• Korean journal of applied entomology
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• v.34 no.1
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• pp.9-14
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• 1995

From a chemist's perspective, Scarabaeidae is one of the most exciting group of insects to work on the isolation, identification, and synthesis of sex pheromones because-as opposed to Lepidoptera, which by and large utilizes straight chain alcohols, aldehydes, and acetates-the pheromonal chemistry of scarab beetles is remarkably diverse. While species in the subfamily Rutelinae utilize pheromone constituents, which are presumably fatty acid derivatives, the more primitive species in the subfamily Melolonthinae use phenolic, amino acid derivative, and terpenoid compounds. Here, I discuss the recent advances we have accomplished in the identification of scarab sex pheromones with especial emphasis on their chemical diversity. Also, I discuss the potential role of these sex pheromones in insect pest management. Field tests revealed that, in contrast to what has been frequently observed in the Lepidoptera, the higher the dosage of sex pheromone loaded in the traps the greater the capture of scarab beetles. These data suggest that mass trapping is more likely to be useful for scarab pest management than mating distruption.

• Journal of Species Research
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• v.8 no.2
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• pp.233-237
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• 2019

Mites in the family Veigaiidae, order Mesostigmata, subclass Acari are widely distributed in subsoil habitats. They are mostly free-living and predaceous on small arthropod eggs and larvae, and prefer habitats with rich organic matters including litter and humus layers of forest soil. The genus Veigaia Oudemans, 1905 of the family Veigaiidae (Acari: Mesostigmata) is one of the ubiquitous genera from the Holarctic Region. Until now, only two genera and five species of the family were recorded from Korea. Here we provide a report of the species Veigaia tibbetsi Farrier, 1957 with detailed redescription. Even though V. tibbetsi had appeared in some ecological literature, this is the first record of this species in Republic of Korea. This species was mostly found from pine forest(Pinus densiflora) of northeastern mountainous parts of the Korean Peninsula, in Gangwon and Gyeongbuk Provinces. We provided some ecological characteristics of the family Veigaiidae, which will help to further exploration of acarine biodiversity.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.328-333
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• 1998

To obtain basic information for establishing a pest control strategy for insect pest management system, changes in the population densities of the black-tipped sawfly(Acantholyda posticalis posticalis Matsumura) and damage patterns in tree growth were investigated in national forests in Hoigok-ri, Kapyung-gun, Kyunggi-do, where the pest control measures were taken. The results obtained were as follows ; 1. The larval density in the soil of the forests where the insecticides were applied have been kept below economic threshold for about 7 years. The density was the highest in the middle of slopes and similar to the level of the early stage of the insect outbreak. 2. After the pest control by insecticides, reduction in tree height and diameter growth lasted for 2-3 years in trees defoliated by over 70%. 3. The diameter growth of the trees damaged by black-tipped sawfly recovered faster in upper stem than in the lower. 4. volume growth of the trees defoliated over 70% by the insect decreased for three to four years. The volume loss of trees defoliated by 70% and 90% was 19.6% and 54.0%, respectively. 5. Maintaining the rate of defoliation below 50%, which is the economic threshold, by chemical control measures had an effect of reducing the tree volume loss by $40m^2/ha$ as compared with a stand defoliated by 90%.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.3
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• pp.107-113
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• 2003

Ecological control can contribute to the sustainibility of vegetation management systems by reducing the input currently derived from non-renewable fossil energy sources. The use of turfgrass mixtures is an important tool in turf management. Turfgrass mixtures of two or more compatible and adapted species provide improved tolerance to pest and environmental stress, more so than monostands. The objectives of this study were to evaluated turf insects, pests and zoysia large patch control by turgrass mixtures. In April 2001 and 2002, plots were inoculated with 50g of Rhizoctonia solani AG2-2LP inoculum. Inoculum were treated within a 29cm diamater circle at Zoysia japonica, Zoysia japonica, Poa pratenis, or Festuca arundinacea mixtures. After four weeks, disease severity in each plot was determined. plot area visual ratings were assessed visually on a linera 0 to 100%. In August 2001 and October 2002, turf insects and pests in each plot were investigated in 10cm deep soil cores with 8cm diameters using hole cut. Zoysia large patch affected zoysiagrass monostands more severly than zoysiagrass and cool-season turfgrasses mixtures. It was suggested that the barrier effect of cool-season turfgrass suppressed zoysia large patch in the mixture of zoysiagrass and cool-season turfgrasses. Also, warm-season and cool-season turfgrasses mixtures suppressed insect populations more efficiently than warm-season turfgrass monostands.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.67-76
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• 2014

The objective of this study is to estimate the economic value of official management and control for invasive insects and diseases in fruits. The direct and indirect effect of this control measure can be the changes in price of fruits and related goods, changes in export volume of domestic fruits, changes in total volume of fruit production, and reduce the risk in food safety. The contingent valuation method with the single-bounded dichotomous choice is employed to estimate each household's willingness-to-pay (WTP) to maintain official management and control measures. The total number of sample consists 2,050 respondents between the ages of 19-60 years, and the survey is conducted using Web-based survey. The estimated results for mean WTP is 5,443won per month per household. Therefore, the total economic value of official management and control on fruit in Korea is estimated to be approximately 94.4 billion won per month.

• Korean journal of applied entomology
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• v.31 no.3
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• pp.205-240
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• 1992

In reality, it is a green revolution of the entire agricultural matrix in Korea that integrated pest control plays an important role in the possible breakthrough in rice self-sufficiency. In paddy agroecosystem as man-modified environment, rice is newly established every year by transplantation under diverse water regimes which affect a microclimate. Standing water benefits rice by regulating the microclimate, but it favors the multiplication of certain pets through the amelioration of the microclimate. Further, the introduction of high yielding varieties with the changing of cultural practices results in changing occurrence pattern of certain pests. In general, japonica type varieties lack genes resistant to most of the important pests and insect-borne virus diseases, whereas indica type possesses more genes conferring varietal resistance. Thus, this differences among indica type, form the background of different approaches to pest management. The changes in rice cultivation such as double cropping, growing high-yielding varieties requiring heavy fertilization, earlier transplanting, intensvie-spacing transplanting, and intensive pesticide use as a consequence of the adoption of improves rice production technology, have intensified the pest problems rather than reduced them. The cultivation of resistant varieties are highly effective to the pest, their long term stability is threathened because of the development of new biotypes which can detroy these varieties. So far, three biotypes of N. lugens are reported in Korea. Since each resistant variety is expected to maintain several years the sequential release of another new variety with a different gene at intervals is practised as a gene rotation program. Another approach, breeding multilines that have more than two genes for resistance in a variety are successfully demonstrated. The average annual rice losses during the last 15 years of 1977-’91 are 9.3% due to insect pests without chemical control undertaken, wehreas there is a average 2.4% despite farmers’insecticide application at the same period. In other words, the average annual losses are prvented by 6.9% when chemical control is properly employed. However, the continuous use of a same group of insecticides is followed by the development of pest resistance. Resistant development of C. suppressalis, L. striatellus and N. cincticeps is observed to organophosphorous insecticides by the mid-1960s, and to carbamates by the early 1970s in various parts of the country. Thus, it is apparent that a scheduled chemical control for rice production systems becomes uneconomical and that a reduction in energy input without impairing the rice yield, is necessarily improved through the implementation of integrated pest management systems. Nationwide pest forecasting system conducted by the government organization is a unique network of investigation for purpose of making pest control timely in terms of economic thresholds. A wise plant protection is expected to establish pest management systems in appropriate integration of resistant varieties, biological agents, cultural practices and other measures in harmony with minimizing use of chemical applications as a last weapon relying on economic thresholds.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.197-210
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• 2022

Entomopathogenic fungi can be used to control a variety of sucking and chewing insects, with little effect on beneficial insects and natural enemies. Approximately 170 entomopathogenic fungal insecticides have been registered and used worldwide, with the recent focus being on the mode of action and mechanism of insect-fungal interactions. During the initial period of research and development, the industrialization of entomopathogenic fungi focused on the selection of strains with high virulence. However, improvement in productivity, including securing resistance to environmental stressors, is a major issue that needs to be solved. Although conidia are the primary application propagules, efforts are being made to overcome the limitations of blastospores to improve the economic feasibility of the production procedure. Fungal transformation is also being conducted to enhance insecticidal activity, and molecular biology is being used to investigate functions of various genes. In the fungi-based pest management market, global companies are setting up cooperative platforms with specialized biological companies in the form of M&As or partnerships with the aim of implementing a tank-mix strategy by combining chemical pesticides and entomopathogenic fungi. In this regard, understanding insect ecology in the field helps in providing more effective fungal applications in pest management, which can be used complementary to chemicals. In the future, when fungal applications are combined with digital farming technology, above-ground applications to control leaf-dwelling pests will be more effective. Therefore, for practical industrialization, it is necessary to secure clear research data on intellectual property rights.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.86-95
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• 2003

The object of this paper is to correct check the tree situation and quantity around highway. Also, those data utilize in order to establish plan about how to the long and short term landscape construction and maintain program. The result of this study can be summarized as follows; 1. Tree decrease rates for 8 branch offices were Jongbu(5.62%), Gangwon(4.32%), Chungcheong (3.35%), Honam(5.62%), Gyeongbuk(3.06%), Gyeongnam(5.60%), Seorak training center(0.31%), Headquarter(1.54%). Also decrease causes were traffic accidents(1.8%), air po11ution(4.7%), humid damage(0.9%), insect and disease(1.2%), wind and rainfall(3.4%), dry damage(3.5%), cold damage (1.0%), fire(3.1%), damage of the man and anima1(4.1%), remove bad tree(13.1%), bad rooting(9.5%) and etc.(53.7%). 2. Improve methods of tree death problems were regulation management(ferti1ize, irrigation and pesticide work), improvement of draining system, Pull out the weeds, Plant native plants, utilize organic matter fertilize and plant environment trees.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.27-37
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• 2000

This study aims at restoring urban forest destructed and eliminated by industrialization, urbanization, and city development and presenting a direction to manage remaining urban forest ecologically. To this end, an experiment zone where Populus tomentiglandulosa T. Lee were selective cutted and a control zone where Populus tomentiglandulosa T. Lee were kept intact were created in Chongdam Park located in Kangnam-ku, Seoul. Then, the structural changes of herbaceous plant species, the growth of targeted woody plants, and the increase of the number of insect and bird species were examined. The conclusions reached in this study are as follows. First, for the sake of ecological restoration and management of urban forest, it is good to selective cutting. Although timing, frequency, and methods may vary depending on the features and types of urban forest, the study revealed that selective cutting contributes to the restoration speed of origin vegetation and the enhancement of biodiversity including plants and insects. Second, as for the correlations of selective cutting and the appearance of plant species, the growth of origin vegetation, and insect distribution, the study showed that the impact of meteorological environment such as brightness is much greater than that of soil environment. Third, in order to manage urban forest, tramping pressure needs to be controlled efficiently. The efficient control of tramping pressure would contribute in the appearance of herbaceous plants. It would also be beneficial in promoting biodiversity of birds by removing the impact of people using routes. Fourth, in order to enhance the overall biodiversity of urban forest, diverse environment needs to be provided. In particular, it is necessary to supply water that is insufficient in urban forest. Providing habitats such as forest wetland performs an important function to amphibians and birds that require water as well as the appearance of aquatic plants and insects. Therefore, ways to introduce water efficiently should be initiated.

• Research in Plant Disease
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• v.25 no.4
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• pp.173-178
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• 2019

From our field investigation from 2017 to 2018, five diseases and four insect pests have been identified as the primary biotic stressors of fruit-producing mulberry, which include popcorn disease and mulberry sucker, respectively. In this study, we examined the relative control effects of selected agro-chemicals against the popcorn disease and mulberry sucker. Our systemic treatment methods to simultaneously control the popcorn disease and the mulberry sucker indicated that an integrated control method showed a superior result with the control efficacy of 89.3%, while a conventional control method resulted in 66.7%. As a result, we concluded that it is much efficient to control both disease and insect pest in mid-April while sequentially applying chemicals only for the popcorn disease from February. By considering the ecological aspects of the popcorn disease and mulberry sucker, this systemic treatment will be able to reduce the labor of growers required for the control.