• Korean journal of applied entomology
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• v.53 no.4
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• pp.331-338
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• 2014

Cystatins (CSTs) are reversible and competitive inhibitors of C1A cysteine proteases, corresponding to papain-like cathepsins in plants and animals. A viral CST (CpBV-CST1) was identified from a polydnavirus, Cotesia plutellae bracovirus (CpBV). Our previous study indicated that a transient expression of CpBV-CST1 interfered with immune response and development of Plutella xylostella larvae. To directly demonstrate the protein function, this study produced a recombinant CpBV-CST1 protein (rCpBV-CST1) using bacterial expression system to determine its inhibitory activity against cysteine protease and to assess its physiological alteration in insect immune and development. The open reading frame of CpBV-CST1 encodes a polypeptide of 138 amino acids (${\approx}15kDa$). rCpBV-cystatin protein in BL21 STAR (DE3) competent cells containing a recombinant pGEX4T-3:CpBV-CST1 was over-expressed by 0.5 mM IPTG for 4 h. In biological activity assay, the purified rCpBV-CST1 showed a significant inhibition against papain activity. It inhibited a cellular immune response of hemocyte nodule formation in the beet armyworm, Spodoptera exigua. Moreover, its oral administration retarded larval development of the diamondback moth, Plutella xylostella in a dose-dependent manner. These results suggest that CpBV-CST1 may be applied to control insect pest populations.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.58-64
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• 2015

The black cutworm, Agrotis ipsilon (Hufnagel) is a major insect pest of economic crops including turfgrasses on golf courses. The entomopathogenic nematode, Steinernema carpocapsae GSN1 strain (ScG), a Korean isolate, is an effective biological control agent for soil dwelling and greenhouse insect pests in Korea. In addition, ScG is commercially produced in Korea. We conducted laboratory, greenhouse, and field trials to evaluate efficacy of ScG against black cutworms in turfgrasses. A rate of 63 infective juveniles (Ijs) per larva killed >90% of $3^{rd}$ instars feeding in cups of artificial diet within 3 days. In greenhouse trials against cutworms feeding in pots of turfgrass, efficacy of ScG was higher against $4^{th}$ instars than against $2^{nd}$ instars (90.0 vs 81.2% mortality, respectively, at $2,000Ijs\;pot^{-1}$) in perennial ryegrass, and higher against $3^{rd}$ instars in creeping bentgrass, Agrostis palustris than in zoysiagrass, Zoysia japonica (96.7 vs 52.5% mortality at $100,000Ijs\;m^{-2}$) in pot. The corrected mortality of $4^{th}$ instar was 79.9% at the rate of $100,000Ijs\;m^{-2}$ in the creeping bentgrass in the field. So ScG could be used as biological control agent against black cutworm in turfgrass of golf courses.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.387-401
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• 2017

This study was performed in order to investigate disease, insect damage, growth and yield characteristics of green maize by organic paddy-upland rotation system. This experiment also was to select optimum variety for organic paddy-upland rotation cultivation. This experiment was conducted at Anseong-si Gyeonggi province of Korea in 2016. The varieties used in this study are green maize of total 8 varieties. Green maize was planted at rotational upland field and continuing upland field and tested for comparison. In case of average occurrence of 4 major disease for green maize, rotational upland field was higher than that of continuing upland field. Heukjinjuchal and Daehakchal were the lowest occurrence by less than 2% among 8 varieties. Average damage of 8 varieties by Ostrinia furnacalis larva, which is the main pest in green maize was higher in rotational upland field than that of continuing upland field. Chalok 4 and Heugjeom 2 were judged to be resistant varieties to 4 major disease among 8 varieties. The average yield of green maize per 10a in rotational upland field decreased to 85% level of continuing upland field and Chalok 4 showed the highest yield by 789.0 kg/10a among 8 varieties. The most suitable varieties in organic paddy-upland rotation system were judged to be Chalok 4, Heukjinjuchal and Heukjeom 2.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.145-149
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• 1997

Occurrence pattern of major insect pests on 7 recommended potato cultivars in Korea was investigated from sowing to harvesting time at Kangneung and Daegwallyung experiment fields in 1996. Green peach aphid (Mym persicae Sulzer), potato aphid (Macrosiphum euphorbiae Thomas) and beet armyworm (Spodoptera enigua Hubner) were the major insect pests on potato leaves, and wireworm (Selatosomus puncticollis Mot.) was the major pest on tubers. There was a slight difference of average number of aphids per 50 leaves among cultivars; ranged from 22.7 on cv. Dejima to 46.3 on cv. Superior. Numbers of leaves damaged by beet armyworm larvae on cv. Shepody and cv. Jopung were 11.0 and 14.3, and these cultivars are thought to be resistant against the larvae infestation. However, degree of damage on cv. Dejima and cv. Namsuh was higher 10 times than cv. Shepody and cv. Jopung. In wireworm, the percentage of damaged tubers on cv. Irish Cobbler was lowest of 8.1%, and followed by cv. Superior, cv. Dejima, cv. Jopung, and cv. Atlantic. Whereas, those on cv. Namsuh and cv. Shepody were significantly high of 50.0% and 46.8%.

• Korean journal of applied entomology
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• v.58 no.2
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• pp.143-149
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• 2019

This study was conducted to examine the attractiveness of yellow sticky trap (YST) for insect pests by the angle of inclination of the trap surface. In strawberry farms with high bed system, YSTs were installed to attract insect pests in vertical direction with one surface, horizontal direction with upper and under surface, and angle of $45^{\circ}$ with upper and lower sticky surface. Thrips (Frankliniella occidentalis in dominance) and Sciaridae (Bradysia agrestis in dominance) species were more attracted on upper surface of $45^{\circ}$ angle trap, vertical surface and upper surface of horizontal trap than on lower surface of $45^{\circ}$ angle trap or horizontal trap. Cicadellidae (Empoasca vitis in dominance) species were caught more on vertical surface and upper surface of $45^{\circ}$ angle trap than on other traps. There were no specific trend in capture of aphid (Aphis gossypii in dominance) and white fly (Trialeurodes packardi in dominance) species among traps, probably because of a low density of the pest species.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.281-293
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• 2020

The Korean thistle (Cirsium setidens) is grown in Gangwon province as a food ingredient called gondre. Based on regular monitoring of Korean thistle cultivation, we detected local outbreaks of a stick insect causing severe damage. Here we report the identification of the stick insect and its ecological characteristics. The survey involved 3 farms located in Jeongeon-gun, Gangwon province and lasted from May 28 to October 1 in 2019. According to morphological and DNA analyses the stick insect was identified as Ramulus koreanus Kwon Ha and Lee. a member of the family Phasmatidae. Its outbreak in the Korean thistle farms was observed from June 11 to August 22 with peak density on July 23. Spatial distribution analyses, using Taylors power law and Greens index showed that R. koreanus was uniformally distributed. Food consumption rate of Korean thistle leaves was estimated as 60.98±4.35 ㎠/day/adult. The main food plants were identified as Juglans mandshurica and Aronia melanocarpa. Further study needs to pursue the mechanism of the outbreak and its possible impact on agricultural and forest ecosystems. Additionally, means to relieve crop damage need to be identified.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.333-339
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• 2020

Pheromone-based techniques are becoming a viable strategy of insect pest management as facilitated by the exponential increase in numbers of pheromone identifications from many insect pests. This is the report on the efficacy of pheromone-mediated chemical communication disruption (PCD) technique against the Korean population of smaller clearwing moths, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae) using its female sex pheromone component, (Z, Z)-3, 13-octadecadien-1-ol. The PCD trials were carried out four times during 2016 and 2017 in persimmon orchards located at Suncheon and Jinju Cities in Korea, and the PCD efficacy was expressed as the mean differences in the seasonal catches of S. tenuis males in the PCD and control plots. The seasonal male moth catches in monitoring traps installed in the PCD plots were significantly lower as compared with those installed in the control plots. Consequently, the PCD efficacy in the experimental orchards ranged from 95.2-100% with an average efficacy of 98.8 ± 1.2%, revealing a future possibility of pheromone-based management of S. tenuis.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.229-238
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• 2022

Animal pollination is an important ecosystem service provided mostly by diverse insect groups such as bees and hover flies. Maintaining agricultural productivity and securing the nutritional balance are closely tied to human wellbeing. This study aimed to estimate the pollination dependent food production in Korean agricultural system. Crop production data were obtained from Korean statistical information service (KOSIS) data of 2015. By implementing pollination dependency, crop production and market price, contribution of insect pollination to crop production increase were estimated from total 71 crops including 12 cereals, 19 fruits, 18 field vegetables, 13 greenhouse vegetables and 9 specialty crops. Mean pollination dependency of all crops were 29.2% and it was higher on fruits, specialty crops and greenhouse vegetables as well, but low (7.5%) in cereal crops. Pollination dependent (PD) production was estimated as 17.8% of total agricultural crop production with the economic value of 6,850 (6,508-7,193) billion won. Especially, PD production of greenhouse vegetables accounted 49.2% followed by fruits of 42.9%. Even specialty crop also showed higher PD production (35.9%). It was obvious that pollination is the vital service for agricultural production as well as nutritional security in Korea. Further protection and enhancing the pollination service were discussed with integrated pollinator-pest management (IPPM) strategies.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.135-142
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• 2015

The American cockroaches, Periplaneta americana L. was the most important worldwide pest species. It has been an public health problems. We were determinated life cycle and extraction of crude extracts by chemical reagents from cockraches (P. americana L.). The extracted crude solution has been antibacterial activity to gram negative bacteria (Pseudomonas aeruginosa, $6.44{\pm}1.03mm$), gram positive bacteria (Bacillus subtilis, $1.88{\pm}0.40mm$), and fungus (Candida albicans, $5.61{\pm}0.57mm$) using radial diffusion assay. We were analysed of up-regulation of Glutathione-S-transferases (GSTs) stimulation, indicating that antioxidantial protein from various classes are simultaneously expressed in a single insect upon infection or injury. The gene from Periplaneta americana L. were cloned, analysed sequence, and measured protein expression by Real Time PCR (Polymerase Chain Reaction).

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.601-615
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• 2013

This study was conducted to compare the community structure and biodiversity of arthropods between conventional and organic red pepper fields. A total of 36 species of 24 families belonging to 10 orders from collected 28,718 arthropods; 6,901 individuals from conventional field and 21,871 individuals from organic field. A number of species comprising arthropod community was same in both fields as 32 species. Species richness of Diptera was the highest in conventional field and that of Hymenoptera and Colembolla was the highest in organic field. Abundance of Frankliniella intonsa was the highest regardless of farming method. Helicoverpa assulta was dominant in conventional field, and Homidia mediaseta, Diptera sp. 4 and Pardosa astrigera were dominant in organic field. Diversity of community on the ground was higher in organic field and statistically different. Similarity of arthropod community showed difference with 34.07% on the ground and 26.95% in the plant above ground. In the ecologically functional guild: species richness of general, pest and parasitoid of natural enemy groups in the plant above ground were statistically different and pest and parasitoid groups were higher in organic field, abundance of predator group of natural enemy on the ground was 2 times higher in organic field and statistically different and diversity of general and parasitoid groups in the plant above ground were statistically different. In the relative occupancy rate, pest group was the highest in conventional field and decomposer group was the highest in organic field. The results of present study is considered to provide useful information of arthropod community for developing efficient insect pest management in organic farming.