• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.194-215
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• 2021

Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.32-39
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• 2012

Efficacy of different control methods was evaluated for disease management of tomato bacterial wilt caused by $Ralstonia$ $solanacearum$. All six chemical pesticides applied to the bacterial suspension showed $in$ $vitro$ bactericidal activities against $R.$ $solanacearum$. Minimal inhibitory concentrations (MICs) of copper hydroxide (CH), copper hydroxide-oxadixyl mixture (CH+O), and copper oxychloride-dithianon mixture (CO+D) were all 200 ${\mu}g/ml$; MIC of copper oxychloride-kasugamycin (CO+K) mixture was 100 ${\mu}g/ml$; MICs of both streptomycin- validamycin (S+V) and oxine copper-polyoxine B mixture (OC+PB) were 10 ${\mu}g/ml$. Among these chemical pesticides, treatment of the detached tomato leaves with the 5 pesticides (1 mg/ml), except for OC+PB delayed early wilting symptom development caused by the bacterial inoculation ($10^6$ and $10^7$ cfu/ml). Four pesticides, CH, CH+O, CO+K and S+V, showed disease protection in pot analyses. Six plant essential oils, such as cinnamon oil, citral, clove oil, eugenol, geraniol and limonene, differentially showed their antibacterial activities $in$ $vitro$ against $R.$ $solanacearum$ demonstrated by paper disc assay. Among those, cinnamon oil and clove oil exert the most effective activity for protection from the wilt disease caused by the bacterial infection ($10^6$ cfu/ml). Treatment with cinnamon oil and clove oil also suppressed bacterial disease by a higher inoculum concentration ($10^7$ cfu/ml). Clove oil could be used for prevention of bacterial wilt disease of tomato plants without any phytotoxicity. Thus, we suggest that copper compounds, antibiotics and essential oils have potency as a controlling agent of tomato bacterial wilt.

• Journal of Biosystems Engineering
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• v.28 no.6
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• pp.511-516
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• 2003

Computer vision technology has been utilized as one of the most powerful tools to automate various agricultural operations. Though it has demonstrated successful results in various applications, the current status of technology is still for behind the human's capability typically for the unstructured and variable task environment. In this paper, a man-machine interactive hybrid decision-making system which utilized a concept of tole-operation was proposed to overcome limitations of computer image processing and cognitive capability. Tasks of greenhouse watermelon cultivation such as pruning, watering, pesticide application, and harvest require identification of target object. Identifying water-melons including position data from the field image is very difficult because of the ambiguity among stems, leaves, shades. and fruits, especially when watermelon is covered partly by leaves or stems. Watermelon identification from the cultivation field image transmitted by wireless was selected to realize the proposed concept. The system was designed such that operator(farmer), computer, and machinery share their roles utilizing their maximum merits to accomplish given tasks successfully. And the developed system was composed of the image monitoring and task control module, wireless remote image acquisition and data transmission module, and man-machine interface module. Once task was selected from the task control and monitoring module, the analog signal of the color image of the field was captured and transmitted to the host computer using R.F. module by wireless. Operator communicated with computer through touch screen interface. And then a sequence of algorithms to identify the location and size of the watermelon was performed based on the local image processing. And the system showed practical and feasible way of automation for the volatile bio-production process.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.145-152
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• 2020

The populations of Polyphagostarsonemus latus (Acari: Tarsonemidae) peaked two times on green perilla grown in greenhouses of Geumsan-Gun, Chungchungnamdo. The first peak of P. latus was in the middle of June, after it was first detected in late May. The population of P. latus peaked for the second time in mid July as its density stared rapidly increasing in early July. The application of chemical pesticides and eco-friendly agricultural materials, the two management methods used to control P. latus on green perilla, did not alter the occurrence patterns of P. latus; population size of the mite was much larger in greenhouses using chemical pesticides than in the ones using eco-friendly agricultural materials. This difference might be cuased by continuity of the management methods. Chemical control of P. latus should be limited owing to pesticide residue. The highest density of P. latus on green perilla plants was observed after 25 days after inoculation. The density was the highest in mid-aged leaves (e.g., the largest leaves) and the lowest in newly developed leaves (e.g., smallest leaves). However, there was no significant (P > 0.05) correlation between leaf size and density of P. latus. These results indicate that leaf size (e.g., leaf age) did not affect the occurrence of P. latus. Thus, any leaf of a green perilla plant is available as a sample unit for P. latus.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.251-259
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• 2007

For the development of integrated pest management system by harmonizing biological and chemical control, some experiments wee carried out to select low toxic pesticides against natural enemies. and their residual toxicity were evaluated. Leaf dipping method, body dipping method, and diet treatment method were set up for the toxicity evaluation against Cotesia glomerata adults. We had tested 46 different pesticides (31 insecticides, 11 fungicides, 4 herbicides) at recommending concentration commonly used to control diamond back moth, disease and up-land weeds in chinese cabbage field. Twenty three insecticides, eleven fungicides, and four herbicides were shown to be low toxic to C. glomerata adults in the treatment of body dipping. After insecticide spraying at recommending dose on the chinese cabbage, we examined residual effect of insecticides by introducing natural enemies on different days. Safety interval for the introduction of C. glomerata adults was established according to the residual toxicity of pesticides. Safe insecticides for the introduction of C. glomerata adults at one day after treatment (DAT) were thiacloprid, acephate, chlorfenapyr, clothianidin and at 3 DAT were imidacloprid, deltamethrin, thiamethoxam, dimethylvinphos, emamectin benzoate.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.415-423
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• 2007

For the development of integrated pest management system by harmonizing biological and chemical control, some experiments were carried out to select low toxic pesticides and to evaluate residual toxicity to natural enemies. Leaf dipping method and body dipping method were set up for evaluating toxicity to minute pirate bug, Orius strigicollis adult. We had tested 52 kinds of pesticides (33 insecticides, 19 fungicides) commonly used to control greenhouse insects, mites, and disease pests to natural enemies at the recommended concentration. Fourteen insecticides by body dipping method, 12 insecticides by leaf dipping method and 19 fungicides were selected as low toxic pesticides to O. strigicollis adult. After insecticide spraying at recommending dose on the sweet pepper plant, we examined residual effect of insecticides by introducing natural enemies on different days. Safety interval for introduction of O. strigicollis adult was established according to residual toxicity of pesticides. Safety insecticides at one day after treatment were pyraclofos, methomyl, thiodicarb, esfenvalerate bifenthrin, alpha-cypermethrin, etofenprox, fenvalerate, imidacloprid, acetamiprid, abamectin, emamectin benzoate, spinosad, indoxacarb. However, residual toxicity of nee-nicotinoids last up to 21 days to O. strigicollis adults.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.518-526
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• 2007

There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.2
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• pp.131-136
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• 2022

This study was conducted to evaluate the efficacy and phytotoxic of crop desiccant treatments on the seed production of Italian ryegrass (Lolium multiflorum Lam.) in Gimje and Buan, South Korea. Here, Italian ryegrass was treated 7, 10, and 14 days before harvest (DBH) and no difference in fresh weight, 1000-seed weight, germination rate, and seed yield was observed compared to the untreated control in the standard dose and double dose for seven DBH. However, the standard dose and double dose on the 10 DBH and 14 DBH had a lower 1000-seed weight, germination rate, and seed yield compared to the untreated control. In pesticide persistence analysis, the permitted standards were not exceeded in the seeds and straw according to the treatment time and concentration. These results suggest that the treatment effect and stability of Italian ryegrass can be expected if treated within seven DBH. However, it seems that crop desiccants should be used after considering grain ripening and weather to minimize loss of seeds.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.355-363
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• 2023

In addition to causing direct feeding damage to a variety of greenhouse crops, Frankliniella occidentalis also inflicts indirect harm by facilitating the transmission of the tomato spotted wilt virus. Historically, the prevention of F. occidentalis infestations has relied heavily on pesticide use. However, this approach has led to significant side effects in agricultural ecosystems, including the development of pest resistance and challenges in effective prevention. In response to these issues, research has been directed towards identifying alternative substances that circumvent the tolerance developed against chemical pesticides. Extracts from sixty-seven medicinal plants were prepared by soaking them in water for 24 hours at room temperature. These extracts were then applied to adult F. occidentalis, with particular attention to moutan extract treatment. This treatment demonstrated a 100% insecticidal effect on the first day. The moutan extract, specifically, was prepared using 50% ethanol, after which the ethanol and water were removed via a rotary evaporator. The resultant product was then lyophilized into a powder and used after being diluted with water. In indoor experiments, a 40% diluted solution was sprayed onto F. occidentalis, exhibiting a 100% insecticidal effect 24 hours post-treatment. Furthermore, a pot test indicated a 78% insecticidal effect on the first day of application. Ongoing research includes the analysis of active substances that demonstrate exceptional insecticidal properties and the conduct of on-site validation tests. The application of the aforementioned extract is anticipated to be effective in the prevention of F. occidentalis infestations.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.1-10
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• 2012

Fungicidal activities against phytopathogenic fungi of diarylthiazole compound of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-fluorophenyl)thiazol-5-yl]-1-methylpiperidine (I) have been determined to be excellent and compound I was used as the leading compounds in this study. Furthermore, the compound was synthesized by reacting them with five functional groups, 4-fluoro-3-methylphenyl, 4-fluoro-3-chlorophenyl, 4-chloro-2-fluorophenyl, 4-bromo-3-methylphenyl and 2,4-dichlorophenyl groups instead of 4-fluorophenyl group. Also, 2-amino-, 2-(N-ethoxycarbonyl)piperidin-4-yl-, and 2-piperidin-4-yl-thiazole were introduced as the leads instead of 2-N-methylpiperidine-4-yl-thiazol of compound I. VIII-1~VIII-5 and XIII-1~XV-5 compounds were newly synthesized and their structures were confirmed by $^1H$-NMR-spectrum. The fungicidal activities of all the synthesized compounds against Phytophthora capsici were examined using the whole plant method. Among the VIII-1~VIII-5 and XIII-1~XV-5 chemicals, XIV-3 showed the most potent antifungal activity in vivo. While the $EC_{50}$ and $EC_{90}$ values of the commercial fungicide dimethomorph and I were $4.26{\pm}0.02$, $14.72{\pm}0.05$ and $1.01{\pm}0.11$, $6.31{\pm}0.09mM$, those of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-chloro-2-fluorophenyl)thiazol-5-yl]-1-methylpiperidine (XIV-3) was $0.98{\pm}0.21$ and $5.85{\pm}0.05mM$. Therefore, XIV-3 can be considered as a viable candidate for the control of plant diseases caused by P. capsici, and further studies will be conducted on the mode of action XIV-3.