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There has been a strong and urgent demand to diagnose community transmission-driven coronavirus disease 2019 (COVID-19) after it crossed borders. A large number of rapid and accurate tests and diagnoses are required at drive-through test stations, community clinics and hospitals. Isothermal amplification technology, such as loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA), provides excellent alternatives for resource limited test environments. LAMP has been shown to be comparable with polymerase chain reaction (PCR) and can be performed in less than 30 min by non-laboratory staff without ribonucleic acid (RNA) extractions commonly associated with PCR. LAMP tests on assays with SARS-CoV-2 and other pathogenic microorganisms, such as Dengue, Malaria, and Influenza viruses and Helicobacter pylori show color changes allowing test results to be interpreted by the color change of the assays. However, visual inspection of a large number of assays is prone to human error and manual record keeping makes test result tracking for an epidemiologic investigation very difficult and inefficient. The epidemiologic investigation is an essential part of the fight against community transmission-driven viruses. We have developed a very accurate and reliable, human error free, tablet PC-based portable device for colorimetric determination of assays including SARS-CoV-2 and other pathogenic microorganisms.

Wheat is a staple food in the Korean diet, which is increasingly becoming westernized. Because most domestic wheat consumption relies on imported wheat, we aimed to evaluate the allergy-inducible protein contents of commercial flours from imported and domestic wheat. Analysis of the protein contents by densitometry suggested that domestic wheat flours contain lower levels of high molecular weight glutenin and omega-gliadin (50 and 34% lower, respectively) than imported wheat flours. Therefore, domestic wheat flours are less likely to cause allergic reactions than imported wheat flours are. Based on the findings of our study, were commend increased consumption of domestic wheat flours to those who are sensitive to allergy.

Pseudomonas fluorescens , a widespread Gram-negative bacterium, is an ideal protein manufacturing factory (PMF) because of its safety, robust growth, and high protein production. P. fluorescens possesses a type I secretion system (T1SS), which mediates secretion of a thermostable lipase (TliA) and a protease (PrtA) through its ATP-binding cassette (ABC) transporter. Recombinant proteins in P. fluorescens are attached to the C-terminal signal region of TliA for transport as fusion proteins to the extracellular medium. However, intrinsic TliA from the P. fluorescens genome interferes with detection of the recombinant protein and the secreted recombinant protein is hydrolyzed, due to intrinsic PrtA, resulting in decreased efficiency of the PMF. In this research, the lipase and protease genes of P. fluorescens SIK W1 were deleted using the targeted gene knockout method. Deletion mutant P. fluorescens Δ tliA Δ prtA secreted fusion proteins without TliA or protein degradation. Using wild-type P. fluorescens as an expression host, degradation of the recombinant protein varied depending on the type of culture media and aeration; however, degradation did not occur with the P. fluorescens Δ tliA Δ prtA double mutant irrespective of growth conditions. By homologous expression of tliA and the ABC transporter in a plasmid, TliA secreted from P. fluorescens Δ prtA and P. fluorescens Δ tliA Δ prtA cells was found to be intact, whereas that secreted from the wild-type P. fluorescens and P. fluorescens Δ tliA cells was found to be hydrolyzed. Our results demonstrate that the P. fluorescens Δ tliA Δ prtA deletion mutant is a promising T1SS-mediated PMF that enhances production and detection of recombinant proteins in extracellular media.

β-glucan is the soluble dietary fiber component and occurs at its highest in barley. This study aims to evaluate the inheritance of β-glucan content in barley grains and to map quantitative trait loci (QTL) associated with this trait. F5-derived 107 lines from the cross of the six-rowed waxy hulless barley, ‘Yonezawa Mochi’ and the six rowed non-waxy hulless barley,’ Neulssalbori’ were measured for their agronomic traits and β-glucan level at four different environments. These recombinant lines showed significant genotypic variation (P < 0.01) and normal distribution for β-glucan content with a range of 43.6–62.1 g kg−1 across environments. A significant genotype-by-environment interaction was also found. The broad-sense heritability estimates for β-glucan content ranged from 0.42 to 0.82 across environments. Using one-factor analysis and composite interval mapping, a main effect of QTL associated with β-glucan content was identified in the genomic region near waxy gene (wx) and HVM4 on chromosome 7H. The major QTL at this region explained on average 44.4% of the variation for the mean of β-glucan content across environments with LOD values that ranged from 5.7 in Suwon in 2001 to 13.9 in Suwon in 2003. Two minor QTLs were identified but their significance of association with β-glucan content was inconsistent across environments.

Glucose and xylose are the most abundant materials in nature which can be used to produce ethanol by yeast fermentation. Three combinations of cultivation with glucose and xylose were carried out; separated, co-culture, and sequential fermentation with Saccharomyces cerevisiaeand Pichia stipitis. In the separated fermentation, S. cerevisiae fermented glucose to produce 14.5 g/l ethanol from 29.4 g/l glucose but hardly used xylose. However, P. stipitisutilized not only glucose but also xylose to produce ethanol 11.9 g/l and 11.6 g/l from 29.4 g/l glucose and 29.0 g/l xylose, respectively. In the mixture of glucose and xylose, P. stipitisfermented both sugars, producing 21.1 g/l ethanol while S. cerevisiaefermented only glucose, producing 13.4 g/l ethanol. In the co-culture and sequential fermentation, the co-culture showed more efficient ethanol productivity with 18.6 g/l ethanol than the sequential fermentation with 12.4 g/l ethanol. To investigate the effect of nutrients in the growth of microorganisms and ethanol production, yeast nitrogen base (YNB) was used in the sequential fermentation with S. cerevisiaeand P. stipitis. YNB supplemented some nutrients which S. cerevisiaeused up in the broth and the culture showed increased growth rate, increased consumption of xylose, and increased ethanol productivity producing 22.5 g/l ethanol from 54.6 g/l sugar with a yield of 0.41 g/g.

국내 보리 소비가 급격히 감소하면서 재배 면적도 줄어들어 겨울철 논을 이용한 보리 재배 농가의 대체 소득원이 보리를 활용한 조사료 생산이다. 경지이용률 제고와 양질의 조사료 공급은 국내 축산농가의 국제경쟁력을 올릴 수 있어 최근 청보리의 생산은 현저히 증가하고 있는 추세이다. 총체사료용 청보리는 식용보리에 비하여 전체적인 건물수량성이 높아야 하고 가축이 먹기에 좋도록 형태적으로도 개선되어야 한다. 그 동안 개발된 총체사료용 청보리는 벼와의 작부체계에 알맞도록 조숙이면서 건물수량이 ㏊당 10~12톤 (생체수량 평균 33톤/㏊)을 보이는 영양, 선우, 상원, 소만 등을 개발하였으며, 가축의 기호성이 좋도록 거친 까락을 매끈망으로 개선한 우호, 까락이 퇴화한 삼차망 보리 유연과 줄기에 잎귀를 없애서 부드럽게 만든 다미 등 초형을 개선하였다. 이러한 사료 전용 청보리 품종들은 사료가치도 우수한 것으로 평가되어 육종적으로 개선한 각 품종들의 고유 생육특성을 중심으로 보고하는 바이다.

Testing a large number of samples from field monitoring and routine indexing is cumbersome and the available virus detection tools were labor intensive and expensive. To circumvent these problems we established tissue blot immunoassay (TBIA) method an alternative detection tool to detect Barley mild mosaic virus (BaMMV) and Barley yellow mosaic virus (BaYMV) infection in the field and greenhouse inoculated plants for monitoring and routine indexing applications, respectively. Initially, leaf and stem were tested to determine suitable plant tissue for direct blotting on nitrocellulose membrane. The dilutions of antibodies were optimized for more efficient and economical purposes. Results showed that stem tissue was more suitable for direct blotting for it had no background that interferes in the reaction. Therefore, this technique was referred as direct stem blot immunoassay or DSBIA, in this study. Re-used diluted (1:1000) antiserum and conjugate up to 3 times with the addition of half strength amount of concentrated antibodies was more effective in detecting the virus. The virus blotted on the nitrocellulose membrane from stem tissues kept at room temperature for 3 days were still detectable. The efficiency of DSBIA and RT-PCR in detecting BaMMV and BaYMV were relatively comparable. Results further proved that DSBIA is a rapid, reliable and economical detection method suitable for monitoring BaMMV and BaYMV infection in the field and practical method in indexing large scale of barley materials for virus resistance screening.

Barley anther culture is hard working to plating picking out anther from the glume and demand long time comparing to be short available development stage for effective culture. Also, it has been treatment massive materials due to low plantlet comparing to get desirable plants intensively. Consequently, this experiment was carried out trying to be more high barley anther culture effectively in terms of save plating effort. Plating materials and culture temperature affected anther culture efficiency are among the inoculation tissues or organs such as anthers, spikelets and whole panicles, culture efficiency was higher with spikelets in two-rowed than six-rowed barley due primarily to a lower contamination, and calli were induced within 30 to 50 days. Callus induction and plant regeneration rates were higher in cultures at than at and . Days to callus induction were 25 to 50 days at and 50 to 60 days at .

As barley is recalcitrant to transformation with current methods, a new improved system is required to apply genetic transformation in breeding programs. In a previous study, we defined optimal conditions for plant regeneration (PR) using mature embryos. This study was conducted to establish an improved transformation system employing the previously adjusted regeneration conditions. Optimal DNA delivery condition for the embryogenic calli developed from mature embryos was bombardment pressure of 1,100 psi at the target distance of 6 cm. The feasibility of the regeneration and DNA delivery conditions was confirmed by developing transgenic barley plants transformed with the Arabidopsis nucleoside diphosphate kinase 2 (AtNDPK2) cDNA via particle bombardment of embryogenic calli from mature embryos. Stable integration of AtNDPK2 cDNA into barley genome was confirmed by PCR and Southern blot analysis of AtNDPK2 transgene. Transgenic plants showed about 10% reduction in membrane damage caused by methyl viologen, indicating the expression of AtNDPK2 transgene. The results demonstrated that the transformation system developed in this study employing the PR from mature embryo-derived embryonic callus is applicable in transgenic barley production.

The identification of molecular markers and marker-aided selection are essential to the efficient breeding of drought-tolerant plants. However, because that characteristic is controlled by many quantitative trait loci, such markers that can screen and trace desirable barley genotypes in a segregating population or germplasm have not yet been determined. Relative water content has been used to estimate drought tolerance in plants because it is highly correlated with the drought index of yield. To develop reliable gene-specific markers for identifying tolerant versus susceptible genotypes, we performed suppression subtractive hybridization to identify candidate genes. We used two domestic barley cultivars, one having the highest RWC (drought-tolerant ‘Chalbori’) and the other having the lowest (drought-susceptible ‘Daebaekbori’). In response to dehydration at the early seedling stage, rapid upregulation ofDehydrin3 (Dhn3) andDhn4 occurred in the drought-tolerant genotypes, but not in the susceptible ones. Similar results were obtained with mature plants growing under frequent drought stress in the greenhouse. In addition,Dhn3 andDhn4 conferred higher drought tolerance when they were over-expressed in transgenicArabidopsis. Thus, in addition to using assessments of RWC, we propose thatDhn3 andDhn4 expressions can serve as drought-induced gene-specific markers to determine drought-tolerant barley genotypes at the seedling stage.

Barley mild mosaic virus(BaMMV) is a soilborne Bymovirus vectored by root-infecting fungus, Polymyxa graminis. Mechanism of cultivar`s resistance to BaMMV in field tests are difficult to assess since resistance could be either due to the virus or to P. graminis, or both. Whereas, available mechanical inoculation methods for BaMMV and other related viruses are labor intensive, give inconsistent results and generally result in low infection rates. Inoculation method using stick with gauze(SWG) was developed for BaMMV. The improved method proved to be simple, efficient, and reliable. The infected leaf tissues were preserved by drying in a frozen state under high vaccum(freeze dried barley infected leaves) to circumvent reduction of virus infectivity during storage. Five Korean barley cultivars were mechanically inoculated with BaMMV-infected sap by the improved method. Infection rates obtained were compared with natural infection. Cultivar Naehanssalbori showed resistance to BaMMV in the field trials but was found highly susceptible in the greenhouse tests by mechanical inoculation, indicating that the field resistance may be possibly due to resistance to P. graminis.

Two distinct and stable isolates of Barley mild mosaic virus(BaMMV) designated as Naju82-S(severe) and Naju82-M(mild) were obtained. These two isolates differed in their symptomatology, virus transmission characteristics and cultivar specificity at various temperature. Thus, these isolates were referred to as strains in this study. BaMMV Naju-S strain showed severe mosaic symptoms accompanied by necrosis on the infected leaves. Naju82-S strain is more virulent demonstrated by shorter incubation period and relatively high virus concentration than Naju82-M strain. Five Korean cultivars were tested for their pathogenicity to different strains based on the rate of infection. Results showed that infection rate of cultivars to both strains did not significantly differed from each other. However, under different temperatures, the pathogenicity on the two cultivars such as cultivars Hopumbori and Sessalbori were significantly affected. Hopumbori was moderately resistant to both strains at and susceptible at . Similarly, Sessalbori was moderately resistant at to both strains but distinctly differentiated at wherein it was resistant to mild strain and highly susceptible to severe strain. Other cultivars including Baegdong, Jinyangbori and Neahanssalbori consistently showed susceptible reaction to both strains at varying temperatures tested in this study.

A nation-wide survey of introduced fish fauna in large river systems (>4th order streams, 28 sites, 9 river systems, total area 75,000 km 2 ) was conducted from July 1999 to January 2000 in South Korea. A total of 62 fish species (12,317 individuals, 16 families) were collected from two sampling programs. These included 32% of 194 known freshwater ichthyofauna of S. Korea. Dominant and subdominant species were Zacco platypus (16.2% relative abundance), Acheilognathus intermedia (10.6%), A. rhombea (7.2%), Opsariichthys bidens (7.1%), and Carassius auratus (6.9%). Fifteen exotic fish species have been introduced in S. Korea for food sources and about 120 species for aquarium use since the 1950s. In this study, five of the introduced food species were collected (Carassius cuvieri, 24 sites; Micropterus salmoides, 13 sites; Lepomis macrochirus, 7 sites; Oreochromis niloticus and Cyprinus carpio, 3 sites). C. cuvieri and M. salmoides were common (subdominant at 5 sites) and followed by L. macrochirus. These species were spread widely (93%; 26 sites) over all the study sites. Future research must consider the impacts of these exotic fish on natural ecosystem structure and function.

'Jeokwangtangkong' peanut (Arachis hypogaea L. subsp.fastigiata var. vulgaris) (Reg. no. CV-63, PI607913 is a spanish-type developed at the International Crops Research Insitute for the Semi-Arid Tropics (ICRISAT), Patancheru, Andhra Pradesh, India It was introduced into the Republic Of Korea in 1989 as ICGV 86326. After five years of evaluaton, it was released in 1996 as Jeokwangtangkong for cultivation in Korea.