• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.250-254
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• 2007

Bacillus thringiensis strain 108 was isolated from soil and had nematicidal activity against second stage juvenile of plant root-knot nematode, Meloidogyne incognita. The strain 108, a rod shape, spore forming and Gram positive bacterium, produced lecithinase, catalase, and ${\delta}$-endotoxin. The strain 108 belongs to H serotype 3, Bacillus thuringiensis var. kurstaki. A nematicidal substance of the strain 108 was partially purified on Sephadex G-25 gel filtration, activated carbon adsorption, silica gel adsorption, and Sephadex G-10 gel filtration. $LC_{90}$ of the partially purified substance against M incognita was $1.2\;{\mu}g/ml$. The nematicidal substance was stable by heat treatment at $100^{\circ}C$ for 1hr, but was perfectly lost nematicidal activity after autoclave ($110^{\circ}C$, 30 min).

• Korean Journal of Organic Agriculture
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• v.30 no.3
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• pp.393-407
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• 2022

The effect of Neobacillus sp. JC05 extract on the defense response in cucumber plants against root-knot nematode (RKN) was evaluated. As a result of drench treatment of JC05-extract in cucumber plants, formation of egg mass per plants and disease severity were significantly decreased compared to untreated control plants; the malondialdehyde contents also decreased in JC05-extract treated plants. When eggs of Meloidogyne incognita were inoculated, cucumber plants treated with JC05-extract elevated pathogenesis-related gene expression such as chitinase and lipoxygenase, these are well known as inducing resistance in plants, in addition, peroxidase among antioxidant enzymes was significantly activated. Moreover, the JC05-extract enhanced FDAse activity in soils grown cucumber plants inoculated by eggs of M. incognita. Taken together, these results suggest that the JC05-extract could involve in activation of defense-related mechanisms of cucumber plants and result in decrease of disease occurrence caused by M. incognita.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.177-180
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• 2003

Pasteuria penetrans KW1 (PP), parasitic bacterium of nematode, was isolated from oriental melon greenhouse soil in Korea and evaluated for the suppression effect on the reproduction of southern root-knot nematode, Meloidogyne incognita (MI), in lettuce (Lactuca sativa L. var. Chungchima) and oriental melon (Cucumis melo L. var. Eunchun). Pot experiments were conducted by planting the lettuce seedlings in medium inoculated with 5,000 MI juveniles/pot (J), J +100,000 PP endospores/l g medium, and J +200,000 PP endospores/1 g medium. After 11 weeks of plantation, number of root galls in J +200,000 PP endospores/1 g medium was decreased to 92/root (38.9%, control effect), compared to the J of 150/root. In the second plantation of lettuce in the same pots, the numbers of root gall were significantly decreased in PP treated pots with 75 (77.2%, control effect) and 150/root (54.4%, control effect) in J +200,000 and J +100,000 PP endospores/1 g medium, respectively, compared to the J of 330/root when harvested at 10 weeks after planting. In oriental melon, root gall percentages were 32.1 (60.2%, control effect) and 52.9％ (34.5%, control effect) in J +200,000 and J + 1(10,000 endospores/l g medium which were significantly lower than that of 80.7％ in J.

• Research in Plant Disease
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• v.18 no.4
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• pp.370-375
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• 2012

Ninety two pepper (Capsicum annuum L.) cultivars were screened for resistance to two common species of root-knot nematodes, Meloidogyne incognita and M. arenaria. All 92 pepper cultivars were resistant to M. arenaria (0-3 eggmass/plant) but were susceptible to M. incognita (76-678 eggmass/plant). Susceptibility to M. incognita were slightly differed; 'Geomok' and 'Shintaepung' had relatively less eggmass (<100 eggmass/plant) when compared to those 29 very susceptible culivars such as 'Bulggotcheoreum' (>300 eggmass/plant). Therefore, pepper is highly recommended as a high-valued rotation crop to only those greenhouses infested with M. arenaria, but should restrict for M. incognita.

• Journal of Environmental Science International
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• v.27 no.12
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• pp.1241-1247
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• 2018

This study was conducted to evaluate resistance of 10 different cowpea cultivars which were introduced from the United States against two major root-knot nematodes, Meloidogyne arenaria and M. incognita, that affect greenhouse crop cultivation in Korea. The results showed that the resistance of the tested cultivars to the root-knot nematodes varied with the cultivar. Texas Cream 40 showed moderate resistance to M. arenaria whereas the other cultivars were susceptible. Purple Hull Pinkeye and Texas Pinkeye Purple Hull were found to be resistant to M. incognita, whereas Mississippi Silver showed moderate resistance and the other cultivars were susceptible. As the cultivars exhibit resistance to M. arenaria and M. incognita, such cultivars resistant to root-knot nematodes should be considered during the cultivation of cowpea as a green manure crop.

• 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.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.614-618
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• 2017

The root-knot nematode Meloidogyne incognita infects a variety of plants, including Arabidopsis thaliana. During migration, root-knot nematodes secrete different proteins to modify cell walls, which include pectolytic enzymes. However, the contribution of host cell wall proteins has not been described during this process. The function of two DUF642 cell wall proteins, BIIDXI (BDX, At4g32460) and TEEBE (TEB, At2g41800), in plant development could be related to the regulation of pectin methyl esterification status in the cell walls of different tissues. Accordingly, the expression of these two genes is up-regulated by auxin. BDX and TEB were highly induced during early M. incognita inoculation. Moreover, cell wall localization of the proteins was also induced. The cell wall localization of BDX and TEB DUF642 proteins during M. incognita early inoculation suggested that these two proteins could be involved in the regulation of the degree of pectin methylation during cell separation.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.288-298
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• 2014

We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN) Meloidogyne hapla in carrot (Daucus carota subsp. sativus) and tomato (Solanum lycopersicum). Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

• 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 Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.353-357
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• 2004

Large economic losses have been reported by root-knot nematide, Meloidogyne incognita, in Korea. However, fewy environmentally-friendly nematicide alternatives for the control of M. incognita have been developed. This study was conducted of Korean native plants to screen nematicidal activity which could be used by organic farmers. Methanol extracts (1,000 mg $L^{-1}$) from fifty-three Korean native plants were applied to 24-well tissue culture testplates containing $1\times10^2$ M incognita and the nematicidal activities were determined. Nematicidal activities of the methanol extracts in common purslain (Portulaca oleraceae L.) and water mouse-ear-chickweed (Stellaria aquatica Scop.) were 60.0% and 40.6%, respectively, compared with that of control, however, those of other forty-one plants were less than 30%. Our results suggest that the methanol extracts of common purslain and water mouse-ear-chickweed contain nematicidal active compounds.