• The Plant Pathology Journal
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• 제34권3호
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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.

• 식물병연구
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• 제7권1호
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• pp.49-55
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• 2001

남부 시설재배지에서 서식하는 뿌리혹선충의 종류와 race를 조사하고 그들에 대한 간이동정법을 제시하였다. 남부 시설재배지에는 Meloidogyne arenaria race 2(59%), M. incognita race 1(23%), M. incognita 미동정 race(18%)가 분포하고 있었음, 우점종은 땅콩뿌리혹선충(M. arenaria) race 2 였다. 유충의 길이는 M. arenaria가 411$\mu\textrm{m}$(306-503$\mu\textrm{m}$), M. incognitark 384$\mu\textrm{m}$(312-488$\mu\textrm{m}$)로 두 종의 범위가 겹치고 있어 종 동정에 참고하기 어려웠으며, M. arenaria와 M. incognita의 종 동정에 가장 쉽게 이용할수 있는 특징은 암컷의 머리에 있는 Excretory pore 위치였다.

• 식물병연구
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• 제16권1호
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• pp.10-20
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• 2010

Root-knot nematodes cause billions of dollars in crop losses annually have a broad range of host over 2,000 species of plants. These nematodes are known as obligate, sedentary endo-parasites in a plant host to feed upon to complete their life cycle. To prevent the plant parasitic nematode, methyl bromide was widely applied as a soil fumigant. Other strategies to prevent or control nematodes involve RNAi-mediated suppression, R gene transformation, natural products or chemical treatments, the expression of peptide or proteins in susceptible plants, and others. Over the last decade, the entry in GenBank for Meloidogyne reveals 73,340 ESTs and recently two complete Meloidogyne spp. genomes sequences have simultaneously been presented by two groups. Recent works have demonstrated the effect of RNAi suppression to nematode target genes. These results will provide novel members of genes as a foundation for studies focused on understanding the function of M. incognita nematode genes as well as for the development of novel target genes for parasite control. Thus the successful development of biotechnology-derived plants with nematode resistance will result in large yield benefits for producers as well as environmental benefits and will accelerate the research related to pathogensresistant crops.

• 식물병연구
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• 제19권1호
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• pp.25-30
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• 2013

국내에서 시판되고 있는 토마토 36품종을 이용하여 국내 시설재배지에서 가장 많이 분포하고 있는 두 종의 뿌리혹선충, Meloidogyne arenaria와 M. incognita에 대한 저항성을 검정하였다. 방울토마토 중에서는 '텐텐', '캐딜락', '큐티', '스위트', '뽀또', '리코핀-9' 등 6품종, 완숙토마토 중에서 '러브리240', '도테랑다이아', '큐피랑', '도테랑마스터', '슈퍼도태랑', '도태랑시즌', '마이로꾸', '호용' 등 8품종, 대목은 '스페셜', '파이팅', '마그네트' 등 3품종이 두 종류의 뿌리혹선충에 모두 강한 저항성이었다.

• 한국식물병리학회지
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• 제14권6호
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• pp.603-605
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• 1998

Soil and root samples were collected form the rhizoshpere of 11 different medicinal plants to determine the incidence, density and identification of root-knot nematode species associated with medicinal herbs. About 55% of medicinal herbs examined was found to be infested with root-knot nematodes. As a result of infection casued by three root-knot nematodes, M. hapla recorded 43.3% in medicinal herba whereas M. incognita and M. arenaria showed 7.9% and 3.7%, repectively. Forsythia koreana, Hemerocalis fulva, Hibuscus mutabilis and Petasites japonicus were the most severely infested herbs whereas Acanthopanax sessilflorus was least infested. Population of the second stage younger plants. Meloidogyne hapla, M. incognita and M. arenaria were the species associated with the medicinal herbs. The most abundant nematode observed in medicinal herbs was M. hapla and followed by M. incognita and M. arenaria. M. arenaria was observed firstly on Ficus carica, one of medicinal plant.

• 한국잠사곤충학회지
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• 제40권2호
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• pp.117-125
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• 1998

Entomopathogenic nematodes, Heterorhabditidae and Steinernematidae, were isolated from the soil of mulberry field, and the high infectivity and invesiveness were confirmed in the silkworm, Bombyx mori. The cause of non-microbial and acute flacherie was found as an disease by infection with soil-born nematodes through the mulberry leaves contaminated with soil and rainwater. The causal nematodes were isolated by silkworm trap from all of the 5 soil samples collected on the 5 mulberry fields, and identified as 3 strains of Heterorhabditis sp. and 2 of Steinernema sp. Rainwater itself, however, wasn't engaged in the silkworm disease, mulberry leaves with rainwater was rather profitable for cocoon production when the leaf quality was too hard to feed silkworm. Feeding of wet mulberry leaves with rain might not so harm to silkworm when the condition of rearing room to be kept at suitable temperature and ventilated well. Nematode infection of silkworm could be occurred by harvesting and feeding of contaminated mulberry leaves on the weather condition of rainy and wind. For the prevention of nematode infection, silkworms should be fed the leaves harvested from the higher portion of the mulberry tree in rainy days. For an oppositional application of this susceptibility of silkworms to nematode, might be useful on the collection and amplification of nematode agents for biotic control of pest insects.

• 한국응용곤충학회지
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• 제22권1호
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• pp.15-20
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• 1983

당근혹선충의 피해 정도와 경제적 피해 수준을 결정하고자 폿트 시험으로 실시한 결과 선충 접종 8주후까지는 고추, 토마토 모두 생육에 차이가 없었으나 12주 이후 주당 10,000마리 이상 접종구에서는 현저하게 떨어졌고 저밀도 접종일 때 생장 촉진 효과는 작물에 따라 차이가 있었다. 선충 접종 밀도와 고추, 토마토 수량과의 관계는 주당 7,500마리 이하 접종에서는 무처리와 차이가 없었으나 10,000마리 이상에서는 고추 $15\%$, 토마토 $14\%$ 이상 감수되었다.

• Ocean and Polar Research
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• 제42권1호
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• pp.1-13
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• 2020

We analyzed the characteristics of meiofaunal communities in the northern part of Jeju Island and the environmental factors affecting the meiofaunal communities. For the analysis of the communities, subtidal sediments containing meiofauna were collected from 6 sites (3 shallow sites and 3 deeper sites) on the northern coast of Jeju Island in April, June, August, and October 2017. The sediment samples were collected by SCUBA using a syringe. After isolating and counting meiofauna from the sediment using a series of sieves and centrifugation, the density of the meiofauna was expressed as individuals/10 ㎠. Density of meiofauna was lower in August compared to April and June, and the density determined in October was higher than August. During April and June, the meiofaunal communities at the shallow sites (i.e., ST 1, 2, and 3) were significantly different from the meiofaunal communities at deeper sites (ST 4, 5, and 6, p < 0.01). However, such spatial variation in the meiofaunal communities was not obvious in August and October. The most dominant meiofaunal taxa were harpacticoids, followed by nematodes and nauplius larvae. These three taxa accounted for 90% of the total meiofauna density. Abundance of harpacticoids and nematodes showed a significantly negative correlation with the water depth. BIO-ENV analysis indicated that the total organic nitrogen (TON) and the water temperature exerted a significant influence over the meiofaunal communities at the sampling sites.

• 한국미생물·생명공학회지
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• 제38권2호
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• pp.117-123
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• 2010

BT toxin is produced by a soil bacterium Bacillus thuringiensis and has long been used as a biological insecticide without any competition. Recently, Photorhabdus, a symbiotic bacterium from entomopathogenic nematodes, family Heterorhabditae, has been researched and discussed as alternatives to B. thuringiensis. Photorhabdus, which lives in the gut of entomopathogenic nematodes, is a highly virulent pathogen of a wide range of insect larvae. When an insect is infected by the nematodes, the bacteria are released into the cadaver, and produce a number of insecticidal toxins. The biological role of the different Photorhabdus toxins in the infection process is still unclear. Photorhabdus toxin complex (Tc) is highly secreted gut-active toxin and has been characterized as a potent three-component (A, B and C) insecticidal protein complex. These components are necessary for full oral activity against insect larvae. The Photorhabdus PirAB binary toxins exhibit a potent injectable activity for Galleria mellonella larvae, and have oral toxicity against mosquitoes and caterpillar pest Plutella xylostella. Other toxin, 'makes caterpillars floppy' (Mcf) showed injectable activity on caterpillars. Recombinant Mcf triggers apoptosis in both insect hemocytes and the midgut epithelium and carries a BH3 domain. In this review, the relationship between the Photorhabdus and the nematode is discussed and recent important insecticidal toxins from Photorhabdus are described.

• The Plant Pathology Journal
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• 제38권4호
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• pp.261-271
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• 2022

Root-knot nematodes are the most important plant-parasitic nematodes worldwide. Many efforts have been made to find non-chemical, risk-free, and environmentally friendly methods for nematode control. In this study, the effects of compost and vermicompost of arugula (Eruca sativa) on Meloidogyne javanica were investigated in three glasshouse experiments. In addition, the expression of the defense-related genes nonexpressor of pathogenesis-related 1 (NPR1) and lipoxygenase 1 (LOX1) was detected in tomato plants treated with vermicompost of arugula at 0, 2, 7, and 14 days after nematode inoculation. The result showed that the vermicompost of arugula significantly reduced the reproduction factor of the nematode by 54.4% to 70.5% in the three experiments and increased the dry weight of shoots of infected tomato plants. Gene expression analysis showed that LOX1 expression increased on the second and seventh day after nematode inoculation, while NPR1 expression decreased. The vermicompost of arugula showed stronger nematode inhibitory potential than the vermicompost of animal manure. The vermicompost of arugula is superior to arugula compost in suppressing the activity of M. javaniva and reducing its impact. It manipulates the expression of resistance genes and could induce systemic resistance against root-knot nematodes.