• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.1-6
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• 2002

To elucidate the effect of soil addition and subsoil plowing on the change of sell chemical properties and the reduction of root-knot nematode, this experiment carried out in continuous cropping field of protected oriental melon (Cucumis melo L.). Soil addition reduced electric conductivity (E. C.) from 4.3 to 1.8 dS/m (58%), available $P_2O_5$ from 406 to 182 mg/kg (55%) and organic matter content from 16 to 11 g/kg (31%). Population densities of root-knot nematode in soil reduced as much as 89%, 84%, and 69% at first year, third years, and of five years later, respectively The effects of subsoil plowing were similar to that of soil addition. E. C. and phosphate were reduced from 4.30 to 1.98 dS/m (54%) and phosphate from 406 to 329 mg/kg (19%), respectively. Population densities of root-knot nematode reduced as much as 71%, 67%, and 42% after 1, 3, and 5 years, respectively Subsoil plowing reduced nematode densities only for three years.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.241-249
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• 2018

Commercial biocontrol of microbial plant diseases and plant pests, such as nematodes, requires field-effective formulations. The isolate Pseudomonas chlororaphis O6 is a Gram-negative bacterium that controls microbial plant pathogens both directly and indirectly. This bacterium also has nematocidal activity. In this study, we report on the efficacy of a wettable powder-type formulation of P. chlororaphis O6. Culturable bacteria in the formulated product were retained at above $1{\times}10^8$ colony forming units/g after storage of the powder at $25^{\circ}C$ for six months. Foliar application of the diluted formulated product controlled leaf blight and gray mold in tomato. The product also displayed preventative and curative controls for root-knot nematode (Meloidogyne spp.) in tomato. Under laboratory conditions and for commercially grown melon, the control was at levels comparable to that of a standard commercial chemical nematicide. The results indicated that the wettable powder formulation product of P. chlororaphis O6 can be used for control of plant microbial pathogens and root-knot nematodes.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.66-74
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• 2017

This study was conducted to examine infectivity (penetration and gall and egg-mass formations) of the root-knot nematodes, Meloidogyne incognita and M. hapla, on carrots grown in soil conditions of 5 different soil textures consisting of bed-soil (b) and sand (s) mixtures (b-s mixtures) at the ratios of 10:0, 7:3, 5:5, 3:7, and 0:10. For M. incognita, the nematode penetration rates in b-s of 0:10 (100% sand) were significantly higher than in the other b-s mixtures, more greatly at 2 and 5 days after inoculation than at 10 DAI, while no significant differences in the penetration rates were mostly shown for M. hapla at the above DAI. However, for both nematodes, gall and egg-mass formations were remarkably increased in the b-s mixture of 0:10, compared to the other b-s mixtures, which is coincided with the general aspects of severe nematode infestations in sandy soils. This suggests the increased gall and egg-mass formations of M. incognita should be derived from the increased penetration rates in the sandy soil conditions, which provide a sufficient aeration due to coarse soil nature for the nematodes, leading to their mobility increased for the enhanced root penetration. For M. hapla, it is suggested that the sandy soil conditions affect positively on the healthy plant growth with little accumulation of the inhibitory materials and sufficient aeration, enhancing the nematode growth and feeding activities. All of these aspects provide information reliable for the development screening techniques efficient for the evaluation of the nematode resistance in the breeding programs.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.114-117
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• 2012

The biological control efficacy of a greenhouse soil bacterial mixture of Lactobacillus farraginis, Bacillus cereus, and Bacillus thuringiensis strains with antinematode activity was evaluated against the root-knot nematode Meloidogyne incognita. Two control groups planted in soil drenched with sterile distilled water or treated with the broad-spectrum carbamate pesticide carbofuran were used for comparison. The results suggest that the bacterial mixture is effective as a biocontrol agent against the root-knot nematode.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.255-258
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• 2011

When kiwifruit root system infected with nematodes was treated by hot water dipping treatment, the maximum temperature for this treatment was suggested as $50^{\circ}C$. The lowest killing temperature of internal root-knot in the root tissue was $48^{\circ}C$. Consequently, root-knot nematodes could be killed without damaging root tissues by the hot water dipping treatment at $48^{\circ}C$ for 10 minutes. This could be useful for organic production and distribution of kiwifruit seedlings by avoiding the synthetic nematicides which are not easily decomposed in soil once applied.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.75-81
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• 1995

To reduce crop damage from root-knot nematode, Meloidogyne spp. chemical, cultural, physical control methods were compared in commercial greenhouse for 3 years from 1992 to 1994. Timing of sol exchange for economic losses due to the nematodes is important: every 3 years for coarse sand (Masatto) and every 4 years for red-yellow soil. Control effects on Meloidogyne spp. in cucumber were 78.2% in Dazomet DP, 72.1% Carbo G+Soil reverse+submergence, and 66.3% in Carbo G+submergence. Pesticide effects were temporally different after treatment: 77.7~80.6% in 20 days and 33.7~49.5% in 60 days. Cropping system in oriental melon gave an excellent control effect of 81.1% at oriental melon/rice culture. All methods controled root-knot nematodes at the time of the treatment but the number of the nematodes increased at the end of the season. However, soil exchange was effective for 3 years. The most economic control practice is rotation with rice for every three years.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.79-85
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• 2006

This study was conducted to get basic information on the occurrence of plant-parasitic nematodes for the establishment of nematode management strategy in major potato production areas in Korea. Nationwide soil collection was done in 11 areas of Cheju, Yesan, Gimchun, Goryoung, Hong chun, Pyungchang, Gimjae, Milyang, Namwon, Gangnung, and Inje in 2004-2005. Root-hot nematode juveniles(J2) were detected in 30 samples among the 50 samples. The average density was 12-69 J2/100cc soil. Pratylenchus sp., Helicotylenchus sp., Ditylenchus sp., Tylenchus sp., and Tylenchorhynchus sp. were also detected in various locations, however, their densities were very low. Root-knot nematode females were collected from tomato roots inoculated with the potato field soils for PCR-RFLP identification. The females from Cheju, Milyang, and Goryung showed PCR products of 500 bp. And the Dra I restriction enzyme digestions showing 290 bp and 230 bp fragments confirmed their identity as Meloidogyne hapla.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.105-111
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• 2013

The experiments were carried out to investigate the biocontrol potential of Lysobacter capsici YS1215 on root-knot nematode and to characterize its lytic enzyme activities. L. capsici YS1215 showed chitinase and gelatinase activities on the medium containing 0.5% chitin or 0.5% gelatin as substrates. Cell growth of L. capsici YS1215 was highest at 6 days, and the highest activities of chitinase (4.0 unit $ml^{-1}$) and gelatinase (7.43 unit $ml^{-1}$) were observed on 3 and 5 days after incubation, respectively. To investigate the effect of L. capsici YS1215 on tomato growth and nematode infection, the plants in pot trial were treated with bacterial culture (BC), half of bacterial culture (HBC), only bacterial medium (BM), tap water (TW) and commercial nematicide (CN). HBC treatd plants showed the higher shoot fresh weight and dry weight on $5^{th}$week after incubation while BM, HBC and BC had consistently higher values than TW at $9^{th}$ week. HBC appeared to be the highest shoot fresh length at $9^{th}$ week. Both CN and BC showed lower number of egg mass, root gall, and population of juveniles in soil compared to BC, HBC, BM and TW. These results suggest that L. capsici YS1215 with its strong ability of lytic enzyme production can be one of the most significant candidates for biocontrol agents against root-knot nematodes.

• Journal of Plant Biotechnology
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• v.50
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• pp.163-168
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• 2023

Sweetpotato (Ipomoea batatas [L.]) is a globally important root crop cultivated for food and industrial processes. The crop is susceptible to the root-knot nematode (RKN) Meloidogyne incognita, a major plant-parasitic RKN that reduces the yield and quality of sweetpotato. Previous transcriptomic and proteomic analyses identified several genes that displayed differential expression patterns in susceptible and resistant cultivars in response to M. incognita infection. Among these, several sporamin genes were identified for RKN resilience. Sporamin is a storage protein primarily found in sweetpotato and morning glory (Ipomoea nil). In this study, transcriptional analysis was employed to investigate the role of sporamin genes in the defense response of sweetpotato against RKN infection in three susceptible and three resistant cultivars. Twenty-three sporamin genes were identified in sweetpotato and classified as group A or group B sporamin genes based on comparisons with characterized sweetpotato and Japanese morning glory sporamins. Two group A sporamin genes showed significantly elevated levels of expression in resistant but not in susceptible cultivars. These results suggest that the elevated expression of specific sporamin genes may play a crucial role in protecting sweetpotato roots from RKN infection.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.223-227
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• 1981

These experiments were conducted to investigate the nematicidal effects of the insecticides, Mocap(O-Ethyl-S, S-dipropyl phosphorodithioate), Carbofuran(2,3-Dihydro-2,2-dimethyl benzofuranyl ethyl carbamate), Terbufos (S-tert-buthylthio methyl O,O-diethyl phosphordithioate) and their mixtures (Mocap+carbofuran, Mocap+Terbufos, Carbofuran+Terbufos) on growth of 2year-old ginseng, Panax ginseng C.A. Meyer, and the control of root-knot nematodes. There was no evidence of plant injury from insecticide treatment of ginseng, although the rate of emergence of the treated ginseng was slightly inhibited. The insecticide treatments showed no of-flavor of ginseng plant. Terbufos and Mocap provided heifer confrol of the root-knot nematodes than carbofuran alone and their mixtures. Mixtures of the insecticides showed antagonisitic effect to the root-knot nematodes.