• Asian Journal of Turfgrass Science
• /
• v.19 no.1
• /
• pp.39-46
• /
• 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
• /
• v.34 no.4
• /
• pp.314-320
• /
• 1995

Pathogenicity of Korean entomopathogenic nematodes against local insect pests was different depending on strains or target-insect pests. Mortalities of diamondback moth, Plutella xylostella larvae were 51.8%, 77.8%, 96.3% or 100% in Hanrim Steinernema sp. and 50.0%, 74.1%, 96.3% or 98.1% in Hamyang Heterorhabditis sp. on filter paper when larvae were exposed to 3, 6, 12, or 24 nematodes per larva. Mortalities of them on kale leaves at the same concentration were 44.4%, 63.0%, 76.1%, or 94.5% in Hanrim Steinernema sp. and 79.7%, 81.6%, 94.4%, or 100% in Hamyang Heterorhabditis sp., respectively. In field test, control value of Hanrim Steinernema sp. was 72.0% and that of Hamyang Heterorhabditis sp. was 84.1% in 14 days when 300,000 nematodes were sprayed to each plot ($13.27\m^2$). Although mortalities of rice stem borer, Chilo suppressalis larvae showed no difference at high concentration, Hamyang Heterorhabditis sp. (47.3~100%) was more effective than Hanrim Steinernema sp. (34.3~83.3%) at low concentration, 50~200 nematodes/ml. When chestnut curculio, Curculio sikkimensis larvae were treated with Sancheong Steinernema sp. and Hamyang Heterorhabditis sp., respectively. When pellucid zygaenid, Pryeria sinica larvae were exposed to nematodes, Pocheon Steinernema sp. was effective ranging from 96.7% to 100% but mortalities of them were 63.3~76.7% in Dongrae Steinernema sp..

• The Korean Journal of Pesticide Science
• /
• v.10 no.2
• /
• pp.107-116
• /
• 2006

Korean entomopathogenic nematode strain were evaluated against white grubs, Popillia quadriguttata, Ectinohoplia rufipes and Phyllopertha diversa in laboratory. In addition we examined the efficacy of entomopatogenic nematode, Heterorhabditis sp. KCTC 0991BP strain against white grubs in Seaside Golf Club in Gimpo, Gyeonggii and persistence of entomopatogenic nematode in fairway of Anyang Benest Golf Club in Gunpo, Gyeonggii. In laboratory Heterorhabditis bacteriophora Hamyang strain showed 95% mortality against Popillia quadriguttata. H. bacteriophora Hamyang strain and Heterorhabditis sp. KCTC 0991BP induced 80% mortality against 3rd instar of Ectinohoplia rufipes. However, the letter showed only 60% mortality against Phyllopertha diversa. White grub density was reduced to 39% by the application of Heterorhabditis sp. KCTC 0991BP at the rate of $2.24{\times}10^9$ infective juveniles $ha^{-1}$ compared with control in Seaside Golf Club. Heterorhabditis sp. KCTC 0991BP persisted for two months at $5{\sim}10$ cm soil depth but not persisted at $0{\sim}5$ cm soil depth for the same periods when applied at the rate of $2.47{\times}10^9$ infective juveniles $ha^{-1}$.

• Microbiology and Biotechnology Letters
• /
• v.29 no.2
• /
• pp.104-109
• /
• 2001

The yield of infective juveniles of Heterorhabditis bacteriophora (Tf strain) in vitro monoxenic liquid culture was improved significantly as the amount of symbiont biomass, Photorhabdus sp. strain Tf, increased. To investigate the influence of abiotic factors on the growth and biomass production of Photorhabdus sp. strain Tf, triplicate flask cu1tmes were performed. The optinal temperature and medium pH for the growth of Photorhahdus sp. strain Tf were 30$^{\circ}$C and between pH 5.5-7.3, respectively. Aeration also improved greatly growth and yield of biomass of Photorhabdus sp. strain Tf. Photorhabdus sp. strain Tf in batch fermentation showed growth-associated pattem in terms of pigment production, and the pH of culture medium rose steadily until growth stopped dUling the fermentation. Both pigment production and culture pH rise would be useful parameters indicating a reliable growth of Photorhabdus sp. strain Tf.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.8 no.2
• /
• pp.77-85
• /
• 2006

Entomopathogenic nematodes (EPNs) have been used as biological control agents for control of various agro-forest insect pests, and are especially effective against soil-dwelling insect pests. Effect of soil moisture on pathogenicity of commercial EPNs for white grub control was evaluated in laboratory, pots, and golf courses. Pathogenicity of EPNs in sand column was variable depending on depth, soil moisture, and EPN species or strain. All tested EPNs (Heterorhabditis sp. GSNUH1, Heterorhabditis sp. GSNUH2, Steinernema carpocapsae GSN1, and S. longicaudum Nonsan strain) showed similar pathogenicity against the bait insect, great wax moth (Galleria mellonella) larva at 2 cm deep at a given soil moisture. However, pathogenicity of the Heterorhabditis sp. GSNUH1 strain was decreased with increasing soil moisture. Pathogenicity of S. carpocapsae GSN1 strain was the lowest in 3% soil moisture (v/w) at 7 cm depth. However, there was no difference in pathogenicity between Heterorhabditis sp. GSNUH2 and S. longicaudum Nonsan strain. Although pathogenicity of Heterorhabditis sp. KCTC 0991BP strain showed no difference against the 2nd instar of Exomala orientalis, that of the S. carpocapsae GSN1 strain was decreased in the laboratory depending on soil moisture. Highly pathogenic strain EPN, Heterorhabditis sp. KCTC 0991BP strain, showed higher pathogenicity at 100 mm irrigation than non-irrigation or 10 mm irrigation. However, poor pathogenic strain EPN, S. carpocapsae GSN1 strain, was not different in pathogenicity from the 2nd instar of Exomala orientalis in creeping bentgrass (Agrostis palustris) depending on irrigation amount in the pot. Pathogenicity of EPNs in field experiment at the tee of Ulsan golf club showed a similar trend to that in the pot experiment.

• Korean journal of applied entomology
• /
• v.41 no.3
• /
• pp.217-223
• /
• 2002

The chestnut brown chafer, Adoretus tenuimaculatus Waterhouse, is serious insect pests in golf courses. Adults feed on the leaves of latifoliate trees but larvae feed on roots of turfgrases such as bentgrass, Agrostis spp. Damage of A. tenuimaculatus larvae was observed at the Jinju golf club which showed damage symptom on perennial ryegrass, Lolium perenne in tees and fairways in July, 2000. Damaged turf by A. tenuimaculatus larvae became yellowish and wilted. Symptom of laval damage of A. tenuimaculatus was similar to summer depression in warm season turfgrasses but not recovered by irrigation when Korean isolates of entomopathogenic nematodes were evaluated for the control of A. tenuimaculatus larvae in laboratory and field as a possible biological control agent. The nematodes used were Heterorhabditis bacteriophora Jeju strain, Hererorhabditis sp. Gyeongsan strain, Steinernema carpocapsae Pocheon strain, S.glaseri Dongrea strain, and S.longicaudum Nonsan strain. In the laboratory test H.bacreriophora Jeju strain and Heterorhabditis sp. Gyeongsan strain were highly effective for 3rd instars with 95% mortality. In the field test reduction rates of A.tenuimaculatus larvae were higher by ranging from 28 to 57% by H. bacteriophora Jeju strain, Heterorhabditis sp. Gyeongsan strain, and S.carpocapsae Pocheon strain compared to 7% by natural cause.

• The Korean Journal of Pesticide Science
• /
• v.10 no.4
• /
• pp.335-343
• /
• 2006

Five strains of Korean entomopathogenic nematodes(EPN), steinernematids and heterorhabditids(Steinernama carpocapsae GSN1, Steinernema sp. GSNUS-10, Steinernama sp. GSNUS-14, Heterorhabditis bacteriophora Hamyang, Heterorhabditis sp. GSNUH-1) were evaluated and tried in petri dish, pot, and vegetable greenhouses for environmentally friendly control of beet armyworm, Spodoptera exigua. $LC_{50}$ values of five EPN strains against beet armyworm was different depending on nematode strain and beet armyworm instar. $LC_{50}$ value of Steinernema carpocapse GSN1(GSN1) was 3.8-5.1 infective juveniles(Ijs) in 2nd to 4th instars of beet armyworm. Pathogenicity of five EPN strains against beet armyworm different in nematode strain, concentration, application times, and vegetable species in pot and greenhouse. Steinernema spp. was more effective than Heterorhabditis spp. against beet armyworm. Two or three times of applications of EPN were found to be effective regardless of nematode strain and concentration in pot and greenhouse. ENP showed different reactions on vegetable species. Efficacy of EPN was higher on Chinese cabbage than that on cabbage and kale. GSN1 was one of the most effective nematodes and 100,000 infective juveniles per $m^2$(720,000 Ijs/$7.2m^2=1{\times}10^9$Ijs/ha) resulted in higher mortality in greenhouse.

• The Korean Journal of Pesticide Science
• /
• v.20 no.4
• /
• pp.361-368
• /
• 2016

Japanese pine sawyer (JPS), Monochamus alternatus is a vector insect of pine wood nematode, Bersaphlenchus xylophilus in Korea and Japanese pine forest. This study was to evaluate the possibility of biological control of JPS with Korean entomopathogenic nematodes (EPNs). Korean EPNs (Heterorhabditis sp. Gyeongsan, Steinernema carpocapsae GSN1, S. glaseri Dongrae and S. longicaudum Nonsan strain) were infested bate insect, Galleria mellonella in log of dead pine tree. Result showed that, S. carpocapsae GSN1 strain has the highest pathogenicity. Heterorhabditis sp. Gyeongsan and S. carpocapsae GSN1 had infested bate insect, which located in 7.5 cm depth of pine log. EPN has pathogenicity against larva and adult of JPS. Spray application of EPNs against adult of JPS, Heterorhabditis sp. Gyeongsan strain showed higher pathogenicity than S. carpocapsae GSN1 strain. EPN infested larva of JPS was detected on bark spray treatment with S. carpocapsae GSN1 strain in dead pine log that naturally infested larva of JPS however, no EPN infested JPS was detected on soaking of pine log with suspension of S. carpocapsae GSN1 strain. Though EPN had found with low efficacy against JPS but still possible to apply to control the boring insect pest as they can control log dwelling insect.

• Korean journal of applied entomology
• /
• v.46 no.1 s.145
• /
• pp.147-151
• /
• 2007

Laboratory tests were conducted to determine the susceptibility of the alfalfa weevil, Hypera postica to Korean entomopathogenic nematodes, Steinernema carpocapsae GSN1 strain (ScG), S. glaseri Dongrae strain (SgD), Heterorhabditis bacteriophora Hamyang strain (HbH), and Heterorhabditis sp. Gyeongsan strain (HeG) at the petri dish assay. The larval mortality of H. postica was significantly different depending on nematode species and treatment concentration. SgD and HeG strain were more effective against H. postica larva than ScG and HbH strain. When SgD and HeG strain were treated with the rate of >20 infective juveniles (ijs) per alfalfa weevil larva, mortality was ca. 77.5-100% at the late instars of H. postica in 3 days. The number of established nematode was significantly different depending on nematode species, whereas number of progeny was not significantly different. The mean number of established us of SgD strain in a host was the highest at 80 ijs by 30.2. The highest progeny number of HeG strain was 2,671.5 with 80 ijs. All nematode strains were not parasitic entirely to H. postica adults. These results show that alfalfa weevil late larva is highly susceptible to Korean entomopathogenic nematodes in the laboratory.

• Journal of agriculture & life science
• /
• v.45 no.6
• /
• pp.115-124
• /
• 2011

This study was conducted to find a useful alternative herbivore system with which to study the effects of ultraviolet exposure on the pathogenicity and survival of Korean isolated entomopathogenic nematodes (Heterorhabditis sp. 202 strain, Heterorhabditis sp. Gyeongsan strain, Steinernema sp. 223 strain, S. carpocapsae Pocheon strain, S. glaseri Dongrae strain and S. longicaudum Nonsan strain). Pathogenicity of entomopathogenic nematodes against silkworm, Bombyx mori, differed depending on the nematode species and strain and instar of silkworm challenged. Steinernematidae were relatively more pathogenic to the 5th instar silkworms, whereas Heterorhabditidae were more pathogenic to the 1st instars. UV-C exposure was harmful to entomopathogenic nematodes. All nematodes were killed within 60 minutes of exposure of UV-C, and after 10 min of exposure they caused only 6.7% corrected mortality of silkworms. Silkworms were not infected when they were fed S. carpocapsae Pocheon strain treated mulberry leaves which were exposed to UV intensity of about $2.3mW/cm^2$ for 4 hours in the field. Pathogenicity of S. carpocapsae was not significantly reduced after 1 hour of exposure to $4.0mW/cm^2$ UV intensity on the mulberry leaves against silkworms.