• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.569-576
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• 2023

An agricultural drones are gradually increasing in utilization due to economic efficiency, and consist of a main frame in charge of flying spray system in charge of moving pesticide to control targets. Therefore, the environment and characteristics of crops should be considered when controlling pesticides using drones and conditions such as systematic flying altitude of flight, speed, and spray time should be changed accordingly. However, pest control work using agricultural drones has different spray effects depending on level the operation proficiency and spray impact. In addition, there are variations in operating standards and control efficiency for agricultural drones, which hinder the distribution of agricultural control drones in the field of pest control work. Therefore, this study attempts to identify the spraying characteristics of agricultural drones, apply the effective spraying time, interval and experimentally verify the system that can calculation of spray area compared to previous studies. Through this experimental verification, it is intended to apply the optimal control process by minimizing the obstacles to pest control work by applying the operation method and systematic figures to agricultural drones.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.345-349
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• 2015

The pest species occurring on the aboveground parts of Phalaenopsis orchids were studied for a period of two years (Aug. 2013 to June 2015) at 9 Phalaenopsis farms in Korea. In total, 10 species of insect pest were identified : Tenuipalpus pacificus Baker, Tyrophagus putrescentiae Schrank, Frankliniella occidentalis Pergande, Frankliniella intonsa Trybom, Thrips tabaci Lindeman, Scirtothrips dorsalis Hood, Pseudococcus dendrobiorum Williams, Pseudococcus longispinus Targioni Tozzetti, Coccus hesperidum L., Limax marginatus $M{\ddot{u}}ller$. T. pacificus occurred in most of the farms surveyed in this study (6). The observation frequency of T. pacificus and F. intonsa were highest, they were observed in 10 out of 96 surveys. Although P. longispinus was only observed to occur on two farms, their observation frequency (9 observations, 9.4%) and density (2-289 per 20 plants) were high. Thus, it seems that T. pacificus, F. intonsa, and P. longispinus are the major pests affecting Phalaenopsis orchid farms in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.1
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• pp.37-47
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• 2023

The black cutworm, Agrotis ipsilon (Hufnagel), is an important crop pest worldwide that feeds more than 80 plant species including cabbage, potato, maize, wheat and bean, and this moth is a typical pest attacking underground parts of crops. It has been known in farm booklets that the larvae of A. ipsilon overwinter in the soil in Korea, but no definitive data exist yet. This study was conducted to evaluate that the specific appearance time of A. ipsilon observed actually in the field could be explained when we assumed that this pest overwinters in a form of larvae or pupae. Degree day-based phenology models were applied for tracking forward or backward to find the predicted developmental stage which developed at a specific stage found in the field. As a result of the analysis, it was confirmed that an initial population could be established in a group that does not overwinter as larvae or pupae in Korea. In other words, the appearance of adults in early March to April could not be explained by the presence of domestic overwintering populations. Populations that overwinter as larvae or pupae in Korea were able to emerge as adults in June to July at the earliest. Therefore, the group of adults appearing in early spring is highly likely to be a population that migrated from outside Korea. Taken together, it was estimated that the colony of A. ipsilon in Korea would be formed by a mixture of a migrant population through long-distance migration and a overwintering population.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.58-62
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• 2017

The two-spotted spider mite (Tetranychus urticae) has sustained damage on more than 200 host plants worldwide. Many farmers have relied on chemical acaricides to control mite, but the abuse of acaricides has caused serious resistance to mite. To overcome this problem, microbial control using entomopathogenic fungi have been studied. Entomopathogenic fungi have been an important role against the control of pest, and most of their culture products have been demonstrated to have virulence against pest population. In this study, we evaluated and compared the virulence of culture filtrates, aerial conidia and blastospores of selected Metarhizium anisopliae 4-2 and Beauveria bassiana 2R-3-3-1, respectively, among two-spotted spider mite-pathogenic fungi. As a result, the virulence was confirmed in all treatments, and the accumulated mortality rates were between 77 and 100% within 7 days. Especially, treatment with the fungal culture filtrate alone exhibited quite high virulence, and combined treatment with aerial conidia or blastospores enhanced activity. However, the median lethal time of treatments was not significantly different. When two isolates were compared, M. anisopliae 4-2 showed higher virulence than B. bassiana 2R-3-3-1. These results suggest that the selected two fungal isolates and their culture products could be used effectively for the control of two-spotted spider mite.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.543-550
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• 2006

Distribution patterns of two pine sawyer species (Monochamus alternatus which is the main vector insect and M. saltuarius which is the potential insect vector of the pine wood nematode) were investigated in Korea. The data were collected at 89 study sites which were chosen to cover the whole region of South Korea. The selected pine trees were killed in early April and left for I year in the pine stands to be egg-laid by the pine sawyers. Emergence of the beetles from the dead pine trees was checked from early April to late July. M. saltuarius was the most abundant in the mid to northern areas of South Korea, whereas M. alternatus in Jeju-do, southernmost island of Korea. Considering temperature distribution patterns in areas where the two species occur, their thermal distribution boundary may be formed around $13.2^{\circ}C$ of annual mean temperature. The hypothesized distribution map of the two Monochamus species under the invasion of pine wilt disease is suggested on the base of thermal distribution of Korean peninsula.

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.243-245
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• 2014

To evaluate light-emitting diode (LED) as potential attractants for Bemisia tabaci adults, attractiveness of white and yellow LED traps were investigated in greenhouse. The yellow LED trap showed the most attractive to B. tabaci adults, followed by a similarly attraction to the white LED trap, whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white LED traps could be used for environment-friendly insect pest control.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.125-132
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• 2003

Uzi fly (Exorista bombycis Louis) is one of the major larval endo-parasitoid of silkworm (Bombyx mori). It causes extensive damage to sericulture industry. The application of synthetic organic pesticides has tremendous impact on minimizing pest population but their overuse and frequent misuse and high sensitivity towards the silkworms, has forced the entomologists to search for alternatives to chemical control, which is safe to silkworm, environment and farm workers. Biological control continues to offer exciting possibilities for the control of fly pest population. It is environmentally safe alternative to chemical control and offering a long-term protection. Several potential hymenopteran parasitoids have been screened. Among successful natural enemies, Nesolynx thymus, Trichomalopsis apanteloctena, Trichopria sp., Brachymeria lasus, Pediobius sp., Spalangia sp., Spilomicrus karnatakensis and Dhirhinus sp. are important. It is essential to predict accurately the efficacy of these natural enemies in a new habitat prior to its introduction. The important desirable attributes of these potential parasitoids viz., host searching capacity, specificity, power of increase and fitness and adaptability of the parasitoid in new environment has been recorded. Results of the host parasitoid interaction indicate that the aging of the host function as a factor that influence the host finding efficiency of the parasitoid. It is highly scored with 15-20 hrs old pupa of the host. However, aging of the parasitoid does not significantly affect it. The sex ratio is female biased which is advantageous from biological control point of view, Biological suppression methods involving conservation and utilization of natural enemies have been discussed in detail.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.179-184
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• 2000

This study was conducted to improve control system of insect pests, especially western flower thrips, Frankliniella occidentalis, and two-spotted spider mites, Tetreanychus urticae, of rose greenhouses. Density of thrips was relatively higher in yellow flowers than in pink or redflowers, while there was no difference in density of two-spotted spider mites by flower colors. In pest control by an automatic monorail sprayer, 89% labor and 18.2% chemical savings, as compared to the conventional high pressure spray method, were achieved without lowering the pest control effectiveness. By using an adhesive agent in combination with acaricide, adhesion of chemical to crops increased by 25% and control effect on two-spotted spider mites increased by 20.5% as compared acaricide spray alone.

• Journal of Korean Society on Water Environment
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• v.25 no.3
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• pp.432-440
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• 2009

The effect of selecting hydrologic item for calculating objective function on calibration of stream flow was evaluated by Hydrologic Simulation Porgram-Fortran (HSPF) linked with Model Independent Parameter Optimizer (PEST). Daily and monthly stream flow and flow duration were used to calculate objective function. Automated calibration focused on monthly stream was proper to analyze seasonal or yearly water budget but not proper to predict daily stream flow or percent chance flow exceeded. Calibration result focused on flow duration is proper to predict precent chance flow exceeded but not proper to analyze water budget or predict peak flow. These results indicate that hydrologic item calculated for objective function on calibration procedure could influence calibration results and watershed modeler should select carefully hydrologic item for the purpose of model application. Current, the criteria of stream flow of Korean TMDL is generated based on percent chance flow exceeded, so flow duration should be included to calculate objective function on calibration procedure for the estimation of criteria of stream flow using hydrologic model.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.607-618
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• 2012

The blueberry gall midge, Dasineura oxycoccana (Diptera: Cecidomyiidae), has known as a key pest of blueberries in the southeastern United States, Europe and Canada. It can cause considerable damage to developing flower buds and also injure vegetative growth by distorting and blackening shoot tips on blueberries. In 2010, same damage symptoms were observed on blueberries, Vaccinium spp., in Hwaseong-si, Gyeonggi-do. And, D. oxycoccana was identified from the farms and it was designated as a quarantine pest in Korea. The occurrences of D. oxycoccana and its damages were investigated in the blueberry greenhouse in 2011. Nationwide survey revealed that most of the blueberry greenhouses were infected by D. oxycoccana. An environment-friendly management method for D. oxycoccana was developed by changing soil environment in the blueberry greenhouse.