• Journal of the Korean Mathematical Society
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• v.54 no.3
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• pp.987-997
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• 2017

A deterministic model for the spread of pine wilt disease with asymptomatic carrier trees in the host pine population is designed and rigorously analyzed. We have taken four different classes for the trees, namely susceptible, exposed, asymptomatic carrier and infected, and two different classes for the vector population, namely susceptible and infected. A complete global analysis of the model is given, which reveals that the global dynamics of the disease is completely determined by the associated basic reproduction number, denoted by $\mathcal{R}_0$. If $\mathcal{R}_0$ is less than one, the disease-free equilibrium is globally asymptotically stable, and in such a case, the endemic equilibrium does not exist. If $\mathcal{R}_0$ is greater than one, the disease persists and the unique endemic equilibrium is globally asymptotically stable.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.70.1-70
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• 2003

It was investigated whether culture filtrates produced by X. fastiduosa could be used to determine varietal susceptibility in grape cultivars to anthracnose as a substitute for pathogen inoculation or field screening. Bioassay of grape leaves with culture filtrates showed that their phytotoxicities were active and host-selective. Ethyl acetate extracts from those also showed the toxicities and host selectivity among grape cultivars. The sensitive range of plants to culture filtrates and their ethyl acetate extracts was consistent with the host range to the pathogen. Susceptible cultivars were sensitive to even highly diluted culture filtrates but resistant cultivars were not affected even at original culture filtrates. Susceptible cultivars were sensitive to the undiluted culture filtrates than highly diluted culture filtrates and the younger leaves were the more sensitive to the culture filtrates and their ethyl acetate extracts in grapes.

• Korean Journal of Microbiology
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• v.6 no.1
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• pp.1-5
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• 1968

This experiment was undertaken the purpose of investigating the difference of the content of free amino acids in the diseased and healthy leaves of the resistance and susceptible rice varieties, to blast by means of paper chromatography. The results obtained are summarized as follows. (1) In the healthy and diseased leaves, the former was founded nine to tell sorts of free amino acids and later was observed eleven. In the both of leaves, alanine and valine were contained in larger amount, and aspartic acid, glycine and arginine were found relatively less in general. (2) In the diseased leaves, the amino acids were increased in quantity, especially glutamine and aspartic acid were remarkable, and cystine were found only in the diseased ones. (3) It seems to that the health leaves in all varieties were observed the amino acid contents, in notably increase and decrease, but in the diseased ones were not changed in amount. Tatacho, susceptible variety was more contained the amount of glutamine and aspartic acid than Zenith, resistance one.

• Research in Plant Disease
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• v.10 no.3
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• pp.203-208
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• 2004

The dominant isolates of Colletotrichum gloeosporioides from the red pepper anthracnose(both of the diseased plants and debris) was more pathogenic than the isolates of Colletotrichum acutatum of minorly isolated from Gyeong-buk, Korea. There were both of the G and R strains of cultural variants of Colletotrichum gloeosporioides, the G strain was more pathogenic than R strain. The cultivars of red-pepper, cv. 'Kumsegi' was the most susceptible and cv. 'papet' was the least susceptible in the pathogenicity test. The isolates of Colletotrichum gloeosporioides from other host plant such on sesame, safflower, yam, strawberry could infect to the red pepper plant also.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.145-149
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• 2003

Seeing inadequate disinfection and unhygenic condition in rearing area, use of disease resistant silkworm variety is the best option. In order to this, an attempt has been made to develop the resistance to Bombyx mori densonucleosis virus (BmDNV-2) into a susceptible silkworm breed Zhenon1 by cross breeding with a resistant silkworm breed SU12 and exposing the subsequent generations to BmDNV-2 followed by the selection of individuals from the surviving batches. After seven generation the evolved DNV-2 resistant strain showed the significantly higher resistance to BmDNV-2 than control Zhenon1. The economic characters of both of the breeds were almost on par.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.1
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• pp.13-16
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• 1995

In this study out of 3036 Black Bengal goats examined, 1755(57.80%) were infected with different types of metacestodes. The metacestodes were Cysticercus tenuicollis(54.54%), Coenurus cerebralis(6.32%) and hydatid cysts(11.13%). Animals > 18 months old were relatively more susceptible to Cysticercus tenuicollis and Coenurus cerebralis infection. On the contrary, animals > 8 months to 18 months old were more susceptible to hydatid infection, Both male and female goats were found to be equally infected with the metacestodes. A fully grown Coenurus cerebralis was also recovered from the abdominal muscles of a goat. In Cysticercus tenuicollis infection, pathological effects were not so marked. However, in few cases of Coenurus cerebralis infection the bones of the skull were found to become thin and soft. The hydatid cysts were found to develop in the vital organs by replacing the tissues, thus impairing normal functions.

• Korean journal of applied entomology
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• v.19 no.1 s.42
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• pp.1-4
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• 1980

Quantitative differences in pathogenicity of monoconidial subcultures of Pyricularia oryzae Cav. were examined. The subcultures had been isolated from a susceptible-(STL) and an intermediate type lesion (ITL), which originated from a single culture. The majority of the STL monoconidial subcultures produced more susceptible type lesions than did the ITL subcultures. The production of intermediate type lesions was similar in both groups of subcultures, whereas the ITL subcultures produced a high number of resistant type lesions. Within both groups, there was also some variation in numbers of lesions produced.

• Korean journal of applied entomology
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• v.19 no.1 s.42
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• pp.11-20
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• 1980

Percent penetration on a specific rice variety was more affected by blast fungus isolate or predisposition temperature than by temperature and isolate combinations. A susceptible variety tested remained continuously susceptible regardless of whether the variety was grown at different temperature regimes and exposed to isolates/races with differences in pathogenicity and virulence. The expression of virulence by a particular blast fungus isolate race was observed to be changed by subjecting rice host plants to different predisposing temperature conditions prior to inoculation.

• Corrosion Science and Technology
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• v.14 no.6
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• pp.253-260
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• 2015

The pitting behaviours of 304L and 316L stainless steels were investigated at $3^{\circ}C$ to $90^{\circ}C$ in 1 M solutions of NaCl, NaBr and NaI by potentiodynamic polarization. The temperature dependences of the pitting potential varied according to the anion, being near linear in bromide but exponential in chloride. As a result, at low temperatures grades 304L and 316L steel are most susceptible to pitting by bromide ions, while at high temperatures both stainless steels were more susceptible to pitting by small chloride anions than the larger bromide and iodide. Thus, increasing temperature appears to favour attack by smaller anions. This paper will attempt to rationalise both of the above findings in terms of the point defect model. Initial findings are that qualitatively this approach can be reasonably successful, but not at the quantitative level, possibly due to insufficient data on the mechanical properties of thin passive films.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.475-482
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• 2005

Many public facilities including roadway, railway, and embedded pipe lines in this country have been damaged by the repeated freezing and thawing of the soil during winter and spring every year. However, there are only few research results in field of frozen ground in this country. Also, there are no the formulation of the reasonable equation for frost penetration depths and of the criterion for identifing potentially frost-susceptible soil in design manual of pavement yet. Through this study it is anticipated to asses the frost action problem in roadway, railway, and water suppply lines and to establish the design criterion about pavement in seasonal cold region.