• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.49-58
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• 2012

Greenhouse whitefly, $Trialeurodes$ $Vaporariorum$, is the most important insect pest in environmental friendly tomato production. Natural enemies, $Nesidiocoris$ $tenuis$ and environmental friendly agricultural materials (EFAM) are major control agents in Korea. The aim of the present work is to evaluate release time of $N.$ $tenuis$ in controlling of $T.$ $vaporariorum$ and to select environmental friendly agricultural materials (EFAM) to suppress both $T.$ $vaporariorum$ and $N.$ $tenuis$ which if the density were high causing necrotic rings. Six EFAM selected to control of $Trialeurodes$ $Vaporariorum$ in three times spray with seven days intervals. Three EFAM showed high mortality 67.7-70.5% in spray after release plot but low in release after spray plot. It should be careful to spray with $N.$ $tenuis$. When $N.$ $tenuis$ were early release at 7 days after transplanting which before occurring and establishment of greenhouse whitefly, it could suppress the density. Extracts of bead tree + matrin, matrin 1, Chrysanthemum showed high mortality on $T.$ $vaporariorum$ adults and $N.$ $tenuis$. The results suggested that this three EFAM could be control agents of the damage of necrotic rings from $N.$ $tenuis$.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.295-301
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• 2015

We investigated mycophagous ladybird, Illeis koebelei from 12 species of plants infected with powdery mildew in Gyeonggi-do, Korea. The pear tree, Pyrus ussuriensis var. macrostipes (Nakai), was most preferred by I. koebelei. This species was found from early July to early November in pear orchards. There was no entomophagous trace in the gut of I. koebelei without powdery mildew spores in a microscope. All stages except egg and pupa are obligate mycophagous, and the feeding potential is ranked as follows: fourth instar, adults, third instar, second instar, and first instar. Feeding amounts of each stage of I. koebelei were 45.6, 144.4, 372.2, 628.1, and $473.7mm^2$ of cucumber powdery mildew per day. Fourth instar larvae showed highest consumption of cucumber powdery mildew. Developmental periods of four larval instars and adults feeding cucumber powdery mildew were 1.2, 2.3, 2.3, 4.6, and 37.7 days, respectively, at $25^{\circ}C$. In this study, we could not determine the feeding potential of I. koebelei against the cucumber powdery mildew; therefore, and further studies are required to elucidate the potential of this species as a biological control agent, e.g., mass rearing, selection of low toxic chemical agents for Integrated Pest Management (IPM), and control techniques against powdery mildew in agro-ecosystems.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.707-717
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• 2018

The acaricidal activity of extracts of Gleditsia japonica var. koraiensis, Camellia sinensis, Cinnamomum cassia, Lantana camara and their mixtures against the tea red spider mite, Tetranychus kanzawai was evaluated. Treatments with mixtures 3 and 1 were effective against the adult females of T. kanzawai and yielded 82.0% and 77.3% adulticidal activities at 7 days after treatment, respectively. Treatment with mixture 2 revealed 68.0% adulticidal activity. Generally, the acaricidal activity of the single treatment of each plant extract was lower than the mixtures. The adult females of T. kanzawai treated with mixtures 3 and 1 produced only 24.0~29.6% as many eggs as control females did. The residue of the plant extracts tested had low adulticidal activity (16.7~31.3% at 7 days after treatment). All the plant extracts tested exhibited no remarkable toxic effect to the eggs of T. kanzawai. Treatments of mixtures 3 and 1 were effective against nymphs of T. kanzawai and led to emergence rates of 16.7 and 22.0%, respectively. These results suggest that mixtures 3 and 1 might be used for the control of T. kanzawai in tea fields.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.299-305
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• 2023

Bemisia tabaci is one of polyphagous insect pests that transmits Tomato Yellow Leaf Curl Virus (TYLCV) and Cassava Brown Streak Disease (CBSD). Insecticides are primarily applied to control B. tabaci, but it has limits due to the development of resistance. As a result, a fixed precision sampling plan was developed for its integrated pest management (IPM). The tomato plants were divided into top (more than 130cm from the ground), middle (70 cm to 100 cm above the ground), and bottom (50 cm or less above the ground) strata, before visual sampling of the larvae of B. tabaci. The spatial distribution analysis was conducted using Taylor's power law coefficients with pooled data of top, middle, bottom strata. Fixed precision sampling plan and control decision-making were developed with precision levels and action threshold recommended from published scientific papers. To assess the validation of the developed sampling plans, independent data not used in the analysis were evaluated using the Resampling Validation for Sampling Plan (RVSP) program.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.53-61
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• 2024

The susceptibility of Aphis gossypii populations collected from three fields (WJ, CC, and GS) was evaluated to three insecticides (afidopyropen, chlorfenapyr and cyantraniliprole) and three binary mixtures. Three field populations showed resistance ratios of over 100 to all insecticides. The Combination Index (CI), %M_(synergism), Co-Toxicity Coefficient (CTC), Wadley Ratio (WR), Synergism Ratio (SR) and Abbott Ratio (AR) were used to evaluate combined effect of the insecticides. Afidopyropen + chlorfenapyr (CI ≤ 0.16; %M_(synergism) ≥ 94; CTC ≥ 764.5; WR ≥ 6.4; SR ≥ 6.9 and AR ≥ 1.1) showed a synergism in all filed populations. WJ and CC populations showed a synergism in all binary mixtures of insecticides, but GS population showed an antagonism for chlorfenapyr + cyantraniliprole (CI, 1.63; %M_(synergism), 30; CTC, 64.0; WR, 0.6 and AR, 0.54) and afidopyropen + cyantraniliprole (CI, 6.7; %M_(synergism), 1; CTC, 19.8; WR, 0.2 and AR ≤ 0.55). All mixtures (afidopyropen + chlorfenapyr, chlorfenapyr + cyantraniliprole and afidopyropen + cyantraniliprole) showed a control value of over 99% after 21 days of treatment in the field. This study highlights that binary mixtures of three insecticides serve as an effective control strategy for A. gossypii.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.535-542
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• 2012

This study was carried out from 2011 to 2012 in order to analyze the cultivation technology system by six organic rice cultivation types in the southern provinces for the purpose of utilizing organic rice farming guidelines. This surveys were conducted by site visit on 8 counties and 115 farms in southern area. Cultivation technology system by six organic rice cultivation types were cultivated by the principle of minimum input or non-input. cropping systems, a mixture of barley and rice, or rice green manure crops were grown. Cultivars were mixture of the local cultivars and Japanese varieties. Soil were managed by a self-manufactured compost, indigenous microorganisms and barley straw without any fertilization. Pest control was mainly practied by purchased eco-friendly organic materials or herbal medication residue and indigenous microbial self-manufactured. Weed was controled by snails and barley straw. In addition, considering the restore of a longtail pitching shrimp and grasshoppers, the fuction of environmental ecology of six organic rice cultivation type proved to be excellent all. Meanwhile, the productivity of the organic farming per 10a were the order of Life and environment > Natural circulation > Stevia > Ji jang > Art and nature > Taepyoung of Farming Methods, but the farmers received prices showed the opposite tendency. Simple profitablity did not show a big difference. But, the productivity of all type of the organic farming were lower then the conventional farming. Finally, If we want to conduct safety and easy farming, we can suggest stevia farming, Natural circulation farming and life and environmental farming out of 6 organic rice cultivation types.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.272-280
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• 2013

This study aims to develop a standard diagnostic table for management and administration that oak mushroom cultivators of forestry households can utilize. By diagnosing their current level of management with the table, the cultivators themselves will be able to grasp and address their operational challenges better. The table is composed of; questions on the status of forestry households; columns for a series of management performance indices, and; questionnaire with 4 categories and 20 subcategories to check the current level of management and administration by the households. In order to prepare the standard diagnostic table for oak mushroom management, 196 forestry households throughout 10 areas - Cheong-yang, Gong-ju, Bu-yeo and Seocheon in Chungcheongnam-do, Mun-kyung and Ye-cheon in Gyeongsangbuk-do, Jin-an in Jeollabuk-do, Jangheung and Jang-seong in Jeollanam-do, and Jeju Islands - were interviewed with and a total of 190 questionnaires were acquired and made use of in the result analysis. Then, the score on management level of each forestry household was determined in the way of aggregating scores from each subcategory. The overall average score of every household was calculated at 62.2 point with more than half of the respondents, 54.7%, belonging to the range of 60 to 80. When considered by regional groups, the average score of Jin-an was the lowest with 57.6 point while that of Jang-seong was the highest with 69.6 point. In case of the 'cultivation management' category, there were a lot of cultivators who expressed a negative awareness of the term 'pest control' because they had a tendency to think the term in connection with 'herbicides or pesticides'. So it is inevitable to adapt and modify existing groups and grades to make sure that the cultivators can make a right choice without confusing the concept 'pest control' with 'herbicides or pesticides'. Meanwhile, the average scores of 'management and administration' categories were mostly low. It was remarkable in these categories that forestry households in Jeolla province, which had remained in lower ranks in the other three categories, recorded higher scores than those in Chungcheong province, boasting a relatively high level of management and administration.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.155-162
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• 2008

The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.

• Asian Journal of Turfgrass Science
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• v.18 no.4
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• pp.221-229
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• 2004

Biological control of lepidopterous insect pests, Agrotis segetum, Artogeia rapae, Mamestra brassicae, Plutella xylostella, Spodoptera exigua, and S. litura with entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae isolated from Gyeongbuk province were investigated. Mean lethal concentration ($LC_50$) values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of A. segetum larvae were $1.2\times10^7\;conidia/m\ell$ and $5.2\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of A, rapae larvae were $1.2\times10^7\;conidia/m\ell$ and $5.2\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of M. brassicae and P. xylostella, larvae were $1.5\times10^6\;conidia/m\ell$, $9.7\times10^5\;conidia/m\ell$, $3.0\times10^6\;conidia/m\ell$ and $1.4\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of S. exigua, and S. litura larvae were $6.3\times10^6 \;conidia/m\ell$, $2.6\times10^6\;conidia/m\ell$, $1.6\times10^7\;conidia/m\ell$ and $3.4\times10^6\;conidia/m\ell$ respectively.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.1
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• pp.37-42
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• 2021

Munseom (Island) is known as the largest native Elaeocarpus sylvestris var. ellipticus in Korea. Recently, disease damage from the E. sylvestris var. ellipticus community has been reported in Munseom. This study was conducted to understand the damage situation and growth characteristics of the E. sylvestris var. ellipticus population in Munseom. The purpose of this study was to evaluate the spontaneous regeneration potential of the community by grasping the characteristics of the population of surviving E. sylvestris var. ellipticus individuals, and to discuss ways to restore native habitats. A total population survey was conducted to determine the distribution status of E. sylvestris var. ellipticus individuals. The field survey carefully recorded the height of tree, DBH, DRH, and growing status, along with GPS location information of the individual. The growth status of E. sylvestris var. ellipticus individuals distributed in Munseom and the characteristics of tree height, DBH, DRH of each individual were analyzed. The total number of E. sylvestris var. ellipticus populations identified in Munseom was 293. The dense E. sylvestris var. ellipticus community reported in 2005 has been identified as being greatly damaged or damaged. In particular, the damage was more serious in mature trees with a height of 6m or more forming the canopy layer in the forest, and it was confirmed that 80.6% of the mature trees died. In the growth characteristics of the old-growth tree, which is an indicator of the health of the forest based on DRH, 75.4% died or the growth condition was found to be poor. In order to restore the native habitat of E. sylvestris var. ellipticus in Munseom, conservation efforts such as pest control, preservation of mature trees, control of the territory of young trees, and reintroduction after ex-situ transplantation etc. are considered necessary.