• Korean Journal of Plant Resources
• /
• v.26 no.4
• /
• pp.516-518
• /
• 2013

A new leaf variegated cultvar 'White Edge' was developed by ethyle methane sulfonate(EMS) treatment on seed of Hosta minor. Among induced leaf variegated plant, some with white color on the edge of the leaves was selected. They were cultivated via vegetative propagation. 'White Edge' was finally selected through the test of characteristics from 2003 to 2005. Assessment of botanical characteristics was conducted for three years. The major characteristic of these cultivar is that they maintain uniformly all year round. 'White Edge'(Grant No.1880) was registered to the Korea Seed and Variety Service(KSVS) for commercialization in 2007. These cultivar are useful as materials for pot or as ground cover plants.

• Korean Journal of Environment and Ecology
• /
• v.22 no.6
• /
• pp.648-657
• /
• 2008

This research was conducted to investigate the breeding density and seasonal food items of the magpies in Jeju Island and the near-manned islets. The examination of nest distribution to determine breeding density was performed during breeding season from February 2006 to April 2008, and that of food items from May 2006 to February 2008. A total of 2,113 nests were found across Jeju Island, the average density was $1.33\;nest/km^2$, and the magpies were distributed up to 600 meters above the sea level. The nest density was the highest in the central areas of Jeju Island, with 688 nests at $3.61\;nest/km^2$, while that in the eastern areas was the lowest, with 214 nests at $0.66\;nest/km^2$. In terms of the number of nests depending on the height above the sea level, 1,172 nests, which was equivalent to the density of $1.85\;nest/km^2$, was observed below 100m and highest among the intervals of height, but 16 nests found at 500-600m were the lowest, corresponding to $0.20\;nest/km^2$. The number of nests found in the manned islets near Jeju Island was eight in Biyang-do with the density of $15.38\;nest/km^2$, nine in U-do with $1.49\;nest/km^2$, and one in Gapa-do with $1.15\;nest/km^2$, whereas none of nests were observed in Mara-do. The contents of stomach consisted of 17 types of prey sources including countless bones, eggshells, plants, and seed, most of which were the individuals of the order Coleoptera. In spring and summer, the foraging frequency for invertebrate animals such as insects was high, but less than 30% in winter. In contrast, the magpies preyed upon plants and seeds at the frequency of 10% and 30%, respectively, in spring, while the foraging frequencies for both of them were 100% in winter and higher than any of other seasons. Eggshells and bones of birds were also detected infrequently. If the density of the magpies, which may play role as the upper predator within the ecosystem, increases, it would be expected to affect directly the reduction of the number of the species and population of endemic animals such as small birds and reptiles, etc. Therefore, it is considered that long-term monitoring for the density of the magpies and precaution is prerequisite to minimize adverse effects on ecosystem.

• Weed & Turfgrass Science
• /
• v.7 no.3
• /
• pp.275-282
• /
• 2018

Miscanthus species are known as a genus of eco-friendly and low-maintenance cost ornamental grasses. Plug and cutting methods were tested for multi-propagation of most promising ornamental Miscanthus species in greenhouse and field plot. The plug formation period with three different cell sizes with four cultivars (M. sinensis 'Andersson', 'Strictus', 'Gracillimus', 'Variegatus') were evaluated the seedling development stages with two irrigation types of the over-head and the bottom watering in greenhouse and field plot afterward during 2015-2016 season. In seedling plug test, the size of tray cell affected the plug formation. Bottom irrigation resulted positively on plant height, weight, root and tiller development compared with the over-head irrigation. Plug cell size affected the plant growth in the field after transplanting. All of the 3 Miscanthus species showed higher rates of successful propagation at the lower nodes before inflorescence formation (vegetative growth stage). To analyze the survival factors of M. xgiganteus cutting, the cutting time, node part, and culm diameter were tested as independent variables with the binary logistic model. The survival probability was influenced by node part and culm diameter significantly. The third and fifth node parts showed 0.12 (8X higher failure probability) and 0.02 (50X higher failure probability) times less survival probability. It means the survival probability will be increased by using older and lower part of cuttings during a vegetative growth stage before inflorescences of M. xgiganteus.

• Horticultural Science & Technology
• /
• v.28 no.6
• /
• pp.913-920
• /
• 2010

This study was conducted to improve the seed germination by low temperature and $GA_3$ in $Orostachys$ $japonicus$ A. Berger (Jirisan) and $O.$ $iwarenge$ (Mak.) Hara (Jejuyeonhwa), Korean native plants. Observation of the seeds using a stereo microscope showed that all seeds of the two species have wrinkled surface and oblong shape. Seed size ranged 0.77-1.00/0.25-0.37 mm (length/width), indicating that the seeds are minute seeds. When the seeds of two $Orostachsis$ species were sown into petri-dish and placed in a plant growth chamber of 10, 15, 20, or $25^{\circ}C$, 'Jirisan' showed seed germination below 20% at all temperatures and 'Jejuyeonhwa' 80% at only $10^{\circ}C$. Seed germination of 'Jirisan' increased up to 44% at $10^{\circ}C$ by low temperature ($4^{\circ}C$) storage for 10 days, but decreased again at storage for more than 20 days. The seeds of 'Jejuyeonhwa' showed a large increase in seed germination by low temperature for 20-30 days, which was 95% at $10^{\circ}C$, but low temperature for more than 40 days significantly decreased seed germination. Dipping treatment in GA3 solution of $50-400mg{\cdot}L^{-1}$ for different periods (3, 6, 12, and 24 hrs) remarkably improved germination rate and speed in both species, 80-100% in 'Jirisan' and 90-100% in 'Jejuyeonhwa' at all concentrations and dipping times used in this study.

• Korean Journal of Environment and Ecology
• /
• v.35 no.6
• /
• pp.644-658
• /
• 2021

Understanding the functional traits of dominant species in urban ecosystems provides insight into species' trait adaptation and ecosystem function in response to fragmented and isolated urban vegetation and reduced biological interactions. This study compared means and variances of environmental factors (geographic, meteorological, and soil attributes) and 4 leaf traits (leaf area, specific leaf area, leaf dry mass content, and leaf shape index) and 7 reproductive traits (fruit width, fruit length, fruit shape, fruit dry weight, fruit dry matter content, seed weight, and seed ratio) measured of 40 Sorbus alnifolia individuals in four mountainous areas south of Seoul downtown, South Korea. We then performed the multivariate analysis of trait combinations. While the measured environmental factors indicated the individuality of the survey sites, the urban vegetation was drier and had a longer growth period. The leaves of S. alnifolia in the urban areas were smaller and heavier, and the fruits produced longer and lighter seeds, showing the traits affected by long urbanization. The study confirmed changes in the growth and reproduction mechanism of the S. alnifolia population under the urban environment, indicating reduced biological interaction due to vegetation fragmentation and isolation. This study provides limited but distinct ecological information about the function and persistence of key species in cities with a reduced scale of biological interactions and many negative environmental factors such as air pollution.

• Weed & Turfgrass Science
• /
• v.3 no.4
• /
• pp.305-311
• /
• 2014

The cultivation area and use of genetically modified (GM) crops have been increased continuously over the world. Seed distribution and transgenes to environmental ecosystem is one of the most important factors in risk assessment and risk management of GM crop. Safe management for the development and commercialization of GM crops is required according to The Act on Transboundary Movements of Living Modified Organisms,etc (LMO Act) in Korea. This study was conducted to setup the environmental monitoring system of GM zoysiagrass (event JG21 and JG21-MS). The monitoring was performed in 4 GMO confined fields, Sungwhan, Ochang, Jeju University and Jeju Namwon. In the result of monitoring, we could not found any gene flow and distribution of GM zoysiagrass in the 3 fields, but one spill of JG21 was found in the Namwon field in 2012. These results suggest that continuous monitoring is necessary to detect the occurrence of GM zoysiagrass for preventing genetic contamination in natural environment.

• Journal of Wetlands Research
• /
• v.15 no.3
• /
• pp.381-386
• /
• 2013

The increased $CO_2$ concentration and temperature affect ecological responses of plants. In order to know the effects of global warming on the Viola raddeana Regal, endangered aquatic plant designated by the Ministry of Environment Korea, this study was investigated at control and treatment(increased $CO_2$ concentration + increased temperature) in glasshouse. Then, autecological responses of V. raddeana were monitored and measured. As a result, shoot length, number of fruits per plant, number of branch per plant, number of seeds per fruit, number of fruits per branch, and weight of 10 seeds were higher in control than in treatment. number of leaves per branch was higher in treatment than in control. Length of axis, length of branch and number of leaves per plant were not different between in the control and in the treatment. These results demonstrated that the reproductive response of V. raddeana might be negatively influenced by increased $CO_2$ concentration and temperature. The global warming will be one of the main causes of extinction for V. raddeana Regal.

• FLOWER RESEARCH JOURNAL
• /
• v.16 no.2
• /
• pp.134-142
• /
• 2008

This work aims to obtain basic information for seed propagation of Hydrangea serrata for. acuminata. The germination percentage of the seeds taken on 15 November, 30 December, and 23 January was $90.0{\pm}4.16%$, $84.4{\pm}5.52%$, and $88.9{\pm}2.40%$, respectively. This suggest that seeds of Hydrangea serrata for. acuminata are non-dormant seeds. The optimum temperature for germination was $25^{\circ}C$ and light was necessary. Most of the growth parameters (shoot and leaf length, stem diameter, root length, no. of roots, T/R ratio, and fresh and dry wts.) were significantly greater at $25/20^{\circ}C$ and $25^{\circ}C$ than at the other temperatures. Low T/R ratio at relatively cool temperatures (15 and $20^{\circ}C$) was caused by suppressed top growth. In light quality treatment, red light (RL) significantly enhanced stem elongation. The greatest photosynthetic pigments (total chl, chl a/b, and carotenoid) were observed in seedlings grown in blue light (BL), followed by seedlings grown in RL+BL. When blue light was added, higher pigment contents were found. Effect of plug cell size (50, 72, 128, 162 and 200 cells) on the growth of seedlings was investigated. The highest top growth was observed in seedlings grown in 50 cell trays, followed by seedlings grown in 72, 128, 162, and 200 cell trays. However, there was no significant differences between 162 and 200 cell trays. Especially, smaller size leaves were observed in seedlings grown in smaller cell trays (lower volume and high plant density).

• Journal of Plant Biotechnology
• /
• v.49 no.3
• /
• pp.163-170
• /
• 2022

There is a continuous rise in the commercialization of living modified (LM) organisms worldwide. While LM plants have not yet been cultivated in South Korea, research, development, import of products, and registration of related research facilities are progressing. LM plants should be tested in greenhouses and fields during development. Furthermore, environmental risk assessment and safety management should be performed before their release into the environment. Research on LM plant development is conducted in laboratories as well as confined greenhouses and fields. Safety management regulations are provided as combination standards for the LMO Act in each research district. The accidental release of the LM petunia in Japan was a significant incident related to LM plant research. It implies that normal plants within the distance of crossing should be regarded as LM plants. In the United States, LM creeping bentgrass was released into the environment, thus necessitating the establishment of stringent measures to prevent the scattering of LM plant seeds by wind or other mediums. In South Korea, LM Zoysia and LM cotton were released through rainwater. Therefore, safety measures that prevent LM seed mixing and plant vegetative propagules escaping into the environment via rainwater must be established. Preventing the dispersal of unapproved LM plants requires significant time, expenditure, and effort. Researchers should first identify the impact of LM plants on the ecosystem, and steps to avert their environmental release must be implemented.

• Journal of Korean Society of Forest Science
• /
• v.86 no.2
• /
• pp.128-134
• /
• 1997

An effective in vitro multiplication method was developed for clones of Populus davidiana Dode. Ten different media were tested for their effect on shoot multiplication. Both MS and LP medium with 0.2mg/l BAP appeared to be the best for the shoot multiplication with the rate of 9 shoots per explant. There were significant differences among the clones in both multiplication rate and shoot growth. While some clones did not require BAP to promote shoot formation, others did. More than 60% of in vitro shoots rooted on the half-strength GD medium containing 0.2mg/l IBA.