• Korean journal of applied entomology
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• v.43 no.1
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• pp.81-84
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• 2004

Plant-parasitic nematodes were surveyed at peach orchards in Gyeongbuk province for three years from 2000 to 2002. Species, density, frequency, Simpson's index, Shannon and Wiener index, and prominence value were analyzed. Plant-parasitic nematodes were isolated from 97 orchards out of 124 orchards. More important plant-parasitic nematode genera on peach were Tylenchorhynchus nudus, Criconemoides informis, Paratylenchus elachistus, Pratylenchus vulnus, and Helicotylenchus digonichus. Aphelenchus sp., Tylenchus sp., Heterodera sp., Scutellonema sp. were found, but were not important. Root-knot nematodes were not found even though they were serious in foreign countried.

• Korean journal of applied entomology
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• v.29 no.1
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• pp.14-19
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• 1990

Nematodes and insects associated with dead trees were surveyed on the 238 dead trees belonging to 19 tree species in Pusan, Gyeongnam, Gyeongbuk, Chunnam, and Chonbuk provinces from April to September of 1989. Pine wood nematode, Bursaphelenchus xylophilus was found only in Pusan but B. mucronatus was collected at Chinju and Chinhae. The 13 nematode species in 9 genera were identified. Out of them, Diplogasteroides dimidius, Rhabdontolaimus adephagus, R. janae, Mikoletzkya diluta, M. ruminis, M. langcaudaa, Parasitorhabditis hylurgi, Panagrolaimus concolor, Panagrodontus dentatus, Prothalonema intermedium, and marcrolaimus canadensis were recorded for the first time in Korea. Insects collected from dead trees were 5 orders, 9 families, 25 genera, and 27 species. of them, the Coleoptera were the most collected insects by the 3 families, 19 genera and 22 species. The Scolytidae were 12 species in 10 genera. Hypothenemus eruditus was firstly collected from Campylotropis macrocarpa, Lespedeza maximowizi, Forsythia ovata, Meliosma oldhami, Securinega suffruticosa, Broussonetia kazinoki, and Cornus walteri. The maximum number of pine wood nematode was separated from the abdomen of Monchamus alternatus, the pine woodnematode vector. The maximum number of nematodes per an adult of M. alternatus was 127,535, minimum 2,616, and average 42,817.

• Korean journal of applied entomology
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• v.27 no.3
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• pp.149-158
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• 1988

Nematophagous fungi were successfully isolated by baited plating, centrifugation technique of soil, and direct isolation from naturally ingested nematodes. Predominant seven fungi isolated were identified as Artheobotrys arthroboteyides, A.conoides, A. oligospora, Dactylella lobata, Fusatium oxysporum, Monacrosporium ellopsoporum and Harposporium anguillu-lae. Of these, six fungi were tested for cultural characteristics except. H, anguillulae, extre-mely fastidious fungus in artificial media. Among 14 media tested in this experiment, Corn-meal Agar (CMA) and Oatmeal Agar (OMA) were the most suitable media for growing all six nematophagous fungi. Weakly saprophytic M. ellipsospoyum also grew vigoroualy on these two media. The radial growth, dry weight and sporulation of the fungi tested were quite diverse depending on the culture media. D. lobata revealed good growth and abundantly sporulated on Glucoes Peptone Agar (GPA). Although over-all growth of F, oxysporum was not satisfactory on Sucrose Nitrate Agar (SNA), the sporulation was best on this medium. Optimum conditious for mycelial growth and sporulation of nematophagous fungi ranged pH 5-8 and 20-$30^{\circ}C$ on SNA. D. lobata and F, oxysporum grew vigorously and most profusely sporulated on all media tested. They turned out an most promising biocontrol agents for their aggressive growth and sporulation over the ranges of temperature and pH ranges.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.910-913
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• 2001

The fatty acid compositions of entomopathogenic nematodes Steinernema carpocapsae strain produced in vitro and in vivo were examined. Nematodes cultured both in vitro and in vivo revealed similar fatty acids compositions with respect to 16, 18, 20 carbons. However, the contents of lipids were varied by culture methods. Furthermore, it was distinctive that nematodes cultured in vitro contained fatty acids with 19 carbon. In the case of symbiotic bacterium Xenorhabdus nematophilus isolated from Steinernema carpocapsae, the major lipid component was palmitic (c16:0) fatty acids.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.271-275
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• 2003

The direct count and MPN (Most Probable Number) methods were used to measure the number of nematodes in soils collected from cultivated and non-cultivated fields. As a result, the number of nematodes from cultivated soils was higher than the non-cultivated soils (NC -1, NC -2). On the other hand, upon measuring the value from the organo farming cultivated soils (OC, OR) and conventional cultivated soils (CC, CR), the former showed 16 times higher than the latter. These results indicate that nematode population which can multiply in the organic compounds abundantly exist in the organo farming cultivated soil. Isolated entomopathogenie nematodes are composed of two orders, which were Rhabditida and Diplogasterida. To determine the pathogene-city of them using the 5th larvae and pupae silkworm, and the following mean $LD_{90}$ values were found: 24 to 30 hours in Rhabditida and 36 to 48 hours in Diplogasterida nematode, respectively. This study indicates that nematodes are sensitive to this kind of environmental disturbance. Isolated entomopathogenic nematodes were suggested that aye quite within the realms of possibility for biological control agents.

• Journal of Life Science
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• v.10 no.4
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• pp.403-407
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• 2000

For the biological control of the root-lesion nematodes, Pratylenchus spp., which damage directly and indirectly to the leaf perilla, the nematical effect of three nematode-trapping fungi, Arthrobotrys oligospora, A. conoides and A. dactyloides was evaluated in the field. Three species of Arthrobotrys were isolated from the culture soil of leaf perilla in 1998 and were observed the capture of the root-lesion nematodes, Pratylenchus spp. by adhesive hyphal networks or constricting rings on agar. At 40 days after treatment, the plant-parasitic nematodes and root-lesion nematode populations were approximately increased 3.5 fold in untreated control plot, while the nematode population in fungi treatment plots was similar to initial population. In the A. dactyloides plot, however, the population of plant-parasitic nematodes and Pratylenchus spp. was approximately reduced 65% and 53%, respectively. Thus, the fungus A. dachyloides should provide as biological agent for the control of Pratylenchus spp.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.162-168
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• 2012

An nematophagous fungi Arthrobotrys thaumasia Nema-1 and Bacillus subtilis C-9, which degrade the collagen and gelatin, were isolated from horticulture plantation soil in Kyungpook Sungju-gun Seonnam-myun and Chungnam Gongju-gun Woosung-myun to develop biological nematode pesticide. When $5,000mg\;kg^{-1}$ of A. thaumasia Nema-1 nematicide powder ($7.0{\times}10^3cfu\;g^{-1}$) was treated to pot including Meloidogyne incognita, the number of nematode's egg mass, which is a index of nematicidal activity, decreased to 35% compared to control. While the number of nematode's egg mass decreased to 67% by treating the nematicide powder mixture of $5,000mg\;kg^{-1}$ Nema-1 and B. subtilis C-9 ($8.5{\times}10^5cfu\;g^{-1}$). Furthermore the number of nematode's egg mass of the mixture containing cinnamon extract $10mg\;kg^{-1}$, each $5,000mg\;kg^{-1}$ of Nema-1 and C-9 nematicide powder was decreased to 84%, comparing to the result showed the number of nematode's egg mass decreased to 24%, by the treatment of chemical nemato pesticide Fosthiazate $24mg\;kg^{-1}$. These results suggested the mixture of microorganisms and plant extract was more effective biological nematicide than the case of only microorganism or plant extract for nematode control.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.228-235
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• 2011

An nematophagous fungi Arthrobotrys thaumasia Nema-1 and Pseudomonas putida C-5, which degrade the collagen and gelatin, was isolated from controlled horticultural soils in Seonnam-myun, Sungju-gun, Kyungpook and Woosung-myun, Gongju-shi, Chungnam to develop biological nematode pesticide. When $5,000mL\;L^{-1}$ of A. thaumasia Nema-1 culture was treated to Meloidogyne incognita, the nematicidal activity resulted in 55% at 72 hours after treatment. While the nematicidal activity increased to 65% by treating the culture mixture of $5,000mL\;L^{-1}$ Nema-1 and P. putida C-5 after 72 hours. Furthermore, the nematicidal activity of the mixture containing cinnamon extract $50mg\;L^{-1}$, each $5,000mL\;L^{-1}$ of Nema-1 and C-5 culture was elevated to 89% at 72 hours after treatment, comparing to the result showed 17% and 57% of the nematicidal activity, respectively by the treatment of chemical nemato pesticide Fosthiazate $50mg\;L^{-1}$ and neem oil $2,000mL\;L^{-1}$. These results suggested that the mixture of microorganisms and plant extract were more effective biological nematicide than the case of only microorganism or plant extract for nematode control.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.97-101
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• 2008

For the isolation of Actinomycetes showing nematocidal activity against Pine wood nematode, Bursaphelenchus xylophilus, about 2000 culture broth of Actinomycetes were tested and their activity were compared with that of Streptomyces avermitilis resulting a selected strain AW050027. The cultural, morphological and physiological analysis was performed for the identification of a selected strain. Phylogenetic analyses based on 165 rDNA gene sequences showed that the selected strain AW050027 belonged to the genus Micromonospora and M. corioriae $NAR01^T$ was the closest neighbors, sharing 98.9% 165 rDNA gene sequence similarity.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.255-263
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• 1999

Entomopathogenic nematodes were isolated through the investigation of soil samples from various biotopes in south Korea, the efficiency of isolation for highly pathogenic nematodes to silkworms (Bombyx mori) was as high as 28 %. Twenty-eight strains of nematodes, selected among 100 samples by silkworms were confirmed the pathogenicity, multiplicity, and tolerance against various condition of preservation. Pathogenicity of the nematode isolates to agricultural and environmental pests such as Calliphora vomitoria, Pseufaletia separata, Palomena angulosa, and Melolontha incana were high. Mortality was varied from 20 to 100% by the pest insects and nematode strains. The high detectablity of entomopathogenic nematodes resulted from the methods of collection for soil samples within 10 cm depth after eliminating dried soil surface and the use of silkworm trap. High population of entomopathogenic nematodes represented the strong activity and broad action radius in the environment. Most of the nematode isolates were successfully cultured on the silkworm host as well as on artificial media, and proved their potential for the use of biological control agent.