• Journal of Plant Biotechnology
• /
• v.29 no.1
• /
• pp.63-68
• /
• 2002

The possibility for mass production of phytol, inhibitory diterpene against ACAT (Acyl-CoA: Cholesterol acyltransferase) was investigated by using callus culture of lettuce. The callus were induced from lettuce cotyledon explants on MS medium containing 0.5 mg.L$^{-1}$ NAA after 4 week's culture. Adventitious roots were formed from the explants on MS medium containing 0.5 mg.L$^{-1}$ IBA or 1.0 mg.L$^{-1}$ NAA. Adventitious shoots and roots were emerged from the callus when the callus was transferred to MS medium containing auxin alone, or with cytokinin. The plant growth regulators and their concentrations for the organogenesis were 1.0 mg.L$^{-1}$ NAA, 0.1 mg.L$^{-1}$ BA, 0.5 mg.L$^{-1}$ NAA with 0.1 mg.L$^{-1}$ kinetin, or 0.5 g.L$^{-1}$ 2.4-D with 1.0 mg.L$^{-1}$ kinetin. Analyses of chlorophyll contents showed that chlorophyll contents were higher in morphogenic calli than in non-morphogenic calli. However, the chemical analyses of gas chromatography indicated that phytol contents were not proportionate to the chlorophyll contents of callus. The content of phytol was higher in callus than in lettuce cotyledon.ledon.

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.6
• /
• pp.475-478
• /
• 2000

The cytosolic glutathione reductase(GR) gene of chinese cabbage was introduced into Lettuce (Lactuca sativa L.) with particle bombardment method. When cotyledon explants were treated with osmoticum-conditioning medium (0.6 M sorbitol/mannitol) 4 hours prior to and 16 hours after bombardment, it was identified by GUS assay that this condition was the most efficient one for introduction of foreign genes into cotyledon tissue of lettuce with particle bombardment. The stable integration of a GR gene was confirmed by the PCR analysis. 0.3, 0.6, 1.5 kbp PCR fragments of transgenes were obtained by three types of primers designed on the basis of GR sequence. To know whether the expression of the GR gene of pBKs-GR 1 can be stably maintained in the next generation, T$_2$selfing seeds obtained from the transformed mother plants were sowed on MS medium supplemented with 200 mg/L kanamycin sulfate. 70% of seedlings showed resistance to kanamycin.

• Journal of Plant Biotechnology
• /
• v.29 no.4
• /
• pp.241-246
• /
• 2002

Somatic embryos or adventitious buds were formed from the segments of zygotic embryo of Lycium chinense Mill. on Murashige and Skoog (MS) medium supplemented with auxins (2,4-D, NAA, IAA) and / or cytokinins (zeatin, kinetin, BAP). Embryogenic callus formed on MS medium containing 0.5 mg/L 2,4-D and then differentiated into somatic embryos without transfer to hormone free medium. On the other hand, adventitious buds were formed on medium with 0.01 mg/L 2,4-D and 0.5 mg/L zeatin. Among various parts of zygotic embryos, the morphogenic potential was higher in the cotyledonary region, and the most organogenic potential was found in cotyledon followed by radicle, hypocotyl, and whole embryo. Histologically, bipolar structure of the heart-shaped embryos were confirmed and in adventitious buds only shoot apical meristems were found to exist.

• Plant Biotechnology Reports
• /
• v.4 no.1
• /
• pp.53-59
• /
• 2010

A specific deleted version of ARABIDOPSIS RESPONSE REGULATOR1 (ARR1) lacking the signal receiver domain (1.152 amino acids)-coding sequence, referred to as $ARR1{\Delta}DDK$, was amplified using Arabidopsis thaliana cDNA prepared from adult leaves and transferred into the genome of Nicotiana tabacum cv. Samsun under the transcriptional control of a ${\beta}$-estradiol-inducible expression system. The ectopic expression of $ARR1{\Delta}DDK$ affected the morphology of transgenic seedlings and their segments in vitro. In the presence of an inducer, ${\beta}$-estradiol, ectopic expression of $ARR1{\Delta}DDK$ induced only the formation of soft, pseudo-bulbous tissue in the root tip region of intact seedlings, which appeared similar to callus generated on a hypocotyl segment in the presence of 2,4-D and 6-benzyladenine (BA), both at $1\;{\mu}M$. Those callus tissues on the root tip region could not generate shoots unless $1\;{\mu}M$ BA was supplied. In segment culture, ectopic expression of $ARR1{\Delta}DDK$ induced calluslike tissue around the cut-end of cotyledon and hypocotyl segments with occasional shoot formation, suggesting that the expression of $ARR1{\Delta}DDK$ could substitute for the effects of cytokinin on these segments. Additionally, treatment with only ${\beta}$-estradiol induced NtWUS, a WUS ortholog in tobacco, which was detected during the process of callus tissue formation in the root tip region and also in cotyledon or hypocotyl segments. These findings suggest that the NtWUS might be associated in the transdifferentiation process caused by the functional regulation of $ARR1{\Delta}DDK$ in transgenic tobacco seedlings.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.3
• /
• pp.333-337
• /
• 2009

This study was conducted to determine contents and estimated availabilities of trace minerals (Cu, Fe, Mn, Zn) in soybean sprouts depending on culture periods such as 1, 3 and 5 days. The proportional changes of Cu estimated availability in cotyledon were between 57.31 and 98.34%, between 63.69 and 82.56% for Fe, 99.19 and 99.82% for Mn and 48.60 and 94.56% for Zn, respectively, based on dry matter. The estimated availabilities of Cu, Fe, Mn, and Zn in hypocotyl were between 34.63 and 56.0%, 20.74 and 40.33%, 86.5 and 95.88%, and 96.11 and 96.61%, respectively, on dry matter basis.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.2
• /
• pp.119-123
• /
• 1998

In order to investigate the possibility of in vitro mass propagation via somatic embryogenesis from Sicyos angulatus L., effects of plant growth regulators and carbon sources on callus induction and somatic embryogenesis were evaluated. Optimal combinations of plant growth regulator for callus induction from cotyledon and inflorescence explants were 2,4-D 2.0 mg/L + BA 0.1 mg/L and 2,4-D 1.0 mg/L + BA 0.1 mg/L in MS basal medium supplemented with sucrose 30 g/L,, respectively. Somatic embryogenesis was observed from cultured inflorescence explants, but it could not be achieved from leaf or cotyledon explants. The most effective plant growth regulators for somatic embryogenesis from callus was NAA 1.0 mg/L + kinetin 10 mg/L in the half strength of MS basal medium supplemented with 20 g/L sucrose.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.2
• /
• pp.125-129
• /
• 1998

Cucumber (Cucumis sativus L.) plants were regenerated through organogenesis and somatic embryogenesis in cotyledon and hypocotyl cultures. The shoots were efficiently formed on the basal region of cotyledons cultured on MS medium containing 1.0㎎/L zeatin and 0.1㎎/L IAA in all cultivars used. Embryogenic calli were formed on hypocotyl segments cultured on MS medium containing 1.0㎎/L 2,4-D in cv. group 'Nakhab' and maintained by consecutive subculture on the same medium every 2-3 weeks without loss of embryogenic ability. Upon transfer to MS basal medium, high frequency somatic embryogenesis was achieved easily from embryogenic callus. Regenerated plantlets through organogenesis and somatic embryogenesis were transplanted to pots and gradually acclimatized to greenhouse condition where they subsequently produced fruits.

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.1
• /
• pp.1-6
• /
• 2000

This study was carried out to find the effects of plant growth regulators on callus formation, rooting and shooting from cotyledon explant in oriental me]on. Various combinations of 0.1 mg/L auxins (IAA, NAA) and 0.5, 1.0. 1.5, 2.0 mg/L cytokinins (BA, kinetin, zeatin) were treated to the MS basal medium, respectively. Callus was induced mort effectively as 2,437.0 mg (FW)/explant in MS medium supplemented with 0.1 mg/L NAA and 2.0 mg/L BA, but that was non-embryogenic callus as colored yellow white and broke easily. Root was induced most effectively at a frequency of 98.0% in MS medium supplemented with 0.1 mg/L NAA and 0-5 mg/L kinetin. Shoots formed on cut part of vein at a frequency of 98.0% in MS medium supplemented with 0.1 mg/L IAA and 2.0 mg/L BA, that were multiple shoots. in case of its concentration, BA and lower concentration of IAA and NAA (0.01 and 0.05 mg/L). respectively. shooting ratio was not increased. The result of treatment with BA 0-5 mg/L and IAA 0.1 mg/L, callus induced at a week, and shoot start to form multiple shoots about 3 weeks after inoculation. After 2 times subculture as 2 weeks intervals, divided shoots rooted and developed into intact plantlets at 10 weeks and then that grown normally on pots after acclimatization.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.6
• /
• pp.311-316
• /
• 1995

In an attempt to obtain intersubgeneric somatic hybrids of Pelargonium aridum and P.zonale, protoplast isolated from the two species were fused by using polyethylene glycol(PEG) and electorfusion methods. Protoplast were isolated from cotyledon and leaf tissues using MS medium containing 550 mM sucrose, 0.7% cellulase (Onozuka R-10) and 0.4% Macerozyme. The optimum number of protoplasts per mL of culture medium was 6 x 10$^4$. Protoplast fused by the electrofusion method were more active than by PEG method. Heterokaryotically fused protoplasts formed calli when cultured in MS medium containing 550 mM glucose, 1 to 2 mg/L NAA and 0.5 to 1 mg/L BA.

• Journal of the Korean Society of Tobacco Science
• /
• v.16 no.2
• /
• pp.102-107
• /
• 1994

This study was conducted to transfer the potato virus Y-necrosis strain resistance from Nicotiana africana to Nicotiana tabacum (cv. NC82) N. africana was crossed with NC82, GErmination of the cotyledon stage, at which time most of the seedling died. However, surviving seedlings continued to grow normally. Chromosomes of the these interspecific self-sterile F1 hybrids were doubled by tissue culture. Amphidiploid of F1 hybrid was self-fertile. Starting with amphidipliod, a wystematic backcross (BC) program was set up with NC82 as recurrent parent. In the BC5C2 generation, the resistant plant was selected. This resistant line, KF8833-1, had 48 chromosome and secreting glandular trichomes. It flowered 2days later than NC82, and stalk height, leaves per plant, leaf length and leaf width were similar to those of NC82.