Origin of the red imported fire ant (RIFA, Solenopsis invicta) is South America, a tropical climate region. It has settled in the invasive area, causing various problems. In recent, colonies of Solenopsis invicta were discovered in Busan in 2017, and then in Busan, Pyongtaek, Incheon, Daegu and Ansan in 2018. This study aims to validate 31 microsatlite loci referred from previous study for tracing origin of Solenopsis invicta colonies. We tried to test previously developed microsatellite loci so that we establish the protocol for molecular epidemiology of RIFA. We applied 31 microsatellite loci to DNA samples from the RIFA colonies found in Texas and Florida, USA. We will present 31 markers were divided into three injections and the amplification rate for each marker was shown as follows.

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.

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).

The present study examined the histological characteristics of adult testis in the long-beaked common dolphin (Delphinus capensis) from Korean waters and the localization of DEAD-box polypeptide 4 (DDX4; a germ cell marker) and vimentin (a Sertoli cell marker) expression in the dolphin testis compared with that in terrestrial mammals, including dogs and rats. The seminiferous tubules of dolphin testis have very small or completely closed lumens, and spermatogenic cells and Sertoli cells within the tubules cannot be differentiated. Immunohistochemical analysis showed that, in the dolphin testis, DDX4- and vimentin-positive cells were scattered extensively within the tubule, whereas in the dog and rat testis, DDX4 immunoreactivity was localized in spermatogenic cells of the adluminal compartment, and vimentin immunoreactivity was localized in Sertoli cells of the basal compartment in the seminiferous epithelium. These results suggest that the histological characteristics of the seminiferous tubules in the dolphin testis differ from those of terrestrial species.

토마토 TYLCV는 병이 발생되면 약제나 다른 방법으로 방제가 어려우므로 내병성 품종의 개발이 반드시 필요하다. 특히, TYLCV 저항성 유전자 Ty-1,2,3(부분우성)을 한 개체 내로 집적을 시켜서 저항성이 증대된 품종의 개발이 필요하다. 토마토 TYLCV 저항성 11-TY1-AV 등 7계통을 대상으로 보독인 담배가루이를 이용하여 표현형을 조사하였다. 이병성 대비(11-TY5-AV; 슈퍼썬로드)와 F3 세대 3계통 및 F2 세대 4계통을 TYLCTHV 균주를 이용하여 접종하였다. 접종 13일 후에 이병성 대비가 100% 이병증상을 나타내었으며, 이때 11-TY4-AV는 48개체 중에서 23개체가 이병되었으며, 11-TY6-AV는 42개체 중에서 14개체, 11-TY7-AV는 48개체 중에서 14개체, 11-TY8-AV는 48개체 중에서 15개체가 이병 되었다. F2 세대 4 집단 모두 p>0.05 수준에서 TYLCV 접종 후 표현형이 정상적인 유전분리비(3:1)를 보이는 것을 확인 하였다. 또, TYLCV에 저항성인 동일한 자원을 부계로 사용하더라도 모계로 어떤 것을 사용 하느냐에 따라서 저항성 정도가 다르게 나타나는 것을 확인할 수 있었다.

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.

본 연구에서는 전단변형을 고려한 비대칭 박벽 곡선보의 자유진동해석을 수행할 수 있는 일반이론을 제시하기 위하여, 3차원 연속체에 대한 가상일의 원리로부터 전단변형 효과를 고려하고 비대칭 박벽단면과 ？(Warping)을 포함하는 변위장을 도심 축에 대해 정의한 후 곡선보의 변형도-변위관계로부터 공간 박벽 곡선보의 일반화된 탄성변형에너지와 운동에너지를 새롭게 유도한다. 또한, 전단변형이 고려된 곡선보의 총포텐셜에너지에 대해 변분을 취함으로써 평형방정식과 힘-변위관계를 제시한다. 한편, 제시된 이론에 대해 등매개 보요소를 도입하여 유한요소 정식화를 수행하였으며 곡선보의 동적 거동특성을 조사하기 위하여 전단변형, 곡률효과 그리고 진동모드에 대한 매개변수 연구를 수행한다. 마지막으로, 본 연구의 타당성을 입증하기 위하여, 다양한 해석예제에 대한 3차원 고유진동수를 산정하고 타 연구자들의 결과 및 ABAQUS의 쉘요소를 이용한 해석결과와 비교ㆍ검증한다.

In this study, we constructed viral vector for soybean by using Soybean yellow common mosaic virus (SYCMV) infecting both Glycine max and Glycine soja. SYCMV-derived viral vector was tested to use as Virus-induced gene silencing (VIGS) vector for functional analysis of soybean genes and as protein expression vector for foreign protein expression. In vitro transcript with 5’ cap analog m7GpppG from a full-length infectious vector of SYCMV driven by T7 promoter was inoculated to soybean to test infectivity of the clone (pSYCMVT7-full). 5’-capped transcript was able to infect soybean plants. The symptoms observed in soybean plants infected by either the vector or the sap from SYCMV-infected leaves were indistinguishable, suggesting that the vector had an equal biological activity shown by virus itself. To further utilize the vector, an additional DNA-based vector was constructed. The full-length cDNA was inserted into a binary vector flanked by CaMV 35S promoter and the nopaline synthase terminator (pSYCMV35S-full). To test if the vector infects soybean and subsequently induces gene silencing, we prepared two constructs containing fragments of Phytoene desaturase (PDS) gene (pSYCMV35S-PDS1) and small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcS) gene (pSYCMV35S-rbcS2) from soybean plant. Plants infiltrated with the constructs through Agrobacterium-mediated method showed distinct symptoms such as photobleaching in plants infiltrated with pSYCMV-PDS1 and pale green or yellowing in plants infiltrated with pSYCMV-rbcS2. In addition, down-regulations of mRNA levels of two genes were confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). To test if the vector can be used for foreign protein expression in soybean plants, we prepared a construct encoding amino acids 135-160 of VP1 FMDV serotype O1 Campos (O1C) (pSYCMV35S-FMDV). Plants infiltrated with the construct through Agrobacterium-mediated method showed that soybean plant infiltrated with pSYCMV35S-FMDV only was detected by Western blotting using O1C antibody. These results support that SYCMV-derived viral vector can be used as VIGS vector or protein expression vector in soybean plants.