• The Plant Pathology Journal
• /
• v.18 no.3
• /
• pp.126-129
• /
• 2002

Infected sweet potato (Ipomoea batatas) showing symptoms of sunken veins, stunting, mosaic, and mottling were collected from Gimje, Cochang, Iksan, and Haenam provinces in Korea. Electron microscopic (EM) observation of the infected tissue revealed rod and filamentous rod type virus particles of various lengths. Western blot analysis of the protein samples extracted from infected sweet potato and partially purified virus identified the isolates as Sweet potato feathery motile virus (SPFMV), Sweet potato latent virus (SwPLV), and Sweet potato chlorotic stint virus (SPCSV). Sweet potatoes were occasionally infected with more than one of these viruses. This is the first report of SwPLV and SPCSV in Korea.

• Plant Biotechnology Reports
• /
• v.2 no.4
• /
• pp.267-270
• /
• 2008

We have successfully used the low-pressure BioWare gene gun, developed for gene transfer in animal cells, for plant tissues. The BioWare device is easy to manipulate. Just 50 psi helium pressure was sufficient to transfer foreign genes into the aleurone layer and embryo of maize without causing tissue damage in the impact area. As shown by expression signals from invasive histochemical ${\beta}-glucuronidase$ (GUS) activity, the foreign reporter gene expressed well in bombarded tissues. This successful GUS-transient expression extends the application of this low-pressure gene gun from animal cells to plant tissues.

• Korean Journal of Plant Resources
• /
• v.22 no.6
• /
• pp.518-521
• /
• 2009

High productivity of ginger (Zingiber officinale Roscoe) was obtained from the rhizome produced by shoot-tip culture with Korean native variety, Seosanjong. Seed rhizomes induced by shoot-tip culture were successfully established in the field. The rhizomes induced by both plant or rhizome were higher in emergence rate and faster in days to emergence than those of home seed production. The seed rhizome production induced by shoot-tip culture was two times heavier than that of home seed production. These results suggest that shoot-tip culture might be one of mass propagation methods in seed rhizome of ginger plant.

• Current Research on Agriculture and Life Sciences
• /
• v.32 no.4
• /
• pp.175-177
• /
• 2014

This is the first report describing the seasonal conditions affecting shoot regeneration by the chrysanthemum cv. Baeksun. The shoot regeneration from petal explants was found to be more favorable from September to December, reaching the highest values in December. In addition, the quality of the shoots was also influenced according to the season of the explant collection, where healthy and uniform plants were derived from the explants collected in December. Choosing the proper season for explant collection affected the successive plant growth parameters (i.e., plant height and fresh weight). Thus, the current results strongly suggest that season plays an important role in plant tissue culturing, which is an essential tool for micropropagation and Agro-bacterium-mediated genetic transformation studies.

• Journal of Plant Biotechnology
• /
• v.50
• /
• pp.255-266
• /
• 2023

Hyperhydricity is a physiological anomaly that significantly affects the growth and proliferation rate of crops cultivated by tissue culture techniques. To better understand the mechanisms that govern hyperhydricity incidence, we examined the effects of several media components, particularly cytokinin and gelling agents. These elements were found to be influential in both in vitro propagation and the development of hyperhydricity. Our study revealed that Arabidopsis thaliana seedlings had a greater manifestation of hyperhydricity symptoms when exposed to high cytokinin concentrations compared with the control. The presence of gelrite led to the manifestation of hyperhydric symptoms by elevated water build-up in the apoplast. The phenomenon of stomata closure was observed in the hyperhydric leaves, resulting in an increased ability to retain water and a decrease in the transpiration rates when compared to their respective control leaves. Additionally, histological examinations of the cross sections of hyperhydric leaves revealed an irregular cellular arrangement and large intercellular spaces. Furthermore, hyperhydric seedlings displayed impaired cuticular development in comparison to their normal seedlings.

• The Plant Pathology Journal
• /
• v.40 no.4
• /
• pp.399-407
• /
• 2024

Dieback disease in mango trees has been observed in Indonesia, particularly in Java Island, with the causal agent remaining unidentified. One of the important pathogens that are responsible for causing mango dieback is Colletotrichum. Field surveys were conducted in various mango cultivating areas in Java Island, Indonesia to assess prevalence of Colletotrichum as dieback disease pathogen. Eleven Colletotrichum isolates were recovered from symptomatic dieback twigs and morphologically characterized. Genetic diversity fingerprint analysis was carried out using rep-PCR. Phylogenetic analysis identified isolates as belonging to Colletotrichum asianum and Colletotrichum cairnsense using partial sequences of four gene regions, including ITS, ACT, GAPDH, and TUB2. Pathogenicity tests on mango seedlings cv. Arumanis showed that all fungal isolates were responsible for causing dieback symptoms. Subsequently, symptomatic tissue was reisolated to fulfill Koch's Postulate. This study represented new funding for two species of Colletotrichum causing mango dieback in Indonesia.

• Horticultural Science & Technology
• /
• v.33 no.3
• /
• pp.317-325
• /
• 2015

Peach (Prunus persica L.) is a model species for stone fruit studies within the Rosaceae family. Auxin plays an important role in the development of peach fruit. To reveal the distribution of auxin in the tissues of peach fruit, immunohistochemical localization of IAA was carried out in the seed, mesocarp, and endocarp in developing peach fruit using an anti-indole-3-acetic acid (anti-IAA) monoclonal antibody. A strong IAA signal was observed throughout the outer and inner integument during peach fruit development, and the distribution was zonal. The IAA signal was mainly focused in mucilage layers in the outer integument. The outer integument may function to produce or store IAA in the seed; a strong IAA signal was detected in the cells around the vascular tissue, whereas a weak IAA signal was located in the vascular tissues. In the mesocarp, the cells around the vascular bundle tissue gave rise to an IAA signal that increased in the late phase of fruit growth, which coincided with a significant increase in fruit growth. The distribution of IAA, however, was changed when fruit was treated with auxin transport inhibitors NPA (1-N-naphthylphthalamic acid) or TIBA (2, 3, 5-triiodobenzoic acid); in mesocarp tissues, an IAA signal was detected mainly in vessels of the treated fruit. During the critical period of endocarp lignification, the vessel lignification process was negatively correlated with IAA signal. The present results confirmed that the distribution of IAA was different in various tissues of peach fruit according to the developmental stage. This research provides cytological data for further study of the regulatory mechanism of auxin in peach fruit.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.163-163
• /
• 2017

A deletion analysis of the Oryza sativa dihydroflavonol reductase (DFR) promoter defined a 25 bp region (-386 to -362) sufficient to confer pericarp-specific expression of ${\beta}$ -glucuronidase(GUS) reporter gene in transgenic rice. Site-specific mutagenesis of these conserved sequences and subsequent expression analysis in calli which transiently expressed the mutated promoter::GUS gene showed that both bHLH (-386 to -381) and Myb (-368 to -362) binding sites in the DEL3 (-440 to 70) promoter were necessary for complete expression of the GUS gene including the tissue-specific expression of DFR::GUS gene. The GUS gene was expressed well in the mutated Myb (-368 to -362) binding site, but not as strong as in normal condition, implying that the Myb is also necessary to express GUS gene fully. Also, we found the non-epistatic relation between Rc and DFR. There were no changes of expression patterns GUS under the Rc and rc genotypes. Thus, DFR expression might be independent of the presence of functional Rc gene and suggested that Rc and Rd (DFR) share the same pathway controlling the regulation of flavonoid synthesis but not a direct positive transcriptional regulator of DFR gene.

• 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.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.5
• /
• pp.277-281
• /
• 2001

Embryogenic callus induction and plant regeneration methods were developed for native Kentucky bluegrass (Poa pratenes L.) ecotypes. Mature caryopses and immature inflorescences (20 mm in length) of 4 native ecotypes and 5 foreign cultivars were plated on MS medium (30 g/L sucrose, 3 g/L Phytagel) supplemented with 1 mg/L 2,4-D, and cultured in the dark at 24$^{\circ}C$. Most explants formed calli, but more embryogenic calli were induced from the explants of immature inflorescences than caryopses which produced mostly non-embryogenic rooty calli. In P77 ecotypes, immature inflorescence explants formed embryogenic calli with the rate of 62~95%, and those of field-grown plants were more efficient than greenhouse-grown ones in embryogenic callus induction. Plantlets were regenerated from the embryogenic calli when they were transferred to hormone-free MS medium, and grew to maturity without morphological variations in greenhouse.