• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.3
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• pp.94-100
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• 2008

New type of the sewer drainage has been developed to overcome present sewer drainage's shortcoming. This system has the function of drainage, sewerage, reverse flow prevention, and harmful insect and smell prevention. Numerical simulation has been carried out in order to minimize the troubles that can be happened in the process of manufacture and installation process. This sewer drainage system for harmful insect and smell prevention intercepts pollution source, and then it prohibit second pollution. Harmful insect cannot go in and out in this system. Also, this system can reduce the damage of flooded districts due to heavy rain because it is impossible to flow backward from sewer drainage.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.237-241
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• 1994

Surveys were conducted in 66 ginseng fields damaged by insect and other an~mal pests from 1984 to 1993. Holohichio rnoroso, Holotrichio dromphalio, Holotrichia titonis Malodera orientaliq Ectinus sericeus, Gyllotalpa ofricana, Teleog~iluse mmo, Ostrinio furnacoii* Agrotis tokionis, Marnestro brassicae, Hydrellia griseolo, unidentified stem maggo$, Pseudococcus comstocki (13 species of insects). Deroceras uarions (slug), Acusta despecta sieboldiona (snail), probably two species of rats. and pheasant species were ascertained to damage ginseng plants M them, Holotrich~a morosa, Holotrichia diomphalia, Gryliotaipo africanq Deroceras uarions, Acusto despech siebaldiano showed higher frequencies. Underground (root) damage occul~ed mainly in spring penod (MayJune) and fall period (September-Odober) in 2-year-old glnseng fields at slopes, and aboveground (leaf and stem) damage occurred mainly in spring period in 3 or more-year-old ginseng iields mulched with rice straws at plains. Three ginseng fields were abolished due to heavy underground damage.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.174-181
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• 1992

Early, mid, and late maturing soybean varieties were artificially infested with larvae of Delia platura at seeding, and then later development and productivity of soybeans were studied. In addition, in hope to utilize as possible tactics in the management of D. platura in soybeans, cultural factors such as contents of organic matter in soil, soil types, and the use of plastic mulching on the degree of damage to soybean plants by D. platura were examined. Primary leaf damage by the larva delayed the forthcoming vegetative growth but not the blooming which is initiated by the change in day length. Degree of delay in growth was more severe where leaf damage was induced by insect infestation than where artificially excised, apparently owing to simultaneous damage in stems and roots besides primary leaves. Productivity of soybeans also dropped significantly in plants with 25 % or more loss in the primary leaf area by the larva. Both transparent and black plastic mulchings shortened the period from seeding to emergence of soybean thus reducing the chance of possible attack by the larva. Soybean seedlings grown in clay loam or clay were attacked less by the larva than those in other types of soil. High organic matter content in the soil enhanced speed of emergence resulting in less larval damage to the seedling.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.127-131
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• 2008

Ambrosia beetle, Platypus koryoensis, is a vector of oak wilt disease caused by Raffaelea sp. in Korea. The degree of damage by oak wilt disease was dependent on the density of the beetles in the oak trunk, a relationship between the degree of damage by oak wilt disease and the density of beetle on the basis of the number of entry hole was studied. Entry hole distribution within tree trunk was analyzed by the nearest neighbor method. Thirty four oak trees (Quercus mongolica) located in survey area were selected and then degree of damage, the number of attack hole/$623cm^2$ in upper (50cm from the surface) and lower (surface) trunk and the nearest neighbor distance between the holes were measured. The number of hole and the nearest neighbor distance in upper and lower part were positively correlated with each other. As the degree of damage was severer, the number of the holes increased, whereas the nearest neighbor distance decreased. The distribution pattern of the hole was changed from clumped one to uniform as the severity of damage increased. These results suggested that Platypus koryoensis attacked the oak tree in concentrative manner at initial stage of attack but at final stage, it distributed uniformly to reduce intraspecific competition between the beetles.

• The Korean Journal of Zoology
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• v.13 no.1
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• pp.3-8
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• 1970

1. Paju area of Kyonggydo has received serious damages by Dryocosmus kuriphilus Yasumatsu in the bushes of Castanea crenata S. et Z. since 1965. I have also found the middle parts of whole country of Korea has damaged by this wasp. 2. Bobwonri was the worst case in its damage by Dryocosmus kuriphilus Yasumatsu with most prosperous parasite, Aletia flavostigma singularis Butler and Dictyoploca japonica Moore. I conclude that this is the result of the lack of beneficial insects and isolated bush formation. 3. The chestnut bush at Bunsuri was recovering from the damage of gall wasp nevertheless it was illustrated big damage at last year's hranches. I conclude that this recovering phenomena is closely related with the insect fauna of this area and this characteristic insect fauna was derived from the bush formation which reveals specific bush arrangement that can be illustrated as surrounded by another bush of Quercus acutissima Carruthers. 4. As a final conclusion, I recommend mixed bush formation of chestnut tree with Quercus species to control insect population dynamics in healthy status.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.70-74
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• 2015

The current market size of insect industry in Korea is estimated at 300 million dollars and more than 500 local farms are related to many insect industry. One of the strong candidates for insect industry is Korean horn beetle, Allomyrina dichotoma. Early this year, we reported a viral disease extremely fatal to A. dichotoma larvae. While we were proceeding a nationwide investigation of this disease, it was informed that similar disease symptom has been occurred occasionally during past over 10 years. The symptom can be easily confused with early stage of bacterial infection or physiological damage such as low temperature and high humidity. A peroral infection with the purified virus to healthy larvae produced a result that only 21% of larvae survived and became pupae. Although some of the survived adult beetle was deformational, many of them had no abnormal appearance and even succeeded in mating. Later, these beetles were examined if they were carrying the virus, and all except one were confirmed as live virus carrier. This implies that these beetles may fly out and spread the disease to the nature. We found the evidence for this possibility by collecting a few wild A. dichotoma larvae which were virus infected, near two local farms rearing A. dichotoma larvae. So far, transovarial transmission of this virus to the eggs, or horizontal transmission to other commercially reared insects is not known yet.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.267-274
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• 2000

As the pest of the citrus in Cheju, 69 insect species and 5 animal species were investigated during 1996 to 1998. Of these, Panonychus citri, Phyllocnistis citrella, Aphis citricola, Aphis gossypii and Frankliniella occidentalis are major pests. Especially, F. occidentalis and Peridroma saucia are very important species because of increasing damage. The number of pests species injuring leaf, branch, fruit and flower of the citrus are 36, 16, 41 and 2 species respectively. The rate of damaged fruits by pests is 20.5% in 1997 and 18.6% in 1998 and the rate of bad quality fruits is 6.4% and 6.7% respectively.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.45-51
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• 2016

Thirty-seven species of insect pests were surveyed on different area blueberry farms in Jeonbuk province during 2013~2014. Six principal insect pests were found, including Dasineura oxycoccana Johnson, Aphis gossypii Glover, Scirtothrips dorsalis Hood, Ricania sp., Hyphantria cunea Drury, and Latoia consocia Walker. A. gossypii infestation was severe at Iksan and Jinan in middle May. S. dorsalis infestation was severe at all surveyed area in early June, which is the flowering season, and the degree of damage caused was higher in young plants. Ricania sp. was abundant in Jinan and Sunchang, and then appeared to spread across all areas in Jeonbuk. H. cunea had a tendency to concentrate in Iksan during June. Five species of Limacodidae was found, including L. consocia, which was dominant in all areas surveyed, with densities higher then those of the others four species. The degree of damage due to D. oxycoccana was higher in the plain areas (Iksan) than in the middle-mountain areas (Jinan, Sunchang). The rate of damage was 60~78% higher in young plant stages (i.e., those under 3 years of tree age) than in those over 5 years old (30~50%). Moreover, the rate of damage observed in greenhouses was 50~80% higher than that observed in the field (30~40%).

• Journal of the Korean Wood Science and Technology
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• v.31 no.2
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• pp.69-76
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• 2003

Front columns of buildings were most severely damaged by insects. Hole diameter damaged by insects were different in each location on columns, that is, bottom, middle position, or top of columns. That mean various insects attacked on columns of wooden traditional buildings because kinds of each insect depends on the hole diameter. Specially, middle position of columns were harmed seriously. Hole diameters damaged by insects were various from 1 mm to 10 mm, but approximately 5 mm diameter was found most commonly.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.215-219
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• 1975

The number of instars of pear sawfly larvae (Janus piri Okamoto) collected front field pear trees, were determined by measuring the width of head capsule, and the growth ratio in each instar was also studied. 1. The larval head width had six distinct peaks, which suggests that the larva of this insect passes six instars. 2. The head width tended to increase as the instars avdance, except in tile first and second instars. The coeffieient of variation decressed as the instars advanced. The growth ratio, which was similarly great in the first and second instars, decreased as the instars advanced. 3. Gains' and Campbell's formulae seemed to be more suitable than Dyer's for the determination of larval instars of this insect by the measurement of headwidth. 4. The larval instars could be inferred from the extent of damage to pear tree by this insect; that is the larvae in the second to fourth instars usually gave slight and invissible damage, while those in the fifth to sixth instars gave rapid and severe damage.