This study was carried out to investigate the flora of Jingangsan Mt. (Ganghwa-gun). The vascular plants identified during the 11 round field surveys were a to total of 560 taxa: 114 families, 336 genera, 495 species, 7 subspecies, 53 varieties, 4 forms and 1 hybrid. A high plant diversity were Poaceae (11.0%), Asteraceae (10.8%), Cyperaceae (8.8%), Rosaceae (4.6%) and Lamiaceae (4.3%) in regular order. The four taxa of Korean endemic plants such as Viola seoulensis Nakai, Salix koriyanagi Kimura ex Goerz, Hemerocallis hakuunensis Nakai and Polygonatum infundiflorum Y. S. Kim, B. U. Oh & C. G. Jang were collected. The vascular plants on the red list according to IUCN evaluation basis were found to be four taxa: Near Threatened (NT) species of Delphinium maackianum Regel, and Not Evaluate (NE) species of Mosla japonica (Benth. ex Oliv.) Maxim., Carex paxii Kük. and Polygonatum infundiflorum Y. S. Kim, B. U. Oh & C. G. Jang. The floristic regional indicator plants found in this area were 28 taxa comprising two taxa of degree Ⅳ, three taxa of degree Ⅲ, eight taxa of degree Ⅱ, and 15 taxa of degreeⅠ. In addition, the naturalized plants were identified as 44 taxa and the percentage of naturalized index (NI) was 7.9%, and Urbanization Index (UI) was 13.7%.

Neurokinin B (NKB) and neurokinin B related peptide (NKBRP) belong to tachykinin peptide family. They act as a neurotransmitter and/or neuromodulator. Mutation of NKB and/or its cognate receptor, NK3R resulted in hypogonadotropic hypogonadism in mammals, implying a strong involvement of NKB/NK3R system in controlling mammalian reproduction. Teleosts possess NKBRP as well as NKB, but their roles in fish reproduction need to be clarified. In this study, NKB and NKBRP coding gene (tac3) was cloned from Nile tilapia and sequenced. Based on the sequence, Nile tilapia NKB and NKBRP peptide were synthesized and their biological potencies were tested in vitro pituitary culture. The synthetic NKBRP showed direct inhibitory effect on the expression of GTH subunits at the pituitary level. This inhibitory effect was confirmed in vivo by means of intraperitoneal (ip) injection of synthetic NKB and NKBRP to mature female tilapia (20 pmol/g body weight [BW]). Both NKB and NKBRP had no effect on the plasma level of sex steroids, E2 and 11-KT. However, NKBRP caused declines of expression level of GnRH I, Kiss2 and tac3 mRNAs in the brain while NKB seemed to have no distinct effect. These results indicate some inhibitory roles of NKBRP in reproduction of mature female Nile tilapia, although their exact functions are not clear at the moment.

Red spotted grouper, Epinephelus akaara is a popular aquaculture species in many Asian countries. This species is a protogynous hermaphrodite that first differentiates into female and changes to male later. Due to this reproductive characteristic, stable supply of male and female gametes is a key to the success of seed production in this species. Thus, understanding early gonadal differentiation is required to develop effective sex control techniques. Red spotted grouper were reared in indoor tanks and sampled every 5 days from 40 days post-hatch (DPH) to 130 DPH. Changes of gonadal tissues were examined and analyzed by means of histology. A pair of gonadal primordium has already existed underneath the kidney in the posterior part of the body cavity at 38 DPH when this study began. Gonadal primordia of 38, 40 DPH consisted of germ cells surrounded by a few somatic cells. The blood vessel was observed in the gonadal primordium at 45 DPH. The number of somatic cells and size of gonadal primordium increased age-dependently up to 60 DPH. Formation of ovarian cavity was obvious by two protuberant aggregations of somatic cells at 65 DPH. Completed ovarian cavity and oogonia were first observed in the gonad of one fish sample at 105 DPH. Based on these histological observations, it can be suggested that induction of primary male differentiation could be more successfully applied at around 60 DPH in this species.

Red spotted grouper (Epinephelus akaara) is one of the most popular and important grouper species for aquaculture in South-East and East Asia thanks to its fast growth and high market value. This species is known as a protogynous hermaphrodite which first differentiates into females and changes to males later. Natural sex change in this species occurs at 2 or 3 years of age. Many studies have been conducted, so far, to develop standardized methods for artificial sex reversal by treatment with sex steroid hormones (Bhandari et al., 2005; Lee et al., 2014). However, sex-changed male groupers showed testes with ovarian cavity, and their sperm production was very low. Induction of primary sex differentiation directly into males would be an alternative approach. Identification of the exact primary sex differentiation period is the prerequisite for this approach. Red spotted grouper were reared in indoor tanks and acclimatized at 25±2℃ under natural photoperiod. Fish were sampled at 60 days after hatching. The samples were processed for histological analysis using standard techniques in an automatic tissue processor, sectioned at 8 μm in thickness and stained with haematoxylin and eosin. The result of this study shows the morphological characteristics of gonadal primordium, and suggests that the timing of gonadal differentiation in red spotted grouper is at least 10 days earlier than the previous study of Lee et al. (2014) which observed gonadal primordium at 70 days after hatching.

This study was carried out to investigate the flora of Mt. Byeollipsan (Ganghwa-gun). The vascular plants from 13 field surveys were revealed to total of 574 taxa; 116 families, 355 genera, 505 species, 8 subspecies, 52 varieties, 7 forms and 2 hybrids. A high plant diversity were Asteraceae (12.3%), Poaceae (10.6%), Cyperaceae (6.1%), Fabaceae (4.5%) and Rosaceae (4.2%) in regular order. The seven taxa of Korean endemic plants such as Clematis brachyura, Viola seoulensis, Populus × tomentiglandulosa, Salix koriyanagi, Ajuga multiflora f. rosea, Hemerocallis hakuunensis and Polygonatum infundiflorum were collected. The red data of vascular plants according to IUCN valuation basis were examined five taxa; Least Concern (LC) species of both Phacelurus latifolius and Belamcanda chinensis, Not Evaluate (NE) species of Lithospermum arvense, Scorzonera austriaca ssp. glabra and Polygonatum infundiflorum. The floristic regional indicator plants found in this area were 34 taxa comprising one taxa of degree IV, six taxa of degree III, 11 taxa of degree II, and 16 taxa of degree I. In addition, the naturalized plants were identified as 46 taxa and the percent of naturalized index (NI) was 8.0%, Urbanization Index (UI) was 14.3%, respectively.

본 연구는 폴리비닐 알코올 섬유 및 강섬유를 체적비율로 1.5% 혼입한 고인성 섬유보강 시멘트복합체에 대한 비상체의 고속충돌시험을 실시하고, 충돌조건에 따른 파괴특성을 실험적으로 검토하는 것을 목적으로 하였다. 비상체의 충돌에 의한 고인성 섬유보강 시멘트복합체의 파괴특성을 평가하기 위하여 화약압력식 충격시험장치를 활용하였으며, 충돌속도의 범위는 약 150 ~ 1,000m/s로 설정하였다. 파괴특성에 대한 평가결과, 고인성 섬유보강 시멘트복합체는 섬유를 혼입하지 않은 Plain시험체의 약 3배 이상의 비상체 운동에너지가 작용하는 범위에서도 표면관입의 파괴등급으로 평가되었으며, 시험체가 파단되지 않는 내충격성능이 확인 되었다. 또한, 충돌시험 전후에 대한 시험체의 질량감소율의 경우, Plain시험체는 비상체의 운동에너지의 증가율과 비례적인 관계를 보였지만, 고인성 섬유보강 시멘트복합체는 비상체의 운동에너지의 영향을 크게 받지 않는 것으로 나타났다. 특히, 이와 같은 경향은 시험체 배면의 파괴특성과 밀접한 관계를 가지며, S시험체에 비해 PVA시험체의 배면박리 억제효율이 큰 것으로 평가되었다. 한편, 국부손상에 대한 표면관입깊이 및 배면박리깊이의 관계를 검토한 결과, 고인성 섬유보강 시멘트복합체는 Plain과 달리 시험체 단면의 중앙선을 기준으로 배면에 가까운 영역에서 배면박리가 발생하는 것을 알 수 있었다. 본 연구를 통해 비상체의 충돌에 대한 고인성 섬유보강 시멘트복합체의 주요 파괴거동이 검토되었으며, Plain과 비교하여 내충격성능의 향상을 명확히 확인하였다.

본 연구에서는 섬유종류에 따른 인발특성과 섬유보강 콘크리트의 휨특성에 대하여 평가하기 위하여, 섬유의 재질 및 형상 다른 후크형강섬유, 비정질 강섬유 및 폴리아미드 섬유에 대하여 인발시험과 섬유보강 콘크리트 시험체를 제작하여 휨특성을 평가하였다. 그 결과, 후크형 강섬유의 경우 최대인발하중에서 섬유가 매트릭스로부터 인발되었지만, 비정질 강섬유는 섬유와 매트릭스의 부착강도가 섬유자체의인장강도보다 높아 섬유가 매트릭스로부터 인발되지 않고 파괴되는 현상을 나타내었다, 한편, 폴리아미드 섬유는 연신율에 의해 최대인발하중까지 변위가 크게 발생하였으며, 최대하중이후에 섬유가 끊어지는 파괴특성을 나타내었다. 섬유보강 콘크리트의 휨특성에 있어서 비정질 강섬유는 매트릭스와의 부착강도가 높고, 섬유의 혼입개체수가 많아 콘크리트의 최대휨강도는 높았지만, 균열발생 이후 섬유가 매트릭스로부터 인발되지 않고 섬유가 파괴되는 것에 의해 응력의 저하가 급격하게 발생하지만, 후크형 강섬유보강 콘크리트는 균열발생 이후 섬유가 인발되면서 응력의 저하가 완만하게 발생하였다. 폴리아미드 섬유보강 콘크리트는 균열발생이후 섬유의 연신률에 의해 응력이 급격하게 저하하는 구간이 발생하였으며, 섬유와 매트릭스의 부착에 의해 재상승하였다가 섬유가 끊어지면서 파괴되었다. 섬유와 매트릭스의 인발특성은 섬유보강 콘크리트의 휨강도 및 변형 능력에 큰 영향을 미치는 것으로 판단된다.

This study was carried out to investigate the flora of indigenous habitat of Donghae-si and Samcheok-si in Gangwon-do, Korea. The vascular plants were collected 18 times (from March to October 2011), and were identified as 804 taxa; 127 families, 445 genera, 720 species, 8 subspecies, 69 varieties, 5 forms and 2 hybrids. In the flora of this area, the calcicolous plants were 55 taxa; Cheilanthes argentea, Clematis serratifoliam, Quercus variabilis. Epipactis papillosa, etc. The endangered plants designated and protected by the wildlife protection law, the Ministry of Environment, Korean were counted to one taxon; Cymbidium macrorhizum. The red list of vascular plants according to IUCN valuation basis were examined, endangered species (EN); Prunus yedoensis and Cymbidium macrorhizum, Vulnerable species (VU); Juniperus chinensis, Pulsatilla tongkangensis, Diarthron linifolium and Swertia wilfordii, Near Threatened species (NT); Paeonia japonica, Allium senescens, Epipactis papillosa and Pogonia minor, Least Concern species (LC); Asplenium ruta-muraria, Platycladus orientalis, Monotropa hypopithys and Eleutherococcus divaricatus var. chiisanensis, etc., Data Deficient species (DD); Paeonia lactiflora var. trichocarpa, and Not Evaluate species (NE); Prunus choreiana, Panax ginseng and Polygonatum infundiflorum etc. Korean endemic plants of this area were 26 taxa; Aconitum pseudolaeve, Corydalis hirtipes, Vicia chosenensis, Salvia chanroenica and Hemerocallis hakuunensis, etc. The floristic regional indicator plants found in this area were 130 taxa comprising 11 taxa of grade Ⅴ, 15 taxa of grade Ⅳ, 33 taxa of grade Ⅲ, 15 taxa of grade Ⅱ, 56 taxa of gradeⅠ. The naturalized plants were identified as 67 taxa and the percent of naturalized index (NI) was 8.3% of total 804 taxa vascular plants.

Gonadotropin-inhibitory hormone (GnIH) has been found to inhibit the synthesis and release of gonadotropin (GTH) in avian and mammalian species. It was originally identified in the brain of a quail as a novel hypothalamic neuropeptide with a C-terminal Arg-Phe-NH2 motif (RFamide peptide). Homologs of this peptide have been identified in a couple of model fish species such as goldfish (Carassius auratus) and zebrafish (Danio rerio). Understanding GnIH system could be particularly useful in some aquaculture species with problems of frequent reproduction and/or precautious sexual maturation. However, GnIH system in such species has not been studied yet. In this study, we have identified a pupative GnIH gene in the Nile tilapia (Oreochromis niloticus). We also investigated the role of GnIH in the reproduction of this species. The full length sequence of putative tilapia GnIH gene coded for a protein (197 amino acids) containing two modified RFamides (MPLRF and LSQRF) and a LPQRF cDNA sequence of 594 bp. This putative GnIH gene showed high homology with the GnIH genes of Takifugu rubripes (72%) and Tetraodon nigroviridis (74%). PCR analysis showed that expression of this gene was ubiquitously distributed in the whole brain, ovary and testis as well as in the peripheral tissues examined in this study (liver, kidney, intestine, spleen, muscle and gill) except heart and eye. Expression level of this gene in sexually inactive group was significantly higher than the expression level in first gonadal development and sexually active groups (P<0.05). On the contrary, the expression level of LH-β gene was low in sexually inactive group but significantly higher in first gonadal development and sexually active groups (P<0.05). However, no significant difference was observed in the level of FSH-β gene expression between different reproductive phases in this species. In vitro studies revealed an inhibitory effect of GnIH on LH-β mRNA and FSH-β mRNA levels. No significant difference between GnIH and GnIH with LHRH-a treatments on LH-β and FSH-β mRNA expression in female tilapia pituitary cells.

This study was carried out to investigate the flora of Mt. Suan (Gyeonggi-do). The vascular plant were collected 13 times (from March to October 2011), and 402 taxa in total were identified, including 102 families, 274 genera, 354 species, 6 subspecies, 40 varieties and 2 forms. Among them, 8 taxa of Korean endemic plants and the Korea Forest Service-designated rare plants were identified as 5 taxa. Based on the list of plants which have been approved for overseas delivery, 10 taxa were recorded in the investigated area. The Ministry of Environment-designated specially plants were identified as 17 taxa. The naturalized plants were identified as 41 taxa and the percent of naturalized index (NI) was 10.2% of total 402 taxa vascular plants.

This study was carried out to investigate the flora of Is. Gageo (Jeollanam-do). The vascular plants were collected 13 times (from June 2008 to September 2011), and 465 taxa in total were identified, including 112 families, 301 genera, 402 species, 3 subspecies, 49 varieties, 9 forms and 2 hybrids. 171 taxa were first records for the region. Among them were seven taxa of Korean endemic plants and the Ministry of Environment-designated plants, which should be protected by the wildlife protection law, were identified as three taxa. There were 54 taxa of the flora with the levels Ⅲ,Ⅳ,Ⅴ in the floristic indicator plants which was designated by Ministry of Environment. The naturalized plants were identified as 29 taxa, and their naturalization ratio and urban index were found to be 6.2% and 9.0% respectively. There existed many kinds of plants resources having conservational value like Loxogramme salicifolia, Sarcandra glabra, Osmanthus insularis, Saussurea polylepis, Carex ligulata var. austrokoreensis, Hosta jonesii, Cyrtosia septentrionalis, etc., in this area. As therefore clear that appropriate plans to conserve the natural habitat of Is. Gageo must be made immediately.

Botrytis cinerea infects stems and leaves of greenhouse tomatoes and can cause serious economic losses. This study was conducted to develop environment-friendly control method against tomato gray mold. Antagonistic microorganisms (bacteria) were screened for control activity against Botrytis cinerea, both in vitro and in vivo, using stem sections. One hundred bacterial strains were isolated from the rhizospheric soil of various plants including tomato. These strains were screened for growth inhibition of Botrytis cinerea on agar plate by the dual culture and thirty strains showing strongly inhibitory effect against the pathogen were selected first. Among thirty strains, JB 5-12, JB 22-2, JB 22-3, U 4-8 and U46-6 reduced significantly disease incidence, when applied simultaneously with the pathogen. These results suggested that five antagonistic bacteria strains selected have the potential to control tomato gray mold in organic farming.

Fish reproduction is influenced by various external environmental factors. Among these factors, changes of photic conditions are thought be most closely related to the reproduction of many fish species. In recent studies, melatonin that mediates the changes of photic condition outside has been used in an attempt to get a similar effect to photoperiod manipulation without changing photoperiod. However, the effects of exogenous melatonin vary depending on life stages. We have previously investigated the effect of melatonin on reproductive activity in mature Nile tilapia (Oreochromis niloticus). In this study, effects of exogenous melatonin on the spawning activity, the rate of mouth brooding success rate and early survival rate of lavae produced from melatonin treated Nile tilapia were investigated. Nile tilapia at the time of puberty were randomly divided into three groups and fed on control (0 ㎍/g), low-dose melatonin (2.5 ㎍/g BW) or high-dose melatonin (25 ㎍/g BW) diet. Fish were reared indoor tanks at 27～28℃ under natural-photoperiod and fed twice a day at 10:00 and16:00 during the experiment (120 days). Fish were sampled to examine growth and gonadal development on Day 30, 60, 90 and 120. There were no significant differences of somatic growth between control (no melatonin) and melatonin-treated groups, indicating that melatonin administration did not cause any negative effects on the growth of experimental fish. The patterns of gonadal development were almost the same between control and melatonin-treated groups. In juvenile tilapia, treatment with low-dose melatonin resulted in the increase of spawning rate, the rate of mouth brooding success and early survival rate of laval tilapia. However, high-dose melatonin resulted in the decrease of spawning rate, the rate of mouth brooding success and early survival rate of laval tilapia, although the earliest spawning occurred in one of the high-dose group fish. Fish in high-dose melatonin group failed to recover from reproductively suppressed state even after the cease of melatonin treatment, indicating that too much melatonin might act negatively on spawning activities and gonadal maturation in Nile tilapia. In conclusion, the results from this study suggest the possibility that a pertinent dose of melatonin treatment can effectively accelerate the spawning rate and the rate of mouth brooding success, and bring positive effects on early survival rate of tilapia lavae.

This study was carried out to investigate the flora of uninhabited Island in the Deokjeok Archipelago. The vascular plants which were collected in 5 times (from Jun. 2009 to Apr. 2010) were identified as 350 taxa in total, including 89 families, 231 genera, 309 species, 5 subspecies, 31 varieties, and 5 forms. There were many useful plants such as 2 taxa of Korean endemics and 2 taxa of rare plants which were proposed by the Korea Forest Service. The specially determined plants which were categorized as 5 degrees in all by the Ministry of Environment appeared as 49 taxa; Degree Ⅴ was one taxon; Senecio nemorensis and Ⅳ was one taxon; Apocynum lancifolium and Ⅲ was 2 taxa; Stauntonia hexaphylla, Hylotelephium spectabile and Ⅰ was 45 taxa; Machilus thunbergii, Neolitsea sericea, Hedera rhombea, etc. Based on the plants which were approval objects when transfer overseas were 5 taxa, and 21 taxa of evergreen plants were recorded in the investigated area. The naturalized plants were identified as 15 taxa, and their naturalization ratio were found to be 4.2% respectively.

Photoperiod is known to be the most potent environmental stimulus for reproduction in many lower vertebrates, and it exerts an endogenous effect by causing a rhythmic change in melatonin level, which increases during the dark phase and decreases during the light phase. In recent studies, melatonin administration was capable of changing seasonal reproductive activities in several fish species, and also resulted in modulating the timing of smoltification in a salmonid fish (Amano et al., 2004; Ligo et al., 2005). In this study, we have investigated the changes of spawning activities (number of eggs, frequency of spawning) by oral administration of melatonin in the Nile tilapia, Oreochromis niloticus. Fish were obtained from a local fish farm (Chungju, Chung Buk) and acclimatized in fish rearing facilities in Sunmoon University (Asan, Chung Nam). Randomly selected 24 fishes (12 males, 12 females; 200～400 g in body weight, BW) were divided into three groups and each fish was accommodated into glass aquarium individually. Fish were fed either with control diet (0 ㎎ melatonin) or low-dose melatonin diet (0.3 ㎎ melatonin/㎏, BW) or high-dose melatonin diet (3 ㎎/㎏, BW). Fish were individually checked everyday for the presence of eggs in their mouths, and the eggs were removed and counted when found. Fish were fed twice a day, but melatonin treated diet was given only once a day at 10:00a.m.. The daily feeding ration was set at 2% of the body weight so that the fish ate all the pellets provided. Fish were sampled for blood parameters (Hb, Glu, GOT, GPT) on March 2 (Day 30), April 2 (Day 60), May 3 (Day 90), June 3 (Day 120) and July 14 (Day 160). The sampling was done between 14:00 and 16:00 p.m.. For the sampling, fish were anesthetized in 50 ppm benzocaine, and body length (BL) and BW were measured. Blood sample was collected using a heparinized syringe from the caudal blood vessel. Melatonin affects several photoperiodic signals including reproductive activities in fish. Low-dose melatonin administration appeared to disturb spawning and sexual maturation in Nile tilapia in this study. Fish treated with low-dose melatonin spawned less numbers of egg than the fish treated with high-dose. In contrast, high-dose melatonin administration caused more frequent spawning than low-dose melatonin. On the other hand, somatic growth and blood parameter were not affected by melatonin treatments. These results suggest that pertinent melatonin could be involved in providing photoperiodic information as short day photoperiod. Fish treated with over dose melatonin seemed to have no melatonin-free interval. In that circumstance the melatonin message might have not been conveyed as a proper signal.

This study was carried out to investigate the vascular flora of Mt. Munsu. The vascular plants collected in 13 times(from Mar. to Oct. 2009) were identified as 511 taxa in total, including 113 families, 332 genera, 445 species, 5 subspecies, 46 varieties, 5 forms. Among them, 6 taxa of the Korea Forest Service-designated rare & endangered plants and the Korean endemic plants were identified as 2 taxa. Based on the list of approved for delivering overseas of plants, 6 taxa were recorded in the investigated area. The Ministry of Environment-designated plants, which should be protected by the wildlife protection law, were identified as 2 taxa and 39 taxa of specially designated plants by the Ministry of Environment. The naturalized plants were identified as 53 taxa, and their naturalization ratio and urban index were found to be 10.3%, and 18.5% respectively. There existed many kinds of plants resources having conservational value like Ranunculus trichophyllus var. kadzusensis, Jeffersonia dubia etc. in this area, but there remains a fear of nature destruction's acceleration due to indiscriminate human development and access of a lot of visitors, so it is judged that there should be a management plan, such as a limit on the number of visitors or rest-year-system for restoration of nature.

Randomly Amplified Polymorphic DNA (RAPD) was performed to define the genetic variation and relationships of Artemisia capillaris. Fifteen populations by the distributions and habitat were collected to conduct RAPD analysis. RAPD markers were observed mainly between 300bp and 1600bp. Total 72 scorable markers from 7 primers were applied to generate the genetic matrix, and 69 bands were polymorphic and only 3 bands were monomorphic. The genetic dissimilarity matrix by Nei's genetic distance (1972) and UPGMA phenogram were produced from the data matrix. Populations of Artemisia capillaris were clustered with high genetic affinities and cluster patterns were correlated with distributional patterns. Two big groups were clustered as southern area group and middle area group. The closest OTUs were GW2 and GG1 in middle area group, and GB1 from southern area group was clustered with OTUs in middle area group. RAPD data was useful to define the genetic variations and relationships of A. capillaris.