• Journal of Korean Society of Forest Science
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• v.94 no.4 s.161
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• pp.277-280
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• 2005

In order to prevent chestnuts from damage by the peach pyralid moth, Dichocrosis punctiferalis, a sprinkler system was installed on the chestnut orchard. Such a test was conducted at Yeoju-gun, Gyeonggi-do, Korea in 2002. Insecticides of fenitrothion 50% EC, x1,000 and diflubenzuron 25% Wp, x2,500 were sprayed at ten-day fifteen-day and twenty-day intervals during the period of D. punctiferalis adult occurrence by sprinkler system. The peach pyralid moths generally emerged for about 60 days from early July to early September, and peak emergence was 10 days from late July to early August. Damage rate of chestnuts were 0.9-4.0% on average with this crown insecticide spraying with diflubenzuron, while 30.4% when not treated. Control effectiveness of this insecticide spraying was 92%(86.7-97.0%). In conclusion, effectual times and number of insecticide application with sprinkle system against peach pyralid moth were from early July to late August and four or five times at ten or fifteen day intervals, respectively.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.523-528
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• 2016

The migratory locust Locusta migratoria, one of the world's most notorious insect pests, has polyphenic (gregarious or solitarious) characteristics. Although this species is known to have several morphological variants, it is genetically divided into two different lineages using mitochondrial genome analysis: Southern (Africa, Southern Europe, Southern Asia, and Australia) and Northern (East Asia and the Eurasian continent). In 2014, a large number of orange black-colored gregarious L. migratoria nymphs suddenly appeared at Haenamgun, Jeollanamdo in the south of Korea. This is the first report of gregarious phase locusts occurring in Korea. In this study, mitochondrial COI sequences of one nymph and 11 adults of L. migratoria were analyzed to examine the genetic lineage of the gregarious nymphs of L. migratoria. Our results showed that all 12 individuals belong to the Northern linage and have low intraspecific genetic divergences (0.0% - 0.9%).

• Korean journal of applied entomology
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• v.36 no.2
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• pp.156-165
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• 1997

Host plants and host preference of brown chafer, Adoretus tenuimaculatus Waterhouse (Coleoptera: Scarabaeidae) were investigated in fields and laboratory. 66 kinds of plants in 25 fanlilies were recorded as host during the field survey and 14 kinds in 5 families were verified to be eaten by artificial plant supply. Thus, host plants of A. tertuimaculatus were 186 kinds in 42 families in total including 136 kinds of plants in 32 families from literatures. 50 plants in 19 families were newly recorded as host of A. tenuimaculatus in this study. A. tenuimaculatus was the most frequently visited to J14glans sinensis and Caztanea crenata was the highest damaged plant. C. crenata, Robinia pseudoacasia, Malus sieboldii, J. sinensis, Quercus mongolica, and Q. aliena were considerably highly preferered host plant. However, A. tenuimaculatus never visited to Diospyros lotus, J. nigra, Fraxinus mandshurica, F. rhynchophylla, Pyracantha angustqolia, Paulownia coreana, and Celtis sinensis. Even the same host plant of A. tenuimaculatus. preference was different according to observed place and damage level was also different depending on observed place and time.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.457-460
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• 2023

본 연구는 시설작물의 병충해 진단을 위해 딥러닝 모델을 응용한 인공지능 서비스 앱, Dr. Vegetable을 제안하고자 한다. 농업 현장에서 숙련된 농부는 한눈에 농작물의 병충해를 판단할 수 있지만 미숙련된 농부는 병충해 피해를 발견하더라도 그 종류와 해결 방법을 찾아내기가 매우 어렵다. 또한 아무리 숙련된 농부라고 할지라도 육안검사만으로 병충해를 조기에 발견하는 것은 쉽지 않다. 한편 시설작물의 경우 병충해에 의한 연쇄피해가 발생할 우려가 있으므로 병충해의 조기 발견 및 방제가 매우 중요하다. 즉, 농부의 경험에 따른 농작물 병해충 진단은 정확성을 장담할 수 없으며 비용과 시간적인 측면에서 위험성이 높다고 할 수 있다. 본 논문에서는 YOLOv5를 활용하여 상추, 고추, 토마토 등 농작물의 병충해를 진단하는 인공지능 서비스를 제안한다. 특히 한국지능정보사회진흥원이 운영하고 있는 AI 통합 플랫폼인 AI 허브에서 제공하는 노지 작물 질병 및 해충 진단 이미지를 사용하여 딥러닝 모델을 학습하였다. 본 연구를 통해 개발된 모바일 어플리케이션을 이용하여 실제 시설농장에서 병충해 진단 서비스를 적용한 결과 약 86%의 정확도, F1 Score 0.84, 그리고 0.98의 mAP 값을 얻을 수 있었다. 본 연구에서 개발한 병충해 진단 딥러닝 모델을 다양한 조도에서 강인하게 동작하도록 개선한다면 농업 현장에서 널리 활용될 수 있을 것으로 기대한다.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.189-194
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• 2004

This study investigated the species of leafrollers in apple orchards and nursery farms in Gyeongsangbuk-do for three years from 1998 to 2000, and also examined the occurrence and damage of leafrollers in commercial apple orchards in 5-6 cities and districts for 10 years from 1992 to 2001. Total seven species of tortricidae were found in the apple orchards, which were Adoxophyes orana, Archips breviplicanus, Rhopobota unipunctana, Choristoneura longicellana, Acleris fimbriana, Ptycholoma lecheana circumclusna and Archips subrufanus. Among them, A. orana was dominant species every year, and A. breviplicanus and R. unipunctana occurred with a high density in one or two farms in some years. The dominant species in the 1980s were A. breviplicanus and R. unipunctana, but it was considered that dominant species have been changed in the late 1990s. According to the result of leafroller damage in commercial apple orchards for 10 years, the mean fruit damage rate was $0.67\%$. Fruit damage was observed frequently between August and October by third-generation larvae.

• 보존과학연구
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• s.33
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• pp.99-108
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• 2012

The white-rot fungus (Trametes versicolor) and brown-rot fungus (Tyromyces palustris), which cause damage to a variety of wooden cultural properties and buildings, such as drying of the wood tissue, decay and cracks, sponge, and discoloration, give rise to serious structural and aesthetic problems. Moreover, pest termites (Reticulitermes speratus kyushuensis Morimoto) can cause damages like hollowing the outdoor beams or pillars of wooden buildings and finally causing such buildings to collapse due to the termites' destruction of the inside of the beams or pillars, leaving only a thin layer on their surfaces. This study was conducted to determine the impact of the wood-decay fungus, a representative damage-causing microorganism, and of insects and termites on the termite ecology. The damage ratio was calculated as the weight of the timber, and the overall total mass was reduced from two kinds of rot fungi. The white-rot fungi reduced the total wood mass, but the brown-rot fungi were observed to have had an increasing tendency to do so. The wood mass was measured after drying to determine the destruction capacity of termites. As a result, the wood mass consumed by the brown-rot fungi was shown to be greater.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.301-307
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• 2001

The pine needle gall midge (PNGM), Thecodiplosis japonensis Uchida et Inouye, is a serious pest in pine forests in Korea. Since the first report of PNGM infestation in Korea in 1929, the infestation area has been expanded gradually. In 1975 the distribution of PNGM and its parasitoids were surveyed throughout several infested areas in Korea. Annual survey has been made for the rates of gall formation by PNGM and parasitism by its parasitoids at the monitoring sites including newly infested area in 1975 since 1980. These data were used to examine the relationship between PNGM and its parasitoids for newly invaded areas. The gall forming rate of PNGM and the parasitism by the parasitoid were 34.8 and 1.9% in 1975, respectively, while the gall forming rate and the parasitism were 20.7 and 8.9% in 1985, respectively. The relationships of densities between PNGM and its parsitoid were weak in the early stage of dispersion, but the density of parasitoid was with an asymptotic increase along with PNGMs density increase during the observation period for 10 years.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.89-97
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• 2000

Insect pests of eggplant, pepper, Chinese cabbage, watermelon, cucumber, melon, and tomato seedlings were surveyed in eleven propagation houses from 1998 to 1999. Ten species of insect pests of nine genera in eight families, two species of mites of one genus in one family, and three species of slugsor snails in three genera belonging to two families were found from the observed seedlings but Bradysia agrestis was the most serious pest out of them. Thus, occurrence and damage of B. agrestis were investigated in two propagation houses all the year round. In the observation of seedling mortalities of seven crops in May, July, October and the following February, only watermelon seedlings were withered and dead by the larva of B. agrestis with different mortality depending on time representing 81.9%, 41.3%, 54.9%, and 79.1%, respectively. All the developmental stages of B. agrestis were found every month throughout the year. Larval density and adult density were different according to season with the highest numbers in May showing 34.9 and 407.4, respectively. Mortality of watermelon seedlings was higher in April and May than the other months showing 83.3% in April and 82.4% in May. The number of adults attracted to sticky trap was also different depending on card colour. The number of adults was much higher on yellow sticky card (326.2) than blue sticky card (20.2). In the investigation of the number of adults on yellow sticky card at 25 cm and 120 cm above the bench and 10 cm under the bench, more numbers of adults were caught at 25 cm above the bench (273.7) and 10 cm under the bench (320.1) than 120 cm above the bench (27.9). Mortalities of cucumber, pepper, and watermelon seedlings after transplanting in greenhouses were not significantly different depending on culture method.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.85-90
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• 1998

A series of experiments were carried out to determine the effect of seed dressing application of chemicals on the early occurring rice insect pests. The number of small brown planthopper adults per 3hills in seed-dressing plot of Imidacloprid WS (Im WS) was 1.6 and its control efficacy was over 90%, compared with that of untreated plot. Rice water weevil was observed in the density of 8.8 larvae per 5 hills seed-dressed Im WS plots(showing 95.5% of control efficacy). Control efficacy of Im WS and Im GR against adult weevils lasted for 26 days after treatment and was higher than that of Carbofuran GR. Rates of injured stems by rice stem maggot and injured leaves by rice leaf miner were 3% and 3.7% in Im WS treatment plot respectively. Seed germination rate after seed dressing with recommended dosage (3 g/seed kg) of Im WS was 71 % on the 1st day and increased on 5th day up to that of untreated seed. The residual amount of Im in seed dressing plot was 0.11 ppm in rice roots and 0.05 ppm in leaves on the 40th day after treatment. Residual effect of Im WSI sustained for 50 days with over 95% insecticidal effect for the rice water weevil and over 90% for the brown planthopper. Quantity of the chemical applied in the field was calculated as 0.084 kg a.i./ha in seed dressing and 0.3 kg a.i./ha in seed box treatment, respectively It took 1 hour to treat insecticide by seed dressing, 2.5 hours by seed box applying, and 3.6 hours by water surface releasing per 990 $m^2$.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.409-425
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• 2018

Occurrence and yield characteristics of lepidopteran insect pests in both PUR (paddy-upland rotation) and CU (continuing upland) fields for 8 maize (Eolrukchal 1, Heugjeom 2, Miheukchal, Ilmichal, Heukjinjuchal, Chalok 4, Mibaek 2, Daehakchal) and 7 sorghum (Hwanggeumchal, Anzunbaengisusu, Moktaksusu, Sodamchal, DS-202, Nampungchal, Donganme) varieties was surveyed. The population of Ostrinia furnacalis adults showed 3 times highest peaks in 2016. In addition, the damaged ratios of maize and sorghum leaves and stems were increased depending on the growth periods of the crops and those by O. furnacalis larvae were also increased steeply in mid August. The damaged ratios of maizes such as Miheukchal, Eolrukchal 1, Ilmichal, Heugjeom 2, and Mibaek 2 by O. furnacalis larvae were statistically different (P=0.05) between organically managed PUR and CU fields. Except for DS202 among sorghum varieties, the damaged ratios of the other ones were high and similar (50-92%) in the CU field. The ear damaged ratio of maize varieties by lepidopteran larvae including O. furnacalis and Helicoverpa armigera was from 5 to 38% in Chalok 4 and Heukjinjuchal, respectively, and Daehakchal gave relatively higher damage ratio in the PUR field (33%) than in the CU field (14%). The ear ratio of Sodamchal and DS-202 varieties in the PUR field was 94 and 82%, and all sorghum varieties were damaged over 78% by lepidopteran larvae in the CU field. Interestingly, the correlation coefficients between the damaged ratio and invasive pores on their stems by O. furnacalis larvae were positive (maize $r=0.69_{paddy-upland}$, $0.95_{continuing}$; sorghum $r=0.93_{paddy-upland}$, $0.97_{continuing}$, respectively). Additionally, the correlation coefficients between the damaged ratio and the ear weight or the thousand kernel weight (g) of maizes and sorghums by lepidopteran larvae were negative (maize $r=-0.38_{paddy-upland}$, $-0.49_{continuing}$; sorghum $r=-0.70_{paddy-upland}$, $-0.57_{continuing}$, respectively). These results indicate that the focused management on lepidopteran insect pests occurring maizes and sorghums cultivated in PUR and CU fields is an important strategy to secure their yields.