• Korean Journal of Environment and Ecology
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• v.22 no.2
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• pp.75-82
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• 2008

This study was carried out to investigate the distribution of forest insect pests of Dobongsan in Bukhansan Nation Park. A total of 76 species of forest insect pests belonging to 29 families under 5 orders were collected in these areas: 24 species 9 families in Lepidoptera; 23 species 9 families in coleoptera; 20 species 4 families in Homoptera; 6 species 5 families in Hemiptera, and 3 species 2 families in Hymenoptera. These were 66 species of 28 families under 5 orders found in Songchoo-gol, and 41 species of 19 families under 5 orders found in Hoeryong-gol. Key foest insects for control pests were confirmed to be Platypus koryoensis, Arcte coerulea, Erannis golda, and Isyndus obscurus was classified predaceous natural enemy.

• Korean journal of applied entomology
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• v.54 no.2
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• pp.111-114
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• 2015

We report three lepidopteran insect pests of non-astringent persimmon leaf for the first time from Korea; Hypocala deflorata (Noctuidae), Teliphasa elegans (Pyralidae), and Cuphodes diospyrosella (Gracillariidae). Larvae of these species were collected from an organic farming or abandoned persimmon orchard in Changwon and Jinju cities, Gyeongnam province, and reared for the identification in the laboratory. Some information, such as collection records, hosts, simple morphological characteristics, and ecology were introduced for each species.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.57-63
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• 2003

Accurate forecasting of occurrence time and abundance of insect pests is essential for developing technology of integrated pest management system. Digital image processing algorithms were utilized to automatically recognize rice planthoppers which are major insect pests in the rice cultivation field and were subsequently used to estimate densities in the field for efficient forecasting of insect pests. To the images taken in the rice field, image decomposition, top-hat transformation, threshold, and minimum and maximum filter were implemented for patterning individually the brown planthopper specimens attached at the bottom area of rice stems. In average 95.8cio of images were correctly recognized for estimating densities by the developed system, and the recognition rate was higher than that obtained from direct observations by experienced observers. Furthermore, the size of the recognized specimens was measured and was used for estimating the age structure in the observed brown planthopper populations.

• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.334-337
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• 2005

Pine wood nematode isolates from Haman, Gyoungsangnam-do were cryopreserved with three different cryoprotectants (glycerol, ethylene glycol and dimethylsulfoxide), Nematode Growth medium (NGM) and M 9 buffer solution, respectively, and then survival rate, reproduction ability, and pathogenicity of stored nematodes were compared. Survival rates of juvenile was excellent in 15% glycerol solution as $72{\pm}5.3%$. The survival ability of nematodes at juvenile stage was more efficient than that of nematodes at adult stage. Pre-incubation treatment at $4^{\circ}C$ before storing in liquid nitrogen didn't affect the survival ability of pine wood nematode. When the reproduction ability of nematodes was confirmed on Botrytis cinerea agar plates at $28^{\circ}C$ incubator, there was no difference between cryopreserved and non-cryopreserved. Pathogenic ability of cryopreserved nematodes was also evaluated and confirmed by artificially inoculating them on 2-year old red pine seedlings.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.340-346
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• 2016

To understand how Bursaphelenchus xylophilus kills pine trees, the differences between the effects of B. xylophilus and B. mucronatus on pine trees are usually compared. In this study, the migration and attacking ability of a non-pathogenic B. mucronatus in Pinus thunbergii were investigated. The distribution of B. mucronatus and the number of dead epithelial cells resulting from inoculation were compared with those of the pathogenic B. xylophilus. Although B. mucronatus is non-pathogenic in pines, its distribution pattern in P. thunbergii was the same as that of B. xylophilus. We therefore concluded that the non-pathogenicity of B. mucronatus could not be attributed to its migration ability. The sparse and sporadic attacking pattern of B. mucronatus was also the same as that of B. xylophilus. However, the number and area of the dead epithelial cells in pine cuttings inoculated with B. mucronatus were smaller than in those cuttings inoculated with B. xylophilus, meaning that the attacking ability of B. mucronatus is weaker than that of B. xylophilus. Therefore, we concluded that the weaker attacking ability of B. mucronatus might be the factor responsible for the non-pathogenicity.

• The Plant Pathology Journal
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• v.29 no.3
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• pp.344-349
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• 2013

Intraspecific variation in morphometry of pine wood nematodes Bursaphelenchus xylophilus and B. mucronatus in relation to geographical locations in South Korea was investigated using morphometric characters (body length, a, b and c ratio, stylet length, and spicule length for a male nematode and V (%) value for a female nematode). B. xylophilus was isolated from Pinus thunbergii in Jinju (1998), Ulsan (2000), Yangsan (2000), Mokpo (2001) and Jeju (2004), and from P. densiflora in Gumi (2001). B. mucronatus was isolated from P. thunbergii in Jinju (1991) and from P. densiflora in Milyang (2001). The body length of male and female B. xylophilus had the highest coefficient of variability and showed significant differences among geographical locations. The V (%) value for female B. xylophilus showed the lowest coefficient of variability, changing little with geographical area and host plant. All morphometric characters in B. mucronatus except for stylet length and female body length showed no significant differences between locations or hosts, suggesting they may not be affected by geographical area or host plant.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.117-126
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• 2008

Nine species of Curculionidae, Pimelocerus elongates (Roelofs, 1873), Phylaitis maculiventris Voss, 1958, Egiona picta (Roelofs, 1875), Cryptorhynchus electus (Roelofs, 1875), Rhadinopus confinis Voss, 1958, R. sulcatostriatus (Roelofs, 1875), 1962, Deiradocranus setosus (Morimoto, 1962), Rhadinomerus annulipes (Roelofs, 1875), and R. maebarai Chujo et Voss, 1960 are recorded for the first time in Korea. And the distribution of the species of Shirahoshizo hiurai Morimoto to Korea which its distribution was unclear is confirmed with this report. Habitus photos and descriptions of the species are given.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.51-62
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• 2022

Numerous insect pests threaten the Korean orchard industry through feeding on various tissues of fruit trees. Generally, the control of economically important orchard pests is based on the use of chemical insecticides. Owing to growing concerns regarding the environmental and human health effects of insecticides, environment-friendly pest control strategies are urgently needed. Pheromones of orchard pests could lead to an environmentally safe control system based on mating disruption or mass trapping. This review summarizes the functions and compounds of known pheromones from 51 orchard pests in Korea. The pheromones identified to date from 14 species in the families Miridae, Aphididae, Diaspididae, Pseudococcidae, Rutelidae, Cecidomyiidae, and Eurytomidae and 26 species in the order Lepidoptera are female-produced sex pheromones that attract only males. In contrast, all known examples for 11 species in the families Alydidae, Pentatomidae, Thripidae and Cerambycidae are male-produced aggregation pheromones that attract both sexes. Research on pheromones in new pests, kairomones in key orchard pests, mating disruption dispensers to generate prolonged release of the pheromones, and trap design and trap location for mass trapping will be required for the expanded use of pheromones and other semiochemicals in orchard pest management in the future.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.153-164
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• 2017

Gene silencing using double-stranded RNA (dsRNA) has been widely used in functional genomics in biological organisms. Its principle stems from RNA interference (RNAi), a post-transcriptional control of gene expression. Suppression of specific gene expression using dsRNA may give significant lethal effect. Insect pest control exploits this molecular process to develop novel insecticides using specific dsRNAs. This review explains core principles of RNAi using dsRNA. Then it illustrates various examples to control insect pests using dsRNAs. It also discusses limitations to control insect pests using dsRNAs. Finally, it provides several breakthroughs to develop dsRNA insecticides.

• Journal of Ecology and Environment
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• v.47 no.4
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• pp.250-260
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• 2023

Background: Crabgrass (Digitaria ciliaris, Poaceae) is a globally distributed weed, including in Afro-Eurasia, America, and Australia. As a highly gregarious plant, crabgrass is an important habitat for a diverse array of insects, and a potential habitat for agricultural pests. To compare the insect communities associated with the crabgrass community, insects were sampled using sweep sampling (100 sweeps per sample) at five sites, including Daejeon (Daejeon and Gap rivers), Anseong, Namhae, and Inje, with a focus on the Daejeon River. Results: A total of 5,888 individual insects belonging to eight orders, 42 families, and 115 species were collected from the five sites. Both the number of species and individuals of Hemiptera were the highest at all of the sites. In the present study, 73% of the insect population fed on D. ciliaris as a host plant. The dominant species in the D. ciliaris community was Laodelphax striatellus (Delphacidae), being ubiquitous at all the sites which showed a high abundance of rice pests in the communities and the suitability of D. ciliaris as an alternative host plant for them. The Shannon-Wiener diversity index was highest in Inje on 17 September (2.88), and the Chao1-bc diversity index was highest in the Gap River on 5 September (80). The sampling efficiency of 100 sweep samples (sample coverage) was calculated to be as high as 90%. The results of the samples taken from September to November in the Daejeon River showed that the number of species and individuals decreased gradually over time, and the number of dominant species decreased sharply between September and October. Similarity analysis indicated that sampling dates that were closer together yielded sampled assemblages with higher faunal similarity. In addition, in each sampling, the difference in the minimum temperature during the two-week period prior to sampling and faunal similarities were negatively correlated. Conclusions: This study provides foundational data that could enhance our understanding of insect diversity in D. ciliaris. The data can facilitate ecological conservation and management of Korean grasslands generally, as well as identification of potential pests that may disperse from D. ciliaris communities to nearby farmland.