• Research in Plant Disease
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• v.29 no.3
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• pp.316-320
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• 2023

Recently, the domestic plant disease control policy for fire blight has been implemented partial control in addition to burial control. In this study, an on-site management survey was conducted targeting orchards that implemented partial disease control from 2019 to 2020 in order to find efficient implementation methods for partial disease control. As a result of an investigation into 22 pear and apple orchards in Cheonan and Chungju, 7 orchards were buried. The upper part of the cut infected plants was burned at 16 orchards and covered with plastic vinyl after lime treatment at 6 orchards. The lower stumps of cut infected plants were burned at 7 orchards and covered with plastic vinyl after lime treatment at 15 orchards. There were two orchards where suckers appeared on the stumps even though covers were applied. There was no infection by Erwinia amylovora in the suckers. The conservation condition of lime treatment was good, but warning signs were absent at 6 orchards. Most orchards treated the stumps and surrounding areas with glyphosate-isopropylamine herbicide. The effect of partial control was judged to be safe.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.99-101
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• 1984

Oochoristica pauriensis n.sp. has been described and figured from Hemidactylus brooki (Gray) and H. flaviviridis (Ruppell) on size of strobila, scolex, suckers, testes, ovary, eggs and oncosphere, and number of testes. The new specIes has been compared with close species.

• Parasites, Hosts and Diseases
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• v.40 no.3
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• pp.107-112
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• 2002

A scanning electron microscopic study was performed on the surface ultrastructure of Pygidiopsis summa (Digenea: Heterophyidae) adults. Metacercariae were collected from gills and muscles of mullets (Mugil cephalus) caught in a known endemic area, and adult flukes were harvested from dogs after 8 weeks of experimental infection. The worm was calabash form with its posterior part broader than the anterior part. Tegumental spines were densely distributed over the body surface, except on the suckers and genital apparatus, and around the excretory pore. Well differentiated spines were observed on the anterior half of the body, with 14-16 tips ventrally, and 19-20 tips dorsally. On the oral sucker. three pairs of type I sensory papillae (uni-ciliated knob-like swellings) and one pair of type II sensory papillae (aciliated round-swellings) were observed on the anterior and posterior parts of the lip, respectively. On the lip of the ventral sucker, one pair of type II sensory papillae was distributed only on its posterior part. Sperms were seen emerging from or entering into the genital apparatus. The results showed that the surface ultrastructure of P. summa was unique among the heterophyid trematodes, especially in digitation of tegumental spines and in distribution of sensory papillae on oral and ventral suckers.

• Parasites, Hosts and Diseases
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• v.46 no.2
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• pp.87-90
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• 2008

Gynaecotyla squatarolae (Digenea: Microphallidae) adult flukes were recovered from experimental chicks at day 4-6 post-infection and their tegumental ultrastructure was observed with a scanning electron microscopy. They were pyriform in shape, and their anterior halves were concaved ventrally. The whole body surface was covered with tegumental spines, which were wide and 16-17 digitated between oral and ventral suckers. The density of spines and number of digits decreased posteriorly. The oral sucker was subterminal and the excretory pore was at the posterior end of the worm. Two ventral suckers were similar in appearance and protruded near midline of the worm. The genital atrium was dextral to the small ventral sucker. The dorsal surface was covered with tegumental spines, but the spines were sparser than on the ventral surface. On the middle portion of the dorsal surface, a small opening presumed to be the Laurer's canal was seen. From these findings, it has been confirmed that the adult G. squatarolae has unique characteristics in the surface ultrastructure.

• Parasites, Hosts and Diseases
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• v.51 no.2
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• pp.191-196
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• 2013

The echinostome metacercariae encysted in Cipangopaludina sp. snails that were purchased from a market in Vientiane Municipality, Lao PDR, were identified as Echinostoma macrorchis (Digenea: Echinostomatidae) through recovery of adult flukes after experimental infection to rats and a cat. The metacercariae were round, $113-128(121){\times}113-125(120){\mu}m$, having a thick cyst wall, a head collar armed with collar spines, and excretory granules. The adult flukes recovered from the rats and cat at day 14 and 30 post-infection, respectively, were elongated, ventrally curved, and $3.9-6.3{\times}0.7-1.1mm$ in size. The head collar was distinct, bearing 43-45 collar spines with 5 angle spines on each side. Two testes were large (as the name implies), tandem, and slightly constricted at the middle, with irregular margins. Eggs were operculated, ovoid to elliptical, and $88-95{\times}56-60{\mu}m$. In scanning electron microscopy, the head collar was prominent, with 43-45 collar spines. Scale-like tegumental spines were densely distributed on the ventral surface between the oral and ventral suckers. Sensory papillae were distributed mainly on the tegument around the 2 suckers. It is confirmed that E. macrorchis is distributed in Lao PDR using Cipangopaludina sp. snails as the second intermediate host.

• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.531-536
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• 2013

Morphological characteristics of Mesocestoides lineatus tetrathyridia collected from Chinese snakes and their adults recovered from experimental animals were studied. The tetrathyridia were detected mainly in the mesentery of 2 snake species, Agkistrodon saxatilis (25%) and Elaphe schrenckii (20%). They were 1.73 by 1.02 mm in average size and had an invaginated scolex with 4 suckers. Adult tapeworms were recovered from 2 hamsters and 1 dog, which were orally infected with 5-10 larvae each. Adults from hamsters were about 32 cm long and those from a dog were about 58 cm long. The scolex was 0.56 mm in average width with 4 suckers of 0.17 by 0.15 mm in average size. Mature proglottids measured 0.29 by 0.91 mm (av.). Ovaries and vitellaria bilobed and located in the posterior portion of proglottids. The cirrus sac was oval-shaped and located median. Testes were follicular, distributed in both lateral fields of proglottids, and 41-52 in number per proglottid. Gravid proglottids were 1.84 by 1.39 mm (av.) with a characteristic paruterine organ. Eggs were 35 by $27{\mu}m$ in average size with a hexacanth embryo. These morphological characteristics of adult worms were identical with those of M. lineatus reported previously. Therefore, it has been confirmed that the tetrathyridia detected in 2 species of Chinese snakes are the metacestodes of M. lineatus, and 2 snake species, A. saxatilis and E. schrenckii, play the role of intermediate hosts.

• Parasites, Hosts and Diseases
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• v.41 no.1
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• pp.17-25
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• 2003

The tegumental ultrastructure of juvenile and adult Himasthla alincia (Digenea: Echinostomatidae) was observed by scanning electron microscopy. One-, 5- (juveniles) and 20-day-old worms (adults) were harvested from chicks experimentally fed metacercariae from a bivalve, Mactra veneriformis. The juvenile worms were elongated and cu wed ventrally. The head crown bore 31 collar spines, arranged in a single row. The lip of the oral sucker had 12 paired, and 3 single type 1 sensory papillae, and the ventral sucker had about 25 type II sensory papillae. The anterolateral surface between the two suckers was densely packed with tegumental spines with 4-7 pointed tips. The adult worms were more elongated and filamentous, and had severe transverse folds over the whole body surface. On the head crown and two suckers, type 1 and 11 sensory papillae were more densely distributed than in the juvenile worms. Retractile brush-like spines, with 8-10 digits, were seen on the anterolateral surface, whereas claw-shaped spines, with 2-5 digits, were sparsely distributed posteriorly to the ventral sucker The cirrus characteristically protruded out, and was armed with small spines distally. The surface ultrastructure of H. alincia was shown to be unique among echinostomes, especially in the digitation of its tegumental spines, the distribution of sensory papillae and by severe folds of the tegument.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.221-229
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• 2016

Fifty-five specimens of Octopus longispadiceus, belonging to the family Octopodidae, were collected for the first time from the East Sea of Korea and identified by DNA barcoding. This species is characterized by its long right third arm and ligula, the presence of enlarged suckers in the mature male, small white spots on the mantle, head, and arms, and no cirrus above the eye. A molecular analysis of the partial cytochrome c oxidase subunit I gene showed that these specimens are all the same species and have the smallest genetic distance with O. longispadiceus (Kimura- two-parameter distance = 0.002-0.003). A new Korean name, "Bal-mun-eo" is proposed for this species.

• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.255-258
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• 1992

Two fully matured specimens were collected from the blood vessel of two fish, Tlreragra chatcogramma, which was bought at the Emun market of Seoul in May, 1985. The blood cuke has no pharynx and suckers. Its body surface was covered with minute spines forming fan-shaped groups, 15 Mm long. The intestine was H-shaped, and the ratio of esophageal length to body length was 1 : 6.1∼6.8. Irregular shaped testes were 109∼114 in number, occupying the intercecal space from cecal bifurcation to the genital pore. The present species was identified as Aporocotyle sheragrae. This is the first report of the species in Korea.

• Journal of fish pathology
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• v.15 no.3
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• pp.117-119
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• 2002

A kind of leeches, Trachelobdella sp was detected on the inside surface of the opercle of wild crucian carp, Carassius cuvieri (21.5 cm in length and 238.5 g in weight) at a reservoir for agriculture in ChungNam Province of Korea in March, 2002. Two or three round transparent spots on the opercle could be easily detected. The fish also showed severe anemia and dorsally darking in the gill lamellae. The parasites was identified as Trachelobdella sp. on the basis of morphological characteristics such as suckers, body segmentation and lateral diverticula. As the parasites fed on host blood after attaching on the inside surface of the opercle by means of the posterior sucker, they caused severe anemia and petechial haemorrhge on the gill of infested fish. Heavy infestation of the parasite resulted in dath of fish because of large amount of blood loss.