• The Korean Journal of Soil Zoology
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• v.2 no.2
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• pp.76-82
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• 1997

Mortality of some agro-forest insect pests, Agrotis segetum, Blitopertha orientalis, Agerastica coerulea, Glyphodes perspectalis and Acantholyda parki caused by entomopathogenic nematodes was investigated in laboratory and in pot. Steinernema carpocapsae All and Pocheon strain were effective against 2nd of 3rd instar larvae of A. segetum showing 100% mortalities at the concentration of 10Ijs/larva but not effective against 4th inster larvae. Mortality of B. orientalis was 100% after 26 days in H. bacteriopora NC 1, H. bacteriophora Hamyang and S. glageri NC strain treatment. S. monticulum also showed 100% mortalities against A. coerulea andd G. perspectalis at the concentration of 80 and 40 Ijs/larva. However, H. bacteriophora Cheju and S. glaseri Cheju strain were not effective against A. parki, i.e., showing 23.3 and 20.0% mortalities, respectively at the concentration of 160Ijs/larva. S. glaseri Hanrim strain was more effective than H. bacteriophora Cheju strain against Pryeria sinica.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.21-30
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• 2005

Feeding behavior of foraging ants including visiting numbers, species, and preference on insect cadavers killed by entomopathogenic nematodes <(Heterorhabditis sp. KCTC 0991BP (He) and Steinernema carpocapsae KCTC 0981BP (Sc)> and their symbiotic bacteria was investigated in Dongrae Benest Golf Club, Anyang Benest Golf Club, Gapyung Benest Golf Club and Ulsan Golf Club. The number of ants, kinds and numbers of cadavers taken away by ants were different depending on killing method, golf club and site within the golf courses (fairway and rough). The feeding preference of ants was the lowest on cadavers killed by He. At Dongrae Benest Golf Club Lasius japonicu ($75{\pm}5\%$) and Monomorium floricola ($10\%$) took away cadavers only at the rough. The visiting rate of ants was $85{\pm}6\%$ at the rough, but none at the fairway by 16 hours. The taken rate of cadavers by ants was the lowest on He-killed cadavers representing $16.7\%$ compared with $40.0\%$ on Sc-killed cadavers, $53.3\%$ on fenitrithion-killed cadavers, and $56.7\%$ on natural dead cadavers by 12 hours. At the rough of hole 6 in Anyang Benest Golf Club, Tetramorium tsushimae ($33{\pm}12\%$), Pheidole fervida ($17{\pm}15\%$), Camponatus japonicus ($10\%$), Formica japonica ($7{\pm}6\%$), Paratrechina flavipes ($3{\pm}6\%$), and Crematogaster matsumurai ($3{\pm}6\%$) took away cadavers, but $23{\pm}15\%$ of cadavers were not visited by ants. Ants took away $40\%$ of Sc-killed cadavers, $16.7\%$ of frozen-killed cadavers, and $3.4\%$ of He-killed cadavers. The number of visiting ants was low at the hole 9 of Cherry course in Gapyung Benest Golf Club and only Tetramorium tsuhimae and Paratrechina flavipes were found from one site. The density of entomopathogenic nematodes did not influence ant visiting on cadavers, but burying affected ant visiting. Although ants took away unburied cadavers, buried cadavers were taken away at the hole 6 of Dongrae Benest Golf Club by 16 hours. Ant visiting had the same tendency on symbiotic bacterium-treated biscuit as nematode-killed cadavers. The visiting was less on biscuit inoculated by Photorhabdus sp., a symbiotic bacterium of He than on biscuit inoculated by Xenorhabdus nematophila, a symbiotic bacterium of Sc.

• KSBB Journal
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• v.15 no.1
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• pp.106-111
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• 2000

Peach fruit month, smaller tea tortrix, and Melotontha incana are major pests of apple and apple trees throughout the country. In this work, we examined efficacies of entomopathogenic nematodes Steinernema carpocapsae and Steinernema glaseri against these apple pests. Steinernema carpocapsae showed 100% mortality after 24hr against peach fruit moth when it was applied on the larva with the concentration of 80 nematodes per larva, but Steinernema glaseri caused 83.3$\pm$5.8% mortality after 24hr at the concentration of 50 nematodes per larva. In the case of smaller tea tortrix, S. carpocapsae and S. glaseri caused 100%, 43.3$\pm$5.8% at the concentration of 50 nematodes per larva after 48 hr, respectively. However, 5~6 instar of Melotontha incana was not killed by treatments with S. carpocapsae and S.glaseri up to concentration of 200~800 nematodes per larva. The motility of nematodes in a soil increased as both inoculation concentration of nematode per larva and temperature increased. The mortality of G. mellonella by S. carpocapsae was 100% up to 10cm in depth and 56.7$\pm$5.8% at 10~15cm in depth when the temperature was $25^{\circ}C$ and 50 nematodes per larva were used.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.269-277
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• 2002

Ecological studies on entomopathogenic nematodes are required to increase control efficacy against target insect pests and to obtain basic information for mass production. Thus, effect of temperature and nematode concentration on infectivity and reproduction of Steinernema carpocapsae Pocheon and that of exposure time and soil depth on infectivity were examined using Galleria mellonella larvae. Infectivity and reproduction were examined at five temperatures, 13, 18, 24, 30 and 35$^{\circ}C$ with seven concentrations, 0, 5, 10, 20, 40, 80 and 160 infective juveniles (IJs)/larva. Temperature and nematode concentration influenced infectivity and reproduction of S. carpocapsae Pocheon. Although G. mellonella larvae were killed by S. carpocapsae Pocheon at all given temperatures and nematode concentrations, mortality was higher at 24$^{\circ}C$ than other temperatures. Lethal time of G. mellonella by S. carpocapsae Pocheon was shorter with increasing temperature and nematode concentrations. S. carpocapsae Pocheon was not established in G. mellonella at 13 and $35^{\circ}C$. Time for the first emergence from G. mellonella cadaver was longer $18^{\circ}C$ (about 20 days) than 24 and $30^{\circ}C$ (about 5 days). The highest number of progenies was obtained at $24^{\circ}C$ with 80IJs/1arva, i.e., $18.8$\times$10^4$IJs were produced from a larva. In the exposure time assay, G. mellonella death was recorded in 10 minutes when 300 IJs were inoculated per larva. When S. carpocapsae Pocheon was inoculated at the rate of $10^{9}$ IJs/ha to G. mellonella at the depth of 0, 2, 5 and 10 cm of sand columns, 100% mortality and similar sex ratio were observed but number of established IJs in cadaver was decreased with deepening the soil depth. The results indicated that optimum temperature for infectivity and reproduction of S. carpocapsae Pocheon was $24^{\circ}C$ In addition, S. carpocapsae Pocheon was effective to target insects within 5 cm from the soil surface.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.730-735
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• 2003

The effect of pathogenicity on trehalose accumulation was studied using six species of entomopathogenic nematodes adapted to either cold or warm temperature conditions. Also, trehalose accumulation was studied by treating nematodes with glycerol or oil at trehalose concentration and mortality of cold temperature $condition(5^{\circ}C)$, S. longicaudum Gl was increased 50% than control. And at trehalose concent and mortality of warm temperature $condition(30^{\circ}C)$, S. glaseri Agr B3 was increased 45%. Intracellular trehalose accumulation was increased with treatment with 20% glycerol or oil. As the final results, the pathogenic duration of nematodes was increased as intracellular trehalose accumulation was increased

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.60-68
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• 1999

Effects of temperature and dose-size on infectivity and reproduction of Korean entomopathogenic nematode, Steinernema longicaudum Gongju strain were examined. The greater wax mea Galleria mellonella larvae were exposed to 5, 10, 20, 40, 80, and 160 infective juveniles/larva in $60{\times}15$ mm petri dishes and kept in $13^{\circ}C$, $18^{\circ}C$, $24^{\circ}C$, and $30^{\circ}C$ incubators. Each petri dish contained one larva weighed from 180 to 200 mg. Infectivity was observed everyday for 14 days and reproduction for 30 days. The infectivity of S. longicaudum was more influenced by temperature than by dose-size. Mortalities by S. longicaudum were lower at $13^{\circ}C$ at all concentrations but higher at $24^{\circ}C$ and $30^{\circ}C$ even at lower concentrations, 5 or 10 infective juveniles/larva. Lethal time was also shorter with increasing temperature and dosages. All host larvae died at $24^{\circ}C$ and $30^{\circ}C$ in 2 days at the rate of 160 infective juveniles per host while 83.3% of tested larvae died at $24^{\circ}C$ in 10 days and 90% at $30^{\circ}C$ in 6 days at the rate of 5 infective juveniles. Reproduction was also better with increasing temperature and dosages. The highest number of progenies was obtained at $30^{\circ}C$ in 6 days at the rate of 80 infective juveniles. However, progenies were not produced from cadavers at $13^{\circ}C$. Reproductive period was the shortest at $30^{\circ}C$ of all temperatures by 6 to 9 days. The results indicated that optimum temperatures for infectivity was $24^{\circ}C$ and $30^{\circ}C$ for reproduction.

• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.17-25
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• 2005

Pathogenicity of entomopathogenic nematde, Steinernema carpocapsae Pocheon strain (ScP) was evaluated against different larval stages(2nd, 3-4th and 5th) of Anomis commode and Anomis mesogona(Lepidoptera: Noctuidae) in petri dish and pot. The $LC_{50}$ values were increased in proportion to larval stage of A. commoda and A. mesogona. $LC_{50}$ value of ScP against 2nd instar of A. commoda and A. mesogona was 9.7 and 4.5, respectively. The 2nd instar of both species was also susceptible to ScP in pot test. That is, mortality of 2nd instar of A. commode and A. mesogona was higher representing $72.5\%\;and\;87.5\%$ 5 days later after treatment, respectively, when ScP was applied at the ,ate of 90,000 infective juveniles(Ijs) per $pot(=1\times10^9\;Ijs/ha)$. However, susceptibility was decreased from 3rd instar. Mortality of 5th instar of A. commoda and A. mesogona was $5.0\%\;and\;10.0\%$, respectively, at the rate of 90,000 Ijs/pot. When ScP was applied into pot including mixed larval stages from 2nd to 5th instar(10 larvae far 2nd instar, 10 larvae for 3rd - 4th instars, and 10 larvae for 5th instar) at the rate of 90,000 Ijs/pot, mortality of A. commoda and A. mesogona was $69.2\%\;and\;50.0\%$, respectively.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.117-125
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• 1998

Entomopathogenic nematodes, Heterorhabditidae and Steinernematidae, were isolated from the soil of mulberry field, and the high infectivity and invesiveness were confirmed in the silkworm, Bombyx mori. The cause of non-microbial and acute flacherie was found as an disease by infection with soil-born nematodes through the mulberry leaves contaminated with soil and rainwater. The causal nematodes were isolated by silkworm trap from all of the 5 soil samples collected on the 5 mulberry fields, and identified as 3 strains of Heterorhabditis sp. and 2 of Steinernema sp. Rainwater itself, however, wasn't engaged in the silkworm disease, mulberry leaves with rainwater was rather profitable for cocoon production when the leaf quality was too hard to feed silkworm. Feeding of wet mulberry leaves with rain might not so harm to silkworm when the condition of rearing room to be kept at suitable temperature and ventilated well. Nematode infection of silkworm could be occurred by harvesting and feeding of contaminated mulberry leaves on the weather condition of rainy and wind. For the prevention of nematode infection, silkworms should be fed the leaves harvested from the higher portion of the mulberry tree in rainy days. For an oppositional application of this susceptibility of silkworms to nematode, might be useful on the collection and amplification of nematode agents for biotic control of pest insects.

• KSBB Journal
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• v.13 no.1
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• pp.31-37
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• 1998

A simple method for the in vivo production of third-stage infective juveniles(IJs) of Steinernema glaseri was developed. Using Galleria mellonella larvae, only IJs can be rapidly generated inadequate quantities for field application. The nematode inoculation concentration and incubation temperature were critically important. The most effective temperature for infectivity of Steinernema glaseri IJs to Galleria mellonella larvae was 33$^\circ C$. However, the total number of menatodes harvested at 25$^\circ C$ about 66,000 IJs per larva was significantly greater than those at other temperatures. The optimal inoculation number of nematodes was 60 to 80 nematodes per host larva. The higher nematode inoculation concentration of 100 IJs per larva caused a rapid decrease in the total number of IJs harvested. As the inoculation medium pH increased, the number of IJs harvested increased and reached about 110,000 IJs per larva at pH 9.0. The pathogenicity of IJs decreased y increasing the salt concentration in the medium.

• Asian Journal of Turfgrass Science
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• v.13 no.4
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• pp.213-222
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• 1999

The toxic effects of four pesticides on the entomopathogenic nematodes. Heterorhabditis bacteriophora NC strain, Steinernema glaseri NC and Dongrae strain were tested by checking the mortality of infective juveniles(Ijs) in aqueous solution of pesticide. Mortality of Ijs was influenced by pesticide and concentration and soaking time. The herbicide alachlor and insecticide fenitrothion were toxic to Ijc of three entomopathogenic nematodes. But, the fungicides mepronil and tolclofos-methyl were nontoxic to Ijs. Tolclofos-methyl showed significantly very week toxicity at 28 days after soaking for S. glaseri NC strain. H. bacteriophora NC strain was more highly sensitive to high temperature condition then were the other nematodes.