• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.175-179
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• 2004

Trichoderma harzianum-THN1 parasitising the egg masses of root knot nematode Meloidogyne incognita was isolated from galled mulberry roots and evaluated for its potential to control root knot disease. In pot experiments root galling was reduced and leaf yield increased significantly following soil treatment with T. harzianum-THN1. The extracts obtained from the soils inoculated with T. harzianum-THN1 drastically inhibited the hatching of nematode eggs and the effect was irreversible even after the eggs were transferred to fresh water. The fungus was equally effective in controlling the disease in nematode infested mulberry garden under field conditions which was significant over the most commonly used egg parasitic fungus Paecilomyces lilacinus. The disease reduction recorded with T. harzianum was on par with the plants treated with the nematicide Carbofuran. The results suggest that T. harzianum- THN1 could be used as a potent ecofriendly biocontrol agent against M. incognita in mulberry without any residual toxicity to silkworms. T. harzianum- THN1 can form an important component of integrated disease management package in mulberry cultivation.

• Environmental Analysis Health and Toxicology
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• v.21 no.4 s.55
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• pp.323-330
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• 2006

The aim of current study was to evaluate the toxicity of nonylphenol(NP) on soil nematode, Caenorhabditi elegans. The stress-related gene expression, growth, reproduction and development have been employed to monitor soil toxicity. The 24-h median effect concentrations $(LC_{50s})$ of NP was $0.15mg/L$. The expressions of vitellogenin-6, vitellogenin-2, cytochrome P450 family protein 35a2 and apoptosis enhancer-1 genes were upregulated in C. elegans by NP exposure. Alterations in growth, reproduction and development were also observed in NP-exposed group and especially hatching failure was observed. The overall results indicate that C. elegans has considerable potential as sensitive markers for NP toxicity monitoring.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.101-106
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• 2013

To know how much damages occurred by nematodes in plastic vinyl house field, soil samples were collected from strawberry cultivation areas at Buyeo and Nonsan in Chungnam and Jinju in Kyeongnam, melon cultivation area at Gocksung in Junnam and cucumber field at Gongju in Chungnam. And then, nematode samples were separated from each soil sample, and identified the kind of plant-parasitic nematodes. Plant-parasitic nematodes were separated from 52 soil samples. Among samples, Meloidogyne spp., Pratylenchus spp. and Helicotylenchus spp. were isolated from 45 (86.5%%) and 33 (63.5%) and 47 collected soil samples (90.4%), respectively. As a result of identification of plant-parasitic nematodes from regional collected soil samples, distribution of Helicotylenchus spp. was higher than any other plant-parasitic nematode. And the population of Meloidogyne spp. and Pratylenchu spp. were also higher, and a occurrence ratio of Meloidogyne spp. is higher than Pratylenchu spp. except the cucumber growing area at Gongju.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.133-138
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• 2003

Five seed kernel namely, Neem (Azadirachta indica A. Juss.), Pongamia (Pongamia glabra L. Pierre), Tamarind (Tamarindus indica L.), Mahua (Madhuca indica Gmel.) and Shikakai (Acacia cancinna De.) were tested against hatching of eggs and larval mortality of Meloidogyne incognita causing root knot disease in mulberry along with Furadan (Carbofuran) and Bionema (a bioformulation developed from Verticillium chlamydosporium) for comparison. Results revealed that highest hush-up of hatching was observed in Neem (77.40%) and Pongamia (75.99%) seed kernel extracts at 100% concentration over the check. Similarly, highest larval mortality was observed in Neem and Pongamia by 76.00% and 74.50%, respectively at 100% concentration after 72 hrs of exposure period. Pot culture studies revealed that pre-application of seed kernel powders (20 days before inoculation of nematode) found to be more effective in controlling the root knot disease than post application. In pre application of seed kernel powders, maximum reduction of root knots was observed in case of Neem seed kernel powder (54.85%) followed by Pongamia (51.9%). Similar trend was also observed in reduction of egg masses/plant and nematode population ／250 cc soil. Rest of the seed kernel extracts was found to be less effective in suppression of hatching, enhancing the larval mortality and controlling the root knot disease. However, application of Furadan and Bionema tested for the comparison were found to be more effective than seed kernel powders. The generated information seems to be useful in developing an ecofriendly integrated approach for the control of root knot nematode disease in mulberry.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.359-359
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• 2017

A new soybean cyst nematode, H. sojae was reported from Korea in 2016. This species is closely related to H. glycines which has the same host plant. Morphological observations of the cyst, female, male and second-stage juveniles indicated that this species is differed from H. glycines. Especially, cysts of H. sojae appeared more round, shining and darker than that of H. glycines. The distribution of this new cyst nematode in soybean field in Korea is unknown so far. In 2016, 270 soil samples were collected from soybean fields and examined the existence of H. glycines and H. sojae. Total of 111 samples contained cysts (41.1%). Among them 77% were H. glycines and 23% were H. sojae. H. sojae is future threatening in soybean production area.

• Toxicological Research
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• v.26 no.4
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• pp.253-259
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• 2010

We are consistently being exposed to nanomaterials in direct and/or indirect route as they are used in almost all the sectors in our life. Nations across the worlds are now trying to put global regulation policy on nanomaterials. Sometimes, they are reported to be more toxic than the corresponding ion and micromaterials. Therefore, safety research of nanoparticles has huge implications on a national economics. In this study, we evaluated and analyzed the research trend of ecotoxicity of nanoparticles in soil environment. Test species include terrestrial plants, earthworms, and soil nematode. Soil enzyme activities were also discussed. We found that the results of nanotoxicity studies were affected by many factors such as physicochemical properties, size, dispersion method and test medium of nanoparticle, which should be considered when conducting toxicity researches. In particular, more researches on the effect of physicochemical properties and fate of nanoparticles on toxicity effect should be conducted consistently.

• Research in Plant Disease
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• v.7 no.1
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• pp.42-48
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• 2001

The effect of cultural, physical and chemical control methods on the population density of Meloidogyne arenaria second-stage juveniles (J2) and on fruit yields of oriental melon was investigated at Seongju Fruit Vegetable Experiments Station, Kyungpook province, Korea, for two years from 1999 to 2000. Crops used in a rotation prior to Oriental melon were rice, corn, sesame, and green onion. The physical methods used were either solarization, soil addition or soil drying, and a nematicide, fosthiazate of granular formula, was used as the chemical method, applying at a rate of 300g a. i./10 a. Growing rice in the rotation, solarization, and soil addition controlled the nematode disease most effectively, reducing the number of J2 by 90% and increasing fruit yields two times. However, the effects of these control methods on the J2 population were limited to the early growing season; the J2 population increased later, suggesting that additional control practices may be needed in the following season. The next effective control methods were use of corn in the rotation, the nematicide application, and soil drying. The nematicide application was effective only for the early fruit yield, but neither for the late nor for the total yields. Use of sesame or green onion in the rotation was not effective in controlling the nematode.

• Journal of Microbiology and Biotechnology
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• v.31 no.6
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• pp.815-822
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• 2021

Indigenous fungus-feeding nematodes may adversely affect the growth and activity of introduced biocontrol fungi. Alginate pellets of the biocontrol fungus Trichoderma harzianum ThzID1-M3 and sclerotia of the fungal plant pathogen Sclerotinia sclerotiorum were added to nonsterile soil at a soil water potential of -50 or -1,000 kPa. The biomass of ThzID1-M3, nematode populations, and extent of colonization of sclerotia by ThzID1-M3 were monitored over time. The presence of ThzID1-M3 increased the nematode population under both moisture regimes (p < 0.05), and fungivores comprised 69-75% of the nematode population. By day 5, the biomass of ThzID1-M3b and its colonization of sclerotia increased and were strongly correlated (R² = 0.98), followed by a rapid reduction, under both regimes. At -50 kPa (the wetter of the two environments), fungal biomass and colonization by ThzID1-M3 were less, in the period from 5 to 20 days, while fungivores were more abundant. These results indicate that ThzID1-M3 stimulated the population growth of fungivorous nematodes, which in turn, reduced the biocontrol ability of the fungus to mycoparasitize sclerotia. However, colonization incidence reached 100% by day 5 and remained so for the experimental period under both regimes, although hyphal fragments disappeared by day 20. Our results suggest that indigenous fungivores are an important constraint for the biocontrol activity of introduced fungi, and sclerotia can provide spatial refuge for biocontrol fungi from the feeding activity of fungivorous nematodes.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.413-420
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• 2017

Sugarbeet cyst nematode (Heterodera schachtii) has recently been detected as a severe pest of Chinese cabbage fields in Korea. Two studies were performed to evaluate the effect of inoculation density of H. schachtii and plant age of Chinese cabbage on the final population of the nematodes. Chinese cabbage inoculated with high inoculation density (4 juveniles or eggs/g soil) showed significant differences in the number of cysts, females and eggs. The 40 day- old plants inoculated with high nematode densities yielded the highest nematode populations after 30 and 60 days of inoculation, compared with other plant age groups (0, 20, 30 day-old)used in the experiment. We, thus, summarize that, maximum nematode multiplication rates are made on comparatively older plants at the high nematode densities. Therefore, taking plant age into consideration at the transplanting of Chinese cabbage was recommended for the management of H. schachtii.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.27-31
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• 2003

This study has been conducted to assess and analyze the damage of Codonopsis lanceolata by differential inoculation levels of Meloidogyne hapla in pot and plot. As the density of M. hapla increased, early growth of C. lanceolata was inhibited 60% in vine and 54% in root. However, growth of C. lanceolata was not remarkably different by density of M. hapla in the plot test. This result may be attribute to low density of M. hapla in the plot.