• The Plant Pathology Journal
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• v.40 no.5
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• pp.425-437
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• 2024

A large number of species in the genus Colletotrichum have been reported as causal agents of anthracnose on crops and wild plants in Korea. Many Colletotrichum isolates from the country preserved in the Korean Agricultural Culture Collection (KACC) were previously identified based on host plants and morphological characteristics, and it may lead to species misidentification. Thus, accurate fungal species identification using multilocus sequence analyses is essential for understanding disease epidemiology and disease management strategies. In this study, combined DNA sequence analyses of internal transcribed spacer, gapdh, chs-1, his3, act, tub2, and gs were applied to re-identify 27 Colletotrichum isolates in KACC. The phylogenetic analyses showed that the isolates resulted in 11 known species, they belong to the C. dematium species complex (C. hemerocallidis, C. jinshuiense, and C. spinaciae), the C. magnum complex (C. kaifengense and C. cf. ovatense), the C. orchidearum complex (C. cattleyicola, C. plurivorum, C. reniforme, and C. sojae) and the C. orbiculare complex (C. malvarum and C. orbiculare). Of them, C. cattleyicola, C. hemerocallidis, C. kaifengense, and C. reniforme were unrecorded species in Korea. In the view of host-fungus combinations, 10 combinations are newly reported in the world and 12 are new reports in Korea, although their pathogenicity on the host was not confirmed.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.04a
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• pp.49.2-50
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• 2005

• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.63-63
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• 2006

• Journal of Agricultural Extension & Community Development
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• v.6 no.2
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• pp.53-74
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• 1999

This study aimed at exploring new directions for revision of the Rural Development Law. Research and development for environmentally friendly agricultural technologies and localization of the extension offices and staffs were some of the important challenges to agricultural extension services in Korea. The study suggested new directions for revision of the Rural Development Law should consider new development and environmental concerns of agricultural sciences, and needs of farmers, local and central government. Some of major focus of the revised Rural Development Law should include the following; 1) Rural development programs should cover extended areas of newly developed concerns and target groups, 2) County and city administration should provide proper administrative and financial support for local agricultural extension center. 3) Areas for agricultural research and development should be extended to meet the needs of newly developed technologies and sustainable environment system at local level, 4) Monitoring and evaluation of extension efforts should be performed annually to support financially and to strengthen proper systematic linkage between national and local extension services.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.1
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• pp.14-19
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• 2015

In a previous report, we identified several candidate antimicrobial peptides through de novo RNA sequencing of the centipede Scolopendra subspinipes mutilans. Here, we identify and characterize one of these peptides, Scolopendrasin I. We identified the centipede antimicrobial peptide Cecropin from the centipede transcriptome using an SVM algorithm, and subsequently analyzed the amino acid sequence for predicted secondary structure using a GOR algorithm. We identified an alpha helical region of Cecropin and named it Scolopendrasin I. We then assessed antimicrobial and hemolytic activity of Scolopendrasin I. Scolopendrasin I showed antimicrobial activity against various microbes, including antibiotic-resistant Gram-negative bacteria, in a radial diffusion assay. Scolopendrasin I had potent antibacterial activity against acne-associated microbes in a colony count assay and showed no hemolytic activity in a hemolysis assay. In addition, we confirmed that Scolopendrasin I bound to the surface of bacteria via a specific interaction with lipoteichoic acid and lipopolysaccharide, two components of bacterial cell membranes. In conclusion, the results presented here provide evidence that this is an efficient strategy for antimicrobial peptide candidate identification and that Scolopendrasin I has potential for successful antibiotic development.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.511-520
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• 2022

Insect-resistant transgenic rice (Bt-T) expresses a toxic protein (mcry1Ac1) derived from the soil bacterium Bacillus thuringiensis found in the rice cultivar Dongjin with an insecticidal property against rice leaf roller (Cnaphalocrocis medinalis). In this study, to investigate the impact of Bt-T on non-target organisms, the feed and oviposition preferences and biological parameters of brown planthopper (Nilaparvata lugens Stål) were comparatively analyzed in four rice cultivars: Dongjin (parent variety), Ilmi (reference cultivar), Chinnong (brown planthopper resistant cultivar) and Bt-T. In the Bt-T and Dongjin cultivars, the feed preferences were 32.4 ± 8.3 and 34.1 ± 6.8%, and the oviposition preferences were 32.5 ± 5.1 and 30.0 ± 5.3% respectively, and there was no statistical significance between these rices. Additionally, in the Bt-T and Dongjin cultivars, the total lifespans from egg to adult were 39.5 ± 6.9 and 40.0 ± 5.8 days, and the weights of adult females were 1.78 ± 0.14 and 1.72 ± 0.16 mg, respectively. Therefore, there was no statistical difference in the biological parameters between these two varieties. Overall, the results indicate that the insect-resistant transgenic rice (Bt-T) did not negatively affect the reproduction and life cycle of brown planthopper, a non-target organism.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.12a
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• pp.395-400
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• 1998

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.2
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• pp.180-183
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• 2010

This study was performed to investigate the temperature-dependent development, longevity and oviposition of an indigenous larval parasitoid, Meteorus pulchricornis, on tobacco cutworm, Spodoptera litura. M. pulchricornis were reared at nine constant temperatures between 15 and $35^{\circ}C$. The developmental times of each three developmental stage decreased from 38.7 to 16.3 d between 15 and $30^{\circ}C$. However, M. pulchricornis showed longer developmental time at $32.5^{\circ}C$ (9.5, 7.7 and 17.2 days for each three developmental stage) than at $30^{\circ}C$ (8.9, 7.3 and 16.3 days for each three developmental stage). Immature M. pulchricornis could not develop any more at $35^{\circ}C$. The lower developmental threshold estimated by linear regression equation for the egg to cocoon, cocoon to adult emergence and egg to adult emergence were 5.1, 4.6 and $4.5^{\circ}C$. The thermal constant for each of the three stages were 217.2, 176.2 and 403.8 degree-days, respectively. When no food or 50% honey solution as a food source is provided for M. pulchricornis, the parasitoid survived for 8.3 and 55.9 days at $25^{\circ}C$, respectively. M. pulchricornis females laid 5.2 eggs daily and total of 131.6 eggs at $25^{\circ}C$ until it died. Peak age-specific fecundity was observed on $14^{th}$ day (9.6 cocoons) after parasitoid emergence and gradually decreased thereafter.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.1
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• pp.75-79
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• 2012

Low-melting-temperature agarose gel solution, as a novel porogen was combined with a silk fibroin solution to generate interconnected porous networks. The porosity of the resultant silk fibroin-agarose scaffolds was greater than that of the scaffolds generated with agarose and deionized water. The porosities of silk fibroin scaffolds containing agarose gel at 0.5%, 1.0%, 1.5%, 2.0% [w/v] were 110.9%, 111.7%, 120.9%, and 123.0%, respectively. Lastly, the internal space generated in scaffolds after dissolution of the agarose gel provides a good environment for cell growth and movement within the scaffold.

• Journal of Agricultural Extension & Community Development
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• v.7 no.2
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• pp.307-320
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• 2000

Agricultural extension services in Korea need to build new extension system to cope with the digital age and especially with shortage of extension educators which has been originated from the changing status from central to local government. The new trends including development of multi-media, wide-spreading of internet, and advent of internet broadcasting are offering the opportunities for new agricultural extension service. Utilization of agricultural internet broadcasting could be a new alternative for enhancing the efficiency of agricultural extension services. Agricultural internet broadcasting could support decision making of farmers by forwarding unique agricultural data which have been collected, compiled and processed by the Rural Development Administration. Farmers will be able to search useful agricultural data through agricultural internet broadcasting for more efficient farm management and marketing farm products. Agricultural internet broadcasting could utilize more prompt and abundant agricultural technology and management data compiled by the Rural Development Administration, and through this process, agricultural internet broadcasting could compensate the shortage of extension manpower. Through feedback process of agricultural internet broadcasting. farmers will be able to communicate more efficiently with extension educators to increase agricultural production and income. Agricultural Internet broadcasting could be an alternative to prevent farmers from being shunned in the information-based society.