• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.43-48
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• 2013

Oreorchis coreana Finet is threatened globally by over-collection from its natural habitats for horticultural purposes. Its rarity in nature makes this plant one of the most endangered species in Korea. In this study, we investigated the effects of sodium hypochlorite (NaOCl) on orchid seed viability and seed germination. An in vitro bioassay swelling test using immature seeds was compared with a standard chemical procedure using triphenyl tetrazolium chloride (TTC) to test seed viability. In general, the bioassay was more appropriate for estimating embryo viability after a prolonged pre-treatment (more than 1 h) in 1% NaOCl, a surface sterilant often used to enhance germination of seeds of terrestrial plants. Therefore, an efficient method for investigating in vitro swelling of immature seeds is urgently needed. We established a method for determining the viability and swelling of O. coreana seeds via in vitro examination of immature seeds. Treatment of immature seeds with 1% NaOCl for 10 min greatly enhanced the extent of swelling of immature zygote embryos when compared to untreated seeds. These data obtained here appear to be comparable to viability and swelling that occurs in O. coreana seeds via asymbiotic germination.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.295-305
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• 2011

Many studies have suggested the positive effects of grazing by large herbivorous mammals on seed dispersal, but little is known about how herbivores could affect the fate of ingested seeds. This study examined the effects of seed ingestion by sika deer (Cervus nippon) on seed fate in a temperate grassland established in an urban park long resided by high densities of sika deer. I compared species composition and seasonal traits of seed abundance and maturity in the grassland community with those in deer fecal pellets. In total, 27 herbaceous species were observed, including the predominant Zoysia japonica. Seed phenology and production differed among the three dominant species (Z. japonica, Digitaria violascens, and Hydrocotyle maritima). Pellets contained at least 26 species of herbaceous seeds, and their abundance differed among species. Of the 26 species, 15 were observed in the vegetation at the study site. The peak of seed abundance in pellets for the dominant species appeared 1 month after the peak of inflorescence production (but most of the inflorescences were immature and susceptible to digestion) and consequently corresponded to the peak of mature inflorescence. Because sika deer are likely to ingest seeds at any maturity stage in the grassland and immature seeds are less hardened, ingested immature seeds can suffer great losses. The results suggested that the survival of germable seeds with great losses of immature seeds may be a factor determining which plant species can be successfully dispersed by herbivores.

• Journal of Species Research
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• v.6 no.1
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• pp.68-75
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• 2017

We investigated the effects of sodium hypochlorite (NaOCl) and culture medium on embryo swelling and germination of Calanthe discolor Lindl., and established a method for determining the swelling and protocorm formation of C. discolor seeds via in vitro examination of immature seeds. Treatment of immature seeds with NaOCl greatly enhanced the extent of embryo swelling and protocorm formation of immature zygote embryos compared to seeds without NaOCl treatment. The effects of the culture media were also evaluated with regard to embryo swelling and protocorm formation of in vitro cultured seeds with and without NaOCl treatment. Additionally, the effects of white fluorescent light and red and blue LEDs lights on seedling growth in in vitro culture were examined. The most suitable condition for seedling growth after 12 weeks of culture was the red LEDs light with POM medium. These results show effective asymbiotic germination and growth of C. discolor.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.179-183
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• 1995

The brassinosteroid-like active principles from immature seeds of Zea mays were purified and identified as castasterone, teasterone, 28-norcastasterone and 6-deoxocastasterone by GC-MS analysis. Our work is probably the first report that showed the presence of brassinosteroids in Zea mays seeds.

• Journal of Plant Biotechnology
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• v.41 no.1
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• pp.44-49
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• 2014

In this study, we investigated the effects of sodium hypochlorite (NaOCl) and red or blue light-emitting diode (LED) light on embryo swelling and germination of Oreorchis patens (Lindl.) Lindl. A method for determining the swelling and protocorm formation in O. patens seeds through in vitro examination of immature seeds was established. NaOCl treatment of immature seeds was found to significantly enhance the extent of embryo swelling and protocorm formation in immature zygote embryos compared to those in the untreated controls. Additionally, the effects of white fluorescent light, and red and blue LED lights on embryo swelling and protocorm formation in in vitro cultured seeds were examined and compared to the conditions with or without NaOCl treatment. The most suitable light for embryo swelling and protocorm formation was the red LED light.

• Journal of Plant Biology
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• v.33 no.4
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• pp.271-276
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• 1990

Our study was carried out for plant regeneration via somatic embryogenesis from immature seeds of Bletilla striata. The highest frequency of embryogenic callus formation was obtained from the immature seeds (at 150 days after pollination) cultured on Hyponex and VW medium supplemented with 3 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) and 1 mg/l kinetin under the dark condition. Multiple somatic embryos were induced when embryogenic callus was transferred to VW medium without growth regulators under continued illumination. Somatic embryos were observed histologically with scanning electron microscopy. Regeneration of Bletilla striata was obtained from somatic embryos with a well-defined scutellum and coleoptile as well as with one or more shoot primordia and root primordia. We think that these methods for orchid multiplication must be useful to access clonal propagation of orchids.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.213-219
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• 2004

Zygotic embryos were excised from immature and mature seeds of the Himalayan yew, Taxus wallichiana. The embryos germinated precociously when kept in darkness for 5 weeks and developed into full seedlings within 10-12 weeks. The highest rate of embryo germination ($81\%$) was obtained in modified Lloyd & McCown' s woody plant medium containing macro and micronutrients at half strength supplemented with $1\%$ activated charcoal, which supported both the best embryonic growth ($43\%$) and seedling development ($32\%$). However, the supplementation of basal media with kinetin, thidiazuron, 6-benzyl aminopurine or $GA_3$ had no effect on the germination of the embryos. The embryos derived from immature seeds germinated but the frequency of embryonic growth was better in mature seeds. Stratification of seeds effected precocious germination of embryos. Seeds kept at $4^{\circ}C$ for 1 week germinated earlier and at a higher frequency irrespective of the stage of seed maturity, while the germination rate declined with prolonged cold treatment for 1 month at that same temperature. Analysis of taxanes in germinating seedlings revealed that root tissues contained high levels of taxol, 10-deacetyl-baccatin ill and baccatin ill as compared to shoots. Thus embryo culture technique appears to overcome the lengthy dormancy requirement of T. wallichiana seeds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.152-155
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• 2003

Burcucumber (Sicyos angulatus L.), used as a medicinal or rootstock for cucurbitaceous crops have shown high variation in seed maturity and size. This study was carried out to determine the effect of seed maturity and size on seed germination, seedling emergence and growth of burcucumber, Seeds collected from a native site were divided into small, medium and large ones after sorted to mature and immature ones. Their germination, seedling emergence and growth were done in indoor and a green house. Mature seeds showed higher germination and seedling emergence rate than immature ones. Regardless of their maturity, medium. and small seeds showed higher germination rate than large ones. Medium and large seeds, however, had the greatest and the least seedling emergence, respectively. Seedling height, number of true leaves areas of cotyledons and true leaves except hypocotyl length were increased with increased seed size although were not affected by the maturity. Cotyledon, leaf, hypocotyl, root and their total dry weights were greater in large mature seeds than large immature ones while increased with increased seed size in both maturities.

• Bulletin of the Korean Chemical Society
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• v.21 no.12
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• pp.1274-1276
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• 2000

• Applied Biological Chemistry
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• v.30 no.1
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• pp.54-59
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• 1987

Occurrence of two type brassinosteroid-like substances and less molecular weight substance than brassinosteroid were suggested in immature Vicia faba seeds extracts, which were purified using various chromatographic techniques, by Korean rice-lamina inclination test.