• Korean Journal of Plant Resources
• /
• v.30 no.6
• /
• pp.612-617
• /
• 2017

The preservation of pear germplasm, like that of other clonal germplasms, is difficult because it requires conservation of whole plants or their tissues. Among the currently available methods for long-term conservation of clonal germplasm, cryopreservation of shoot tips is the most reliable and cost- and space-effective option. Alginate-coated axillary shoot tips from in vitro-grown pear were conserved successfully in liquid nitrogen (LN) following dehydration. Shoot recovery from cryopreserved shoot tips was improved greatly after 8 weeks of cold acclimation, but recovery decreased slightly after then. The highest regeneration rate was observed when in vitro shoot tips were preincubated in MS (Murashige and Skoog) medium with 0.3 M sucrose for 48 h, and when alginate-coated shoot tips were precultured in MS medium with increasing sucrose concentrations (0.5 M and 0.7 M) for 8 and 16 h, respectively. When the encapsulated beads were dehydrated for up to 7 h [25% water content (fresh weight basis)] under laminar flow, the highest regeneration rate was observed in "BaeYun No. 3" (55.7%) and "Whanggeum" (43.3%) after warming from LN. This technique is useful as a practical procedure to cryopreserve plant material that is sensitive to freezing of the surrounding cryoprotectant medium. Therefore, this technique appears to be promising for the cryopreservation of shoot tips from in vitro-grown plantlets of pear germplasm.

• Korean Journal of Food Science and Technology
• /
• v.45 no.6
• /
• pp.675-681
• /
• 2013

We assessed the quality of a bamboo shoot vinegar produced in Damyang-gun in terms of parameters that included acidity, mineral contents, amino acids, and flavonol aglycones. The flavor compounds of the bamboo shoot vinegar were also analyzed using the stir bar sorptive extraction (SBSE) method. The acidity of the bamboo shoot vinegar was 4.49%, which was the lowest value among the commercial vinegars studied. The bamboo shoot vinegar had a lower concentration of Na (8.36 mg/100 g) than the other commercial vinegars. There was a relatively large amount of tyrosine and lysine in the bamboo shoot vinegar. The concentration of quercetin, a flavonol aglycone, was 3.29 mg/100 g. The results of the flavor analysis showed that hexanal, 2-furancarboxaldehyde, and benzaldehyde were high in the bamboo shoot vinegar. Oleamide, a compound that is known to induce sleep, was first found in bamboo shoot vinegar using the SBSE method.

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.6
• /
• pp.479-484
• /
• 2000

This study was conducted to examine the effects of explant sources and plant growth regulators on mass propagation of Cyclamen persicum. Tuber, cotyledon, and petiole tissues were cultured on MS medium supplemented with different concentrations and combinations of auxins and cytokinins. Shoots were not induced from calli on cotyledon and petiole explants cultured on MS medium containing various concentrations of 2,4-D or NAA. However, multiple shoots were formed directly from tuber explants cultured on the medium containing 0.5 and 1.0 mg/L 2,4-D or NAA. In MS medium with cytokinin alone, TDZ was more effective in shoot formation than BA or kinetin in all explants. The combinations of NAA and BA was found to be most effective in shoot formation from tuber, cotyledon and petiole explants. Especially, shoots were formed from all the tuber explants on the medium containing 0.5 mg/L of NAA and BA. Hormonal effects on root formation were examined by subculturing single shoots on MS medium containing NAA or IBA. The medium with 0.5 mg/L IBA was most effective in root induction and subsequent plantlet regeneration.

• Journal of Plant Biotechnology
• /
• v.36 no.4
• /
• pp.373-383
• /
• 2009

To set efficient transformation system in chrysanthemum, thirty-four chrysanthemum (Dendranthema grandiflorum Kitamura) varieties were collected and cultured for shoot regeneration. Five varieties, ‘Shuho-no-chikara', ‘Zinba', ‘Baekma', ‘Pink pride' and ‘Keumsu' of them were selected, because they had a high shoot regeneration efficiency. MS medium containing 1.0 mg/L NAA and BA respectively was very adequate for shoot regeneration in those varieties. MS medium with 3.0 mg/L NAA and 1.0 mg/L kinetin in ‘Shuho-no-chikara' and the medium with 0.5 mg/L NAA and 3.0 mg/L BA in ‘Keumsu' were also suitable for shoot regeneration. The most efficient callus induction and shoot regeneration were obtained on MS medium. Shoot regeneration was enhanced more than 8% on MS medium with 0.3% phytagel and 10-15 mg/L putrescine. The best cultural material for shoot regeneration was stem. When stem was used as a culture material, shoot regeneration rate was increased more than 26% and the days to shoot regeneration was shortened about 14 days.

• Korean Journal of Plant Tissue Culture
• /
• v.24 no.5
• /
• pp.263-268
• /
• 1997

Effects of plant growth regulators and condition on shoot induction from internode explants of Actinidia arguta were investigated. Optimal condition for shoot induction was obtained when internode explants were cultured on MS medium containing 3.0 mg/L zeatin. The frequency showed about 62.5% under darks condition at 27$^{\circ}C$ after 6 weeks of culture. Regenerated shoots were rooted on WPM medium supplemented with 0.5 mg/L NAA and the regenerants were acclimated to an artificial soil with mixture (perlite : vermiculite = 1:1, v/v) for further growth and successfully transplanted to the soil in a highly humidified greenhouse. Histological observations revealed that meristemoids were formed from small and isodiametric cells, and then developed to shoot primordia.

• Korean Journal of Plant Resources
• /
• v.31 no.6
• /
• pp.684-694
• /
• 2018

This study describes the successful establishment of a cryopreservation protocol for Citrus limon cultivars: 'Frost Eureka limon' and 'Cook Eureka limon', using a droplet-vitrification method. The shoot tips that were excised from in vitro grown seedlings of the two cultivars were preserved in liquid nitrogen (LN) and successfully regenerated into whole plants. Excised shoot tips were pre-cultured for 1 or 2 days in 0.3 M and 0.5 M sucrose solutions at $25^{\circ}C$ and incubated in a loading solution (LS) composed of 17.5% glycerol + 17.5% sucrose in Murashige and Skoog (MS) medium for 40 min at $25^{\circ}C$. Prior to direct immersion in LN for 1 h, the shoot tips were dehydrated with plant vitrification solution 2 (PVS2) at $0^{\circ}C$ or PVS3 at $25^{\circ}C$. The frozen shoot tips were re-warmed and unloaded with 1.2 M sucrose in $\text\tiny{^1/_2}$ MS for 30 min at $25^{\circ}C$. Shoot tips were post-cultured overnight on survival medium and then micrografted onto 'trifoliate orange' (Poncirus trifoliate (L.) Raf. seedling rootstocks for recovery and to produce whole plants. The highest regrowth rates were 53.5% and 50.3% for cryopreserved shoot tips of 'Frost Eureka limon' and 'Cook Eureka limon', respectively, when pre-cultured in 0.3 M and 0.5 M sucrose concentrations in a sequencing manner, with LS and treated with PVS2 for 60 min at $0^{\circ}C$. We also investigated whether the ammonium ion concentration on post-culture medium affected the viability of the cryopreserved Citrus shoot tips. The viability of cooled samples, following culturing on woody plant media (WPM) containing $\text\tiny{^1/_4}$ ammonium nitrate overnight before micrografting, was the highest (70.3%) in 'Frost Eureka limon'. The study described here is a cost-effective and safe method to conserve Citrus fruit cultivars, for the improvement and large-scale multiplication of fruit plants and for breeding disease resistance.

• Korean Journal of Agricultural Science
• /
• v.50 no.4
• /
• pp.723-734
• /
• 2023

Erwinia pyrifoliae, which causes black shoot blight in apple and pear trees, was first identified in Korea in 1995. Extensive measures are typically used to control the disease by eradicating trees in diagnosed orchards, owing to the detrimental impact of the disease on apple and pear production. However, despite governmental efforts, the disease has continuously spread. In this study, we analyzed the current status of the black shoot blight occurrence in apple and pear orchards between 1995 to 2022. Our findings reveal that over the past 28 years, black shoot blight has occurred in 26 cities and districts across five Korean provinces. The affected regions are predominantly concentrated in the northern part of Korea, including the Gangwon and Gyeonggi provinces. Furthermore, black shoot blight has gradually expanded to the northern provincial regions of Chungbuk, Chungnam, and Gyeongbuk, which are centrally situated in Korea. Furthermore, the occurrence pattern of black shoot blight differed between apple and pear orchards; in apple orchards, black shoot blight occurred consistently each year, with a sudden increase in cases in 2020; however, in pear orchards, it has considerably decreased since 2007. To the best of our knowledge, this is the first comprehensive report on the occurrence of black shoot blight in apple and pear trees in 28 years, and the results will provide valuable insights for future disease management strategies.

• Journal of Plant Biotechnology
• /
• v.1 no.2
• /
• pp.97-100
• /
• 1999

In order to establish in vitro propagation method of sundew, Drosera rotundifolia L., the effects of MS medium concentration, cytokinin type and concentration, pH, and auxin type and concentration on shoot proliferation and root formation were investigated using shoots at 3 month after seed germination. The highest shoot production was obtained with the half strength of MS ($\frac{1}{2}$ MS) medium than with any other strength of MS medium tested. Addition of kinetin or BA in $\frac{1}{2}$ MS medium was strongly suppressed shoot proliferation. The suppression of shoot proliferation was more effective in BA-supplemented $\frac{1}{2}$ MS medium than kinetin-supplemented. The optimum pH of the media for shoot proliferation was pH 5.7-6.7. Shoots were subcultured in $\frac{1}{2}$ MS medium supplemented with 0.5mg/L 2,4-D for rooting every 8 weeks. All subcultured shoots produced extensive root systems after 5 to 6 week culture. Plantlets after root development were planted in plastic pots filled with moss. The survival rate of plantlets was almost 100%. On subculturing every 8 weeks, hundreds of the plants were propagated from a single plant within a year.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.6
• /
• pp.515-518
• /
• 1998

The effect of ethylene on the proliferation of rhizomes and plant regeneration were investigated from rhizome segment culture of Cymbidium niveo-marginatum. Ethylene levels in the rhizome culture vessels were reached a maximum after 8 days of culture; total amount of ethylene evolution was much on the initiation of shoot induction than of rhizome proliferation. The treatment with ethephon on rhizomes was inhibited in the proliferation of rhizome and the growth of shoot length; however, the treatment was effective on shoot induction from rhizomes. Aminoethoxyvinylglycine(AVG) 1mg/L was effective on the proliferation of rhizomes and shoot induction from them; however, the proliferation of them was inhibited, and the growth of shoot length was significantly promoted at the concentration of 10mg/L AVG. The presence of $\textrm{AgNO}_{3}$ inhibited in the proliferation of rhizomes and shoot induction from them.

• Korean Journal of Medicinal Crop Science
• /
• v.14 no.4
• /
• pp.225-228
• /
• 2006

To acquire the normal regeneration of plantlets, we investigated combinations and concentrations of plant growth regulations for optimal conditions of adventitious root formation. Based on the previous study, we performed callus and shoot induction. When induced shoot was transferred into a rooting medium containing plant hormones, it wilted and died. Thus, the shoot proliferated on 1/2 MS medium for 10 days and was then treated with MS medium supplemented with 3.0 mg/L NAA for 3 days. Adventitious root formations were observed after shoot planlets were transferred to 1/3 MS medium. The concentrations of salt and sucrose were gradually reduced in MS medium and the rooted plantlets were transferred for acclimatization into a mixture of peatmoos : perlite (3 : 2).