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Prediction of Spring Flowering Timing in Forested Area in 2023 (산림지역에서의 2023년 봄철 꽃나무 개화시기 예측)

  • Jihee Seo;Sukyung Kim;Hyun Seok Kim;Junghwa Chun;Myoungsoo Won;Keunchang Jang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.4
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    • pp.427-435
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    • 2023
  • Changes in flowering time due to weather fluctuations impact plant growth and ecosystem dynamics. Accurate prediction of flowering timing is crucial for effective forest ecosystem management. This study uses a process-based model to predict flowering timing in 2023 for five major tree species in Korean forests. Models are developed based on nine years (2009-2017) of flowering data for Abeliophyllum distichum, Robinia pseudoacacia, Rhododendron schlippenbachii, Rhododendron yedoense f. poukhanense, and Sorbus commixta, distributed across 28 regions in the country, including mountains. Weather data from the Automatic Mountain Meteorology Observation System (AMOS) and the Korea Meteorological Administration (KMA) are utilized as inputs for the models. The Single Triangle Degree Days (STDD) and Growing Degree Days (GDD) models, known for their superior performance, are employed to predict flowering dates. Daily temperature readings at a 1 km spatial resolution are obtained by merging AMOS and KMA data. To improve prediction accuracy nationwide, random forest machine learning is used to generate region-specific correction coefficients. Applying these coefficients results in minimal prediction errors, particularly for Abeliophyllum distichum, Robinia pseudoacacia, and Rhododendron schlippenbachii, with root mean square errors (RMSEs) of 1.2, 0.6, and 1.2 days, respectively. Model performance is evaluated using ten random sampling tests per species, selecting the model with the highest R2. The models with applied correction coefficients achieve R2 values ranging from 0.07 to 0.7, except for Sorbus commixta, and exhibit a final explanatory power of 0.75-0.9. This study provides valuable insights into seasonal changes in plant phenology, aiding in identifying honey harvesting seasons affected by abnormal weather conditions, such as those of Robinia pseudoacacia. Detailed information on flowering timing for various plant species and regions enhances understanding of the climate-plant phenology relationship.

Monitoring of Bathymetry Changes in the Coastal Area of Dokdo, East Sea (동해 독도 연안 해저지형 변동 모니터링 연구)

  • Chang Hwan Kim;Soon Young Choi;Won Hyuck Kim;Hyun Ok Choi;Chan Hong Park;Yun Bae Kim;Jong Dae Do
    • Economic and Environmental Geology
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    • v.56 no.5
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    • pp.589-601
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    • 2023
  • We compare high-resolution seabed bathymetry data and seafloor backscattering data acquired, using multi-beam, between 2018 and 2021 to understand topographic changes in the coastal area of Dokdo. The study area, conducted within a 500 m × 500 m in the southern coast between the islands where Dongdo Port is located, has been greatly affected by human activities, waves and ocean currents. The depth variations exhibit between 5 - 70 m. Irregular underwater rocks are distributed in areas with a depth of 20 m or less and 30 - 40 m. As a whole, water depth ranges similar in the east-west direction and become flatter and deeper. The bathymetry contour in 2020 tends to move south as a whole compared to 2018 and 2019. The south moving of the contours in the survey area indicates that the water depth is shallower than before. Since the area where the change in the depth occurred is mainly formed of sedimentary layers, the change in the coast of Dokdo were mainly caused by the inflow of sediments, due to the influence of wind and waves caused by these typhoons (Maysak and Haishen) in 2020. In the Talus area, which developed on the shallow coast between Dongdo and Seodo, the bathymetry changed in 2020 due to erosion or sedimentation, compared to the bathymetry in 2019 and 2018. It is inferred that the changes in the seabed environment occur as the coastal area is directly affected by the typhoons. Due to the influence of the typhoons with strong southerly winds, there was a large amount of sediment inflow, and the overall tendency of the changes was to be deposited. The contours in 2021 appears to have shifted mainly northward, compared to 2020, meaning the area has eroded more than 2020. In 2020, sediments were mainly moved northward and deposited on the coast of Dokdo by the successive typhoons. On the contrary, the coast of Dokdo was eroded as these sediments moved south again in 2021. Dokdo has been largely affected by the north wind in winter, so sediments mainly move southward. But it is understood that sediments move northward when affected by strong typhoons. Such continuous coastal change monitoring and analysis results will be used as important data for longterm conservation policies in relation to topographical changes in Dokdo.

Inhibition Effects of Weisiella cibaria SPM402 and Lactobacillus paracasei SPM412 against Gingipains as a Major Virulence Factor for Porphyromonas gingivalis (Porphyromonas gingivalis의 병인인자 Gingipain 억제능을 갖는 Weisiella cibaria SPM402와 Lactobacillus paracasei SPM412)

  • Chae Hyeon Seo;Kang SoWon;Sungsook Choi
    • Journal of Food Hygiene and Safety
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    • v.38 no.6
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    • pp.544-550
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    • 2023
  • To develop a functional probiotic that inhibits gingipain, a major virulence factor of Porphyromonas gingivlais (P. gingivalis), we screened over 30 probiotic strains for their ability to inhibit gingipian activity. We investigated the inhibition of expression of gingipain genes kgp, rgpA, and rgpB as well as gingipain activity, using freeze dried cell-free supernatants of Weisiella cibaria SPM402 (WC402) and Lactobacillus paracasei SMP412 (LP412), both of which demonstrated antibacterial activity against P. gingivalis. Thus, it was verified that kgp expression was reduced by approximately 0.71±0.02 folds and rgpB expression was reduced by approximately 0.71±0.14 folds at a concentration of WC402 10 mg/mL. Meanwhile, at the same concentration of 10 mg/mL of LP412, kgp expression was reduced by approximately 0.19±0.08 folds, rgpA expression was reduced by approximately 0.09±0.02 folds, and rgpB expression was reduced by approximately 0.24±0.03 folds. At a concentration of 10 mg/mL, Kgp activity was inhibited by approximately 78.65±3.58% (cell associated gingipain, CAG), 82.45±1.22% (cell-free gingipain, CFG) by WC402 and 80.71±2.11% (CAG), and 85.81±0.05% (CFG) by LP412 respectively. Rgp activity was also effectively inhibited by approximately 78.6±1.01% (CAG), 86.78±0.47% (CFG) and 82.93±1.26% (CAG), 88.81±0.36% (CFG) by WC402 and LP412 respectively. Based on these results, W. cibaria SPM402 and L. paracasei SPM412 can be regarded as functional probiotics with the ability to inhibit gingipain activity and exhibit antibacterial effects against P. gingivalis.

A Study on Moral Systems of Aristotle and Kang Jeungsan: Focusing on the Nature of Virtue and Teleological Characteristics (아리스토텔레스와 강증산(姜甑山) 성사(聖師)의 덕(德)이론 고찰 -덕의 속성 및 목적성과 관련하여-)

  • Joo So-yeon;Ko Nam-sik
    • Journal of the Daesoon Academy of Sciences
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    • v.46
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    • pp.189-234
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    • 2023
  • The most common and prevailing system of virtue ethics is based around the idea of personality rather than external behavior and it grew out of the Aristotelian system of virtue ethics. The purpose of this study is to find out the characteristics of the virtue ethics found within Daesoon Thought through comparison to Aristotelian virtue ethics. This can serve as a basis to establish the virtue ethics of Daesoon Thought in further studies. The systems of virtue ethics posited by the two traditions are similar in that they are both teleological as the virtues they recognize are related to human nature in the context of certain metaphysical assumption and they both exhibit the characteristic tendencies of seeking to realize the highest human good. Therefore, in the Aristotelian context, virtues can be defined as "characteristics needed for the realization of eudaimonia," and for Daesoon Thought, virtues are "characteristics needed for the realization of the Resolution of Grievances for Mutual Beneficence." The representative virtues examined in this comparative study will be the Aristotelian Golden Mean, and the the concepts of guarding against self-deception and great benevolence and great justice in Daesoon Thought. In comparison to Aristotelian virtues, these differ in three main ways. First, Aristotelian virtue is not an innate aspect of character the way it is assumed to be in Daesoon Thought wherein the original human heart bestowed by Heaven is already virtuous. Second, mental virtue in the Aristotelian context centers the mind upon reason whereas in Daesoon Thought, the heart-mind exhibits both reason and emotional concern for others. Third, eudaimonia is a concept limited to humans and their societies whereas the Resolution of Grievances for Mutual Beneficence is a good that includes all beings including divine beings, animals, plants, and Heaven and Earth. Despite the differences, both require practical reason, continuous education, and effort to succeed in the cultivation of virtues and the proper implementation of virtuous living.

Preliminary Study on the Genesis and Nickel Potential of Ultramafic Rocks in Chungnam Yugu area, South Korea (충남 유구지역 초염기성암의 성인과 니켈 잠재성에 대한 예비연구)

  • Ijeung Kim;Sang-Mo Koh;Otgon-Erdene Davaasuren;Gi Moon Ahn;Chul-Ho Heo;Bum Han Lee
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.4
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    • pp.323-336
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    • 2023
  • We investigated the nickel potential and genesis of ultramafic rocks in the Yugu area to secure nickel resources in South Korea. The Yugu ultramafic rocks, located in the southwest of the Gyeonggi Massif, are characterized by spinel peridotite and exhibit strong serpentinization along their boundaries. The serpentinization is observed as olivine transformed to antigorite and chrysotile, while pentlandite, the nickel sulfide mineral, altered into millerite and awaruite. Serpentine displays distinct foliation, aligning subparallel to the ultramafic rock boundaries and foliation of Yugu gneiss. This suggests that the uplift of ultramafic rocks resulted in hydrothermal infiltration likely sourced from the Yugu gneiss metamorphism. The Yugu ultramafic rocks are residues after 5~18% partial melting of abyssal peridotite. Enriched light rare earth elements and Eu imply secondary metasomatism. Geochemistry suggests a link between the formation of Yugu ultramafic rock and the Triassic collision of the North and South China continents. The nickel content is around 0.17~0.21%, mainly contained in olivine and serpentine. Hence, in addition to the mineral processing study on the sulfide minerals, focused studies on oxide minerals for enhanced nickel recovery within the Yugu ultramafic rock are strongly suggested.

Comparison of Agrobacterium-mediated Transformation Efficiency in 43 Korean Wheat Cultivars (국내 밀 43개 품종에 대한 아그로박테리움 형질전환 효율성 검정)

  • Jae Yoon Kim;Geon Hee Lee;Ha Neul Lee;Do Yoon Hyun
    • Journal of Practical Agriculture & Fisheries Research
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    • v.25 no.4
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    • pp.138-147
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    • 2024
  • Agrobacterium-mediated transformation (AMT) is a method that allows for the stable integration of DNA fragments into the plant genome. Transgenic plants generated through AMT typically exhibit a lower copy number of the transgene compared to those induced by particle bombardment. Furthermore, AMT offers a straightforward and efficient approach for generating transgenic plants. While the transformation efficiency of wheat is comparatively lower than that of other monocot plants such as Rice (Oryza sativa L.) and Maize (Zea mays L.), the cultivars 'Bobwhites' and 'Fielder' are commonly employed for wheat transformation. To date, there have been no reported instances of successful development of transgenic plants using Korean wheat varieties through AMT. This study aims to assess the transformation efficiency of 43 Korean wheat cultivars using the GUS assay, with the goal of identifying suitable Korean wheat cultivars for AMT. The pCAMBIA1301 vector, carrying the β-glucuronidase (GUS) gene, was incorporated into Agrobacterium strain EH105. Following the inoculation of Agrobacterium into immature embryos, GUS assays were conducted 'Saeol', 'Jopum', and 'Jonong' showed 100% (the number of embryos showing GUS spots/the number of embryos used for AMT) among 43 cultivars. In addition, cultivars with more than 70% were 'Saekeumgang', 'Jojung', 'Tapdong', 'Anbaek', 'Dabun', 'Sugang', 'Keumgang', 'Jeokjung', 'Seodun', 'Joeun', 'Dajung', and 'Baekjung'. It seems that the 15 cultivars above showed the possibility of using AMT. On the other hand, 'Yeonbaek', 'Goso', 'Baekgang', and 'Johan' showed less than 20% and GUS spots were not observed in 'Gru', 'Gobun', 'Milseong', and 'Shinmichal-1'. This study explores transient GUS expression in Korean wheat cultivars seven days after AMT. The observed initial high efficiency of transient transformation suggests the potential for subsequent stable transformation efficiency. Korean wheat cultivars demonstrating elevated transient transformation efficiency could serve as promising candidates for the development of stable transgenic wheat.

A Comparative Study on Factors Affecting Satisfaction by Travel Purpose for Urban Demand Response Transport Service: Focusing on Sejong Shucle (도심형 수요응답 교통서비스의 통행목적별 만족도 영향요인 비교연구: 세종특별자치시 셔클(Shucle)을 중심으로)

  • Wonchul Kim;Woo Jin Han;Juntae Park
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.2
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    • pp.132-141
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    • 2024
  • In this study, the differences in user satisfaction and the variables influencing the satisfaction with demand response transport (DRT) by travel purpose were compared. The purpose of DRT travel was divided into commuting/school and shopping/leisure travel. A survey conducted on 'Shucle' users in Sejong City was used for the analysis and the least absolute shrinkage and selection operator (LASSO) regression analysis was applied to minimize the overfitting problems of the multilinear model. The results of the analysis confirmed the possibility that the introduction of the DRT service could eliminate the blind spot in the existing public transportation, reduce the use of private cars, encourage low-carbon and public transportation revitalization policies, and provide optimal transportation services to people who exhibit intermittent travel behaviors (e.g., elderly people, housewives, etc.). In addition, factors such as the waiting time after calling a DRT, travel time after boarding the DRT, convenience of using the DRT app, punctuality of expected departure/arrival time, and location of pickup and drop-off points were the common factors that positively influenced the satisfaction of users of the DRT services during their commuting/school and shopping/leisure travel. Meanwhile, the method of transfer to other transport modes was found to affect satisfaction only in the case of commuting/school travel, but not in the case of shopping/leisure travel. To activate the DRT service, it is necessary to consider the five influencing factors analyzed above. In addition, the differentiating factors between commuting/school and shopping/leisure travel were also identified. In the case of commuting/school travel, people value time and consider it to be important, so it is necessary to promote the convenience of transfer to other transport modes to reduce the total travel time. Regarding shopping/leisure travel, it is necessary to consider ways to create a facility that allows users to easily and conveniently designate the location of the pickup and drop-off point.

The Great Opening of the Later World in Daesoon Thought and the World of Pre-experientialism from the Reordering Works of Heaven and Earth as Understood in Yi-Jing Studies (천지개벽의 역학적 사유에서 본 대순사상의 후천개벽과 선험주의적 세계)

  • Kim Yon-jae
    • Journal of the Daesoon Academy of Sciences
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    • v.47
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    • pp.1-37
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    • 2023
  • This essay seeks to answer the question of how best to understand Korean new religious movements (KNRMs). KNRMs have the characteristics of folk religion, ethno-religion, or popular religion. KNRMs are products of the national consciousness promoted by Korean society during the Late Joseon Dynasty at the turning point of modern Yi-Jing Studies. From the perspective of social evolutionary theory of developmental history, during that period, Joseon (Korea), like China, was faced with a double-edged sword consisting of the strength of tradition and the upheaval of modernity. If the strength of tradition depended on the Yi-Jing Studies to promote national enlightenment toward anti-imperialist aims, then it was equally the case that modernity depended on the sense of urgency to guide the people to secure livelihoods and edification regarding anti-feudalism. In this essay, the KNRMs that appeared during this transition period of Yi-Jing Studies will be a significant focus, and the worldview of Daesoon Thought will be the main focus. As one of the central topics, intensive discussion will be dedicated to the issue of the nature of pre-experientialism (先驗主義) which characterized the Great Opening (開闢). The principles of Daesoon Thought have a religious dimension of realistic awareness that guides the people's lives and edifies them. The process of the Great Opening aims to secure an ontological clock that tracks the Great Itineration of the world toward Daesoon Truth. This in turn as a process establishes the epistemological world of the Reordering Works of Heaven and Earth (天地公事) and reaches the axiological boundary of the future world. The links among the Three Realms is characterized by a pre-experientialist line that experiences the space-time nature of the universe as the Great Opening of the Later World (後天) within the framework of Heaven and Earth. Throughout this course, humans look to enjoy the infinite vitality of the universe from within their own finite vitality. Therefore, Daesoon Thought can overcome perceived reality through pre-experientialist channels such as the Great Opening of the Later World and aim for a state of self-awareness such as the Earthly Paradise. This is an attempt to participate and practice in the actual world rather than pursuing a world of transcendental ideas, and therefore, it tends to be proactive in the world rather than exhibit a passive tendency to be worldliness. In conclusion, the truth of Daesoon Thought, which is characterized by the Great Opening of the Later World, contains a future-oriented outlook that longs for a Nextopia full of hope and promise rather than idealistic fancy towards a Utopia or well-founded dread and disdain towards Dystopia.

Microbiological and Enzymological Studies on the Flavor Components of Sea Food Pickles (젓갈등속(等屬)의 정미성분(呈味成分)에 관(關)한 미생물학적(微生物學的) 및 효소학적(酵素學的) 연구(硏究))

  • Lee, Ke-Ho
    • Applied Biological Chemistry
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    • v.11
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    • pp.1-27
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    • 1969
  • More than thirty kinds of sea food pickles have been eaten in Korea. Out of these salted yellow tail pickle, salted clam pickle, salted oyster pickle, and salted cuttlefish pickle were employed for the analysis of their components, identification of main fermenting microbes, and determination of enzyme characteristics concerned. Also studied was the effect of enzymic action of microbes, which are concerned with the fermenting of pickles, on the production of flavorous 5'-mononucleotides and amino acids. The results are summarized as follows: 1. Microflora observed in the pickles are: (a) Total count of viable cells after 1-2 months of pickling was found to be $10^7$ and that after 6 months decreased to $10^4$. (b) Microbial occurence in the early stage of pickling was observed to be 10-20% Micrococcus spp., 10-20% Brevibacterium spp., 0-30% Sarcina spp., 20-30% Leuconostoc spp., ca 30% Bacillus spp., 0-10% Pseudomonas spp., 0-10% Flavobacterium spp., and 0-20% yeast. (c) Following the early stage of pickling, mainly halophilic bacteria such as Bacillus subtilis, Leuconostoc mesenteroides, Pediococcus halophilus and Sarcina litoralis, were found to exhibit an effect on the fermentation of pickle and their enzyme activities were in direct concern in fermentation of pickles. (d) Among the bacteria participating in the fermentation, Sarcina litoralis 8-14 and 8-16 strains were in need of high nutritional requirement and the former was grown only in the presence of purine, pyrimidine and cystine and the latter purine, pyrimidine and glutamic acid. 2. Enzyme characteristics studied in relation to the raw materials and the concerned microbes isolated are as follows: (a) A small amount of protease was found in the raw materials and 30-60% decrease in protease activity was demonstrated at 7% salt concentration. (b) Protease activity of halophilic bacteria, Bacillus subtilis 7-6, 11-1, 3-6 and 9-4 strains, in the complete media decreased by 10-30% at the 7% salt concentration and that of Sarcina litoralis 8-14 and 8-16 strains decreased by 10-20%. (c) Proteins in the raw materials were found to be hydrolyzed to yield free amino acids by protease in the fermenting microbes. (d) No accumulation of flavorous 5'-mononucleotides was demonstrated because RNA-depolymerase in the raw materials and the pickles tended to decompose RNA into nucleoside and phosphoric acid. (e) The enzyme produced in Bacillus subtilis 3-6 strain isolated from the salted clam pickles, was ascertained to be 5'-phosphodiesterase because of its ability to decompose RNA and thus accumulating 5'-mononucleotide. (f) It was demonstrated that the activity of phosphodiesterase in Bacillus subtilis 3-6 strain was enhanced by some components in the corn steep liquor and salted clam pickle. The enzyme activity was found to decrease by 10-30% and 40-60% at the salt concentration of 10% and 20%, respectively. 3. Quantitative data for free amino acids in the pickles are as follows: (a) Amounts of acidic amino acids such as glutamic and aspartic acids in salted clam pickle, were observed to be 2-10 times other pickles and it is considered that the abundance in these amino acids may contribute significantly to the specific flavor of this food. (b) Large amounts of basic amino acids such as arginine and histidine were found to occur in salted yellow tail pickle. (c) It is much interesting that in the salted cuttlefish pickle the contents of sulfur-containing amino acids were exceedingly high compared with those of others: cystine was found to be 17-130 times and methionine, 7-19 times. (d) In the salted oyster pickle a high content of some essential amino acids such as lysine, threonine, isoleucine and leucine, was demonstrated and a specific flavor of the pickle was ascribed to the sweet amino acids. Contents of alanine and glycine in the salted oyster pickle were 4 and 3-14 times as much as those of the others respectively. 4. Analytical data for 5'-mononucleotides in the pickles are as follows: (a) 5'-Adenylic acid and 3'-adenylic acid were found in large amounts in the salted yellow tail pickle and 5'-inosinic acid in lesser amount. (b) 5'-Adenylic acid, especially 3'-adenylic acid predominated in amount in the salted oyster pickle over that in the other pickles. (c) The salted cuttlefish pickle was found to contain only 5'-adenylic acid and 3'-adenylic acid. It has become evident from the above fact that clam and the invertebrate lack of adenylic deaminase and contain high content of adenylic acid. Thus, they were demonstrated to be the AMP-type. (d) 5'-Inosinic acid was contained in the salted yellow tail pickle in a significant concentration, and it might be considered to be IMP-type. 5. Comparative data for flavor with regard to the flavorous amino acids and the contents of 5'-mononucleotides are: (a) A specific flavor of salted yellow tail pickle was ascribed to the abundance in glutamic acid and aspartic acid, and to the existence of a small amount of flavorous 5'-inosinic acid. The combined effect of these components was belived to exhibit a synergistic action in producing a specific fiavor to the pickle. (b) A specific flavor of salted clam pickle has been demonstrated to be attributable to the richness in glutamic acid and aspartic acid rather than to that of 5'-mononucleotides.

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Studies on the Species Crossabilities in the Genus Pinus and Principal Characteristics of F1 Hybrids (일대잡종송(一代雜種松)의 교배친화력(交配親和力)과 특성(特性)에 관(關)한 연구(硏究))

  • Ahn, Kun Yong
    • Journal of Korean Society of Forest Science
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    • v.16 no.1
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    • pp.1-32
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    • 1972
  • By means of the interspecific hybridization in the Sub-genus Diploxylon of the Genus Pinus, $F_1$ hybrids of Pinus rigida${\times}$elliottii, Pinus rigida${\times}$radiata, P. rigida${\times}$serotina and P. densiflora${\times}$thunbergii had been produced. And on the basis of the crossabilities of these hybrids the taxonomic affinities of these pines were examined. And the needle characteristics of these hybrid and the occurence of phenolic substances in these $F_1$ hybrid were also investigated to see the potential usefulness of these characteristics for the diagnosis of the taxonomic affinity. And, the growth performances of the $F_1$ hybrids have also been compared with those of parental species. In order to contribute to the establishment of the hybrid seed orchard the introgression phenomena between P. densiflora and P. thunbergii in the eastern coastal area have also been investigated along with the investigation of the heterozygosity of plus trees of P. densiflora growing in the clone bank in Suwon. And the results were summarized as follows. 1. On the basis of crossabilities as well as on the taxonomic affinities according to the systems of Shaw, Pilger and Duffield, it has been proven that the parental species of those hybrids are of close affinities and range of the fertile hybrid seed production rate was as high as 28-58% in the best hybrid combination (Table 13). 2. Among those hybrids, the ${\times}$ Pinus, rigiserotina hybrid seemed to be most promising in the growth performance exhibiting 109-155% more volume growth compared to the seed parent with the statistic significance of 1% level (Tables 16 and 17). 3. Notwithstanding the fact that the all of the pollen parents are cold tender, all hybrids exhibit cold hardiness as much as their seed parent and it seems to suggest that the characteristics of cold hardiness were transmitted from the seed parent. 4. Though a striking difference in needle length was observed between the parental species of each hybrid, it was difficult to distinguish each hybrid from their seed parent by the needle length except ${\times}$P. rigiserotina which is characterized by long needle which is 65% more longer than the needle of the seed parent (Table 21). 5. With regard to the anatomical characteristics of needle, the hypoderm is apparently thicker in most of the $F_1$ hybrid pines and the characteristics of resin canals are dominated by medial in most $F_1$ hybrid. And, the fibrovascular bundles were apart as were in their seed parent. Therefore it was found to be possible to distinguish the hybrids pines from their parents by the needle characteristics. And, it is to be noticed that the ${\times}$P. densithunbergii was more close to the pollen parent having RDI value of 0.73 (Fig.l, Table 22). 6. It has been demonstrated that ${\times}$P. rigielliottii, ${\times}$P. rigiradiata and ${\times}$P. rigitaeda have a phenolic substance (No.7) of light yellow at Rf-0.46, same as their seed parent, but no trace of phenolic substance was observed in their pollen parent. This fact will serve as an important criteria for early identification of hybridity in progeny testing. However, the fact that both of ${\times}$P. rigiserotina and ${\times}$P. densithunbergii exhibit the same reactions of phenolic substances as well their parental species seems to indicate the close affinities between the parental species of the respective hybrid (Fig.2, Table 23). 7. The separation and the reaction of phenolic substance developed on TLC were found to be same in the same species showing no variations between the individuals, and no variations due to tree part of sampling, tree age or pollen sources. And the reaction was also observed regardless of the not varied by the kind of developing solvent whether it is Aceton-Chloroform (3:7 v/v) or Benzene-Methanol-Acetic acid (90:16:8 v/v). 8. The introgression phenomena of natural Pinus densifiora stand in both east and west coastal area indicates that the major part of the red pines investigated are all heterozygous and the heterozygosity of pines are higher in the west coast than in the east coast(Tables 24 and 25). 9. Based on the RDI, among the plus trees of Pinus densiflora selected in Korea and Japan as well, no pure P. densiflora has been found. Since all of the sample trees of Pinus densiflora were found to be as heterozygous bearing part of the characteristics of P. thunbergii, those red pines were considered to be natural heterotic hybrid pines(Figs. 3 and 4. Tables 26 and 27).

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