• 한국토양동물학회지
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• 제8권1_2호
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• pp.27-31
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• 2003

당근뿌리혹선충(Meloidogyne hapla)이 더덕(Codonopsis lanceolata)ml 생장에 미치는 영향을 구명하기 위하여 pot와 포장에서 실험을 수행하였다. 그 결과 당근뿌리혹선충의 밀도가 증가함에 따라 pot 실험에서는 더덕의 덩굴생장이 60%, 뿌리생장이 45% 억제되었다. 포장 실험에서는 밀도 수준별 생육차이가 뚜렷하지 않았다. 이 결과는 더덕 구당 선충 접종 밀도가 낮아 피해수준에 도달하지 않은 것으로 사료된다.

• The Plant Pathology Journal
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• 제36권3호
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• pp.297-302
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• 2020

Root-knot nematodes (Meloidogyne spp.) are the most destructive group of plant-parasitic nematodes. Plants infected by Meloidogyne spp. develop above-ground symptoms, stunting, yellowing, nutrient deficiencies, and gall formations with typical hook-shaped root tips. Infected plants experience yield losses. During 2018-2019 survey, leaf chlorosis rice plants were found in 206 fields of 67 counties in Guangxi, China, around 30 days after transplanting. Galls and hooked tips on the roots and pear-shaped females were observed. About 32.04% of fields were infested with the nematode. The nematodes were identified as Meloidogyne graminicola base on morphological and molecular analysis. To the best of our knowledge, this is the first report of M. graminicola on rice plants in Guangxi, China. The results of this study urge the discovery of resistant cultivars and the development of management strategies.

• The Plant Pathology Journal
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• 제30권4호
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• pp.450-455
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• 2014

This study sought to control the root-knot nematode (RKN) Meloidogyne incognita using benign organo-chemicals. Second-stage juveniles (J2) of RKN were exposed to dilutions (1.0%, 0.5%, 0.2%, and 0.1%) of acetic acid (AA), lactic acid (LA), and their mixtures (MX). The nematode bodies were disrupted severely and moderately by vacuolations in 0.5% of MX and single organic acids, respectively, suggesting toxicity of MX may be higher than AA and LA. The mortality of J2 was 100% at all concentrations of AA and MX and only at 1.0% and 0.5% of LA, which lowered slightly at 0.2% and greatly at 0.1% of LA. This suggests the nematicidal activity of MX may be mostly derived from AA together with supplementary LA toxicity. MX was applied to chili pepper plants inoculated with about 1,000 J2, for which root-knot gall formations and plant growths were examined 4 weeks after inoculation. The root gall formation was completely inhibited by 0.5% MX and standard and double concentrations of fosthiazate; and inhibited 92.9% and 57.1% by 0.2% and 0.1% MX, respectively. Shoot height, shoot weight, and root weight were not significantly ($P{\leq}0.05$) different among all treatments and the untreated and non-inoculated controls. All of these results suggest that the mixture of the organic acids may have a potential to be developed as an eco-friendly nematode control agent that needs to be supported by the more nematode control experiments in fields.

• 한국응용곤충학회지
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• 제27권1호
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• pp.1-5
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• 1988

시설원예 재배지의 viny1 house에서 문제가 예견되는 뿌리혹은선충(Meloidogyne spp.)을 방제하기 위하여 태양열을 이용한 토양선독을 8월 1일부터 8월31일 까지 실시한 결과는 다음과 같다. 뿌리혹은선충은 $40^{\circ}C$ 체온기내에서 48시간 이내에 모두 사멸되었다. 왜도 $30^{\circ}C$ 때 이중으로 비닐피복된 지표하 5cm 깊이에서의 체구지온은 $48.7^{\circ}C$, 15cm깊이에서는 $45.2^{\circ}C$, 30cm 깊이에서는 $36.0^{\circ}C$에 달하였다. 지중온도가 $40^{\circ}C$이상 상승한 일수는 1986년 8월 5cm 깊이에서 17일, 15cm깊이에서 14일간이였다. 비닐 이중피복에 따른 뿌리혹선충의 방제효과를 보면 지표하 5cm 깊이에서 뿌리혹선충은 완전 사멸되었으며 15cm 깊이에서 생존 선충수는 1마리, 30cm 깊이에서는 2마리로써 이중피복에 의한 사멸전과는 대단히 높았다.

• 한국유기농업학회지
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• 제30권1호
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• pp.103-118
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• 2022

Photorhabdus is a bacterial symbiont of entomopathogenic nematodes of the genus Heterorhabditis in the family Heterorhabditidae. Photorhabdus is known to have nematicidal activity in addition to insecticidal activity. P. temperata isolated from Korean indigenous H. megidis Gwangju strain also produced high control efficacy against root-knot nematode Meloidogyne incognita and root-lesion nematode Pratylenchus penetrans. P. temperata has drawn interest as a potential bionematicide for the control of root-knot nematodes thereby. For the registration as an organic agricultural material, the toxicity of P. temperata was assessed by the acute toxicity test in carp (Cyprinus carpio) and acute oral and dermal toxicity tests in Sprague-Dawley rat (Rattus norvegicus) in compliance with the guidelines of the Rural Development Administration (RDA). In the acute toxicity test in fish, neither lethality nor abnormal responses of carp were observed. Body length and weight of carp and changes in DO concentrations and pH values were not significantly different between the treated group and the untreated control. In the acute oral and dermal toxicity tests, clinical signs, abnormal behavior, mortality, and pathological findings were not observed in all the experimental rats. The weight increment of all rats was normal. Acute toxicity results of P. temperata in fish and rats belonged to categories III, IV, and IV of RDA, respectively. Toxicity results of the present study indicated that P. temperata could be a safe and promising bionematicide against root-knot nematodes and root lesion nematode.

• 한국토양비료학회지
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• 제49권4호
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• pp.401-408
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• 2016

The present study described the isolation of 2-methylbutyric acid (2-MBA) produced from Bacillus pumilus L1, to subsequently investigate its nematicidal activity for the control of the root-knot nematode. The results showed that 2-MBA could be purified by chromatographic techniques and was identified using nuclear magnetic resonance and liquid chromatography-mass spectrometry. Crude extract and partially purified compounds had a significant effect on the inhibition of egg hatchability and second-stage juvenile (J2) mortality. A dose-dependent effect of 2-MBA was observed for J2 mortality and egg hatchability. Egg hatchability was 69.2%, 59.9%, 32.7%, and 0.0% at 125, 250, 500, and $1000{\mu}g\;mL^{-1}$ of 2-MBA after 4 d of incubation, respectively. Meanwhile, J2 mortality was in the range of 24.4%-100.0% after 2 d of incubation, depending on the concentrations of 2-MBA used. A pot experiment also demonstrated that treatment of B. pumilus L1 culture caused a significant reduction in the number of galls, egg masses, and J2 population than that of the tap water (TW) control. However, as the B. pumilus L1 culture concentration was decreased, the efficacy of nematode control by treatment of B. pumilus L1 culture was reduced compared to that of TW. B. pumilus L1 inoculation at different concentrations also promoted cucumber plant growth. Therefore, our study demonstrated the potential of 2-MBA from B. pumilus L1 as a biocontrol agent against the root-knot nematode and a plant growth promoter for cucumber plants.

• The Plant Pathology Journal
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• 제34권6호
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• pp.544-554
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• 2018

Tomato (Solanum lycopersicum) production in Ghana is limited by the root-knot nematode (Meloidogyne incognita, and yield losses over 70% have been experienced in farmer fields. Major management strategies of the root-knot nematode (RKN), such as rotation and nematicide application, and crop rotation are either little efficient and harmful to environments, with high control cost, respectively. Therefore, this study aims to examine morphometric variations of RKN populations in Ghana, using principal component analysis (PCA), of which the information can be utilized for the development of tomato cultivars resistant to RKN. Ninety (90) second-stage juveniles (J2) and 16 adult males of M. incognita were morphometrically characterized. Six and five morphometric variables were measured for adult males and second-stage juveniles (J2) respectively. Morphological measurements showed differences among the adult males and second-stage juveniles (J2). A plot of PC1 and PC2 for M. incognita male populations showed clustering into three main groups. Populations from Asuosu and Afrancho (Group I) were more closely related compared to populations from Tuobodom and Vea (Group II). There was however a single nematode from Afrancho (AF4) that fell into Group III. Biplots for male populations indicate, body length, DEGO, greatest body width, and gubernaculum length serving as variables distinguishing Group 1 and Group 2 populations. These same groupings from the PCA were reflected in the dendogram generated using Agglomerative Hierarchical Clustering (AHC). This study provides the first report on morphometric characterisation of M. incognita male and juvenile populations in Ghana showing significant morphological variation.

• 원예과학기술지
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• 제32권2호
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• pp.217-226
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• 2014

2012년 충남 부여에서 뿌리혹선충(Meloidogyne incognita, M. arenaria 및 M. javanica)에 대한 저항성 유전자 Mi를 가지고 있는 토마토 '유니콘' 품종에서 뿌리혹선충병이 크게 발생하였다. 이로부터 분리한 뿌리혹선충은 종 특이적 프라이머 2개에 의한 분석한 결과, M. incognita로 동정되었다. 이 선충에 의한 감수성 1개와 저항성 3개 토마토 품종의 뿌리혹선충병 발생을 조사하였는데, 실험한 모든 온도 조건에서 실험한 품종 모두는 높은 감수성을 보였다. 그리고 시판 중인 토마토 33개 품종(뿌리혹선충 저항성 25개와 감수성 8개)의 이 선충에 대한 저항성 정도를 조사한 결과, 실험한 모든 품종들은 각 품종의 뿌리혹선충 저항성과 관계없이 유사한 정도의 높은 감수성을 나타냈다. 본 논문은 우리나라에서 Mi 저항성 토마토 품종에 뿌리혹선충병을 일으키는 M. incognita 발생을 처음으로 보고하는 것이다. 한편, 새로운 저항성 육종 소재를 찾기 위한 효율적인 저항성 검정 방법을 확립하기 위하여, 이 선충의 접종 농도, 토마토 생육 시기 및 이식 시기 등의 다양한 발병 조건에 따른 토마토 4개 품종의 뿌리혹선충병 발생을 조사하였다. 접종원의 접종 농도가 증가할수록 토마토의 뿌리혹선충병 발생은 농도 의존적으로 증가하였다. 하지만 토마토의 생육 시기 및 이식 시기에 따른 토마토의 뿌리혹선충병 발생은 유의성 있는 차이가 없었다. 이들 결과들을 바탕으로 Mi-virulent M. incognita에 대한 토마토의 저항성 정도를 검정하기 위한 효율적인 방법을 제안하는 바이다.

• The Plant Pathology Journal
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• 제35권1호
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• pp.51-62
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• 2019

A great variable response was observed when PP-3 and PP-J encumbered with 116 populations of root knot nematode (RKN) at two different temperatures ($25{\pm}2^{\circ}C$ and $30{\pm}2^{\circ}C$) and concentrations ($10^4$ and $10^5$ spores/ml). The PCR reaction amplified intergenic region between cytochrome oxidase subunit II gene (COII) and large subunit of rRNA gene (lrRNA) of the mitochondrial genome of different RKN species. The primer C2F3 and 1108 identified M. incognita with the highest frequency (52.6%) followed by M. javanica (36.8%) and M. arenaria (10.5%). The sizes of PCR products were 1.7 kb for M. incognita and M. javanica populations while populations of M. arenaria produced 1.1 kb fragment. The digestion with Hinf I yielded three different fragment length patterns on 1.5 % agarose gel. From current research it is concluded that intra-Meloidogyne genetic variability exist in RKN populations which have better encumbrance with P. penetrans.

• 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.