• The Plant Pathology Journal
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• v.31 no.4
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• pp.421-427
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• 2015

Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen $Elsino{\ddot{e}}$ fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1997.06a
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• pp.47-55
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• 1997

Plant growth promoting fungi(PGPF) obtained from zoysiagrass rhizosphere offer dual advantages - induse systemic disease resistance response in cucumber to C. orbiculare infection and cause enhancement of plant growth and increase yield. PGPF protected plants either by colonizing roots or by their metabolites. PGPF offer an advantage by protecting plants for more than 9 weeks and 6 week in the greenhouse and field. PGPF-induced plants limited pathogen spore germination and decreased the number of infection hyphae on the leaf, and increased lignification at places of attempted pathogen infection, thus reducing the pathogen spread. PGPF elicited increased activities of chitinascs, glucanases, peroxidase, polyphenol oxidase, and phenylalanine ammonia lyase to C. orbiculare infection in cucumber plants. The role of PGPF in elevating cucumber defense response to pathogen infection suggests potential application of PGPF as biological control agents.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.22 no.4
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• pp.253-287
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• 2018

This paper studies the global stability of a class of discrete-time pathogen infection models with latently infected cells. The rate of pathogens infect the susceptible cells is taken as bilinear, saturation and general. The continuous-time models are discretized by using nonstandard finite difference scheme. The basic and global properties of the models are established. The global stability analysis of the equilibria is performed using Lyapunov method. The theoretical results are illustrated by numerical simulations.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.113-120
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• 2009

Microscopic study of chili pepper (Capsicum annuum L.) infected with Phytophthora capsici, causing Phytophthora blight of chili pepper, was conducted to compare histological and cytological characteristics in the root and stem of susceptible (C. annuum cv. Bugang) and resistant (C. annuum cv. CM334) pepper cultivars. The susceptible pepper roots and stems were extensively penetrated and invaded by the pathogen initially into epidermal cells and later cortical and vascular cells. Host cell walls adjacent to and invaded by the infecting hyphae were partially dissolved and structurally loosened with fine fibrillar materials probably by cell wall-degrading enzymes of the pathogen. In the resistant pepper, the pathogen remained on root epidermal surface at one day after inoculation, embedded and captured in root exudation materials composed of proteins and polysaccharides. Also the pathogen appeared to be blocked in its progression at the early infection stages by thickened middle lamellae. At 3 days after inoculation, the oomycete hyphae were still confined to epidermal cells of the root and at most outer peripheral cortical cells of the stem, resulting from their invasion blocked by wound periderms formed underneath the infection sites and/or cell wall appositions bounding the hyphal protrusions. All of these aspects suggest that limitation of disease development in the resistant pepper may be due to the inhibition of the pathogen penetration, infection, invasion, and colonization by the defense structures such as root exudation materials, thickened middle lamellae, wound peridems and cell wall appositions.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.767-768
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• 2005

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.86.2-86
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• 1999

• The Plant Pathology Journal
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• v.32 no.3
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• pp.260-265
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• 2016

We observed the changes in aggressiveness and fecundity of the anthracnose pathogen Colletotrichum acutatum on hot pepper, under the ambient and the twice-ambient treatments. Artificial infection was repeated over 100 cycles for ambient ($25^{\circ}C/400ppm$ $CO_2$) and twice-ambient ($30^{\circ}C/700ppm$ $CO_2$) growth chamber conditions, over 3 years. During repeated infection cycles (ICs) on green-pepper fruits, the aggressiveness (incidence [% of diseased fruits among 20 inoculated fruits] and severity [lesion length in mm] of infection) and fecundity (the average number of spores per five lesions) of the pathogen were measured in each cycle and compared between the ambient and twice-ambient treatments, and also between the early (ICs 31-50) and late (ICs 81-100) generations. In summary, the pathogen's aggressiveness and fecundity were significantly lower in the late generation. It is likely that aggressiveness and fecundity of C. acutatum may be reduced as global $CO_2$ and temperatures increase.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.1
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• pp.37-44
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• 2007

To investigate the response of proline and ammonia to pathogen infection, plant growth and relevant chemical component were examined in large patch-infected or healthy (control) zoysiagrass during 6 days after treatment. Pathogen-infection increased root mortality by 30% compared to control. Soluble protein was not significantly affected by pathogen-infection except in the leaf at day 6. Ammonia concentration also increased significantly in both leaves and roots of pathogen-infected plants. Proline concentration in leaves and roots increased to 3.4- and 4.5-fold, respectively, compared to those of control at day 6. These results suggest that proline accumulation may be a sensitive biochemical indicator representing the stress intensity caused by pathogen infection in zoysiagrass.

• 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.

• Infection and chemotherapy
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• v.50 no.4
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• pp.362-366
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• 2018

Millerozyma farinosa (formerly Pichia farinosa) is halotolerant yeast mainly found in food and ubiquitous in the environment. It was a rare yeast pathogen, but it has recently emerged as a cause of fungemia in immunocompromised patients. Optimal therapy for invasive fungal infection by this pathogen remains unclear. We report a case of catheter related blood stream infection caused by M. farinosa in a 71-year-old patient who recovered successfully after removal of the central venous catheter and treatment with micafungin.