• Mycobiology
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• v.35 no.3
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• pp.159-161
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• 2007

Pine tree death caused by pine wood nematode(PWN) involves phoretic relationships between PWN and its vector Japanese pine sawyer beetle(JPS). In an effort to understand the diversity of fungi involved in PWN life cycle, a total of 176 fungal isolates were collected from PWNs, adults and larvae of JPS, PWN-diseased Japanese black pine that was cut down in 2005 at Jinju, Korea. Based on microscopic observation and colony morphology, and sequence analysis of the ITS rDNA, the fungal isolates were identified at the level of genus. Three genera including Mucor, Ophiostoma, and Penicillium were identified from PWN. Two genera of Ophiostoma and Penicillium were discovered from JPS larvae. Frpm JPS adult beetles, nine genera of Aspergillus, Gibberalla, Hypocrea, Irpex, Leptosphaeria, Ophiostoma, Penicillium, and Plectosphaerella and unknown basidio-mycetes were found. Ten genera from PWN-infected weed were confirmed as Bionectria, Botrytis, Camarops, Fusarium, Hypocrea, Nectria, Mucor, Ophiostoma, Penicillium, and Trichoderma. Penicillium and Ophiostoma were commonly distributed on PWN and its vector and host. This is first report of the fungi associated with PWN and its vector and host in Korea.

• Natural Product Sciences
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• v.24 no.4
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• pp.272-283
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• 2018

The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-${\alpha}$-L-rhamnoside (Afzelin) (2), quercetin-3-O-${\alpha}$-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-${\alpha}$-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of $200{\mu}g/mL$. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.

• Korean journal of applied entomology
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• v.19 no.3 s.44
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• pp.153-155
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• 1980

In pot experiment, relations between bulb nemationde, Ditylenchus dipsaci, and growth and yield of garlic were followed. There was no effect of height growth on bulb nematode, but growth of volume was reduced at more than 250 nematodes per pot. Yield loss of garlic was more than $20\%$ when nematode density was about 30 per bulb in late-April. Tolerance limit should be about 20 nematodes per bulb at early growing stage. Reproduction of bulb nematode was good when initial population had been low.

• Korean journal of applied entomology
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• v.14 no.1 s.22
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• pp.35-36
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• 1975

An experiment was carried out to know bow the rice root nematode, Hirschmanniella cryzae affects the root browning of rice pant growing in various combinations of media. In sterilized conditions of growing media, the root browning of rice plant was slightly promoted by the presence of the rice root nematode, while the entire roots were stained to brown in nonsterilized conditions of growing media. It seems that the root browning is due mainly to soil micro-organisms other than nematode which promotes it slightly under sterilized conditions.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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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.

• Korean journal of applied entomology
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• v.12 no.4 s.17
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• pp.143-146
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• 1973

A greenhouse experiment was conducted to find out the influence of the inoculation density of Aphelenchoides besseyi on the growth of rice plant and the body length of female nematode. The rice plants showed reduced height, number of tillers and dry weight of plant when the nematode was inoculated. The body length of female nematode significantly decreased as the initial population density increased.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.227-232
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• 1994

In order to microbially control root-knot nematode(Meloidogyne incognita) in tomato, a strain BtTH109 of Bacillus thuringiensis producing root-knot nematocidal toxin was isolated. The strain BtTH109 was identified B. thuringiensis subsp. indiana(serotype 16) based on flagella antigenicity, biochemical properties, and morphological charcateristics. The strain BtTH109 have extracellularly produced a root-knot nematocidal toxin, which was very toxic against not only egghatch but also the 2nd-nematode larva of root-knot nematode in vitro.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.912-924
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• 2002

Disease susceptibility is linked to nutritional status for a wide range of human and animal diseases. Nutritional status can influence both resistance (ability to resist the pathogen) and resilience (ability to tolerate or ameliorate the effects of the pathogen). This review focuses on the nutritional modulation of gastro-intestinal nematode infection in domestic ruminants, primarily sheep. It highlights the duality of the adverse consequences of infection on host nutritional status and the adverse consequences of poor host nutritional status on resistance to infection. Central to both phenomena is the complex, gut-based immune response to gastrointestinal nematode infection. The potential for strategic nutritional supplementation to enhance host resistance and resilience is reviewed together with recent findings on responses to increased ME supply, and long term effects on host immunity of short term protein supplementation.

• The Plant Pathology Journal
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• v.17 no.3
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• pp.159-163
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• 2001

Influence of soil temperature [accumulated degree-day for the base temperature $5^{\circ}$($\textrm{DD}_5$)] on the development of Meloidogyne arenaria were studied in a winter grown oriental melon greenhouse in Seongju, Korea. Egg masses were first observed on roots at the accumulation of 565 $\textrm{DD}_5$(40 days after transplanting), suggesting that the nematode has completed the first generation in 40 days. Second-stage juveniles (J2) densities were lowest at 863 $\textrm{DD}_5$ in April, first increased at 1,334 $\textrm{DD}_5$ in May, peaked at 2,951 $\textrm{DD}_5$ in July, and decliner thereafter. Development of egg masses and J2 density in soil revealed that M. arenaria could develop in 7-8 generations in a year in the greenhouse. Degree-day monitoring, therefore, could aid to predict nematode development in soil and can be valuable tool a to develop root-knot nematode control strategies.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.39-46
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• 1995

Ditylenchus destructor isolated from diseased ginseng roots was cultured on ginseng calli, fungal mycelium (Fusarium solani), carrot discs and radish sprouts. Effects of temperature, organic material and flooding on the nematode population changes were examined. D. destructor multiplied readily on the culture media except radish sprout medium, and was cultured best on the fungal culture at 2$0^{\circ}C$. Feeding of the fungal hypha and radish root hairs, molting and mating in the fungal culture medium were observed. Addition of organic materials (perilla, sesame, soybean and ginseng leaves) in soil significantly increased Aphelenchus avenae and saprophytic nematode populations, while D. destructor populations changed little and the nematode population growths were limited by the organic amendments (except sesame leaves). The nematode populations in soil including D. destructor were decreased by flooding. The results indicate that D. destructor may survive but not multiply readily in soil without host plants and that it can be effectively controlled by flooding.