• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.33-36
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• 2007

To improve insecticidal activity of B. thuringiensis 2385-1 (Bt 2385-1), a recombinant plasmid, pHT1K-1Ac, was introduced into lepidopteran toxic Bt 2385-1 by electroporation. The presence of the recombinant plasmid in Bt 2385-1 after electroporation was confirmed by PCR. Bt 2385-1 transformant was named as Bt pHT1K-1Ac/2385-1 (1K-1Ac/2385-1). The 1K-1Ac/2385-1 transformant produced bipyramidal-shaped parasporal inclusion as like the wild-type strain, Bt 2385-1, and showed an 130 kDa band of Cry1Ac protein. The insecticidal activity of 1K-lAc/2385-1 against S. exigua was similar to that of Bt 2385-1 but the $LC_{50}$ value of transformant against P. xylostella was 1.8 times lower. Through these bioassay results, it was confirmed that toxicity of Bt 2385-1 transformant showed synergistic effect by introducing Cry1Ac. These results suggested that the multiple expressions of Cry proteins in a promising Bt strain may interact synergistically in insect midgut, resulting in increase of toxicity and expansion of host spectrum.

• Journal of Korean Society of Forest Science
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• v.97 no.5
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• pp.555-558
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• 2008

Trapping efficiency of various sex pheromone blends of the peach pyralid moth, Dichocrocis punctiferalis was compared by field study to develop monitoring system with its sex pheromone at chestnut orchards in Korea. Five candidates of the sex pheromone blends used for the field trapping of D. punctiferalis males were 70:30, 75:25, 80:20, 85:15 and 90:10 mixture of (E)-10-hexadecenyl aldehyde (E10-16:Al) and (Z)-10-hexadecenyl aldehyde (Z10-16:Al). All lures were treated with 1 or 2 mg of each blends. During 2 years of field survey, the 75:25 blend was usually the most effective in attracting males among 5 blends tested. For the 2nd generation, the best capturing activity for D. punctiferalis male was observed by lure with 75:25 blend. Both 90:10 and 75:25 blends showed highest efficiency for the 3rd generation. In most cases. lures treated with 1 mg of blend caught more male moths than these treated with 2 mg of blend.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.116-122
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• 2013

To evaluate the mechanisms of pathogenicity and nonpathogenicity of Bursaphelenchus xylophilus and B. mucronatus isolated in South Korea, we used 4-year-old P. thunbergii seedlings and 20-cm long one-year-old stem cuttings of 5-year-old Pinus thunbergii, and studied distributions and multiplications of pine wood nematodes after inoculation. The distributions of B. xylophilus in the 20-cm pine stem cuttings were not significantly different from that of B. mucronatus. Conversely, the proliferation rate of B. xylophilus on mycelial mats of Botrytis cinerea was significantly different from that of B. mucronatus. The study using 4-year-old P. thunbergii seedlings also showed that B. mucronatus can migrate to distal portions of the pine seedlings the same as B. xylophilus, but the populations of B. xylophilus remaining in the pine seedlings were relatively larger than those of B. mucronatus. Therefore, we concluded that the pathogenicity of B. xylophilus could be strongly influenced by its ability to multiply.

• Mycobiology
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• v.41 no.4
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• pp.245-247
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• 2013

The ambrosia beetle, Platypus koryoensis, is an economically important pest affecting oak trees in Korea. Candida kashinagacola was isolated from galleries of the beetle in oak wood and identified by analyses of morphology, physiological properties, and nucleotide sequence of the large subunit ribosomal DNA. This is the first report on Candida species associated with oak wilt disease vectored by the ambrosia beetle, Platypus koryoensis, in Korea.

• Mycobiology
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• v.49 no.3
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• pp.275-279
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• 2021

A fungus of the genus Kordyana, found on leaves of Commelina communis and C. minor exhibiting white smut-like symptoms, was identified as Kordyana commelinae based on morphological characteristics and two rDNA sequence analyses. We report the novel occurrence of the genus Kordyana in Korea and the association of K. commelinae with the host plant species. As well, we provide the necessary mycological information to resolve species delimitation and taxonomic problems of Kordyana.

• Mycobiology
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• v.48 no.6
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• pp.518-521
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• 2020

Macruropyxis fraxini has been recorded on several species of Fraxinus in China, Japan, Russia (Far East), and North Korea since its first recorded observation as a rust fungus on F. rhynchophylla in Jilin, China, in 1899. In the Korean Peninsula, the rust fungus was first recorded on F. rhynchophylla in 1935, based on four specimens collected at Mt. Kumgangsan, Gangwondo Province, in the North Korean territory. We confirmed this rust in the Korean Peninsula after 82 years. The rust fungus was identified based on morphological characteristics and a molecular phylogenetic analysis. This is the first record of M. fraxini in South Korea.

• Korean journal of applied entomology
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• v.49 no.2
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• pp.159-162
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• 2010

Diprion hani Smith and Cho was first reported as a new species from South Korea in 2007. Major outbreaks occurred in September 2007. Outbreaks were restricted geographically to only three inland areas of central Korea where had previously been reforested with Korean white pine, Pinus koraiensis Seib. & Zucc. The outbreak areas were approximately 50 km in diameter. The sawfly populations decreased drastically in 2008. Environmental factors of the outbreak sites were investigated as a first step to characterize the sites and to understand the population dynamics of the sawfly. During the outbreak in 2007, the average temperature of the sites were $1.3^{\circ}C$ higher than the 30 years average, and the annual precipitation was 384 mm higher than the average from 1971 to 2000. In addition, Monodontomerus dentipes (Dalman), a well-known torymid parasitoid of many sawflies, is reported as a gregarious cocoon parasitoid of D. hani.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.83-91
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• 2003

Methanol extracts from 207 samples of 118 plant species in 44 families were tested for their fungicidal activities against six phytopathogenic fungi. Extracts of Thuja orientalis leaf, Cinnamomum loureirii leaf, Lindera erythrocarpa barks and leaf, Pinus koraiensis wood, Hovenia dulcis wood, Koelreuteria paniculata barks, Styrax japonica wood, Camelia japonica leaf and Cleyera japonica leaf showed very strong fungicidal activity against more than two phytopathogenic fungi at a concentration of 2000 ppm. As a naturally occurring fungicide, these plants could be useful as new fungicidal products against various plant diseases induced by plant pathogens.

• Korean Journal of Medicinal Crop Science
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• v.15 no.6
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• pp.371-390
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• 2007

Arthropod pests were surveyed from 132 herb species of 121 genera in 50 families of 32 orders at herb garden of Sancheong-gun Agricultural Development Technology Center in Sancheong, Gyeongsangnamdo province from October, 2005 to November, 2006. Ninety eight arthropod pests of 86 genera in 44 families of 9 orders were collected. Although less than 5 arthropod pests were collected from each herb, more than 5 arthropod pests were occurred on Hibiscus mutabililis, Peucedanum japonicum, Aralia cordata, Fraxinus rhynchophylla, Angelica decursiva, Rhaponticum uniflorum, Lonicera japonica, Betula platyphylla and Agrimonia pilosa. Out of collected pests, 98.5% of them damaged leaves of medicinal plants. The highest number of arthropod pests was recorded in May representing 36 species of 32 genera in 20 families of 6 orders. Most of them were collected from less than 5 medicinal plants. However, Atractomorpha lata, Dolycoris baccarum, Myzus persicae, and Nysius plebejus occurred on 42., 22, 20, and 15 medicinal plants, respectively. Atractomorpha lata and Myzus persicae had broad host ranges and seriously damaged. Aphis gossypii was dominant insect pest in May compared with Dolycoris baccarum in June. Atractomorpha lata in August and September, and Myzus persicae in October.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.295-301
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• 2020

In this study, we aimed to investigate the changes in the catch rate of Monochamus saltuarius, based on sexual maturation by using aggregation-sex pheromone traps. Ovariole development of caught M. saltuarius females was compared to that of the ones not caught using traps. In a mesh cage set up at the Hongneung experimental forest, we placed a multi-funnel trap with or without an aggregation-sex pheromone lure. M. saltuarius adults, which emerged from pine logs, were grouped in four according to the emergence dates (0, 1, 7, and 10 days after emergence [DAE]). We released beetles into the mesh cage to investigate the catch rate using the traps. In each group, a total of 80 beetles (20 beetles × 4 replications) were tested, making it a total of 320 beetles. Among the four groups, M. saltuarius adults in the 7 DAE group were caught more frequently using the traps, especially with a pheromone lure; the other groups showed a low catch rate. A similar number of female and male beetles were caught using the traps. Regarding ovariole development, all the female adults in the 0 and 1 DAE groups were immature, while those in the other two groups were completely developed. Therefore, aggregation-sex pheromone traps might have a limitation in the prevention of pine wilt disease because of the transmission of pine wood nematode during maturation feeding of newly emerged M. saltuarius adults. However, aggregation-sex pheromone traps can be effective for collecting sexually mature M. saltuarius adults, for the investigation of seasonal occurrence of beetles in forests.