• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.282-282
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• 2005

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.283-283
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• 2005

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.164-171
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• 2005

Codium fragile (Suringar) Hariot, an edible green alga is farmed in Korea by natural blooming zygotes attachment. Experiments were conducted to reveal the conditions for artificial seed production of C. fragile by sexual and asexual reproduction. Growth was compared between zygotes attachment (sexual reproduction) and isolated utricles with medullary filaments (asexual reproduction). Zygotes and isolated utricles with medullary filaments were cultured under different light conditions (10, 20, 40, 60 and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and temperatures (5, 10, 15, 20 and $25^{\circ}C$) under 16:8LD. Maximum growth of zygote was $261.3{\pm}21.0\;{\mu}m$ under $15^{\circ}C$ and $20\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 13 days culture. Maximum regeneration of isolated medullary filament was $8.1{\pm}1.7\;mm$ per one isolated utricle under $20^{\circ}C$ and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 15 days culture. After intermediate culture during two months in the field, morphogenesis occurred in both sexual and asexual reproduction, and growth of young thalli was not significantly different (p>0.05) between the both reproduction methods. Even though seed production of C. fragile is possible in both sexual and asexual reproduction, the mass artificial seed production of asexual reproduction is much more effective than that of sexual reproduction that is too much affected by maturity.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.236-244
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• 2014

The plant pathogen Fusarium graminearum causes Fusarium head blight in cereal crops and produces mycotoxins that are harmful to animals and humans. For the initiation and spread of disease, asexual and sexual reproduction is required. Therefore, studies on fungal reproduction contribute to the development of new methods to control and maintain the fungal population. Screening a previously generated transcription factor mutant collection, we identified one putative $C_2H_2$ zincfinger transcription factor, pcs1, which is required for both sexual and asexual reproduction. Deleting pcs1 in F. graminearum resulted in a dramatic reduction in conidial production and a complete loss of sexual reproduction. The pathways and gene ontology of pcs1-dependent genes from microarray experiments showed that several G-protein related pathways, oxidase activity, ribosome biogenesis, and RNA binding and processing were highly enriched, suggesting that pcs1 is involved in several different biological processes. Further, overexpression of pcs1 increased conidial production and resulted in earlier maturation of ascospores compared to the wild-type strain. Additionally, the vegetative growth of the overexpression mutants was decreased in nutrient-rich conditions but was not different from the wild-type strain in nutrient-poor conditions. Overall, we discovered that the pcs1 transcription factor positively regulates both conidiation and sexual reproduction and confers nutrient condition-dependent vegetative growth.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.19-26
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• 2017

Rapid progress in epigenetic studies has resulted in genome wide information of genetic functions, other than DNA sequence information. However, insufficient understanding and unclear research direction in epigenetics has failed to attract many researchers. Here, we review the sexual reproduction processes that are particularly related to epigenetics in plants. We aim to elucidate the roles of epigenetic information and molecular mechanisms involved in the complex sexual reproduction process of plants, and examine their biological significance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.62-67
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• 2019

We studied the effect of several sex-related steroid hormones (serotonin, progesterone and ${\beta}$-estradiol) for 6 days on the induction of sexual reproduction for the mass production of resting eggs in the marine rotifer Brachionus rotundiformis. The highest mix rate of 20.6% appeared with the ${\beta}$-estradiol ($E_2$) treatment on the third day. The number of resting eggs was highest with $E_2$ treatment, followed by that of the serotonin treatment group. In addition, we investigated the effect of the hormones on the expression pattern of the genes related to sexual reproduction in the rotifer. NrbP, SRY, Cyclin and MrpmB genes were up-regulated with all the hormone treatments. As a result, ${\beta}$-estradiol was more effective than the other hormone treatments to produce resting eggs in B. rotundiformis. We suggest that the sexual reproduction-related genes in the rotifer are the NrbP, SRY, Cyclin and MrpmB genes. Further study is required to determine the optimum concentration of $E_2$ for the effective production of resting eggs in the rotifer.

• Animal cells and systems
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• v.12 no.4
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• pp.231-240
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• 2008

The gorgonian coral Anthoplexaura dimorpha Kukenthal, 1908(Gorgonacea: Octocorallia) is abundant in Jejudo Islands, Korea. To investigate the sexual reproduction of this species, we surveyed the morphology and cycle of gametogenesis. 5-6cm long fragments from 3-7 randomly chosen colonies were collected monthly at a depth of 12-24m in the water surrounding Munseom from August 2003 to August 2005. This species was gonochoric with sex ratio of 1.86:1(female to male), and had one annual reproductive cycle affected by elevation of seawater temperature. Oogenesis was longer than spermatogenesis as 12 months in female and 6 months in male. The planulae were not observed from the field survey and histological sections, which suggested broadcast spawning for the reproductive mode in this species. The possible spawning events may occur after the seawater temperature attain to the annual peak in September.

• Journal of Ecology and Environment
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• v.37 no.1
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• pp.21-29
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• 2014

Robinia pseudoacacia has become invasively naturalized in Japan. We investigated the role of sexual reproduction in the development of R. pseudoacacia riparian forests along the Chikumagawa River in Japan, by using five chloroplast (cpSSR) and seven nuclear (nSSR) markers. We identified eight chloroplast haplotypes and 147 nuclear genotypes from 619 R. pseudoacacia trees sampled in three plots (Plots A, B, and C) and along two line transects (Lines D and E). CpSSR analyses showed that multiple maternal lines were distributed along the river, and that some haplotypes from different populations overlapped. In addition, while Plots A and B were separated by a short distance, only these two plots exhibited genetic differentiation in the haplotypes. In the nSSR analysis, all pairwise $F_{ST}$ values among the three plots were significantly different from zero. Kinship analysis based on nSSR markers revealed that kinship connected many individuals to another individual from the same plot. These results indicate that seed dispersal near to mother trees contributes to the fine-scale genetic structure of R. pseudoacacia riparian forests. Our results indicate that sexual reproduction, in addition to asexual reproduction, is a major contributor to the fine-scale formation of R. pseudoacacia forests.

• Korean Journal of Animal Reproduction
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• v.11 no.3
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• pp.151-154
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• 1987

Of the 1153 culling sows, the most important cause was the reproductive disorders (38.6%), followed by lameness and arthritis (23.3%), metabolic diseases (9.1%), agalactia (8.9%) and advancing age (7.7%). Of 840 culled sows, 173 sows showed pathological changes in the sexual organs. The uteral changes was found in 56.1% of cases, uteral and ovarian changes in 26.6%, ovarian changes in 14.4% and vaginal changes in 2.9%.