• 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.

• Korean journal of applied entomology
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• v.21 no.1 s.50
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• pp.34-37
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• 1982

Two species of root-knot nematode, Meloidogyne incognita and M. hapla, were used in tests of soybean cultivars for resistance. Sixteen soybean cultivars were planted in the 20-cm clay pot and inoculated with each of M. incognita and M. hapla. Four soybean cultivars, Eundaedu, Baegcheon, Dongbugtae and Danyeobkong were resistant; Kwangdu, Hwanggeumkong, and Buseog were moderate, and the rest nine cultivars were susceptible to M. incognita. Jangyeobkong only was resistant, Danyeobkong, Hill, Dongbutae, Hamandaerip and Chungbugbaeg were moderate, and the rest ten cultivars were susceptible to M. hapla. There were no cultivars resistant to both nematodes although Dongbugtae and Danyeobkong were resistant to M. incognita and moderately resistant to M. hapla.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.164-167
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• 1987

The effects of infection severity of susceptible tomato varieties, Rutgers and Boksu 2, by root-knot nematode, meloidogyne hapla, M. arenaria or M. javanica on plant growths and tomato yields were investigated. The inoculum levels of each nematode species were 0, 1,000 and 10,000 nematodes per 42cm diam. pot. Tomato yield was reduced by the nematode infection. Severity of infection was on the decreasing order of M. javanica, M. incognita, M. arenaria, M. hapla, ranging from $80\%$ by M. javanica to only $7\%$ by M. hapla. Yield reduction by infection of M. hapla was more prominent in Boksu 2 than in Rutgers. However the results were vice versa for the other nematode species, The top fresh-weight of Rutgers inoculated with 10,000 nematodes was greater than root weight, regardless of the nematode species, whereas plant height and top fresh weight decreased with increasing root weight when inoculated with inoculum density of 1,000/pot.

• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.32-39
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• 1999

The following is experimental result of selecting soil bacteria showing toxicity against Root-knot nematode (Meloidogyne hapla). Out of 286 strains isolated from soil, one(NC67) showing toxicity against M.hapla is selected The selected strain(NC67) is identified of B. thuringiensis subsp. indiana. It proved out that the toxic maerial against M. hapla produce by NC67 strain is an exotoxin. The result of examining the existence of the extercellular toxicity product by the toxic strain(NC67) by usign activated carbon column chromatography, Dowex 50W column chromatography and TLC of silical gel etc. proved out that it is a single material.

• Journal of Ginseng Research
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• v.20 no.3
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• pp.331-338
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• 1996

This study was conducted to screen the antagonistic plants on northern root-knot nematode (Meloidogyne) and to utilize those in its control. Egg hatching of M. hapla was found to be inhibited by 17 plant methanol extracts, and 11 plant extracts among them were also toxic to M. hapla second stage juvenile. Egg hatching of iW. hapla was also found to be inhibited by squeezed extracts of Cassia tora and Zea mays, and they were also toxic to M. hapla second stage juvenile. Extracts of Achyranthes japonica, Melia axedrach and Acorus graminens were toxic to M. hapla second stage with a juvenile mortality above 70clc at the 10 folds diluted concent ration and A. graminens was toxic to tested juvenile mortality above 50% at the 100 folds diluted concentration. The toxicity was directly propotional to the diluted concentration of the plant extracts and to the exposure period. Punica granatum, Acorns graminens and Melia axedrach were effective in inhibiting root penetration of JW. hapla juveniles, among of them p. granatum is most effective Percent inhibition of penetration by second and third stage juveniles into tomato slants penetrating by it was 72.7 and 82.4%, respectively.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.339-346
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• 2006

Total 90 species of medicinal plants were surveyed to see if they have any suppressive effects on the dinsity of M hapla at the exhibition field in the Chinan medicinal herbs experiment station. In 70 species including Achyranthes japonica, root-knot and/or egg sac of M. hapla was not found and these plants were planted in C. lanceolata field to check the degree of M. hapla infection. In 26 species including A. japonica, M. hapla infection was not observed. Simultaneously, 30 species were planted in pots to find out degree of infection by M. hapla. Dianthus chinensis, Rudbeckia bicolor, Sedum kantschaticum, Ricinus communis, Anemarrhena asphodeloides, Malva verticillate, Chelidonium majus, Sesamum indicum, Agrimonia pilosa, Geum aleppicum, Sanguisorba officinalis and Scrophularia buergeriana were free from infection. While the number of galls and density of M. hapla in soil were higher to high innoculation density, and the growth of C. lanceolata was rower.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.1
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• pp.39-45
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• 1979

Egg masses of the root- knot nematodes ( Meloidogyne incognita, M. arenaria and M. haply) were exposed to two different regimes of soil moisture (459 and 2459) and temperature ( -2$^{\circ}C$ and 33$^{\circ}C$), quite extreme condition in their natural environment, and their survival rate was compared. Three species did not show any difference in the rate when exposed to either soil moisture for 25 days, with the rate in the range of 8.6% to 10.4%. In response to temperature treatment, however, they differed : the best survival rate was obtained from M. incognita at high temperature ( 33"C) and from M, hapla at low temperature (-2$^{\circ}C$) plot. The third species (M. arenaria) was intermediate in both temperature regimes.imes.

• Korean journal of applied entomology
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• v.41 no.3
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• pp.225-231
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• 2002

The entomopathogenic nematodes, Steinernema carpocapsae All strain (ScA), S.glaseri NC strain (SgN) and H. bacteriophora NC 1 strain (HbN), were evaluated for the effects on egg mass formation by the northern root-knot nematode, Meloidogyne hapla in pot experiment using tomato. In the first experiment, 2.5$\times$10$^{5}$ infective juveniles (Ijs) of entomopathogenic nematodes were inoculated to 100 g of the soil infected with ca. 450 Ijs of M. hapla/100 ㎤ in 150 $mell$ container. The number of egg mass was significantly decreased to 9.4-36.5 in ScA, to 5.7-24.7 in SgN and to 11.2-16.0 in HbN treatments compared with 62.5 in M.hapla alone. In the second experiment, ScA and S.carpocapsae Pocheon strain (ScP) and SgN and S.glaseri Dongrae strain (SgD) were treated to 350 g of the soil infected with 100, 200 M.hapla larvae/100 ㎤ in 450 $mell$ container The entomopathogenic nematodes were inoculated at the rate of 2,020 Ijs and 1.6$\times$105 Ijs in 350 g soil. The number of egg mass of M.hapla were significantly decreased in the entomopathogenic nematode treatments compared with M.hapla alone although no differences were observed among Steinernema species, strains, or infection concentrations. Treatments of entomopathogenic nematodes 3 days before M.hapla inoculation were more effective on reduction of egg mass formation than those of 3 days after M.hapla treatments. Growth of tomato was not affected by entomopathogenic nematode treatments.

• The Plant Pathology Journal
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• v.31 no.4
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• pp.441-445
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• 2015

Carrot (Dacus carota var. sativus) is one of the top-ten most economically important vegetable crops produced worldwide, and the root-knot nematodes, Meloidogyne spp., are one of the most important pests in the carrot. In Korea, M. hapla and M. incognita are presumed to be the major root-knot nematodes distributing mostly in open carrot fields and greenhouses, respectively. In our study, currently-developed and commercial carrot cultivars and the parental lines were examined for their pathological responses to M. incognita and M. hapla 7 weeks after inoculation with about 1,000 second-stage juveniles (J2) of the nematodes. All the carrot cultivars and lines showed susceptible responses to both nematodes with the gall index (GI) of 2.4-4.4, which were always higher on the carrot plants infected with M. incognita than M. hapla. Gall sizes were remarkably larger with more serious reduction of the root growths in the plants infected with M. incognita than M. hapla, suggesting the carrot lines examined in our study were more susceptible to the former than the latter. In the infection sites of the root tissues, giant cells were more extensively formed, occupying larger stellar regions with the prominent destruction of adjacent xylem vessels by M. incognita than M. hapla. All of these results suggest M. incognita affect more seriously on the carrot plants that are grown in greenhouses, compared to M. hapla that has a major distribution in open carrot fields, which would be used for determining cropping systems based on target nematode species, their damage and pathological characteristics.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.27-34
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• 2004

This study was conducted to develop optimal control tactics of the northern root-knot nematode, Meloidogyne hapla, using cultural method and biological agents ｛Bacillus thuringiensis (Bt), Paecilomyces lilacinus and plant extract (Huhjunl)｝ in the fields of Codonopsis lanceolata. Germination of C. lanceolata was susceptible to fosthiazate, but not to Bt or a plant extract. In pot assay, the inhibitory effect of two microbial agents, Bt and Paecilomyces lilacinus, on M. hapla were significant, but less than that of fosthiazate. The plant extract also had significantly inhibitory effect on M. hapla. In field assay, treatments of P lilacinus and fosthiazate resulted in maximal yields and qualities of C. lanceolata. The effect of the plant extract on the yields of C. lanceolata was also better than no treatment. The nematode-occurring condition of the fields before transplanting had significant effect on development of C. lanceolata; nematode-occurring field type gave less yields than nematode-free field type. These results suggest that a cultural control technique using paddy field, microbial pesticides using Bt or P lilacinus, and the plant extract are the promising control tactics against M. hapla in C. lanceolata fields. As a field manual to decrease economical damage of C. lanceolata due to M. hapla, this study suggests that C. lanceolata can be cultured directly in paddy field or in upland field after nematode control using microbial agents or the plant extract.