• Korean journal of applied entomology
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• v.51 no.4
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• pp.405-410
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• 2012

This study is conducted to develop a new method of early occurrence monitoring for Aculops lycopersici Massee (Acari: Eriophyidae), a major pest in tomato. A. lycopersici causes damage to plants such as curling of leaflet edges, followed by leaflet bronzing. As feeding continues by the mites, the plant takes on a russeted, wilted appearance, eventually culminating in leaflet desiccation and finally plant death. Fruit damages in tomato were shown when the density of mites was very high. Also, A. lycopersici caused more damage to unripe fruits than ripe fruits. The time taken to detect A. lycopersici on green label sticker was 7.0 seconds, the shortest. Blue, orange and white label stickers took 17.1, 19.8 and 12.3 seconds respectively. The permeable microscope with side illumination was useful in observing A. lycopersici on label stickers. A. lycopersici began to occur in late-April and the density of the mites increased rapidly after mid-May. The density peaked in mid to late-June, and decreased after late-June. A. lycopersici was observed on lower stems 20 days after the release of mites and observed on higher stems 60 days after. The peaked densities were observed on stems 40 and 60 days after and on leaf 80 days after. The label sticker is enough to monitor early occurrence of A. lycopersici in tomato cultivation facilities.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.167-173
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• 2021

Sweet potato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an insect pest with sucking mouth part and globally attacks diverse crops and vegetables. Since first reported in 1998, it is now widely spread in many regions in Korea. Due to insecticide resistance, it is necessary for optimal control of the whiteflies to select effective insecticides with precise insecticide resistance monitoring. In this study, B. tabaci individuals were collected from 12 regions in 7 provinces of Korea from June to September in 2020. Using these field populations, insecticide resistance levels were monitored using a residual contact bioassay along with molecular markers. Bioassay results revealed that B. tabaci possessed high levels of resistance to five insecticides exhibiting different modes of action: dinotefuran, spinosad, emamectin benzoate, chlorfenapyr, and bifenthrin. In addition, quantitative sequencing in target sites of organophosphate and pyrethroid insecticides revealed that point mutations reached to saturated or near-saturated levels across the country. This suggests that insecticide resistance management is required for effective control of B. tabaci populations in Korea.

• Korean journal of applied entomology
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• v.62 no.2
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• pp.69-78
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• 2023

The currently implemented Positive List System, sales manager training, and pesticide sales record systems focus on the safety of determined pesticide use, but the proposed agrochemical pharmacist (AP) system aims accurate diagnosis and reasonable prescription. In this study, 81% of famers claimed expert assistance for purchasing and applying pesticides, and 42~86% of sales managers insisted on the strengthening expertise in diagnosis and prescription. In the institutionalization of AP, a special implementation guideline is essential to embrace the present sales managers with long experience. Sales managers of commercial and agricultural cooperatives recognize the qualifications of agrochemical pharmacists as a strategy to differentiate themselves from competitors, and increase sales through market positioning of "pesticides prescribed by trustworthy agrochemical pharmacists", not sales managers anymore.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.117-124
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• 2023

The management of Ricania spp. is difficult because this pest has a wide host range and diverse habitats such as agricultural, suburban, urban, and forested areas. However, the researches for Ricania spp. management have been focused on only agricultural crops. Thus, it is required to determine the arboreal host preference of Ricania spp. at the surrounding areas of the farms to increase its management efficiency. To determine its host preference at arboreal plants, we reviewed the previous studies and investigated the densities of Ricania spp. at woody plants with high ecological importance but insufficiently studied. This study identified 120 species in 53 families of arboreal hosts of Ricania spp. Only Cornus officinalis and Styrax japonicus were preferred by all developmental stages of Ricania spp. The host preference of Ricania spp. was changed according to its developmental stages. This phenomenon would be caused by that each developmental stage of Ricania spp. would prefer different parts of woody plant, and require different nutrients for its survivor and reproduction. These results of this study could be helpful to make a plan of comprehensive management strategies for Ricania spp.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.23-29
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• 2013

This study was conducted to clarify effects of weed control methods on damages from agricultural chemicals of pear trees, growth of weeds and states of pear trees after treating pear orchards with different methods of weed controlling, density of GLU and application times. The growth and occupation rate were investigated after 10, 20 and 40 days of weeding treatment. According to a result of the first treatment conducted when weeds in the lower parts of crown in a pear orchard began to grow and grew about 20 cm, unwoven cloth covering showed the highest control value with 100% in all 14 kinds of grasses. In comparison, Stellaria aquatica and catchweed bedstraw showed 96.7% and 97.3% respectively in the 20 DAT investigate after the first treatment of GLU 540 g a.i. ha-1 and the high control value of 100% in other all kinds of grasses. According to an investigation of stalk enlargement, length of new shoot and the number of new shoot made to know differences in tree growth following treatment of the lower part of crown, to use weed killers two or three times a year or to eliminate grasses with machines have positive effects on cross growth of pear trees.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.3
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• pp.267-274
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• 2017

Recently, several researches have been studied on agricultural automation system according to convergence of IT technology with agriculture. An automatic control system of the growth environment in crops is one of the these researches. The controls of damages caused by diseases and insects pest in crops are mainly carried out by manual mode or semi-automatic mode because of farmer's concerns for poor efficiency. But, this situation needs to be improved because it occurs various problems, such as human exposure to toxic pesticides, environmental pollution and waste due to drug overuse. In order to solve these problems, we developed an automatic quantity control system which based on the amount of pesticides for area under cultivation. The amount of pesticides is calculated according to the manufacturer's instruction for pesticides. To verify the effectiveness of our developed automatic system, we also compared with the systems of manual mode and the semi-automatic mode. The experimental results of a pest control performance of an automatic quantity control system showed that automatic system can reduce overuse of drugs. These results suggested that it can be expected to replace the existing system, with equivalent effectiveness to the manual mode.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.275-278
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• 2008

Ginseng stem fungus gnat, Phytosciara procera, is reported as a ginseng pest for the first time. It is new to science that a member of the family Sciaridae is a ginseng pest. In our observation, larvae of the gnat can penetrate the stem of ginseng, and then they make a shaft in shoot and root. Number of adults captured by yellow sticky traps were peaked in twice, from late July to early August and from late August to early September. In a ginseng field, 29.7% of ginseng damaged by Phytosciara procera is also infected by bacterial disease caused by Erwinia carotobora. However, there is a possibility on environmental-friendly control, as a result of decreasing effect of damage over 85% when remaining a part of berry on peduncle than tatally remove.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.7-14
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• 2000

Methanol extracts from 21 grains were tested for fungicidal activities against six phytopathogenic fungi and for insecticidal activities toward five insect pests in a greenhouse. The efficacy varied with both the plant pathogen/insect pest and grain species used. Potent fungicidal activity at 5 mg/pot, were produced from extracts of Elymus sibiricus and Hordeum vulgare var. nudum against Pyricularia grisea and Erysiphe graminis and these of Sesamum indicum (W) and Triticum aestivum against Puccinia recondita and Erysiphe graminis. At 2,500 ppm, potent insecticidal activities were exhibited from the extracts of Fagopyrum esculentum against Myzus persicae and Ischaemum crassipes, and these of Oryzo sativa var. glutinosa, Panicum miliaceum, Setaria italica, Sorghum bicolor, and T. aestivum against Tetranychus urticae. All grain extracts revealed weak or no fungicidal and insecticidal effect against Phytophthora infestans, Plutella xylostella and Spodoptera litura. As a naturally occurring fungicide and insecticide, grain-derived materials described could be useful as new fungicidal and insecticidal products against phytopathogenic fungi and insect pests.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.361-372
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• 2018

Migratory insect pest populations migrate from the southern China to Korea through jet streams. In Korea, 5 major migratory insect species are important, i.e. Nilaparvata lugens, Sogatella furcifera, Laodelphax striatellus, Cnaphalocrocis medinalis and Mythimma separate, which are damages to the major crops, rice. This study was conducted from late July 2016 to early September 2016 and from July 2017 to August 2017 in rice paddy of Jeolla-province. C. medinalis and M. separata collected using pheromone traps, while N. lugens, S. furcifera and L. striatellus collected using 3 methods (visual surveys, sweeping surveys, sticky traps). SADIE (Spatial Analysis by Distance IndicEs) among geostatistics was used to analyze migratory insect pests. SADIE was used to analyze spatial distribution and index of aggregation $I_a$, index of clustering $V_i$, $V_j$ were used to investigate the spatial distribution. Also, the clustering indices were mapped as red-blue plot. C. medinalis and M. separata showed different distribution based on SADIE spatial aggregation analysis and red-blue plot analysis. Initial spatial distributions of L. striatellus and other planthoppers were differed for sampling location and time.

• Korean Journal of Environmental Agriculture
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• v.38 no.1
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• pp.23-33
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• 2019

BACKGROUND: The golden apple snail(GAS, Pomacea canaliculata Lamarck) is an invasive freshwater snail. It has occurred 34 years since the introduction of the GAS to the Korea. The GASs have been used recently for weed control in wet rice cultivation. The GASs'adaptability to the environment of GAS has been improved and the GASs devour the young stage of the crops as well as weeds. METHODS AND RESULTS: We surveyed the survival area of the snails throughout the country during the winter seasons from 2000 to 2017 and crop damage due to GASs in 2017. Local maximum, minimum, and average air temperatures were monitored daily. The surveyed regions for the survival of the GASs in winters were Gangjin, Goheung, Shinan, Haenam, Gimhae, Haman, Busan, Jeju, and Seogwipo. The survival durations at low temperatures were 12 hours at $-5^{\circ}C$, 1 day at $-3^{\circ}C$, 2 days at $-1^{\circ}C$, 10 days at $0^{\circ}C$, and over 30 days at $3^{\circ}C$. The eggs of GASs were not able to overwinter. The overwintering condition of the GAS needed a water depth of 10-20 cm with well formed mud. Crop damages caused by the overwintering GASs occurred in rice and water dropwort. CONCLUSION: The overwintering GAS was first identified in Haenam, South Korea 2000 after introduction of the GAS. The overwintering area of GAS expanded to the mid-southern parts of Korea. We propose that it has not yet become a pest to rice or any other crop.