• Journal of Ginseng Research
• /
• v.23 no.3 s.55
• /
• pp.148-163
• /
• 1999

The efficacy of three auxins, viz. 2,4-0, NAA and dicamba, were compared for the induction of somatic embryogenesis in American ginseng (Panax quinquefolium L.). Somatic embryos (SEs) formed on ginseng cotyledonary, zygotic embryo and shoot explants after 8 weeks of induction by the auxin stimuli. Significantly more somatic embryos were induced by culture of any of the ginseng explants on media supplemented with $5{\mu}M$ 2,4-0 than any other auxin treatment. Shoots derived from somatic embryos had the greatest regenerative potential and zygotic embryos the least. Explants generated from green (unstratified) seeds gave similar or higher frequency of embryogenesis as the explants derived from stratified seeds. Histological and SEM studies confirmed that the regenerimts were somatic embryos. Somatic embryos germinated and developed into normal plants in $3\~6$ months. About $10\%$ of plantlets from second generation SEs formed flowers within 10 weeks, particularly on media supplemented with $GA_3$ The development of a regeneration system for ginseng through somatic embryogenesis is a necessary first step for mass propagation and genetic improvement of American ginseng.

• Journal of Ecology and Environment
• /
• v.42 no.4
• /
• pp.259-264
• /
• 2018

Background: Revegetating landfills can be a challenging task as the reclaimed soils are typically dry and have low nutrient content. Therefore, selecting suitable plant species is important for initial revegetation. The issue with current practices (in Korea) is that alien plant species have been typically selected for revegetation projects. In this context, this study selects and tests a set of native plant species for landfill revegetation, accompanied by the assessment of the landfill soils. Results: The soil of the landfill (landfill location) was in a very poor condition with high bulk density and low organic matter and nutrient contents. Among 10 tested species, only Brassica campestris showed high coverage and a sufficient number of individuals in study quadrats sown with seeds. Results suggest that plant species with heavy seeds are the only ones that can adapt to the environment of a typical landfill due to the site's aridity and low nutrient content. The reason is due to such species' superior wind resistance and the capacity to provide sufficient energy for the initial growth of the plants for survival in such landfill environment. Conclusions: This study recommends selecting plant species (1) with arid-adapted features and (2) whose seed weight is sufficiently heavy for survival at landfills or areas with a similar condition for future revegetation.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.144.2-145
• /
• 2003

This study was performed to investigate the incidence of Hosta uirus X (HVX), a Potexvirus, from cultivated hosta ornamental plants in Korea and to ascertain seed transmission of the virus from infected parent plant to progeny ones for breeding program of hosta plants. Infection rate of HVX in cultivated hostas was 25.6 ％ (11 out of 43 collected samples contained HVX) based on Western blot and RT-PCR detection methods. Most of HVX-infected hostas showed visible systemic leaf symptoms (mosaic, mottle, curling, stunting or combinations). Variability of HVX was confirmed by sequences of coat protein gene of individual isolates from different hostas. HVX was seed-transmitted on Hosta 'Blue Cadet'. The virus was detected from seeds, and sprouts and seedlings from the virus-contaminated seed sources. Over 7.5 ％ of seeds were HVX-contaminated surveyed in this study, Our data suggest that HVX can be transmitted by seed source, and indexing of the virus should be done for breeding program of Hosta.

• The Plant Pathology Journal
• /
• v.39 no.5
• /
• pp.513-521
• /
• 2023

Seed-borne diseases reduce not only the seed germination and seedling growth but also seed quality, resulting in the significant yield loss in crop production. Plant seed harbors diverse microbes termed endophytes other than pathogens inside it. However, their roles and application to agricultures were rarely understood and explored to date. Recently, we had isolated from soybean seeds culturable endophytes exhibiting in-vitro antagonistic activities against common bacterial and fungal seed-borne pathogens. In this study, we evaluated effects of seed treatment with endophytes on plant growth and protection against the common seed-borne pathogens: four fungal pathogens (Cercospora sojina, C. kikuchii, Septoria glycines, Diaporthe eres) and two bacterial pathogens (Xanthomonas axonopodis pv. glycines, Pseudomonas syringae pv. tabaci). Our experiments showed that treatment of soybean seeds with seed endophytes clearly offer protection against seed-borne pathogens. We also found that some of the endophytes promote plant growth in addition to the disease suppression. Taken together, our results demonstrate agricultural potential of seed endophytes in crop protection.

• Korean Journal of Plant Resources
• /
• v.29 no.5
• /
• pp.564-573
• /
• 2016

This research was performed to develop mass propagation method of round-leaved sundew (Drosera rotundifolia L.) for improving horticultural usefulness. Seeds were collected around Hwaseong-si, Gyeonggi-do in October of 2011 and experimented upon while being dry-stored at 4 ± 1.0℃ (darkness). Seed length of a major and minor axis were 1.58 ± 0.060 and 0.21 ± 0.016 ㎜, respecrively, and weight of 1,000 seeds was 6.24 ± 0.172 ㎎. Seeds were thus classified as ‘dwarf seeds’. Regarding the dormancy type, since round-leaved sundew seeds were dormancy broken and germinated at 20~30℃ under the light condition after wet-chilling treatment for 12 weeks, seeds were estimated to have physiological dormancy. Germination conditions of dormancy broken seeds were found to be 20℃ and light condition (54.7%), but germination decreased at higher temperature. Percent germination (PG), germination energy (GE), mean germination time (MGT) and T₅₀ were effectively improved by chemical treatment such as GA₃ 200 ㎎/L + kinetin 20 ㎎/L and wet-chilling treatment for 14 weeks. In conclusion these optimal conditions were thought to be a useful method for raising seedling uniformly.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2020.08a
• /
• pp.92-92
• /
• 2020

The phenolic contents in soybean seeds are affected by genetic and environmental factors. In the present study, 24 black soybeans and a control variety were grown in Korea and grouped as small (<13 g), medium (13 - 24.0 g), and large (>24 g) based on their seed weight. The total phenolic content (TPC) and antioxidant activities were analyzed and compared with their seed weight. The TPC was in the ranges 2.016 - 5.535, 1.992 - 4.679, and 1.829 - 4.621 mg GAE/g in small, medium, and large seeds with an average of 3.824, 3.108, and 3.626 mg GAE/g, respectively. The FRAP and DPPH activities were in the ranges 4.327 - 6.394 and 0.354 - 0.403 mg AAE/g in small seeds, 2.510 - 6.147 and 0.356 - 0.417 mg AAE/g in medium seeds, and 3.024 - 6.389 and 0.344 - 0.405 mg AAE/g in large seeds, respectively. Besides, ABTS activity was in the ranges 4.833 - 4.967, 3.636 - 4.871, and 4.554 - 4.956 mg TE/g in small, medium, and large seeds, respectively. Small seeds had the highest average FRAP (5.498 mg AAE/g) and ABTS (4.902 mg TE/g) activities while large seeds showed the highest average DPPH (0.387 mg AAE/g) activity although the variations were not significant (p > 0.05). TPC showed positive correlation with every antioxidant activity. However, the TPC correlation was significant (p < 0.05) only with DPPH (r = 0.673). Overall, small seeds presented a relatively high TPC and maximum antioxidant activities. Hence, black soybeans with small seeds could be important sources of high phenolic concentration and provide improved health benefits.

• Research in Plant Disease
• /
• v.29 no.4
• /
• pp.414-419
• /
• 2023

In 2023, a number of seeds suspected to be discolored black oat seeds on oat farms in Gangjin were observed and examined for fungal infection. The species Alternaria alternata was predominant, accounting for 84% of all fungal infections. The appearance and quality of seeds harvested in 2022 were compared with seeds harvested in 2023 from the same field. The lightness value was lower in the seeds harvested in 2023, while the electrical conductivity was higher in the seeds harvested in 2023. The content of avenanthramide was found to be 10 times higher in the 2023 seeds than in those harvested in 2022. The accumulated precipitation in Gangjin in May 2023 was 230 times higher than that in May 2022, and the average relative humidity was high. These conditions created an environment suitable for infection of A. alternata, which were thought to have caused discolored black oat seeds.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.10
• /
• pp.1763-1772
• /
• 2017

This study aimed to isolate and characterize antibacterial metabolites from Pharbitis nil seeds and investigate their antibacterial activity against various plant pathogenic bacteria. The methanol extract of P. nil seeds showed the strongest activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibition concentration (MIC) value of $250{\mu}g/ml$. Among the three solvent layers obtained from the methanol extract of P. nil seeds, only the butanol layer displayed the activity with an MIC value of $125{\mu}g/ml$ against Xap. An antibacterial fraction was obtained from P. nil seeds by repeated column chromatography and identified as pharbitin, a crude resin glycoside, by instrumental analysis. The antibacterial activity of pharbitin was tested in vitro against 14 phytopathogenic bacteria, and it was found to inhibit Ralstonia solanacearum and four Xanthomonas species. The minimum inhibitory concentration values against the five bacteria were $125-500{\mu}g/ml$ for the n-butanol layer and $31.25-125{\mu}g/ml$ for pharbitin. In a detached peach leaf assay, it effectively suppressed the development of bacterial leaf spot, with a control value of 87.5% at $500{\mu}g/ml$. In addition, pharbitin strongly reduced the development of bacterial wilt on tomato seedlings by 97.4% at $250{\mu}g/ml$, 7 days after inoculation. These findings suggest that the crude extract of P. nil seeds can be used as an alternative biopesticide for the control of plant diseases caused by R. solanacearum and Xanthomonas spp. This is the first report on the antibacterial activity of pharbitin against phytopathogenic bacteria.

• Korean Journal of Plant Resources
• /
• v.25 no.6
• /
• pp.700-706
• /
• 2012

Influences of different seeding dates on growth, seed yield, fatty acid composition and oil content were investigated in flax plants for two years. The results indicated that plant height in early seeding date was higher than that of delayed seeding dates during first season. Furthermore, seeding date also significantly affected the ripened seed rate and the rate increased with the delay in seeding date in first season. Seed yield in the first crop season was significantly higher than the second crop season. Palmitic acid showed variation in different seeding dates. Contrarily, stearic acid was stable and did not changed by different seeding dates. Linolenic acid was found in highest amount in all seeding dates consecutively in two cropping years. Highest oil content was recovered from the seeds of flax sown at 29 Apr. and May 9 in first and second cropping year respectively.

• Korean Journal of Plant Resources
• /
• v.1 no.1
• /
• pp.88-92
• /
• 1988

The study was conducted to determine the optimal basal media and the concentration of plant growth regulator for germination of seeds and growth of plantlet from Dendrobium monile. The results obtained were summarized as follows. Germination was similar in light and dark condition, but the growth of plantlet after germination was better under dark than under light condition in several media. Germination was best in Hyponex and Kyoto solution medium among the 9 media tested. The number of roots/shoot was most in the Hyponex medium containing 0,1ppm NAA and 1.Oppm BA.