• 한국유기농업학회지
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• 제27권4호
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• pp.501-512
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• 2019

To survey the incidence of plant-parasitic nematodes, 187 soil samples from leguminous plant fields in Chungnam province, Korea were assessed from June to August 2018. As the result, four nematode genera - the cyst nematode (Heterodera spp.), root-knot nematode (Meloidogyne spp.), root-lesion nematode (Pratylenchus spp.), spiral nematode (Helicotylenchus spp.) - were detected. Among them, the incidence of cyst nematode was the highest in Taean (73%) and lowest in Hongseong (10%). The cyst nematode was detected from the adzuki and kidney bean fields as well as soybean fields. The incidence of cyst nematode in upland fields was higher than in paddy fields. In addition, the extracted cyst nematodes consisted of two species, which was identified as Heterodera glycines and H. sojae. The incidence of H. glycines (22%) was higher than H. sojae (10%), and a few of the fields (5%) was mixed with two cyst nematodes. This result suggested that we should consider that the cyst nematode is the major plantparasitic nematode when controlling the nematodes in soybean fields in Chungnam province.

• 한국식물병리학회지
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• 제14권5호
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• pp.386-392
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• 1998

Reproduction of the soybean cyst nematode (SCN), Heterodera glycines Ichinohe on the susceptible soybean cultivar, Lee 74, was significantly reduced by pre-, post- and simultaneous treatments of acetylsalicylic acid (ASA, aspirin). The control efficiencies were 60%, 64% and 87% for pre-, post- and simultaneous treatments, respectively. ASA had no significant effect on the survival of 2nd stage juveniles and their penetration into the soybean root tissues, but significantly inhibited the early stage nematode growth in the roots. Syncytia were formed 2∼3 days after inoculation in the susceptible soybean without ASA treatment, characterized by dense cytoplasm and increased cellular organelles such as mitochondria and endoplasmic reticulum. The nematode stylet was penetrated into the syncytial cell, and feeding tube was formed at the nematode stylet was penetrated into the syncytial cell, and feeding tube was formed at the nematode stylet entry. However, in the ASA treatments, syncytium was not formed or degenerated, depending on the root tissues. In the pre-treatments of ASA, nematode stylets did not penetrate into cells, showing callose-like cell wall thickening formed at the nematode probing sites, or retracted from the infected cells. The stylet penetration sites of syncytial cells appeared to be sealed off with fibrillar materials. With post-treatment of ASA, syncytia formed by the nematode were degenerated, characterized by degradation of syncytial cytoplasm.

• 한국수산과학회지
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• 제48권5호
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• pp.731-738
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• 2015

Nematode infection in the epithelial tissue of cultured rockfish Sebastes schlegeli was first reported in 2012. Since then, nematode infections have caused serious economic losses in rockfish aquaculture on the west coast of Korea. Taxonomic and life cycle information for this parasite are currently unknown. In this study, 18S rRNA and cytochrome c oxidase subunit I (COI) genes were used for molecular identification and polymerase chain reaction (PCR) to detect the invisible stages of this parasite. Nucleotide sequences of the 18S rRNA of the rockfish nematode showed 98% identity with that of Philometra morii. Therefore, this rockfish nematode was classified to the Philometridae family. However, we could not identify it to genus level using 18S rRNA. Its COI nucleotide sequences shared 85% and 82% identities with those of Bursaphelenchus sinensis and Philometra overstreeti, respectively. In addition, two gene-specific primer sets were designed based on the 18S rRNA gene to detect the intermediate host and nematode larvae. These primers were specific to this rockfish nematode without cross-reacting to other pathogens. The detection limit of the PCR assay using these primers was 1,000 copies of nematoda plasmid DNA. Therefore, the PCR assay described here is suitable for the detection of nematode DNA within rockfish. In addition, this PCR assay could be used to detect nematode larvae and the intermediate host.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권2호
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• pp.101-106
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• 2007

During mulberry cultivation, root disease complex caused by the association of root knot nematode (Meloidogyne incognita) with root rot pathogens like Fusarium solani and Botryodiplodia theobromae poses serious loss in leaf production. Therefore, an attempt was made to assess the efficacy of eight pesticides (Metayalaxyl+Mancozeb, Thiophanate methyl, Mancozeb, Bitertanol, Phenomiphos, Phorate, Thionazin & Carbofuran) and two growth hormones (Salicylic acid and Indole 3 acetic acid) at 0.1 and 0.2% concentrations under in vitro conditions against nematode (hatching of eggs and mortality of larvae) and root rot pathogens (poisoned food technique) for short listing the treatments to develop an IDM strategy. Results revealed that among the pesticides and growth hormones, Carbofuran followed by Salicylic acid were found to be effective at 0.2% concentration against both nematode and pathogenic fungi. Both the chemicals inhibited the hatching of nematode eggs by 83.5-78.9% and 80-76% larval mortality over the control and reduced the mycelial growth of both the pathogenic fungi to an extent of 75.5-77.8%. Though Mancozeb inhibited both the pathogenic fungi strongly (77-80%), it did not show any effectiveness against nematode. The rest of the chemicals were found either moderately or poorly effective in reducing the growth of pathogenic fungi, hatching of nematode eggs and enhancing the mortality of larvae. The two effective chemicals viz., Carbofuran and Salicylic acid, which rated as strong inhibitors against both nematode and pathogenic fungi, can be exploited in developing an IDM package as one of the component for better management of root disease complex in mulberry.

• 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.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.679-684
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• 1994

For a biological control of root-knot nematode (Meloidogyne incognita) in tomato, efficiency of Bacillus thuringiensis subsp. indiana strain TH109 (BtTH109) on the nematode control was investigated. After the mixture of strain BtTH109 and wheat bran was treated into rhizosphere of the tomato plants with nematode eggs, the stem height and root growth of plants increased. And the juveniles and eggs of nematode are not found in both roots of tomatoes and pot soil after cultured broth of the strain BtTH109 treated 4 times at 3 day-interval into rhizosphere of the infected tomatoes.

• 한국응용곤충학회지
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• 제21권3호
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• pp.146-152
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• 1982

Survey on potato parasitic nematodes has been undertaken in order to find distribution of the nemic fauna. 41 soil samples were taken from potato fields in Gyeongbug, Gyeongnam and Gangweon provinces. Twenty four species belonging to 16 different genera were identified. Potato cyst nematode, Globodera rostochiensis was not found in the areas. Potato-rot nematode, Ditylenchus destructor and stem nematode, Ditylenchus dipsaci were found from several potato fields and population density high and showed damage to the crops. Root-lesion nematode, Pratylenchus minyus, Pratylenchus penetrans, Pratytenchus thornei and Pratylenchus vulnus were found and their population of these four species were high depending on the fields. Root-knot nematode, Meloidogyne hapla and Meloidogyne incognita were found. M. hapla was found only in Gangweon province and the population density was high. M. incognita was found at Milyang in Gyeongnam province. Spiral nematode, Heticotylenchus digonichus, Helicotylenchus dihystera, Helicotylenchus pseudorobustus, Rotylenchus orientalis and Rotylenchus pini were found. Aphelenchoides saprophilus, Criconemoides informis, Ditylenchus destructor, D. dipsaci, Helicotylenchus digonichus, H. dihystera, Hemicriconemoides intermedius, Meloidogyne hapla, Psilenchus hilarulus, Pratylenchus minyus, and Xiphinema americanum were first found from potato fields in Korea.

• 한국응용곤충학회지
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• 제34권2호
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• pp.112-119
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• 1995

본 연구는 뿌리썩이선충(Pratylenchus vulnus)이 옥수수뿌리조직을 침입했을 때, 조직의 해부학적.생화학적 변화를 밝힘으로써 식물과 선충의 상호관계를 이해하고, 이들 정보를 바탕으로 선충저항성 작물의 육종 및 선별에 활용하기 위함이다. 옥수수뿌리 표피를 뚫고 들어온 선충은 뿌리 피층에 자리를 잡고, 세포벽을 파괴하면서 다른 세포로 이동한다. 마침내 선충들은 피층의 내피와 세근의 기부에 밀집했다. P.vuinus의 암컷들은 세포내에 공간(cavity)을 형성하여 그 속에 알을 낳는 습성을 지니고 있다. 선충에 의한 주된 피해양상은 세포벽이 파괴되고 부서져서 공간을 형성하는 것으로 나타난다. 이러한 현상은 세근의 기부에서도 관찰된다. 선충의 피해로 야기된 옥수수 뿌리의 생화학적 변화는 선충접종구와 무접종구간 총단백질양과 esterase활력조사를 통해 비교.분석되었다. Denaturing gel 상에서 총단백질양의 비교는 유의한 차이를 나타내지 않았고, esterase 의 pattern 및 활력에서도 유의할 만한 차이는 발견되지 않았다.

• 한국응용곤충학회지
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• 제33권3호
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• pp.159-162
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• 1994

경북의성 약용작물재배지에서 뿌리혹선충에 대한 발생생태를 조사하기 위하여 시기별 발생소장과 토성에 따른 선충의 증식정도, 토양심도 다른 뿌리혹선충의 서식밀도를 1991년부터 1992년까지 2개년간 조사한 결과는다음과 같다. 뿌리혹선충(M.hapla)의 발생소장을 조사한 결과 유충발생 최성기는 4월초순, 6월중순, 7월하순, 8월하순 등 4회였다. 토성과 뿌리혹선충과의 관계를 보면 사토와 사양토에서 뿌리혹선충의 난관 유충이 가장 많았고 식토에서는 밀도가 낮았다. 토양심도별 M.hapla 유충밀도는 작약포장에서 토심 15cm까지가 1,064~1,486마리로 가장 높았으며 50cm이상에서도 검출되었다.

• 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.