The biological efficiencies of promising Pleurotus spp. were evaluated. Pleurotus ostreatus, Pleurotus tuberregium,and Pleurotus sajor-cajuwere investigated at temperatures of 22oC, 20oC, and 18oC to determine their ability to adapt to temperatures that are likely to be found in subtropical regions. The experiment was conducted using a substrate comprising Popular sawdust 60% + cotton seed 20% + beet pulp 20% under a relative humidity of 65%. The results indicated that there were significant differences in terms of biological efficiency between the species: P. tuber regium 128.84% at 22oC, P. ostreatus 108.41% at 22oC, and P. sajor-caju is 80% at 20oC. The common temperatures at which all species showed the highest biological efficiencies were 22oC and 20oC. Therefore, the production of the evaluated species was equal to or surpassed biological efficiencies reported in tropical environments, thereby demonstrating a potential opportunity to adapt to tropical environments without compromising quality standards.

Ocean biogeochemistry plays a crucial role in sustaining the marine ecosystem and global carbon cycle. To investigate the oceanic biogeochemical responses to iron parameters in the tropical Pacific, we conducted sensitivity experiments using the Nucleus for European Modelling of the Ocean–Tracers of Ocean Phytoplankton with Allometric Zooplankton (NEMO-TOPAZ) model. Compared to observations, the NEMO-TOPAZ model overestimated the concentrations of chlorophyll and dissolved iron (DFe). The sensitivity tests showed that with increasing (+50%) iron scavenging rates, chlorophyll concentrations in the tropical Pacific were reduced by approximately 16%. The bias in DFe also decreased by approximately 7%; however, the sea surface temperature was not affected. As such, these results can facilitate the development of the model tuning strategy to improve ocean biogeochemical performance using the NEMOTOPAZ model.

The Gwangneung arboretum, affiliated to the Korea Forest Research Institute, was established in 1987 and it became the Korea National Arboretum (KNA) in May 24, 1999. The entomological collection of KNA currently holds a total of 510,365 specimens of 6,849 species including more than 330 type specimens of Lepidoptera, Hemiptera, Hymenoptera, and Coleoptera are deposited. As the results of recent systematic studies by KNA entomologists, 67 new species were described, and 108 species were newly recorded from Korea and other countries. Not only we have conducted taxonomic studies but also have broaden our research boundary to natural enemy surveys for pine wilt disease vectors, plant and insect interaction, and exotic insect species monitoring. In this presentation, we would like to briefly introduce current entomological researches of KNA in the hope of future collaborations with other entomologists.

Two infamous ant species, red imported fire ant (RIFA, Solenopsis invicta) and tropical fire ant (TFA, S. geminata), originated from South America are invading and harming many countries around the world. Among them, RIFA, known as one of the 100 world’s worst invasive alien species, has been discovered in South Korea; in Busan (Gamman CT) in 2017, and subsequently in Busan (Hutchison CT), Pyongtaek, Incheon and Daegu in 2018. With these relentless introduction of RIFA, South Korea is not safe no more from these ants and faces a risk of settlement. Our research goal is tracing the country origin of invasive populations of RIFA and TFA based on molecular epidemiological approach. We are conducting both microsatellite and genome-wide SNP analyses in order to derive a complementary interpretation. These two methodologies are expected to result in improved resolution in population genetics analysis. Nevertheless, this work needs collaboration of many countries belonging to the range of origin and invasion of RIFA and TFA. We will briefly introduce our research project and progress of collaboration research.

PURPOSES : Thermal cracking (also called low-temperature cracking) is a serious stress for asphalt pavement, especially in eastern South Korea, the northern USA, and Canada. Thermal cracking occurs when the level of thermal stress exceeds the corresponding level of low temperature strength of the given asphalt materials. Therefore, computation of thermal stress is a key factor for understanding, quantifying, and evaluating the level of low-temperature cracking resistance of asphalt pavement. In this paper, two different approaches for computing thermal stress on asphalt binder were introduced: Hopkins and Hamming’s algorithm (1967) and the application of a simple power-law function. All the computed results were compared visually; then the findings and recommendations were discussed. METHODS: Thermal stress of the tested asphalt binder was computed based on the methodology introduced in previous literatures related to viscoelastic theory. To perform the numerical analysis, MATLABTM 2D matrix-correlation and Microsoft Excel visual basic code were developed and used for the function fitting and value-minimization processes, respectively. RESULTS : Different results from thermal stress were observed with application of different computation approaches. This variation of the data trends could be recognized not only visually but also statistically. CONCLUSIONS: It can be concluded that these two different computation approaches can successfully provide upper and lower limits (i.e. boundaries) for thermal stress prediction of a given asphalt binder. Based on these findings, more reliable and reasonable thermal stress results could be provided and finally, better pavement performance predictions could also be expected.

Incursions of red imported fire ant (RIFA), Solenopsis invicta into Korea have been increasing. After a first interception of a colony of S. invicta on Gamman pier, Pusan port while intensive surveillance by Animal & Plant Quarantine Agency (APQA) in September 2017, three more RIFA colonies have been found in sea port piers of Pyeongtek, Incheon and Pusan cities. The social forms and mitochondrial DNA haplotypes of the intercepted RIFA colonies were analysed by allelic discrimination assay (peptide nucleic acid probe based RT-PCR) of Gp-9 gene and mt-DNA fragment of 768 bp, which is part of the Cytochrome oxidaseⅠ gene. The colony on Gamman pier, intercepted in Sep. 2017 was previously reported as a haplotype 5 (H5) of mitochondrial DNA and a social form of polygyne. The colony on Hutchison pier of Pusan port, intercepted in June 2018 were confirmed as a H22 haplotype and a monogyne. Those different social forms show different origins of each colonies. Those on piers of Pyeongtek and Incheon ports, also found in 2018 were confirmed samely as H22 and monogyne. However, it could be putatively assumed that those two colonies were differently introduced via different container cargoes, considering those colonies were found in container yards of distantly located different sea ports. More genetic variation analyses using diverse sets of molecular markers such as microsatellites, genome-wide single nucleotide polymorphisms, etc. in nuclear gens are being proceeded for more exact introduction routes (origins).

Healing for the Jeju 4.3 survivors and families progressed significantly after the work of the 2000 National 4.3 Committee and the 2005 Truth and Reconciliation Commission. Acting on these investigatory organizations’ recommendations and the expressed desires of the Jeju people, the Korean government began a healing process that included a presidential apology, a government-sponsored museum and an extensive public memorial and gravesite for known victims—albeit without individual reparations. American and Korean scholars also point to the United States’ partial responsibility for Jeju 4.3 and its lack of participation in redress efforts. Acknowledgment of the United States’ historical role in Jeju 4.3 by the Korean and U.S. governments today may be one of the crucial next steps toward genuine reparatory justice for the Jeju people and for Korean society. It may also bolster U.S. legitimacy globally as a democracy actually (and not just professedly) committed to humanrights.The United States grounds its global moral authority as a democracy in its stated commitment to human rights. But a genuine commitment entails acknowledging and actively repairing the damage caused by its participation in human rights atrocities—even decades ago. Its legitimacy as a democracy depends upon doing so—and after two damaging wars the United States needs to bolster its moral authority internationally. If America under President Obama, with its security pivot toward Asia, is to reclaim full legitimacy as a democracy committed to human rights, if there is to be complete social healing for the Jeju 4.3 survivors and families and for the Korean government and people—if the “han,” the deep sense of suffering from injustice, is to be lightened—then the United States needs to mutually and actively engage in the reconciliation process. The time is now.

Lentinus lepideus is an edible mushroom, belongs to the family Tricholomaceteae and order Agaricales. The purpose of this study was to evaluate the antioxidant activities, tyrosinase inhibitory effects on the fruiting bodies of L. lepideus extracted with acetone, methanol and hot water. The antioxidant activities were performed on β-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging, and ferrous chelating abilities. In addition to this, phenolic acid and flavonoids contents were also analyzed. Hot water extract of L. lepideus showed the strongest β-carotene-linoleic acid inhibition as compare to others extracts. At 8 mg/ml, methanolic extract showed a high reducing power of 1.21. The scavenging effects on 1,1-diphenyl-2-picrylhydrazyl radicals, acetonic and methanolic extracts were effective than hot water extract. The strongest chelating effect (87.50%) was obtained from the methanolic extract at 1.0 mg/ml concentration. Antioxidant activities of the extracts from the fruiting bodies of L. lepideus were increased with the increasing concentration. After application of reverse phase high performance liquid chromatography, coupled to a diode array detector and electrospray ionisation mass spectra, six phenolic compounds namely, chlorogenic acid, vanillin, naringin, naringenin, formononetin and biochanin were identified from acetonic extract. Tyrosinase inhibition of acetonic, methanolic, and hot water extracts of L. lepideus were increased with the increasing of concentration. Results revealed that acetonic and methanolic extract showed good, while hot water showed moderate activities of the tyrosinase inhibition at the concentration tested. This study suggests that fruiting bodies of L. lepideus can potentially be used as a readily accessible source of natural antioxidants.

장 건강에 유익한 프리바이오틱스 소재를 개발하기 위하여 배변을 촉진하는 효능을 지닌 붉은팥을 식품 발효에 이용되는 Bacillus subtilis KCCM 11965P로 발효하여 다음과 같은 결과를 얻었다. 붉은팥의 일반성분은 회분 3.35±0.04%, 조단백질 21.1±0.19%, 조지방 0.35±0.02% 함 유되었다. 붉은팥 원물 1%, 3%, 5%와 Bacillus subtilis KCCM 11965P 3% (v/v)를 접종하여 0, 24, 48, 72시간 배양 하였다. 배양액의 총균수를 측정한 결과 붉은팥 원물을 3% 첨가한 후 72시간 배양군에서 Bacillus subtilis KCCM 11965P 발효가 가장 적합하였다. 발효 시간에 증가함에 따라 총 폴리페놀 함량과 DPPH 라디칼 소거활성이 증가하였다. Protease 활성은 붉은팥 원물 5% 첨가한 후 72시간 배양한 군(2.69±0.003 unit/mL)에서 활성이 가장 높았다. 발효시간과 붉은팥 원물 첨가 농도가 증가함에 따라 α -amylase 활성도 증가하였으며, 붉은팥 원물 5% 첨가한 후 72시간 배양한 군에서 0시간 배양군(1.0±0.1 unit/mL) 보다 26.0±0.2 unit/mL로 증가하였다. Bacillus subtilis KCCM 11965P로 72시간 배양한 후 유리아미노산을 측정한 결과 leucine은 붉은팥 원물 5% 첨가한 0시간 배양군 5.22 mg/L 에서 67.59 mg/L로 증가하였으며, 비필수아미노산인 tyrosine은 5% 첨가 0시간 배양군 10.08 mg/L에서 259.35 mg/L로 증가하였다. 이와 같이 Bacillus subtilis KCCM 11965P로 붉은팥을 발효하면 항산화 활성, protease 효소활성, 및 α-amylase 효소 활성이 증가하였으며, 유리아미노 산과 유기산이 증가하였다. 붉은팥을 발효하는데 Bacillus subtilis KCCM 11965P가 적합할 것으로 판단되며, 붉은팥은 프로바이오틱스를 활성화시켜 장 건강을 증진시킬 수 있는 프리바이오틱스 소재로 개발할 수 있는 가능성을 시사 하였다.

Background : The organic matter content of land clearing or soil brought from an other place is very low, less than 0.5%. However, the organic matter content of natural habitat soil and leader farmhouse soil was two to three times higher than that of general farmhouse soil. As a result, the yield of Gastrodia elata was higher than that of general farmhouse. Therefore, this experiment was carried out to investigate the yield of G. elata according to the application of green manure crops (GMCs). Methods and Results : This experiment was carried out in a soil with organic matter content of 0.5% in rain shelter greenhouse. The kind of GMCs are corn, Sudan grass, sorghum and oats, and the throughputs per 10 a were 2,000 ㎏, 2,200 ㎏, 1,500 ㎏ and 700 ㎏ of each. The soil preparation was carried out after treated of GMCs at least one month before G. elata was formally planted. As the results of these experiment, organic matter content in soils increased 4 - 5 times compared with before treatment. As a result, the yield of G. elata increased by 21 - 41% in all treatments of GMCs. In addition, there was 2 - 5% more G. elata of good merchantable quality. However, the soil temperature in the summer season period of 2016 (7.1 - 8.31) was 1.2 - 1.6℃ higher than the previous year. The day when the outside temperature was above 30℃ was 41 days. It doubled from the previous year. Soil moisture content showed similar tendency according to treatments. As a result, 20 - 30% of high temperature damage and 20 - 50% of putrefaction occurred, and the total yield also decreased by 20 - 30% compared to normal year. Conclusion : In conclusion, some organic matter is needed for cultivation of G. elata. Therefore, it is considered that it would be better to keep the organic matter content at 2 - 3% when the destination are managed, and to use corn or Sudan grass as the GMCs.

Watermelon (Citrullus lanatus) is one of the most economically important cucurbitaceous crop over the world. Anthracnose disease caused by Colletotrichum orbiculare, result to severe damage to cucurbits worldwide. Anthracnose is a typical plant disease which significantly affecting the yield of cucurbit crop. Pathogeneis-related (PR) proteins are well-known plant defense proteins against pathogens. Therefore, we observed PR genes expression patterns when watermelon got anthracnose disease. We did RT-PCR experiment to evaluate differences of PR genes expression pattern among Au-Producer(R), one of the representative of resistance watermelon varieties against anthracnose, and 920533(S), one of the representative of susceptible watermelon varieties against anthracnose. As a result, there were differences of the expression of several PR genes between the R and S watermelon. Analysis of the function of these genes is expected to perform in the future.