• Korean journal of applied entomology
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• v.60 no.1
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• pp.79-90
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• 2021

Landscape composition and structure are important factors determining biological diversity including pests and natural enemires in agricultural ecosystem. This study was conducted to indentify effect of landscape composition on occurrence of lepidopteran pest population in Geochang, Gyoungdnam. For this, orchard characteristics and management practices were surveyed in 80 conventional apple orchards in Geochang, Korea, along with the monitoring of pest population densities. The landscape features of each surveyed orchard also obtained by extracting information from the public-service map. Grapholita molesta was the most dominat and damaging pest followed by Phyllonorycter ringoniella and Carposina sasakii in trap catches. Adoxophyes paraorana occurrences were low. Farmers spray insecticides and fungicides ap. 12.4 times per year respectively while acaricides were sprayed 2.4 times. Major landscape features such as surrounding apple orchard or paddy field did not influence the pest populations but presence of plum, peach, wild peach, graph, and even abandoned orchards significantly resulted in higher pest population mostly on G. molesta. C. sasakii population was higher in orchards with grape, peach, and P. ringoniella with peach, grape, abandoned orchards and jujube. Results highlight the need of landscape management not only for the rural amenity but also for increasing functional diversity of agroecosystem as well as reducing pest population.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.369-376
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• 2005

Turnip mosaic virus (TuMV) is an infectious viral pathogen on the cruciferous crops, predominantly Chinese cabbage (Brassica campestris subsp. pekinensis) and radish (Raphanus sativus). On the basis of the symptom development in selective differential hosts from indicator host species, Chinese cabbage and Korean radish inbred lines, the representative eight isolates of TuMV were divided into two major groups/or six types. Group I includes Th 1, Ca-ad7, and Cj-ca2-1 isolates, while group II includes the other isolates (rg-pfl, r 9-10, Rhcql-2, Stock and Mustard). According to the molecular phylogenetic analysis, these isolates, however, divided into two groups and two independent isolates. Phylogenetic analysis indicated that four isolates (Tu 1, r9-10, Stock and Rh-cql-2) formed a distinct phylogenetic group, and the other two isolates (Ca-ad7 and Cj-ca2-1) also formed another group. Mustard and rg-pfl isolates did not seem to have any relationship with these two groups. Taken together, these results indicated that virulence differentiation on host plants, molecular phylogenetic analysis of the nucleotide and the deduced amino acid of TuMV coat proteins did not show any relationship. The multi-resistant lines, Wonyae 20026 and BP058 in Chinese cabbage represent valuable genetic materials that can be used for crucifer breeding programs on TuMV resistance, but not in Korean radish.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.305-315
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• 2021

The cotton leafworm, Spodoptera littoralis, is a major pest in Egypt and many countries worldwide, and causes heavy economic losses. As a result, management measures to control the spread of the worm are required. S. littoralis nucleopolyhedrovirus (SpliNPV) is one of the most promising bioagents for the efficient control of insect pests. In this study, a chitinase gene (chitA) of a 1.8 kb DNA fragment was cloned and fully characterized from SpliNPV-EG1, an Egyptian isolate. A sequence of 601 amino acids was deduced when the gene was completely sequenced with a predicted molecular mass of 67 kDa for the preprotein. Transcriptional analyses using reverse transcription polymerase chain reaction (RT-PCR) revealed that chitA transcripts were detected first at 12 h post infection (hpi) and remained detectable until 168 hpi, suggesting their transcriptional regulation from a putative late promoter motif. In addition, quantitative analysis using quantitative RT-PCR showed a steady increase of 7.86-fold at 12 hpi in chitA transcription levels, which increased up to 71.4-fold at 120 hpi. An approximately 50 kDa protein fragment with chitinolytic activity was purified from ChitA-induced bacterial culture and detected by western blotting with an anti-recombinant SpliNPV chitinase antibody. Moreover, purification of the expressed ChitA recombinant protein showed in vitro growth inhibition of two different fungi species, Fusarium solani and F. oxysporum, confirming that the enzyme assembly and activity was correct. The results supported the potential role and application of the SpliNPV-ChitA protein as a synergistic agent in agricultural fungal and pest control programs.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.283-284
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• 2019

• Korean journal of applied entomology
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• v.40 no.1
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• pp.1-4
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• 2001

The American species Melanolophia imitata (Walker) is recorded for the fist time from Korea. The species attacks various coniferous trees in Canada and, in prospect, it can stay a serious pest of forestry in East Asia.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.69-78
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• 1992

The extensive cultivation of new yielding varieties might give some distruption to the rice insect pest complex in Korea The population of Nephottetix cincticeps and Laodelphax striatellus has decreased in number since the extensive cultivation of new varieties, Tongil lines, in 1976. During the last 23 years, the rice insect pest population except for Chilo suppressalis drastically decreased, however, C. suppressalis population increased again in recent years. This tendency seems to be very closely correlated with the cultivation of new varieties, and a lot of fertilizations and insecticides applications.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.143-146
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• 2007

Concerns of entomopathogenic fungi as alternative pest control agents are increasing even though chemical pesticides have been used as the main control agents for pests and diseases in crop production. This study was conducted to test the influence of fungicides and insecticides on an isolate of Lecanicillium attenuatum that was reported to have the pathogenicity against cotton aphid, because fungicides and/or insecticides can apply with mycopesticides simultaneous, before and/or after. Fungicides fenbuconazole+thiram and propineb inhibited the spore germination and mycelial growth of L. attenuatum CS625; dimethomorph and procymidone did not affect spore germination or mycelial growth. The insecticide abamectin, deltamethrin, imidachropride, and spinosad had no detrimental effects on spore germination or mycelial growth. Therefore, these results demonstrated that careful selection of pesticides and fungicides can be applied to the integrated pest and disease control with microbial pesticide.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.45-51
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• 2013

Tropical plants of mango(Mangefera indica), dragon fruit(Hylocereus undatus), and atemoya(Annona cherimola ${\times}$ A. squamosa) are cultivated in Jeju, Korea. A pest survey on those tropical fruits was conducted from 2008 to 2011. Major pests of Mango were thrips, aphid, mealybug, and lepidoptera species. Thrips palmi and Scirtothrips dorsalis were the most important pests in mango fields. T. palmi mainly injured the leaf but S. dorsalis injured the leaf and fruit. Lepidoptera mango pests injured leaves but some larva of Adoxophyes honmai injured fruit surface around the stem. Aphid pests, Aphis gossypii and Myzus persicae, injured the shoots and Pseudococcus kraunhiae occurred on the stem and fruit. Ant species, A. gossypii, and S. litura, were important pests on dragon fruit. Ants and aphid occurred and injured the stem, flower, and fruit. Spodoptera litura larva severely injured the stem. Among the atemoya pests, S. litura and Homona magnanima caused severe damage.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2000.10a
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• pp.69-69
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• 2000

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2001.10a
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• pp.248-265
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• 2001

Recently, agriculture in Korea is seriously depressed by economic globalization and trade liberalization because of low competitive power. Organic farming, which is favorable for small scale agriculture, is expected to be one of alternatives to boost agricultural activities in Korea. Organic agriculture requires systemic developments of new technologies considering the complex biological interaction within the system in connection with high quality and safety standard. The National Institute of Agricultural Science & Technology(NIAST) has been worked on the series of organic farming technologies, including bio-pesticides, pheromone, natural enemies as well as the testings of materials used in organic farming. NIAST will concentrate on the technological development for compromising to the conflict between commodity-oriented and ecological harmony. Research on systemic land and water use, management of plant nutrition, pest and disease control, post-harvest would also be important targets. Integrated efforts among researchers, professors, administrators, farmers, private sectors, and extension workers are substantial for fast technology development and its dissemination. Development and use of these technologies will homely enlighten the Korean organic farming although it may require quite a time and endeavor.