• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.794-803
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• 1997

Long line suspended culture of oysters has been started commercially in Hansan-Koje Bay since 1969. However, its Annual production has been decreased and culturing periods extended in recent years. So, we investigated environmental parameters and food organisms to identity the causes of poor fatness of oysters in Hansan-Koje Bay from February to November, 1994. As the result, the Water quality of Hansan-Koje Bay was found to be good for culture. For example, the mean concentration of COD was $1.35mg/\ell$, phosphate phosphorus was $0.30{\mu}g-at/\ell$ and dissolved inorganic nitrogen was $4.68{\mu}g-at/\ell$. However, the Hwado island and the inner part of the Hansan-Koje Bay were found to be eutrophicated due to various contaminants transported by land-based activities. But in the central pan of the Hansan-Koje Bay where the oyster farms Have been developed densely, the level of nutrient concentration was very low. During the study period, the dominant species of phytoplankton was Chaetoceros spp. with the percentage of $72.6\%\~87.8\%$ and the mean values of Chlorophyll-a concentration and phytoplankton standing crops were $2.05mg/m^3\;and\;188ind./m\ell$, respectively. The distribution of these parameters also showed similar trends those of nutrients. Especially, chlorophyll-a contents was very low with the concentration of below $0.5mg/m^3$ at central part of the Bay, Juklimpo. The fatness of oysters and the eutrophic index in this area were $18.1\%$ and 0.54, respectively. These values were lower than those of other culturing farms in the southern coastal areas in Korea. Therefore, we estimated that the insufficient food supply due to the low level of nutritional status was the major factors affecting the poor fatness of the Pacific oysters in Hansan-Koje Bay.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.265-273
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• 1986

The marine algal communities of Yonhwa-do at the southern coast of Korea were investigated in aspects to quantitative analysis of their structure and dynamics. As a result, 114 species, including 2 blue-green, 69 red, 25 brown and 18 green algae, were identified. The R/P value(2.8) is higher than that of other regions of the southern coast of Korea. Sheet and filamentous groups of the functional groups of algae showed higher composition rate in spring and summer than in autumn and winter, but coarsely branched and thick leathery groups showed an opposite tendency. Cluster analysis based on species presence suggested the existence of 5 distinct groups in spring, but 3 groups in the other seasons. The species exhibiting important value above 20 were as follows: Porphyra suborbiculata, Corallina pilulifera, Hizikia fusiforme, Sargassum thunbergii, Undaria pinnatifida, Ishige okamurai, Chondria crassicaulis, and crustose coralline algae. The coverage of algal communities composed only of crustose coralline algal complex was higher than that of other algal complex, but occurrence frequency of these two communities was indifferent. It is suggested that the occurrence in high quantity of crustose coralline algae from this area is related to grazing by herbivorous animals.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.127-132
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• 2001

This study was conducted for ten years to evaluate the effective soil management for preventing the infection of root-knot nematode in the field of continuous cultivation with oriental melon under plastic house in Songju area of kyongbuk province. The content of available phosphate, total nitrogen, organic matter, CEC, and exchangeable base in the soil increased with the increase of continuous cultivation year. Especially salt content in the soil increased form 1.2 to 4.55 mS/cm and the yield of oriental melon dramatically decreased with the continuous cultivation year. The number of root-knot nematode was 91 per $300\;cm^3$ of soil in the field of continuous cultivation for 3 years and showed slight damage on the oriental melon, but it was 518 in the field of $4{\sim}6$ years continuous cultivation and showed that 50% of plants died in August, and the yield of late season was less than 50% compared to normal plant. For the seasonal changes in infection rate of root-knot nematode on oriental melon plant, 15% of the normal plant was infected by nematode in February and increased gradually by $10{\sim}20%$ per month, 60% of plants was infected in July. The density of root-knot nematode nymph was 167 in February and increased to 1,625 in August. The infection rate of nematode was 35%, and the number of nematode was about 54 in nursery soil originated from paddy soil, upland soil, and river sand. There were no relationship between the number of nematode and available phosphate or exchangeable base in the soil of plastichouse where oriental melon plants were grown.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.667-678
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• 2005

This study was carried out to investigate the effects of addition of functional material(T1; pine needle powder, 0.4%, T2; perilla leaves powder, 0.4%, T3; green tea powder, 0.4%) on the quality characteristics of emulsion-type sausages. The samples were stored at $9{\pm}1^{\circ}C$ for 40 days and analyzed with an interval of 10 days. The pH of all emulsion-type sausages increased as storage period increased. Water holding capacity(WHC) of all treatments were slightly increased as storage period increased and rapidly decreased on 40 days of storage. In texture analysis, hardness, chewiness, gumminess and brittleness were increased with storage in all treatments group. TBARS values of T3 was lower than those of other treatments at 1 days of storage, while that was the slightly higher in T4 at 40 day of storage. The L* values was decreased as storage period increased. The a* values was highest in C, while it was the lowest in T2 and T3. The residual nitrite content of all samples were in very safe range during the whole storage period. During the storage period 40 days, the Lactobacilli spp. of C were higher($10^7$CFU/g) than those of 3 treatments. In sensory evaluation, the score of overall acceptability were higher in the order of C(5.5-6.5)>T1(4.8-6.0)>T2(4.8-5.8)>T3(4.3-4.8). In the manufacture of functional sausage containing pine needle, perilla leaves and green tea powder, further studied are needs on addition type/ratio of functional materials and the use of added spices.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.679-690
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• 2005

This study was carried out to evaluate the quality characteristics of aerobic packed pork during storage after fermentation with soy sauce, red pepper and soybean paste seasonings. The ham of pork were cut to cube($7{\time}10{\time}2$cm) and Korea traditional seasonings such as soy sauce(T1), red pepper paste(T2), soybean paste(T3) were seasoned by the proportions of meat to seasonings(1:1), respectively. The seasoned sample were fermented by fill into plastic box at $1{\pm}1^{\circ}C$ for 10 days. And then, the fermented meat from each pack was aerobic packed and stored at $1{\pm}1^{\circ}C$ for up to 28 days. The pH of T1 were significantly(P<0.05) lower compared to T2 and T3 at 1 day of storage, but were significantly(P<0.05) higher at 14 and 28 days of storage. The water-holding capacity of T1were significantly(P<0.05) higher compared to T2 and T3 at 1 and 28 days of storage. The shear force of T3 were significantly(P<0.05) lower compared to T1 during storage. The surface meat L* values of T3 were significantly(P<0.05) higher than those of T1 and T2, but a* and b* values of T2 were significantly(P<0.05) higher. The volatile basic nitrogen(VBN) of T3 were significantly(P<0.05) lower compared to T2 at 1 and 14 days of storage, but T1 were significantly(P<0.05) lower at 28 days of storage. The thiobarbituric acid reactive substances(TBARS) of T3 were significantly(P<0.05) lower compared to T1 and T2. The total plate counts of T1 were significantly(P<0.05) lower compared to T2 and T3 at 1 day of storage, but T2 were significantly(P<0.05) lower at 14 and 28 days of storage. The Escherichia coli of T1 and T3 were significantly(P<0.05) lower compared to T2 at 1 day of storage. The Lactobacilli spp. of T2 were significantly(P<0.05) lower compared to T1 and T3.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.4
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• pp.75-85
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• 2012

This study was investigated to develop an alternative medium for the cultivation of oyster mushrooms. The cultivation characteristics for major cultivated varieties of oyster mushrooms were campared with the food waste medium. In addition, water control & a gap formation of food waste is being pointed out as a problem of the medium material. Therefore, certain amounts of earthworm casting were supplied to the food waste medium to overcome the water and compaction phenomenon. This study investigated the use of the total 6 cultivars of oyster mushrooms, the Suhan(PL.1), Chiak No. 5(PL.2), Chiak No. 7(PL.3), Samgu No. 5(PL.4), Samgu No. 8(PL.5), Jangan No. 5(PL.6). In terms of medium, the optimum growth of the mycelium of the oyster mushroom was observed in the beet pulp medium but in food waste, the mycelium's growth was observed as insufficient in the bulk of cultivars. The Jangan No. 5(PL.6) was superior to other cultivars relative to the mycelium's growth. The optimum concentration of earthworm casting added the foodwaste medium was 30%. When Jangan No. 5(PL.6) was incubated in the foodwaste meidum containing 30% earthworm casting, the early days to germination were long, almost double the amount of time than that of the beet pulp medium. However, it was found that the fruit body size was larger than that of the beet pulp by up to 20.5%, and the length of the fruit body was up to 6.2% longer than that of the beet plup. The total yields increased by 60.5%. The analysis results of the oyster mushroom's nutritional contents cultured using the food waste medium, shows that the protein, vitamin A and vitamin E increased 70.6%, 2.4%, 0.8% respectively, the fat decreased by 12.6% and the oleic acid increased in a very small amount compared to that of the beet pulp medium.

• Parasites, Hosts and Diseases
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• v.31 no.2
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• pp.99-108
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• 1993

An epidemiological study of Metogonimus infection was undertaken along the upper reaches of the Nmhn River, with special consideration on the species (type) of the worms collected from humans. Eggs of Metogonimus spp. were detected from 15 (9.7%) of 154 people examined in Umsong-gun, and from each Infected person (5 cases) 6.015- 24,060 worms (mean 13,2331 were recovered after treatment with praziquantel (10 mg/kg). Eggs were also detected from 37 (48.1% of 77 people In Yongwol-gun, from whom (27 casesl 1-4,965 worms (mean 1,2151 were collected. The worm from Umsong-gun consisted of both Metagonimus Miyata type and Metagonimus takohashii, whereas those from Yongwol-gun consisted of only Metqsonimus Miyata type. When the uterine eggs of the two kinds and M. yokogawoi (obtained from people In Tamjin River basin) were morphologically compared, it was suggested that the egg size should be a good Indicator for discrlmination of the species or type. The source of human Infection was proved to be fresh water fleshes: 49 of 52 Znsco plntvpus examined, 6 of 8 Hemibcrbus loniroskis, 13 of 15 Pseunogobio esuinl:, 4 of 6 Odontobutis obscura intemfptn, and 17 of 18 Corqssiw carassiw were found Infected with Metosonimw metacercariae. From the results, it is concluded that the upper reaches of the Namhan River are endemic foci of Metogonimn Miyata type and M. takahashii.

• Research in Plant Disease
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• v.12 no.1
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• pp.32-39
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• 2006

This study has been conducted to investigate the responses of various isolates of four Colletotrichum species such as C. gloeosporioides, C acutatum, C. coccodes, and C. dematium isolated from infected tissues of several crops to fungicides such as carbendazim, carbendazim+diethofencarb, four protective fungicides, and three ergosterol biosynthesis-inhibiting (EBI) fungicides. All the isolates of C. acutatum showed $EC_{50}$ values in a range of 0.001-3.040 ${\mu}g/ml$ against carbandazim, a benzimidazole fungicide. As for the response to carbendazim, the isolates of C. gloeosporioides obtained from pepper, apple, and strawberry were clearly divided into two groups, resistant or sensitive isolates. All the resistant isolates showed $EC_{50}$ values above 1000 ${\mu}g/ml$, whereas the sensitive isolates had lower $EC_{50}$ values than 0.550 ${\mu}g/ml$. The isolates of C. gloeosporioides exhibited a negative cross resistance between carbendazim and diethofencarb (a N-phenylcarbamate fungicide), but isolates of C. acutatum did not. Toward carbendazim, C. coccodes and C. dematium isolates showed a similar response to C. acutatum isolates and the sensitive isolates of C. gioeosporioides, respectively. As for response of Protective fungicides, all the isolates of C. acutatum showed a more resistant reaction than all the isolates of C. gloeosporioides. However, there was no difference among 4 species of Colletotrichum against EBI fungicides.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.790-797
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• 2013

During pear fruit development, calyx can abscise from fruitlet following petal fall. The calyx abscission varies with pear cultivars. The presence of calyx on pear fruit makes the fruit shape calyx end protruded. In the present study, the degrees of the calyx abscission were examined in 120 Southern-type Asian pear (Pyrus pyrifolia), 52 Nothern-type Asian pear (P. ussuriensis), and 34 European pear (P. communis) cultivars, and its inheritance was investigated using cross combinations between the Southern-type Asian pear cultivars showing different degrees of calyx abscission. Majority of the cultivars produced < 10% or > 90% calyx-perpetual fruit, but the cultivars producing both calyx-perpetual and -deciduous fruit were in minor frequency. The cultivars producing < 10% calyx-perpetual fruit were in higher frequency in Southern-type Asian, Nothern-type Asian, and European pears in that order, while those producing calyx-perpetual fruit were in higher frequency in European, Nothern-type Asian, and Southern-type Asian pears in that order. In the cross between the parents producing < 10% calyx-perpetual fruit, most of the $F_1$ seedlings also produced < 10% calyx-perpetual fruit. In the cross between the parents producing > 90% calyx-perpetual fruit, on the contrary, most of the $F_1$ seedlings also produced > 90% calyx-perpetual fruit. When the paternal parent produced < 10% calyx-perpetual fruit, most of the $F_1$ seedlings also produced < 10% calyx-perpetual fruit regardless of the degree of calyx abscission in the maternal parent. When the cross was between the maternal parent producing < 10% calyx-perpetual fruit and the paternal parent showing different degrees of calyx abscission, the $F_1$ seedlings showed similar degrees of the calyx abscission to those in the paternal parent. These results suggest that the characteristics of the calyx abscission is influenced more greatly by the paternal parent than by the maternal parent, and the calyx abscission in Southern-type Asian pears is a qualitative trait which is governed by dominant gene(s).

• Food Science of Animal Resources
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• v.26 no.1
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• pp.85-91
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• 2006

This study was investigated the effect of aging at low temperature of seasoned pork with Korean traditional sauces. The samples, pork loins were cut by the shape of cube ($5{\times}15{\times}5\;cm$) and porks were seasoned with Korean tradition sauce such as soy sauce base (T1), red pepper sauce base (T2), and soybean sauce base (T3) in the same proportion of meat seasonings, respectively. The seasoned samples were stored, at $1{\pm}1^{\circ}C$ during 28 days. Surface meat color of seasoned pork was affected by the kind of sauces. Lightness of seasoned pork with soy sauce was decreased with increased in periods while red pepper sauce made it more red and soybean sauce produced a light seasoned pork, Lightness of inner meat color of seasoned pork was decreased with increased aging periods, and seasoned pork with soy sauce was lower compared to other treatments. TBARS of seasoned pork with soy sauce was lower compared to other treatments, and increased TBARS in all treatments with aging period. Total plate counts were increased with aging period, and those of seasoned pork with soy sauce were lower compared to other treatments. The microbial counts of Escherichia coli levels in all treatments was higher at the first day of aging periods. However Escherichia coli levels were decreased with increasing the aging period. Lactobacilli spp. of seasoned pork with soy sauce was not increased during aging periods, whereas other treatments were increased with aging period increased.