• Research in Plant Disease
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• v.22 no.4
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• pp.249-256
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• 2016

To investigate the incidence of plant-parasitic nematodes from plastic-house fields of strawberry, 170 soil samples were collected from the main producing area of strawberry in Korea from 2014 to 2015. Based on the investigation, root-lesion nematode (RLN; Pratylenchus spp.) and root-knot nematode (RKN; Meloidogyne spp.) are the most important pests in plastic-house fields of strawberry with 57% and 36% incidences, respectively. Among the collected fields, 96 and 63 fields were infected RNL and RKN, respectively with 44 fields (38.8%) being detected at both nematode. High degree of incidence of both nematodes were observed in the regions of Jinju, Gyeonnam Province, Korea. For identification of species level, phylogenetic and distance analysis were performed using RLN and RKN isolates generated from the regions of Jinju. The results indicated that the RLN and RKN isolates were Pratylenchus vulnus and Meloidogyne hapla, respectively. This study showed that P. vulnus and M. hapla could be most dominant species in plastic-house fields of strawberry. This data will provide basic knowledge for development of effective control strategies.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.212-220
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• 1980

The purpose of this study is to establish a standard amount of pesticide per unit area of the lumber over the sea level. This establishment is required in applying the sea water dipping disinfection method to the imported soft woods to control the pests living on the surface of the lumber. The major findings of this study are as follows; 1. The average length and diameter of the imported soft wood was respectively 11.12m and 76.46Cm. 2. The average cubic content of the lumber over the sea level to the whole cubic content was 20.82 percent. 3. The ratio of the lumber over the sea level to the whole cubic content was 2.3356 at the $95\%$ significance level. 4. The sampling error of the ratio of the area of the lumber over the sea level to the cubic content was lower in the case of the pieces of lumber in a vessel than the average between ten tressels. 5. The optimum amount of pesticide spray per $1\;M^2$ of the soft wood was 0.298 cc in the case of using the hand spray, but 0.245 cc the motor spray. 6. For example, in the case of applying the sea water dipping disinfection method to the 5,000 $M^3$ of the imported soft wood, the required amount of pesticide with a motor spray can be estimated as follow. $$5,000\;M^3\times2.333=11,678\;M^2$$ $$11,678M^2\times0.295=3,445cc$$.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.189-196
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• 2020

Mosquitos serve as vectors for diseases, causing inconvenience as well as a threat to human life and health. Concern about mosquitos introducing and spreading new diseases has been intensifying. We observed a variety of mosquito habitats based on land cover classification from Korea's Ministry of Environment, and the mosquito species that could appear were classified according to the each habitat type. Finally, we suggested the best control methods for each type of habitat considering habitat characteristics and the ecological traits of mosquitos. Urban areas harbor various habitats for pests, contributing significantly to mosquito habitats. Control must be performed regarding larva and adults because various sources for habitats exist. Public mosquito control programs such as educational training, as well as information brochures can be effective in managing mosquito populations and public health. Agricultural areas show high densities of mosquito larva to lentic zones such as reservoirs, wetlands, paddy fields. So, biological control using natural predators may be effective in controlling mosquito populations. Forests are major habitats for Aedes albopctus, so physical controls should be deployed for residents living nearby, and excessive deforestation should be minimized. Other areas including aquatic ecosystems should be adopted regarding biological control using Bti (Bacillus thuringiensis var. israelensis) and chemical control for eradicating mosquitos. We classified habitats into four types of land cover patterns considering ecological traits and habitat preference, and suggest adequate control methods for each habitat type. Our suggestion can be used to positively contribute toward effective managing mosquito's density and reducing the damage to public health.

• Weed & Turfgrass Science
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• v.6 no.2
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• pp.136-150
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• 2017

Zoysiagrass mite, Aceria zoysiae is one of the main turfgrass pests causing significant damage on zoysiagrass. In this study we investigated damage by zoysiagrass mite for the selection of zoysiagrass mite-resistance turfgrass individual in natural collected turfgrass isolates transplanted in genetic resources conservation area. In the results of investigation of 295 turfgrass isolates collected from Korea, damage level was different depending on turfgrass species and individuals. Zoysia japonica was highly damaged representing 97.6%, followed by hybrid zoysia and Z. sinica with damage percentages of 87.7% and 81.1% respectively. Additionally, 2 individuals of Z. macrostachya were also damaged by zoysiagrass mite. However several individuals were not damaged by zoysiagrass mite in green house and field. Damage by zoysiagrass mite was occurred from May and peak at after July in field. The study highlighted some important resistant turfgrass individuals which can be used in the management of zoysiagrass mite.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.189-197
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• 2004

Alpine and sloped-land in Gangwondo, Korea is the most important land type for cultivation of Chinese cabbage. However, farmers in these regions have major problems with insect pests, weeds and disease. Over use or inappropriate use of agrochemicals occurs frequently. No intensive study of pesticide contamination in this area has been done. The work presented in this paper addresses this deficiency. We measured pesticide residues within soil and water samples using multiresidue analysis. Samples were collected bimonthly from April to October, 2002 at three sites with to sampling spots. At the three sites, Pyeongchang, Jeongseon and Taebaeck, pesticides most frequently detected (>30% of samples) in soil samples were endosulfan, fluazinam, diniconazole, alachlor, prothiofos and dimethomorph. The amount of pesticide residues in the soils was ranged from 0.004 to $0.412\;mg\;kg^{-1}$ in these samples. Non-registered pesticides were also detected in these samples, indicating illegal use of pesticides. No pesticide were detected in the water samples collected from those sites. The results showed that pesticide residues might be dependant on physiochemical properties of pesticides, application history and soil properties. This study provides basic data for appropriate pesticide use on alpine and sloped-land in Korea.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.4
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• pp.7-20
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• 2004

This study was executed to find out how to improve the planting and use of landscaping plants in Chuncheon. The number of street trees was 17,877 in 2003. The major species of street trees were Ginkgo biloba(52.7％), Prunus sargentii(15.3％), Zelkova serrata(8.9％), Platanus occidentalis(7.3％). Salix babylonica and Platanus occidentalis were decreased, while Prunus sargentii and Zelkova serrata were increased. Salix babylonica is a good species for a lakeside city, but its seeds cause allergies to some people. Most of the trees have been removed in Chuncheon. The planting of Salix babylonica(♂) resulted in no problems, and it should be propagated to plant. The soil of several areas was analysed to investigate soil conditions. The outskirts of city had good conditions in pH, organic matter and minerals, but the downtown areas had high alkalic, due to alkali from footpath concrete blocks. Appropriate pruning adds to the aesthetic and prolongs the useful life; it also requires less managing of insects and diseases to maintain good healthy of street trees. Street trees were not properly pruned due to electric lines and shortage of pruning information. The pruning was controlled by Korea Electric Power Co, which has no pruning information. Pruning must be maintained by a professional landscape company to maintain good shape such as with Bonsai. The Shrubs planting zone between street trees and other trees, and preservation plates were established for healthy of street trees. They have to be repaired and maintained well to keep better environmental conditions. The number of tree and flower species of 68 schools in Chuncheon were 12 and 16, respectively. The species that showed high preference were Juniperus chinensis, Pinus koraiensis, Pinus densiflora, Rosa centifolia, Forsythia koreana, and Rhododendron schlippenbachii. The high frequency of the protection trees designated by Chuncheon were Pinus densiflora, Ginko biloba, Zelkova serrata, Quercus species. It was thought that the diversification of street tree species, the selection of street trees suitable to each space, the generalization of use of native species, the appropriate pruning and proper fertilization, the control of pests and diseases, and the opinions of citizens concerning landscape plants were needed to improve the planting, use and maintenance of landscaping plants in Chuncheon.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.145-152
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• 2006

Predation of Neoseiulus fallacis was observed for biological control of Panonychus citri that is one of the major insect pests on citrus. The daily predation of development stages of P. citri by an adult female of N. fallacis were 20.1 eggs, 26.1 larvae, 18.2 protonymphs, and 7.4 deutonymphs at 25$^{\circ}C$, The daily predation of P. citri eggs by N, fallacis was observed under different temperatures. The predation was increased as the temperature rise. At this time, ratio of eggs production of l! fallacis after predation of P. citri eggs (number of eggs N. fallacis/number of eggs P. citri consumed by N. fallacis) was 0.09. The daily predation of P. citri eggs by N, fallacis was 21.1, 17.3, and 16.7 on the different arenas (diameter: 20, 40, and 60 mm), respectively. The predation was decreased as the arena of the leaf increase. The functional response of M fallacis to P. citri showed Holling's Type II response: the consumption of prey by N. fallacis increased as the density of prey increase but increasing rate was gradually reduced. As the result, it seemed that N. fallacis can be use for biological control of P. citri.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.332-335
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• 2008

"Hwangkeumbora" is a new japonica rice cultivar developed from a three way cross of Jinbubyeo, Odaebyeo, Fukei126 at Honam Agricultural Reaserch Institute (HARI), NICS, RDA, in 2006. This cultivar has about 110 days growth duration from transplanting to harvesting under Korean climate condition. The milled kernel of "Hwangkeumbora" is translucent with non- glutinous endosperm. Amylose content of "Hwangkeumbora" is about 19.3%. "Hwangkeumbora" has better palatability of cooked rice compared with "Odaebyeo" and shows high resistant reaction to the blast, but susceptible to major diseases and insect pests. The milled rice yield of "Hwangkeumbora" is about 5.37 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. "Hwangkeumbora" would be adaptable for ordinary transplanting in northern plain, mid-mountainous, southern mountainous of Korea.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.645-648
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• 2009

"Deuraechan" is a new japonica rice variety developed and registered by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2008. This variety was derived from a three way cross Iksan438, YR19105Acp222 and Milyang165. This variety has about 122 days of growth duration from transplanting to harvesting in Honam and Youngnam plain of Korea. It is about 76 cm in culm length and tolerance to lodging. In reaction to biotic stresses, it shows moderately resistance to blast, resistance to bacterial blight pathogen races from $K_1$ to $K_3$, and Rice stripe virus, but susceptible to other major diseases and insect pests. The milled rice of "Deuraechan" has high Quality, midium short grain. The milled rice yield of this variety is about 6.52 MT/ha in local adaptability test for three years. "Deuraechan" would be adaptable to Middle plain, Honam plain and Youngnam plain area of Korea.