국화에서 줄기괴저바이러스와 토마토반점위조바이러스를 매개하는 것으로 알려진 꽃노랑총채벌레 약충과 성충이 잎, 꽃, 과실의 흡즙을 통해 확산시킨다. 최근 무분별한 농약 사용으로 약제저항성 계통 출현이 지속적으로 보고되고 있다. 총채벌레류는 식물바이러스 매개하는 시간이 짧아 상대적으로 효과가 낮은 약제로는 총채벌레 방제효과를 기대하기가 어렵다. 시판되는 국화 총채벌레류 등록 살충제 10종을 꽃노랑총채벌레 발육단계별(약충, 번데기, 성충)로 살포한 결과, 유효성분 피롤계 클로르페나피르, 카바메이트계 벤퓨라카브와 스피노신계 스피네토람이 함유된 약제가 우수한 살충력을 보였다. 총채벌레류 화학적 방제를 위해서는 위 성분이 함유된 살충제를 교호로 사용하는 것이 효과적일 것으로 보여진다.

Many β-lactam antimicrobials, including cephalosporins, have been used in both veterinary and human medicine in the treatment of zoonotic and infectious diseases. Especially, third-generation cephalosporins such as ceftiofur have been approved for systemic use in food-producing animals, which has resulted in the emergence of β-lactamase genes. This study aimed to investigate the occurrence of β-lactamase-producing E. coli isolated from commercial layers and characterized their antimicrobial resistance and virulence genes. Among the 85 cefotaxime (CTX)-resistant E. coli, all isolates showed resistance to at least one antimicrobial, and the rates of resistance to nalidixic acid, cephalothin, ampicillin, and cefazolin were more than 50.0%. In particular, 28 isolates were identified as containing b-lactamase genes. The extended-spectrum β-lactamase (ESBL) and plasmid-mediated AmpC genes blaCTX-M-1, blaCTX-M-14, blaCTX-M-15, and blaCMY-2 were detected in 1, 6, 5, and 4 isolates, respectively. The non-ESBL/pAmpC gene blaTEM-1 was detected in 12 isolates. The distribution of antimicrobial resistance genes in 28 β-lactamase-producing E. coli was as follows: aac(3)-II (64.3%), sul2 (32.1%), tetA (28.6%), sul1 (25.0%), cmlA gene (25.0%), and tetB (14.3%). In total, 6 virulence genes (astA, eaeA, escV, fimH, iucC, and papC) were also identified and the rates in virulence gene were as below: fimH (92.9%), iucC (25.0%), astA (21.4%), papC (10.7%), eaeA (7.1%) and escV (7.1%). Our findings suggest that antimicrobials used in commercial layer must be regulated in Korea, and comprehensive surveillance is necessary to prevent the dissemination of resistant isolates.

프리지아 ‘Sweet Lemon’은 2007년 농촌진흥청 국립원예특작과학원에서 흰색 겹꽃 ‘Teresa’품종과 노랑색 반겹꽃 ‘Yvonne’ 품종을 교배하여 획득한 종자로부터 2007년 연노랑색 향기가 강한 겹꽃 프리지아 계통을 선발하여 품종으로 개발되었다. 2008년부터 2014년까지 개화 생육특성검정 및 육성계통평가회의 기호도 평가를 통해 선발되어 2015년 ‘Sweet Lemon’ 으로 명명되었다. ‘Sweet Lemon’은 연노랑색(RHS color chart Y2B) 겹꽃 프리지아 품종으로 화폭은 6.8cm이며 분지수는 6.7개로 다수확성 품종이다. 초장은 99cm로 초세가 강하며 대조품종 ‘Yvonne’ 91.7cm에 비해 34.7cm 더 크다. ‘Sweet Lemon’의 소화수 및 소화장은 각각 10.7개, 7.7cm로 ‘Yvonne’ 9.7개, 8.3이며 개화소요일수는 126일로 대비품종 보다 약 20일 정도 빠르다. 이 품종의 절화수명은 약 8.7일이며 자구번식력은 5.6배로 대조품종에 비해 우수하다. GC/MS를 이용한 향기분석 결과 총 58개의 방향성 화합물이 검출되었으며 주요성분은 linalool, alpha-Terpineol, alpha-Selinene, limonene이었다.

Poultry play an important role in meeting the protein demand through the supply of chicken meat and eggs, and antimicrobial-resistant bacteria can be transmitted from poultry to humans through the food chain. In this study, 716 E. coli isolates were collected from poultry industry in Korea during the period from 2016-2018. Among the cephalosporin antimicrobial, the rate of resistance to first-cephalosporins (cefazolin and cephalexin) was more than 18.0% but secondcephalosporins (cefoxitin and cefuroxime) and four-cephalosporins (cefepime) was less than 10.0%, without any differences based on the poultry. In quinolone antimicrobial, the rate of resistance to nalidixic acid was more than 46.0% in all poultry but ciprofloxacin was more than 44.0% in broiler farm and chicken meat and less than 18.0% in layer farm and egg. In addition, the rate of resistance to ampicillin and tetracycline was more than 30.0% without any differences in poultry, but the rate of resistance to amoxicillin - clavulanate, trimethoprim - sulfamethoxazole, imipenem and gentamicin was higher in broiler farm and chicken meat than in layer farm and egg. MDR was detected in 120 (60.6%), 113 (79.6%), 80 (37.0%), and 75 (46.9%) isolates from broiler farm, chicken meat, layer farm, and egg, respectively, with an overall prevalence of 54.2% (388/716).

후각 신경 시스템은 일반 생활 환경에서 많은 다양한 화학 물질을 인식하고 구별한다. 곤충에서는 다양한 화학 물질을 기호적 또는 회피적인 특이성을 부여하고 이를 구분해 낼 수 있는 고도로 발달된 후각신경 수용체들로 구성된 냄새 맡는 (odorant-gated) 이온 채널 군을 진화시켰다. 최근에 후각 수용체와 단백질을 포함한 olfaction 관련한 진딧물 게놈 밝혀졌고, 초파리에서 다양하게 분화되어 있는 후각 수용체들이 보고되고 있다. 후각 신경 수용체의 유전체는 매우 높은 보전적인 염기 서열을 가지고 있으며, 체계적인 신호 전달 시스템을 갖추고 있다. 대표적 수용체인 odorant-gated ion channels comprised of a highly conserved co-receptor (Orco)는 중심 구멍 주위에 대칭 적으로 배열된 4 개의 서브 유닛을 갖는 homotetramer 채널 구조를 가지고 있다. 이는 인체 내에 존재하는 7-transmembrane receptor와 매우 유사한 구조를 형성하고 있고, 신경전달물질의 수용체와 매우 유사한 구조적 형태 및 gating mechanism을 가지고 있다. 본 연구에서는 초파리에서 분리한 후각 신경 수용체 하위 유형인 OR65 유전자 분리하여 세포 발현 시켜 Xenopus oocyte를 이용하여 Whole cell voltage clamp recording을 실시하였다. 본 수용체의 성공적인 발현 이후 유해 해충 유인제 개발 회사인 마이크로자임의 미생물 배양 추출물을 이용해서 후각 신경 수용체 활성 조절 여부를 연구하였다. 미생물 배양 추출물을 10,000배 희석한 recording media에서 수용체의 활성을 확인하였고, 이를 농도 별로 처리하여 농도 의존성 수용체 활성 작용을 확인하였다. 따라서 곤충의 후각 신경 수용체 활성 조절 시스템을 이용하여 유인물질 또는 기피 물질을 발굴할 수 있으며, 본 연구를 통해서 MZ01은 곤충 수용체 OR65를 활성 시킴으로써 유인 현상을 나타내며, 본 연구를 통해서 현장에서 검증된 미생물 배양 추출물의 성능을 과학적 분석으로 결과를 제시하였다.

농업용 무인멀티콥터를 활용한 방제면적은 수도작은 물론 밭작물에서도 방제 범위가 확대되고 있다. 밭작물은 작물의 형태가 다양하여 비행속도, 살포높이 등을 최적화하는 연구가 필요하다. 본 연구에서는 배추, 대파, 고추에서 발생하는 나방류에 대하여 무인멀티콥터의 살포 높이에 따른 방제효과를 확인하였다. 살포된 약제가 작물에 부착되는 정도를 조사한 결과, 배추는 2m, 대파는 3~4m, 고추는 모든 높이에서 비슷한 부착정도를 보였지만, 전체적으로 부착량이 적고 불균일 하였다. 살포 높이별 방제효과는 작물별로 각각 배추(9~10엽기)는 2m높이, 고추(약 1.2m)는 2~3m, 대파(약 60cm)는 2, 3, 4m 각각 비등한 방제효과를 보였다. 각각의 작물모두 경엽처리 대비 약효가 미흡하였으며, 고추는 4m높이 살포시 방제효과가 현저히 낮았다.

Glutathione S-transferase (GST) is a key gene involved in multiple stress tolerance in all living organisms, though it is still to be disclosed the gene function in teff grass [Eragrostis tef (Zucc.)Trotter].The objectives of this study were to clone and molecular characterization of GST gene in teff grass. We characterized GST1 from teff grass (EtGST1), it composed of a 645-bp open reading frame (ORF) that encoded 195 amino acid residue. Further, we transformed EtGST1 in E.coli BL21 (DE3) cells. This recombinant EtGST1 in E.coli BL21(DE3) induced at 37°C temperature. In addition, Growth of cells overexpressing EtGST1 rapidly increased in the presence of polyethylene glycol (5%), heat (46°C), NaCl (0.6%), and arsenic (1 mM) than that of cells harboring an empty vector. These results suggest that EtGST1 would be suitable candidate for improving tolerance in forages and/or grasses species against multiple abiotic stresses.

Cold, salt and heat are most critical factors that restrict full genetic potential, growth and development of crops worldwide.. In this study, we applied an annealing control primer (ACP) based GeneFishing approach to identify differentially expressed genes (DEGs) in annual ryegrass (cv. Kowinearly) leaves under cold, salt and heat stresses. Two-week-old seedlings were exposed to cold (4°C), salt (NaCl 200 mM) and heat (42 °C) treatments for 6 h. A total 8 differentially expressed genes were isolated form ryegrass leaves. These genes were sequenced then identified and validated form National Center for Biotechnology Information (NCBI) database. We identified several promising genes encoding light harvesting chlorophyll a/b binding protein, alpha-glactosidase b, chromosome 3B, elongation factor 1-alpha, FLbaf106f03, complete genome, translation initiation factor SUI1, and glyceraldehyde-3-phosphate dehydrogenase. These genes were potentially involved in photosynthesis, plant development, protein synthesis and abiotic stress tolerance in plants. These genes might be useful for the enhancement of abiotic stress tolerance in fodder crops along with crop improvement under unfavorable environmental conditions.

To be better fit for highways, pavement systems are required to provide comfortable and safe driving and be structurally durable. Composite pavements can be an effective option as they are more durable by placing a high functional asphalt overlay on a rigid concrete base layer. In order to apply a composite pavement system to the field, it is necessary not only to develop technologies that prevent reflecting crack and deterioration of the base layer, but also to improve bonding performance of materials and ensure structural performance as a pavement system against traffic loading. In advanced countries like Japan, USA and Europe, high-functional composite pavement systems are being put into practice across new highway networks. In this study, we evaluated structural performance (rutting, reflecting crack, and deflection) by applying traffic loads of actual highways through an accelerated pavement tester (APT) of a composite pavement section made up of a quiet porous surface laid over a water-proofing layer, a continuously reinforced concrete base, and a lean concrete sub-base layer, which was developed with new pavement methods used for each layer prior to field application. The APT specimen was constructed with paving materials and equipment actually used on site in the same dimensions (W3.5m*L14m*H2m) as actual highway sections in Korea, and 3-axle double-wheel heavy load (45ton) cart type KALES(Korean Accelerated Loading and Environmental Simulator) traveling on the specimen in both directions was used to simulate traffic loading. After applying around 8,574,000 ESALs of traffic loads, no reflecting crack occurred on the asphalt surface of the composite pavement, without surface distress except for rutting. In order to examine what causes rutting of pavements, we surveyed thickness of pavements by layer and measured asphalt density.

The objective of this study was to evaluate the effectiveness of various crack inducers to be used in the advanced reinforced concrete pavement (ARCP) by conducting yard tests. Some of cracks are induced in ARCP to reduce the stresses in steel bars and to form more uniformly spaced cracks so that the required steel bar amount can be decreased and at the same time the pavement performance can be improved. In this study, an experimental ARCP was constructed for the length of 22.4 m, width of 1.12 m, and thickness of 0.26 m. The anchor lugs were placed at both ends of ARCP to pretend continuities of the system. 8 crack inducers with a uniform spacing of 2.8 m were installed in different manners when placing concrete, so the test length of the experimental ARCP was 19.6 m. The variables of crack inducers included the shape, material, installed depth, and installing method. The basic shape of the crack inducer represented a round face and a flat opposite face with a height of 50 mm and a width of 10 mm. The slightly different shaped crack inducers were installed for inducing cracks at both ends of ARCP. The crack inducers were primarily made of glass fiber reinforced plastic (GFRP) but a crack was induced using a polyethylene sheet inducer. The installed depths of the crack inducers were 30, 40 and 70 mm to the top of the crack inducer from the pavement surface. Most crack inducers were preinstalled on the transverse steel bar locations before concrete pouring, but 2 crack inducers were installed just after concrete placement when concrete was still fresh. The temperature measurement sensors of i-Buttons and thermocouples were installed at the top, middle and bottom of slab to measure the temperature variations of slab. The displacement transducers were also installed at the crack locations to measure the crack width movements. The experimental results showed that the cracks were induced at all the locations where the crack inducers were placed. In addition to the induced cracks, just one crack was formed naturally. The crack patterns on the surface of pavement were all comparable. The crack width measurement data showed that there were slight differences in the crack width movements among the cracks but all the cracks including both the induced and naturally formed cracks moved little within a 0.1 mm range. Therefore, any type of the crack inducers employed in this study can be used to initiate cracks in ARCP.

Roller-compacted concrete (RCC) has been widely used for construction of pavements [1]. The strength of RCCP can be obtained from not only hydration of binder but also the aggregate interlock resulted from roller-compaction [2]. For this reason, RCCP normally achieves higher strength compared to conventional concrete pavement with similar cement content. Even though RCCP can be provided a good structural performance, it has been difficult to verify the long-term performance though actual field construction. Therefore, this study aimed to investigate the fatigue characteristics and crack development in RCCP based on full-scale fatigue test and accelerated pavement test. In case of full-scale fatigue tests, fatigue behavior was evaluated by using 1 m × 1 m dimensional RCC slab specimens obtained from the field in order to consider the field variability. Fatigue equation derived from this study shows that the number of load repetitions which causes fatigue failure at the same stress level is slightly larger than that of PCA fatigue equation. In order to evaluate the performance of RCCP, two phases of accelerated pavement test (APT) were conducted. In phase one, the performance of RCCP at two different strengths (35.6 and 30.4 MPa) was evaluated. In phase two, the performance of RCCP with different thickness (5, 7.5 and 10 cm) was investigated. The number of load repetition of fatigue crack occurrence in each section was compared to the estimated fatigue failure determined from fatigue equation of RCCP. The crack development in each section was compared to the AASHTO crack model for JPCP. Overall, it was confirmed that RCCP has equal or better performance compared to JPCP the estimation in term of fatigue cracking. The fatigue equation from PCA and cracking model from AAHTO can be used on RCCP at certain design thickness range.

G protein-coupled receptors (GPCRs) belong to cell membrane protein family, which regulate various physiological process such as reproduction, behavior and immune etc. In other to identify the GPCRs in pheromone gland of Maruca vitrata, we carried out transcriptome analysis from both females. Transcriptome analysis in the pheromone gland yielded approximately 22Gb and 47,528 transcripts showed positive FPKM value. 48 Genes involved in GPCRs were identified such as pheromone biosynthesis activating neuropeptide receptor (PBANr), prostaglandin receptors, neuropeptide receptor, 5-hydroxytryptamine receptor, galanin receptor, calcitonin gene-related peptide receptor, diuretic hormone receptor, gonadotropin-releasing hormone receptor, frizzled and orphan receptors, etc. Various expression of GPCRs in the pheromone gland indicates the role of pheromone gland may not be limited to the production of pheromone.

Haemaphysalis longicornis (Acari: Ixodidae) is a medically important arthropod vector of tick-borne diseases, especially the severe fever with thrombocytopenia syndrome (SFTS). To establish a management strategy against tick-borne diseases, it is fundamental to understand the basic biology of vector species. Therefore under laboratory conditions, we evaluated the horizontal movement of adult and nymph stages of H. longicornis to better understand their dispersal behaviors. In the experiments, field populations were subjected to video recording of the horizontal movement of the ticks in a petri-dish arena for 3 hours. Our results indicate that nymphs showed a significantly higher mobility than adults, whereas there was no significant difference in angular velocity. Nymphs moved 3.74 ± 0.26 m at an angular velocity (AV) of 1.60 ± 0.07 deg/s. and adults moved 2.91 ± 0.26 m at an AV of 1.61 ± 0.14 deg/s.

세계적으로 관상작물의 중요한 나방류 해충의 하나인 Duponchelia fovealis Zeller가 2015년과 2016년에 경기도에서 처음으로 발견되었다. 유충이 꽃기린(Euphorbia milii)의 줄기 속을 파고 들어가거나 게발선인장(Schlumbergera truncata)의 잎을 가해하는 피해가 확인되었다. 유충과 피 해 확인 직후 합성농약을 살포하였고, 현재까지 추가적인 발견은 없었다.

The objective of this study was to investigate the effects of freeze dried placenta supplementation on reproductive performance, colostrum and plasma biochemical composition in pregnant sows. Eleven Landrace × Large white sows were fed with corn-soybean meal diets supplemented with or without 1% freeze dried placenta powder from 10 days before their expected farrowing dates until 10 days postpartum. The colostrum protein content was significantly higher(P=0.043) in the treatment group than in the control group. Compared to the control group, the immunoglobulin G(IgG) concentration in the colostrum was significantly higher(P=0.004) in the treatment. In day 25 piglets plasma, the IgG concentration was higher(P=0.184) in the treatment than the control. The mortality rate was lower(P=0.102), and the piglet weight gain was higher(P=0.35) in the treated group. Overall, the treatment group showed greater levels of protein and IgG concentration in the colostrum, when compared to control group. Therefore, the freeze dried placenta supplementation on pregnant sows can enhance its colostrum composition, hence decrease the mortality and increase the growth rate of piglets.

The ability of antimicrobial resistant Salmonella strains to cause invasive disease can be attributed to various virulence genes. In this study, the virulence genes located in SPI-1, SPI-2, SPI-5, SPI-11 were found in all antimicrobial-resistant Salmonella isolates. This suggests that these genes play important roles in Salmonella invasion, growth, or survival in the host. The association between the presence of virulence genes and antimicrobial resistance was assessed using the Spearman’s correlation coefficient, and there is a positive association between the gatC, tcfA, hylE, spiA, pagC, msgA, invA, sipB, prgH, spaN, orgA, tolC, iroN, sitC, lpfC, and sopB genes, and resistance to CF, NA and S. This suggests that the association between antimicrobial agents and virulence genes has been shown to vary with the types of antibiotics that are commonly used in different countries. These different associations can be explained by the mechanisms underlying pathogenicity and the acquisition of resistance genes by Salmonella.