• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.133-138
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• 2003

Five seed kernel namely, Neem (Azadirachta indica A. Juss.), Pongamia (Pongamia glabra L. Pierre), Tamarind (Tamarindus indica L.), Mahua (Madhuca indica Gmel.) and Shikakai (Acacia cancinna De.) were tested against hatching of eggs and larval mortality of Meloidogyne incognita causing root knot disease in mulberry along with Furadan (Carbofuran) and Bionema (a bioformulation developed from Verticillium chlamydosporium) for comparison. Results revealed that highest hush-up of hatching was observed in Neem (77.40%) and Pongamia (75.99%) seed kernel extracts at 100% concentration over the check. Similarly, highest larval mortality was observed in Neem and Pongamia by 76.00% and 74.50%, respectively at 100% concentration after 72 hrs of exposure period. Pot culture studies revealed that pre-application of seed kernel powders (20 days before inoculation of nematode) found to be more effective in controlling the root knot disease than post application. In pre application of seed kernel powders, maximum reduction of root knots was observed in case of Neem seed kernel powder (54.85%) followed by Pongamia (51.9%). Similar trend was also observed in reduction of egg masses/plant and nematode population ／250 cc soil. Rest of the seed kernel extracts was found to be less effective in suppression of hatching, enhancing the larval mortality and controlling the root knot disease. However, application of Furadan and Bionema tested for the comparison were found to be more effective than seed kernel powders. The generated information seems to be useful in developing an ecofriendly integrated approach for the control of root knot nematode disease in mulberry.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.175-179
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• 2004

Trichoderma harzianum-THN1 parasitising the egg masses of root knot nematode Meloidogyne incognita was isolated from galled mulberry roots and evaluated for its potential to control root knot disease. In pot experiments root galling was reduced and leaf yield increased significantly following soil treatment with T. harzianum-THN1. The extracts obtained from the soils inoculated with T. harzianum-THN1 drastically inhibited the hatching of nematode eggs and the effect was irreversible even after the eggs were transferred to fresh water. The fungus was equally effective in controlling the disease in nematode infested mulberry garden under field conditions which was significant over the most commonly used egg parasitic fungus Paecilomyces lilacinus. The disease reduction recorded with T. harzianum was on par with the plants treated with the nematicide Carbofuran. The results suggest that T. harzianum- THN1 could be used as a potent ecofriendly biocontrol agent against M. incognita in mulberry without any residual toxicity to silkworms. T. harzianum- THN1 can form an important component of integrated disease management package in mulberry cultivation.

• 식물병연구
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• 제14권1호
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• pp.76-78
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• 2008

포항지역의 부추 연작 장해를 조사하는 중 부추에서는 처음으로 뿌리혹선충의 기생이 발견하여 보고한다. 부추에 기생하는 뿌리혹선충은 Meloidogyne incognita로 동정되었다. 연작 장해지에는 뿌리혹선충, 뿌리응애(Rhizoglyphus sp.), 시들음병(Fusarium oxysporum f. sp. cepae)등이 복합적으로 발생되고 있었지만 발생 빈도와 피해 정도를 보아 연작장해의 주요 원인은 뿌리혹선충이었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권1호
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• pp.57-61
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• 2007

For developing an integrated eco-friendly package against root knot disease complex of mulberry caused by the association of Meloidogyne incognita with Fusarium solani and F. oxysporum causing serious loss in terms of leaf yield and quality during cultivation, twenty botanical extracts at 5, 10 & 20% concentrations were screened under in vitro conditions. Among the extracts, Allium sativum followed by Lasownia inermis were found to be effective at 20% concentration against both the virulent fungi and nematode. Both the extracts reduced the mycelial growth of virulent fungi to an extent of 76-100%, inhibited the hatching of nematode eggs by 80-90% and 76-85% larval mortality over the control. The other extracts were found either moderately or poorly effective in reducing the growth of fungi, hatching of nematode eggs and enhancing the mortality of larvae. The two effective botanical extracts, which rated as strong inhibitors against both nematode and virulent fungi, can be utilized in developing an integrated ecofriendly technology for better management of root knot disease complex in mulberry.

• 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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• 제18권1호
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• pp.29-34
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• 2012

흰가루병과 뿌리혹선충병은 박과작물에 발생하는 매우 중요한 병이다. 본 실험은 시판된 국내 주요 박과작물(오이 21품종, 수박 9품종, 참외 7품종, 멜론 2품종)을 이용하여 흰가루병과 뿌리혹선충병에 대한 저항성을 평가하기 위하여 수행하였다. 흰가루병 조사는 정식 60일 후 조사하였다. 21개의 오이 품종 중 '강력삼척'과 '선호백침 다다기'는 중도저항성을 나타냈고 나머지 오이 품종은 모두 감수성이었다. 수박 품종은 모두 감수성을 나타냈다. 참외 품종에서는 저항성을 나타내는 품종은 없었으나 'PMR터보'와 'PMR빅토리' 2개 멜론 품종은 저항성을 나타냈다. 뿌리혹선충병은 유묘에 접종 45일 후 병 발생을 조사하였다. 오이 품종 '백봉다다기'가 중도저항성을 나타냈고 다른 20개의 오이 품종은 모두 감수성이었다. 수박 품종은 '달고나꿀'이 저항성이었으며 다른 품종은 중도저항성이거나 감수성이었고, 조사된 모든 참외와 멜론 품종은 뿌리혹선충병에 대하여 감수성이었다. 이상의 결과를 근거로 흰가루병 및 뿌리혹선충에 저항성인 품종은 박과작물의 유기재배에 이용할 수 있을 것이다.

• 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.

• The Plant Pathology Journal
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• 제26권2호
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• pp.149-153
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• 2010

Biological and structural mechanisms of the nematode disease development in chili pepper caused by the root-knot nematode, Meloidogyne incognita, were investigated. Out of 39 chili pepper cultivars/lines tested, six were found resistant, while 33 were susceptible to M. incognita, of which a susceptible cultivar Chilseongcho and three resistant cultivar/lines CM334, 02G132 and 03G53 with different resistance degrees were selected for microscopic studies on the disease development. Gall formation was greatly reduced in the resistant cultivars/lines. Nematode penetration occurred both in the susceptible and resistant chili pepper roots; however, the penetration rates were significantly lowered in the three resistant peppers compared to the susceptible pepper cv. Chilseongcho. In the susceptible pepper, giant cells were extensively formed with no discernible necrosis around the nematode feeding sites. In the highly resistant pepper cultivar CM334, no giant cell was formed, but extensive necrosis formation was observed around the penetrating nematodes. In the other two resistant pepper lines (02G132 and 03G53), both giant cells and prominent necroses were formed, and the necrotic responses appeared to inhibit the further development of giant cells or accelerate their early degeneration. Although the nematode penetration was retarded significantly in the resistant cultivar/lines, all of the above results suggest that the disease resistance of pepper may be related to post-infectional defense mechanisms (nematode growth and development) more than pre-infectional ones (penetration and establishment). Variations in structural modifications in the resistant cultivar/lines may reflect their genetic differences related to the nematode resistance.

• 식물병연구
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• 제23권4호
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• pp.348-354
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• 2017

2013년부터 2015년까지 국내 중부지방 시설재배지를 대상으로 지역별, 주요 작물별 뿌리혹선충의 감염 현황을 조사하였다. 총 132개 시설재배지 중에서 65개 포장(49%)에 뿌리혹선충이 감염되어 있었으며, 평균밀도는 토양 $100cm^3$ 당 뿌리혹선충 2기 유충 178마리로 나타났다(최저 1-최고 3,947마리). 시군별 감염률은 춘천이 80%로 가장 높았으며, 천안, 논산, 부여와 예산은 각각 68%, 36%, 33%와 30% 순으로 나타났다. 주요 작물별 뿌리혹선충 감염률은 토마토가 83%로 가장 높았으며, 오이(61%), 딸기(41%), 고추(30%), 수박(26%) 순으로 나타났다. 중부지방 시설재배지에서 검출된 뿌리혹선충 대표집단 15개체군의 분자생물학적 종 동정 결과, 고구마뿌리혹선충, 땅콩뿌리혹선충과 당근뿌리혹선충 3종이 각각 47%, 20%와 33%의 비율로 나타났다. 작물별로는 토마토에서 고구마뿌리혹선충, 땅콩뿌리혹선충과 당근뿌리혹선충 총 3종, 오이와 수박은 고구마뿌리혹선충과 땅콩뿌리혹선충 총 2종, 딸기와 상추에서는 당근뿌리혹선충 총 1종이 각각 검출되었다. 따라서, 뿌리혹선충 피해 확산 방지를 위해서는 작물별로 검출된 종을 고려한 방제대책 수립이 필요하다.

• The Plant Pathology Journal
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• 제38권6호
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• pp.583-592
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• 2022

Root-knot nematode disease is a widespread and catastrophic disease of tobacco. However, little is known about the relationship between rhizosphere bacterial community and root-knot nematode disease. This study used 16S rRNA gene sequencing and PICRUSt to assess bacterial community structure and function changes in rhizosphere soil from Meloidogyne incognita-infected tobacco plants. We studied the rhizosphere bacterial community structure of M. incognita-infected and uninfected tobacco plants through a paired comparison design in two regions of tobacco planting area, Yuxi and Jiuxiang of Yunnan Province, southwest China. According to the findings, M. incognita infection can alter the bacterial population in the soil. Uninfested soil has more operational taxonomic unit numbers and richness than infested soil. Principal Coordinate Analysis revealed clear separations between bacterial communities from infested and uninfested soil, indicating that different infection conditions resulted in significantly different bacterial community structures in soils. Firmicutes was prevalent in infested soil, but Chloroflexi and Acidobacteria were prevalent in uninfested soil. Sphingomonas, Streptomyces, and Bradyrhizobium were the dominant bacteria genera, and their abundance were higher in infested soil. By PICRUSt analysis, some metabolism-related functions and signal transduction functions of the rhizosphere bacterial community in the M. incognita infection-tobacco plants had a higher relative abundance than those uninfected. As a result, rhizosphere soils from tobacco plants infected with M. incognita showed considerable bacterial community structure and function alterations.