• The Korean Journal of Mycology
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• v.29 no.2
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• pp.116-122
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• 2001

An isolate of the prospective hyperparasite, Ampelomyces quisqualis 94013 (AQ94013) was selected for the use of biological control of cucumber powdery mildew caused by Sphaerotheca fuliginea. Examination for the parasitism processes by scanning electron microscopy and light microscopy showed that conidia of AQ49013 germinated on conidia, conidiophores and hyphae of Sphaerotheca fuliginea four hours after inoculation. Appressorium-like structures were developed and attached to the hyphae of S. fuliginea seventeen hours after inoculation. Hyphae of AQ94013 penetrated into hyphae of S. fuliginea twenty-four hours after inoculation. Pycnidia of AQ94013 were produced in the hyphae and the basal part of conidiophores of S. fuliginea fourty four hours after inoculation. The pycnidia of AQ94013 matured foully eight hours after inoculation, and the conidia were discharged from the ostioles of the pycnidia fifty two hours after the inoculation. At the same time, hyphae and conidiophores of S. fuliginea were distorted and died. Also, concentrated culture filtrate and culture filtrate of AQ94013 had not suppressed the cucumber powdery mildew fungus as water treatment. Therefore, mode of action of AQ94013 was assumed to be parasitism on powdery mildew fungi.

• Parasites, Hosts and Diseases
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• v.54 no.5
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• pp.555-563
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• 2016

For several years, we have conducted a series of studies on the patterns of ancient parasitism prevailing in the soil of rural and urban areas of past Kingdom of Korea. Actually, during our survey of paleoparasitology in archaeological sites of Korean peninsula, numerous ancient parasite eggs were discovered in the samples from the city districts of Hansung (Joseon) and Buyeo (Baikje), the palace moat at Gyeongju (Silla), shell-midden site at Bonghwang-dong (Silla to Joseon), and the reservoir found in Hwawangsansung fortress (Silla). By the paleoparasitological studies, with respect to parasitism in the high-density populations of ancient towns and cities, we have managed to catch glimpses of the patterns prevalent therein: a serious parasitic contamination of the soil in ancient urban areas, but not in rural areas of the past. Our historical research also proposed the plausible mechanism of parasite infection very serious indeed among urban populations in Korean history. Although city dwelling doubtless has accrued significant benefits for people and populations with agriculture, it can be equally supposed that living in such highly populated areas might have facilitated the spread of parasite infection.

• Ocean and Polar Research
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• v.43 no.4
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• pp.365-370
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• 2021

Manila clam Ruditapes philippinarum is present at high rates of density in tidal flats in Cheonsu Bay on the west coast of Korea, where clams often exhibit mass mortalities in late summer. We monitored the pathologic condition of clams at Hwangdo tidal flat (HD) to understand the parasitic impacts on clam fitness. Manila clams were fully ripe in July and spawned during August and September, as the histology indicated. The histology revealed that clams in HD tidal flats were heavily infected by the protozoa parasite Perkinsus olseni, as the monthly prevalence ranged from 53% (September) to 93% (August). In addition, Manila clams were co-infected by the metazoan parasite Cercaria tapetis and Parvatrema duboisi with the prevalence of 0-33% and 0-14%, respectively. Massive hemocyte infiltration and subsequent inflammation were commonly observed from the gills of P. olseni infected clams. Clusters of P. olseni trophozoites and heavy hemocyte infiltration were also observed from the female gonad, suggesting that P. olseni interferes with host gonad maturation. The larval trematode occupied almost the entire host gonad, resulting in gonad castration. In addition, Metacercaria of P. duboisi were observed from the subsurface of the mantle. Ray's fluid thioglycollate medium assay (RFTM) indicated that clams collected in August and September contained approximately 4.0×106 P. olseni cells/g gills. Condition Index (CI) declined gradually from spring to early summer, and the decline in CI was interpreted as a consequence of the heavy parasitism, as the parasites drain the host's net energy to be used in somatic growth and gamete production.

• Ocean and Polar Research
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• v.44 no.4
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• pp.319-329
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• 2022

The paramyxean parasite Marteilioides chungmuensis infects the cytoplasm of the eggs of Pacific oysters Crassostrea gigas , resulting in spawning failure of the infected females. Such infected eggs appear as bump-like nodules on the body in late fall when most of the uninfected females complete spawning. In this study, we estimated the quantity of the infected eggs using an enzyme-linked immunosorbent assay (ELISA), which is destroyed by M. chungmuensis parasitism. In December, the infected oysters collected from Tongyoung on the south coast exhibited numerous yellowish bump-like nodules as signs of infection. In histology, the infected oysters exhibited mature eggs in the follicle, which were heavily infiltrated by hemocytes. ELISA indicated that the infected egg mass accounted for 7.52±5.50 percent of the body weight, suggesting the ovarian parasite causes substantial reproductive loss. Histology also indicated that the infected oysters are in a poor nutritional condition, as the digestive gland atrophy (DGA) level is comparatively higher than the uninfected oyster. The total carbohydrate contents in the infected oysters (108.68±44.41 mg/g dry wt) were significantly lower than in uninfected oysters (269.76±50.97 mg/g dry wt), suggesting that M. chungmuensis parasitism also affected the energy storage capacity of the host during the resting stage.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.37-40
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• 1986

We surveyed the IRRI farm to determine the extent of parasitization of yellow stemborer egg masses. The egg masses were randomly collected at weekly intervals from July to October 1984 from rice fields, 15-20 days after transplanting, and brought to the laboratory for collection of emerging parasites. Three species of hymenopterous parasitoids-Tetrasticus schoenobii, Telenomus rowani, and Trichogramma japonicum-were found from 700 egg masses. We introduced a method to calculate percent parasitism as based on parasite biology and behaviour. Among the three species, the combination of T. rowani and T. japonicum was the highest multiparasitization of yellow stem borer egg masses, and T. rowani, a solitary parasite had the highest number based on immature and adult stages counted. However, T. schoenobii may be the most efficient parasite because two to four host eggs are needed to complete the larval period, and it took $10{\sim}14$ days for one generation.

• Mycobiology
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• v.40 no.2
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• pp.129-133
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• 2012

A new disease, the slippery scar, was investigated in cultivated bags of Auricularia polytricha. This fungus was isolated from the infected mycelia of cultivated bags. Based on morphological observation, rDNA-internal transcribed spacer and 18S sequence analysis, this pathogen was identified as the Ascomycete Scytalidium lignicola. According to Koch's Postulation, the pathogenicity of S. lignicola to the mycelia of A. polytricha was confirmed. The parasitism of this fungus on mushroom mycelia in China has not been reported before.

• Animal Systematics, Evolution and Diversity
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• v.29 no.1
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• pp.70-73
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• 2013

Diadegma fenestrale is known as a parasitoid of the potato tuber moth, Phthorimaea operculella. The potato tuber moth, Phthorimaea operculella (Zeller) is one of the most destructive pest of potatoes. Also, we found this species attacking the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae). Ratio of parasitism is 20-30% and cocoon of lepidopteran was parasitic ichneumonid species after 3 days. This species and the genus Diadegma are recorded for the first time from Korea. In this paper, description of the parasitoid and photographs of the diagnostic characteristics are provided.

• Journal of the korean veterinary medical association
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• v.20 no.2
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• pp.97-102
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• 1984

It is difficult to find the reports on the prevalence of the internal parasitisms of the goat in Korea. In the present studies, the internal parasitisms of the Korean native goats in Chonnam area were examined mainly by fecal examinations. For the identif

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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• pp.39-39
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• 2003

Balantidiasis is an infectious disease worldwide which is produced by a protozoan Balantidium coli. This single-celled organism is characterized by their large size ranging from 50 $\mu\textrm{m}$ to more than 500 $\mu\textrm{m}$ [1] which indicated by the presence of cilia on its cell surface. The parasite occurs in the lumen of cecum and colon of swine, humans and nonhuman primates as commensal, but can turn opportunist and invade injury tissues by other diseases [2]. It is difficult to diagnose the disease clinically since they are asymptomatic [3]; and can be complicated with other disease or parasitism. Here we report the incidental findings of Balantidiasis in the lymphatic ducts of gastric lymph node of Barbary sheep (Ammotragus lervia). (omitted)

• Korean Journal of Veterinary Research
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• v.22 no.2
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• pp.259-263
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• 1982

Observations were made on the infection rate of common internal parasites in dogs in Kwangju area from January to March, 1982. Dog's stools were collected from veterinary hospitals, houses, intensive dog-rearing places and sidewalks. On the basis of egg counting, the following results were obtained; 1. Of 464 fecal samples, 73.5% were appeared as positive. 2. Dogs from veterinary hospitals and intensive dog-rearing places have higher infection rates than others. 3. Of the parasites detected, Toxocara canis was the most commonly encountered (23.7%). 4. Ascarids, flukes and coccidia were more prevalent in pups than in mature dogs, whereas bookworms were detected less often in young dogs than in older ones. 5. There were significant (p<0.01) differences among age categories for all parasites except tapeworms.