• The Korean Journal of Ecology
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• v.21 no.3
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• pp.243-249
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• 1998

Radicoid structure of herbaceous communities in Mt. Kumbyung, Chunchon, Kangwon-Do was clarified emphasizing on the dominance of clonal plants in relation to vegetation development. In the total vegetation, 46% species identified were rhizomatous, 26% were species with tap roots, and 13% were stoloniferous species. Thus, all clonal species, including plants with bulb, corm and tuber, covered 62.8% of the total species. in the understory of Quercus, Pinus and Larix forests, 68.2% were clonal, which means 5% more compare to total vegetaion. Dominance of clonal plants became more conspicuous as their importance value was calculated. That is, they covered average 86% for the following three communities: 85% in Quercus, 95% in Pinus, and 76% in Larix, Especially, the rhizomatous plants were remarkable. Overall, clonal species dominated over the other radicoid types in terms of not only the number of species, but also the importance value. Dominance of these species was more peculiar in understory of forests, indicating the occupancy of clonal plants was related to the vegetation development.

• Journal of Environmental Science International
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• v.21 no.11
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• pp.1297-1305
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• 2012

Clonal plants combine sexual and clonal reproduction, which contribute differently to plant fitness. Reproductive analyses have highlighted the importance of clonal growth in shaping the spatial genetic structure in Potentilla conferta Bunge, a herbaceous rhizomatic clonal distributed in hot sand dunes. We investigated the reproduction system of P. conferta at two populations in Mongol and three natural populations in Uzbekistan. The measurements of 19 quantitative or qualitative morphological characters were taken on each of total individuals directly from their natural habitats. Some morphological characteristics between Mongolia and Uzbekistan populations showed a slight heterogeneity of variance. Especially, the length of internodes (LFI and LSI) and characteristics of root (LLR and NOR) were shown a significant difference between two countries (P<0.05). P. conferta of Uzbekistan has most ramets at short distance intervals 30~100 cm. In light conditions, P. conferta of Uzbekistan was significantly less resilience than P. conferta of Mogol. In drought conditions, although there was not shown significant difference, P. conferta in Uzbekistan was less resilience than that in Mogol. The core analysis indicates that P. conferta in Uzbekistan is the more resistant than that of Mongol and seems to do by sexual reproduction strategy during several strong environmental disadvantages such as drought events.

• Journal of Ecology and Environment
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• v.40 no.2
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• pp.89-106
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• 2016

Many plant species have two modes of reproduction: sexual and asexual. Both modes of reproduction have often been viewed as adaptations to temporally or spatially variable environments. The plant should adjust partitioning to match changes in the estimated success of the two reproductive modes. Perennial plants showed that favorable habitats in soil nutrients or water content tend to promote clonal growth over sexual reproduction. In contrast, under high light-quantity conditions, clonal plants tend to allocate more biomass to sexual reproduction and less to clonal propagation. On the other hand, plants with chasmogamous and cleistogamous flowers provides with a greater tendency of the opportunity to ensure some seed set in any stressful environmental conditions such as low light, low soil nutrients, or low soil moisture. It is considered that vegetative reproduction has high competitive ability and is the major means to expand established population of perennial plants, whereas cleistogamous reproduction is insurance to persist in stressful sites due to being strong. Chasmogamous reproduction mainly enhances established and new population. Therefore, the functions of sexual and asexual propagules of perennial or annual plants differ from each other. These traits of propagule thus determine its success at a particular region of any environmental gradients. Eventually, if environmental resources or stress levels change in either space or time, species composition will probably also change. The reason based on which the plants differ with respect to favored reproduction modes in each environmental condition, may be involved in their specific realized niche.

• Plant Resources
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• v.6 no.2
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• pp.89-93
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• 2003

This study was conducted to develop the clonal propagation technique through in vitro culture using basal stem explants in Phalaenopsis hybrid grown in vitro. The highest frequency of protocorm-like body (PLB) formation was obtained when basal stem explants were cultured on VW medium containing 30g/L sucrose, 500 mg/L activated charcoal, 150 ml/L coconut water, 1 mg/L NAA, 5 mg/L 2iP and 2.5g/L gel rite. PLBs transferred to Hyponex medium were regenerated to plantlets. Plantlets transferred to plastic pots containing spagnum moss were developed and successfully acclimatized under greenhouse. The flower was bloomingly opened in plants regenerated from basal stem explants. The flower was not different from both mother plant and plant induced through clonal propagation of Phalaenopsis hybrid.

• The Korean Journal of Ecology
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• v.14 no.3
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• pp.327-343
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• 1991

Clonal growth and rhizome architecture of calmagrostis epigeios, were studied in a 15-year old coastal reclamed land. As c. epigeios patch grew from center to margin radially over time, concentric annuli were added. the radial increases of the mature patch were 80~130cm/yr. the patch ages of c. epigeios estimated by relationships between the diameter and is radial increament, were 1~6year old. There were the marked variations of density, phytomass, shoot height and inflorecence frequency with increasing age of rhizome system within the patch. the maximum performance occurred at 2-year-old concentric annuli of the patch. The growth phasic continuum with aging was divided into 5 grwth phases ; pioneer, building, matyre, senile and degenerate. The rhizome aging had a more significant effect on the inflorescence frequency than on the other attributes. new rhizomes tended to diverge from the direction of the parent ramet by sympodial growth. in a 1-year-old patch, average length of rhizome segment was 7cm, average number of internode was 6, and the tillering frequency was 27%. The tillering in the early stage resultd in the increase of shoot density and the producation of multibranching rhizome. as the result of that, circular patchwas formed in a year. The branching structure based on such facts was represented graphically in branching degree of 60 and 100. therefore, c. epigeios with clonal growth may establish and grow vigorously earlier than other glycophytes in high salt conditions such as the coastal reclaimed land.

• Journal of Forest and Environmental Science
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• v.26 no.1
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• pp.31-36
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• 2010

Sixteen microsatellite markers (simple sequence repeat (SSR) markers) were employed to examine the genetic stability of 27 randomly chosen date palm (Phoenix dactylifera L.) plants produced through somatic embryogenesis with upto forty two in vitro subcultures. No microsatellite DNA variation was observed among all micropropagated plants. Our results indicate that the micropropagation protocol used for rapid in vitro multiplication is appropriate and suitable for clonal propagation of date palm and corroborated that somatic embryogenesis can also be used as one of the safe modes for production of true-to-type plants of date palm. This is the first report on the use of microsatellite DNA markers to establish the genetic stability in micropropagated date palm plants.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1996.05a
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• pp.41-62
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• 1996

Since 1966 tissue culture has been used as a tool for the production of disease indexed stocks from selected plants and their rapid (clonal) mass propagation through the procedure now referred to as micropropagation. The major advantages have been the rapid introduction of new plant cultivars, created within conventional and mutation breeding programmes, as healthy stock for beneficial distribution and the expansion of the world wide horticultural industry. (omitted)

• Current Research on Agriculture and Life Sciences
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• v.24
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• pp.1-8
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• 2006

When tea trees were introduced to Korea peninsular from China? Historically, Mr. Taeryum, an envoy of Shilla dynasty brought tea seeds from China during Tang dynasty and the seeds were planted at Jiri Mt. by the order of King Heungduk at AD828. During Koryo Dynasty(918 1392), Buddhism spread rapidly all over the country and the tea culture reached its highest stage of prosperity. At the Chosun Dynasty, however, the ceremonial drinking of tea vanished almost completely due to the flourishing Confucian tradition, a kind of substitution of Buddhism. But a few people have supported the traditional tea culture by themselves. Since the independence of Korea soon after the World War II at 1945, Korean War have been exploded at 1950. After economic evolution have been succeeded at 1980, the cultivation area of tea trees has been increased about 2,000ha and the cultural tradition of tea drinking has become popular again at a tea consume quantities amounted to 100g per capita at 2004. The northern limited area of tea plant is lined on the southern part of Korea peninsular. It is very small region compared to China about one million ha and to Japan over 60 thousand ha. It is problem not only the area of tea fields but also the methodology of tea cultivation, for examples without clonal cultivars and mechanical systems. WTO treatments was discussing with Korea, China and Japan government at 2005. Green tea custom is very high at 514% in Korea. If three countries will be agreed the imported tax will be cut off, the Korean tea farmers will be confused because of unstable situation of tea markets. All most of tea farmers should be made the tea fields by seeding not clonal propagation. Because of clonal cultivars have not developed in Korea, there have not been the research institutes for tea plants and manufactures before 1992. Now there are three research institute of tea in Korea; Tea Experiment Station at Bosung of Jeonnam Agricultural Research & Extension Services, Mokpo Experimental Station of National Institute of Crop Science, and Green Tea Cluster Institute of Hadong. Mokpo and Hadong Research Station were established at 2004 and at 2005 but Bosung Station was established at 1992. Seven clonal tea cultivers were selected at Bosung Station; Bohyang, Myngsun, Chanlok, Sunhyang, Mihyang, Jinhyang and Ohsun until 2004. Mokpo Experimental Institute was started the tea provenance testing about 4 provenances: Kangwon-do, Jeonlabuk-do, Jeonlanam-do, and Kyungsangnam-do. Korean new tea cultivers should be selected because Koran wild tea population have been high genetic variation. If tea breeding research will be successful to select new clonal cultivers, the tea farmers of Korea will be stable after WTO treatment with each country.

• Journal of Ecology and Environment
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• v.43 no.3
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• pp.320-331
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• 2019

Background: Dioecious plant species having both male and female plants have been investigated regarding sex-related characteristics such as sex ratio, sex-differential resource requirements, and spatial segregation of the sexes. Habitat loss and fragmentation are major threats to the survival of plant populations, but dioecious species are particularly more prone to such habitat degradation than non-dioecious species because of their dimorphic sexual system. We examined the sex-related demographics of two Ilex cornuta populations being different regarding land use history. Methods: During 2016-2017, we examined I. cornuta trees with a basal diameter ${\geq}1.5cm$ in the Yongsu-ri population (YS population) and the Gotjawal Provincial Park population (GP population). Plant sex (male, female, or unsexed) was identified. The tree size (basal diameter and height of the main stem), clonal production (the ramet numbers per genet), and vitality for each clone were measured. The associations between population, sex, tree size, clonal production, and vitality were examined using ANOVAs and contingency table analyses. Finally, point pattern analyses using O-ring statistics were conducted to assess spatial patterns. Results: Upon excluding unsexed trees, the YS population with 74 trees was significantly male-biased (0.66), while the GP population with only 26 trees had a 1:1 sex ratio. In both populations, males and females did not differ in tree size. Although the mean number of ramets differed significantly between populations, females tended to produce more ramets than males. The proportion of weak trees was significantly higher in the YS than in the GP population. Neither population showed evidence of spatial segregation of the sexes. Conclusions: The two populations of dioecious I. cornuta are characterized by the small number of trees and relatively high frequencies of non-reproductive trees. Both indicate that these populations are quite susceptible to environmental and genetic stochasticity. On the other hand, the differences between populations in sex ratio, clonal production, and vitality suggest that conservation efforts for I. cornuta need to be population-specific. In order to help recover and enable this vulnerable species to persist, it is necessary to find ways to enhance their sexual reproduction and simultaneously reduce habitat disturbances due to anthropogenic activities.

• Journal of Plant Biology
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• v.38 no.2
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• pp.173-180
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• 1995

We investigated levels and distribution of genetic variation in Korean populations of Calystegia soldanella and C. japonica, clonally reproducing herbaceous perennials. Calystegia soldanella is one ofecologically important beach plants growing only on sand and beach dunes in Europe, East Asia, the Pacific Islands, and the west coast of North America. In contrast, C. japonica usually grows on small mounds of paddy fields, roadsides, and waste places with patchy distribution. Starch gel electrophoresis was conducted on leaves collected from 13 populations of C. soldanella and eight populations of C. japonica. The levels of genetic variation of the two species are very comparable; means of expected heterozygosity (Hep) were 0.100 and 0.099 for C. soldanella and C. japonica, respectively. These values were also very similar to those for species with similar life-history and ecological traits. However, the proportion of total genetic diversity partitioned among populations (GST) of C. soldanella (0.146) was considerably lower than that of C. japonica (0.383). In addition, means of Nei's genetic identity (Ⅰ) for C. soldanella and C. japonica were 0.985 and 0.900, respectively, which supports a restricted gene flow resulting from obligate clonal reproduction of C. japonica. Significant differences in allele frequency were detected among populations at eight and nine of nine polymorphic loci for C. soldanella and C. japonica (P<0.01), respecitvely. Considering the ecological importance of C. soldanella, the isolated beach populations coupled with present destruction of natural habitats of the species may result in erosion of genetic diversity in the near future. In this respect, conservation efforts should be focused on those populations that currently maintain the most genetic diversity such as those populations in the eastern and southeastern Korean Peninsula and Hamduck Beach, Cheju Island.