• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.39-46
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• 2005

The 21 strains of Korean entomopathogenic nematodes, {Heterorhabditis bacteriophora Hamyang strain(HbH), Heterorhabditis sp. 202, 205, 217, Heterorhabdiris sp. KCTC 0991BP strain, Steinernema carpocapsae Pocheon(ScP), S. longicaudum Gonaju, S. longicaudum Nonsan, Steinernema sp. 7,24, 52, 55, 60, 64, 206, 207, 209, 210, 219, and 227 strain} were evaluated for the control of a turfgrass insect pest, Exomala orientalis. Heterorhabditis spp. showed higher pathogenicity than Steinernema spp. against 3rd instar larvae of E. orientalis with $55\%$ mortality by Heterorhabditis sp. 202 strain and $50\%$ by HbH and Heterorhabditis sp.205 strain at the rate of 200 infective juveniles per larva 14 days later after treatment. The number of infective juveniles of Korean entomopathogenic nematodes in 3rd instar larvae of E. orientalis was higher in Heterorhabditis spp. than in Steinernema spp.. In general, numbers of produced infective juveniles of three species were much higher, i.e., Heterorhabditis sp.202 strain produced 273,064 infective juveniles, S. carpocapsae Pocheon strain 273,043, and Heterorhabditis sp. 217 strain 248,887, respectively.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.233-239
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• 2004

The potential of five entomopathogenic nematodes, Steinernema carpocapsae Pocheon strain, S. logicaudum Nonsan strain, S. glaseri Dongrae strain, Heterorhabditis bacteriophora Hamnyang strain, and Heterorabditis sp. Gyeongsan strain were evaluated as biological control agents against a mushroom fly, Mycophila speyeri in the mushroom, Pleurotus ostreatus cultivation house. Control effect of M. speyeri was significantly different according to nematode species. Heterorhabditis was more effective than Steinernema. H. bacteriophora Hamnyang strain showed the highest control effect representing $49.0\%$ (7 days), $89.5\%$ (14 days) and $89.1\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $46.5\%$ (7 days), $76.6\%$ (14 days) and $85.4\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$ in Changnyoung, Gyeongnam, respectively. In Jinju, Gyeongnam, control effects of the sa me species were $54.0\%$ (7 days), $74.5\%$ (14 days), and $79.8\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $49.0\%$ (7 days), $76.6\%$ (14 days), and $61.1\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$, respectively.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.59-67
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• 2001

The potential of two entomopathogenic nematodes, Sreinernema carpocapsae Pocheon strain and Heterorhabditis bacteriophora Hamyang strain as biological control agents was evaluated against mushroom ny, Lycoriella mali in laboratory and field. Mortality of L. mali was significantly different according to nematode species, concentration, temperature, and developmental stage of fly S. carpocapsae was more effective than H. bacteriophora. Mortality of L. mali was higher at $25^{\circ}C$ than at $20^{\circ}C$. In addition, the 3rd instal and the 4th instar of L. mali were more susceptible than the 2nd instar. The lowest $LC^{50}$ value was represented by S. carpocapsae, 20.0 infective juveniles (Ijs) in the 3rd instar, 27.5 Ijs in the 4th instar at $25^{\circ}C$. S. carpocapsae infected all the developmental stages of L. mali except egg stage and the 1st instar of larva. The highest mortality was shown in adult female representing 74.0% at$20^{\circ}C$ and 80.0% at $25^{\circ}C$.L. mali female adult was influenced by S. carpocapsae in oviposition. The number of eggs by L. mali female infected by nematodes was much lower than uninfected females. S. carpocapsae was dispersed by infected L. mali adult with higher numbers by females than males. When S. carpocapsae was applied at the rate of $2.25{\times}10^{5}\;and\;4.5{\times}10^{5}\;Ijs/1.5\;\textrm{m}^2$ in the mushroom house, mortalities were 42.2% and 81.6%, respectively. The infective juveniles of nematodes survived for 14 days in the mushroom medium. However, nematodes did not affect mushroom growth.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.69-76
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• 2001

The entomopathogenic nematodes, Steinernema carpocapsae Pocheon strain (ScP) and Heterorhabditis bacteriophora Hamyang strain (HbH) were evaluated against chestnut insect pests, The farmers＇handling methods of chestnuts were taken into consideration to develop practical biological control with entomopathogenic nematodes . The major insect pests found with chestnuts were Curculio sikkimensis, Seichocrocis punctiferalis, and Cydia kurokoi. Although individual chestnut contained one species of insect was 58% representing 18% by C. sikkimensis, 27.7% by D. punctiferalis and 12.3% by C. kurokoi. The percentage of co-infection of C. sikkimensis with D. punctiferalis was 3.3%, C. sikkimensis with C. kurokoi 5.0%, D. punctiferalis with C. kurokoi 7.7%, and C. sikkimensis with D. punctiferalis and C. kurokoi 5.0%. The entomopathogenic nematodes, ScP and HbH were effective against all the species of chestnut insect pests. The $LC_{50}$ of ScP was 14.6 for C. sikkimensis, 4.6 for D. punctiferalis, and 5.6 for C. kurokoi and that of HbH was 49.2 for C. sikkimensis, 5.8 for D. punctiferalis, and 13.9 for C. kurokoi, respectively. When ScP was applied into pot including harvested chestnuts at the rate of 4,813 infective juveniles (Ijs)/pot $(=1\times10^9/ha)$, mortality of C. sikkimensis, D. punctiferalis, and C. kurokoi was 85.3%, 96.9%, and 68.1%, respectively. The mortality of C. sikkimensis, D. punctiferalis, and C. kurokoi was 60.73%, 96.5%, and 66.8%, respectively when HbH was applied at the same rate. Combination of two nematode species produced similar effects and insects were more infected by ScP than HbH. When chestnuts were soaked in the suspension of ScP at the rate of 300, 3,000, and 30,000 Ijs for 10 minutes or 30 minutes, mortalities of all chestnut insects were high irrespective of soaking time, concentration , and nematode species.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.245-252
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• 2001

Entomopathogenic nematodes were effective in the control of the cotton caterpillar, Palpita indica Saunder. P. indica mortality was significantly different depending on nematode species, treatment concentration, and instar. S. carpocapsae Pocheon strain was more effective against P. indica than S. glaseri Dongrae strain, S. longicaudum Nonsan strain, Heterorhabditis sp. Gyeongsan isolate, and H. bacteriophora Hamyang strain. When S. carpocapsae was treated with the rate of > 20 infective juveniles (ijs)/larva, mortality was ca. 100% at the 1st-4th instars of P. indica in 72h. $LC_{50}$ of entomopathogenic nematodes were significantly different depending on nematode species. The lowest $LC_{ 50}$ value was obtained by S. carpocapsae with 4.9-8.2 ijs in the 1st-prepupa while the highest $LC_{50}$ by Heterorhabditis sp. with 5.5-21.9 ijs, the shortest LT$_{50}$ value of P. indica was induced by S. carpocapsae when 20 ijs/larva were inoculated. The $LT_{50}$ s were 3.4-9.2h against the 1st-prepupa. The mortality of P. indica in fields was significantly different depending on field condition, nematode concentration, and leaf location. Mortality of P. indica by S. carpocapsae was higher at greenhouse,$ 3$\times$10^{9}$ ijs/ha and upper leaves than at field, 1$\times$10$^{9}$ ijs/ha and lower and middle leaves, respectively.