with $2\;mg/l$ $N^6-benzyladenine$ (BA) and $0.5\;mg/l$ ${\alpha}-naphthyleneacetic$ acid (NAA) in 30 days. For rooting, the in vitro proliferated and elongated shoots were excised into 1.5-2 cm in length microcutting, which were plated individually on an half-strength MS (1/2MS) medium supplemented with 2% (w/v) sucrose plus various concentrations of indole-3-butyric acid (IBA). Shoots rooted with a frequency of 100% following culture on 1/2MS medium containing $0.5\;mg/l$ IBA.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.33-33
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• 2003

Most of leaf teas, except flower tea, were considered as good materials with basic conditions for tea manufacture because water content was below 6 %, Crude protein was the greatest component in roasted young leaf tea, crude fats in roasted mature leaf tea and ashes in fermented young leaf tea. Caffein were present as the highest amount(5.18%) in steamed mature leaf tea, showing less amount than greenp teas. Catechin were contained as the highest amount in all kinds of teas, especially fermented young leaf tea. was the highest(9.57%). Tannin, which highly related with tea quality including astringent taste, color and perfume, were present as the highest amount in fermented young leaf tea.(중략)

• Korean Journal of Medicinal Crop Science
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• v.19 no.5
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• pp.313-318
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• 2011

This study was carried out to utilize the byproducts (flower, immature and mature berry, leaf and stem) of ginseng. Yield of byproducts were $32.7{\pm}9.8g$ in flower, $68.2{\pm}2.2g$ in immature berry, $48.5{\pm}4.3g$ in mature berry, $316.2{\pm}20.5g$ in leaf, and $296.6{\pm}15.4g$ in stem per $3.3m^2$ ($180{\times}90cm$, ginseng root $675.5{\pm}35.7g$/drybasis. The total saponin contents of ginseng byproducts and root are $52.36{\pm}1.24$, $68.71{\pm}1.98$, $168.89{\pm}0.57$, $68.26{\pm}1.32$, $7.85{\pm}0.61$ and $35.08{\pm}0.96$ mg/g, respectively. The main ginsenoside of all byproducts was Re and the highest content was $132.23{\pm}1.56$ mg/g in mature berry. But flower and berry was not detected Rf and Rh1, respectively. Total polyphenolic compound content on mature berry was the highest, $2.242{\pm}0.140%$, after, immature berry > leaf > flower > root > stem order. The DPPH radical scavenging activity on mature berry was the highest, $0.115{\pm}0.004$ mg/mL($IC_{50}$), and the others were the same order of polyphenolic compound and ginsenoside content on byproducts.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.309-315
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• 1999

Rice seedling test was conducted to check the loging tolerance at ripening stage through evaluating the root characters. Thirteen Korean and foreign rice cultivars with direct seeding adaptable or high quality characteristics were grown in a cell pot and under submerged paddy. The root characters and pushing resistance of rice hill were determined at seedling and ripening stage, respectively. The diameter of crown root at the 7th and 8th leaf stages was thicker in lodging tolerance cultivars than those of others and showed significant-positive correlation with both pushing resistance and crown root diameter of mature plants. Also, the tensile strength of crown root at the 7th and 8th leaf stage showed highly positive correlation with the tensile strength of crown root of mature plants. The number of crown root at 7th leaf stage was significant-positively correlated with that of mature plant. The diameter of seminal root was not significantly correlated with the diameter of crown root throughout the whole growth stage. These results indicate that the diameter, tensile strength and number of crown root associated with root lodging tolerance can be detected with the seedling at about 7th or 8th leaf stage, and the seedling test using the cell pot is an useful and practical method to select lodging tolerant cultivars or lines of rice based on root characters, especially diameter of crown root.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.236-243
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• 2009

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed throughout China, Mongolia and Siberia. This study was conducted to investigate an optimal condition for plant regeneration from mature seeds, leaf base segments, and root segments in L. chinensis. Plant growth regulators affecting embryogenic callus induction and plant regeneration were investigated by four-factor-three-level [L9 (34)] orthogonal test in this study. The effects of explants types (mature seeds, leaf base segments and root segments), callus types, medium types were examined in this study. Wild type (WT) and Jisheng No. 1 plants (JS) were used for primary callus induction. A clear explants difference was seen during callus induction; mature seeds were considered as the preferred explants; and the highest frequency of callus induction was obtained in Medium 6 using mature seeds as explants in WT. Plant regeneration ability was evaluated by frequencies of green callus forming, shooting, rooting, and shooting with roots. Effect of α-naphthalene acetic acid (NAA) on shoot regeneration was remarkable with the highest frequency of 70.8% in WT after 2-month culture. The medium with 0.2- 0.5 mg/L NAA was found to have the highest shoot induction. All regenerated shoots were successfully rooted when transferred on half-strength Murashige and Skoog (MS) basal medium. The acclimatized plantlets were grown to mature with flowering and seeds setting in green house conditions.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.314-322
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• 2004

This research has been undertaken to increase availiability of native Camellia japonica leaf and flower in Korea as a edible-medicinal resource. Chemical compositions, antioxidant and antimicrobial activities in different parts of camellia were investigated. Crude protein contained the highest in young leaves(14.22%) but less than 10% in different parts. The contents of crude fat and crude ash were 60.48% in seeds and 5.16% in mature leaves, respectively. Methanol extract of young leaf, flower, and flower bud in camellia showed strong antioxidant activity compared with different parts. Also, antioxidant activity of these was higher than that of BHT, but weaker than that of VtC. Antioxidant activity of various parts in camellia were in order of young leaf ＆gt; flower bud ＆gt; flower ＆gt; mature leaf ＆gt; stem ＆gt; bark. Extracts of mature leaf and bark had a remarkable antibacterial activity(0 CFU/$m\ell$) on Bacillus subtilis. The young leaf extract displayed effective growth inhibition against B. subtilis, Candida albicans, and Trichosporon beigelii.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.57-61
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• 2009

The invasive pest Brontispa longissima(Coleoptera: Chrysomelidae), native to Indonesia and Papua New Guinea, has extended its distribution to Australia, Asia and Pacific islands and caused serious leaf damages of the coconut palm Cocos nuciferain the invaded regions. Although biological control using parasitic wasps has successfully reduced population density and leaf damage levels, this pest and its natural enemies have not been efficiently producedin conventional methods using young leaves of C. nucifera. In the present study, we examined suitability of plants easily available in Thailand and Japan for mass rearing of this pest to develop effective mass rearing system of this pest. Mature, green leaves of the palms were also suitable for immature development and adult reproduction of this pest. Since mature leaves of C. nucifera are more abundant and less contaminated with fungus than the unopened leaf buds, mature leaves could be a promising plant diet for mass rearing of B. longissima. Ornamental palms such as Hyophorbe lagenicaulis and Washingtonia filifera were also suitable for immature development and reproduction of B. longissima. Away from palms, the cattail Typha spp. can sustain immature development and adult reproduction of B. longissima. In the area where C. nucifera is rare or not available, W. filifera or Typha spp. would be good food plants for mass rearing of this pest.

• Journal of Plant Biology
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• v.28 no.4
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• pp.285-296
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• 1985

To examine the differentiation and transition of vascular system in Prunus davidiana FR., the mature embyro and developing seedlings were embedded in paraplast and treated by clearing method. In mature embryo, the procambium was connected with the epicotyl-hypocotyl-radicle axis and cotyledons, whereas protophloem and protoxylem were restricted primarily to the mid-vein and two lateral veins of the cotyledonary base. With the onset of germination, protophloem and protoxylem were differentiated both acropetally and basipetally from the cotyledonary base. The first and second leaf traces appeared in the cotyledonary node, and then differentiated bidirectionally toward the epicotyl and the root tip. The 3rd to 6th leaf traces were connected with the cotyledonary traces in hypocotyl. At the part of the root tip, the xylem was a diarch. As the first and second leaf traces were superimposed at the middle part of the root, the diarch xylem was changed to a tetrarch. As the cotyledonary traces were diverged below the root base, the tetrarch xylem was changed to an octarch. It was suggested that the vascular system of the epicotyl might be superimposed on that of the cotyledon-hypocotyl-root during the formation of the primary vascular system of Prunus davidiana.