• Journal of Aquaculture
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• v.21 no.4
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• pp.203-212
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• 2008

A nutritional demand of oyster, Crassostrea gigas larva as part of research for improving of utilization of microalgae being used for the artificial oyster seed production. The change of body growth and biochemical compositions of larvae were investigated during larvae rearing in hatchery. The larvae were cultured in 60 M/T tank and fed mixture 6 different phytoplankton species, Isochrysis galbana (30%), Cheatoceros gracilis (20%), Pavlova lutheri (20%), Phaeodactylum triconutum (10%), Nannochryis oculata (10%) and Tetraselmis tetrathele (10%). The initial feeding amount was $0.3{\times}10^4cells/mL$ at three times a day to D-shaped larva and the feeding amount had been increased 30% gradually every two day since the larvae were raising. The larvae were developed from D shape to pediveliger stage for 12 days. The daily growth of shell length and hight were $5.8{\sim}30.8\;{\mu}m$ and $8.7{\sim}31.4\;{\mu}m$, respectively and weight gains were changed from D shape to pediveliger as follow: wet weight was $0.52{\sim}15.0\;{\mu}g/larva$, dry weight was $0.2{\sim}6.5\;{\mu}g/larva$, and ash free dry weight was $0.1{\sim}8.5\;{\mu}g/larva$. The larvae growth pattern shown a logarithmic phase from D shape to umbone stage but after that stage shown a exponential growth aspect. The crude protein, crude lipid and nitrogen free extract (NFE) of larvae during rearing periods were analyzed as $6.1{\sim}10.6%$, $0.6{\sim}1.1%$ and 1.0-2.7%, respectively. And the total amino acid contents of the larvae during rearing periods were in order as glutamic acid $1.26{\sim}2.24%$, aspartic acid $0.97{\sim}1.70%$, and methionine $0.12{\sim}0.33%$. Of the total fatty acid in the analyzed larvae, the saturated fatty acid (SSAFA) was decreased from 54.3% (D shaped larvae) to 17.1 % (pediveliger) as larvae development but the total mono-unsaturated fatty acid (${\Sigma}MOFA$) and Poly-unsaturated fatty acid (${\Sigma}PUFA$) were increased from 29.9% and 7.8% to 40.6% and 45.6%, respectively. By the way the each fatty acid of the larvae were composed of palmitic acid $9.89{\sim}36.95%$, oleic acid $12.17{\sim}32.29%$, linoleic acid $1.96{\sim}33.55%$, EPA $2.17{\sim}11.58%$ and DHA $1.95{\sim}4.51%$. As a result of this study, the larvae of oyster were demanded a various nutrients for healthy growth and the feeding control, expecially after umbone stage larvae are a rapidly growing time, is very important for success of artificial seed production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.37-44
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• 1985

With a view to producing forest trees and forages, the grassland development in the forest has become an important issue in Korea. For better grassland development in the forest, a field research was carried out to investigate the effects of 3 dominant types of seed mixtures (orchardgrass type, tall fescue type, and reed canarygrass type) on the botanical composition, pasture plants composition and dry matter yield of grass-clover mixtures grown under pine trees (shading level; about 50%). As a preliminary test, 3 shading levels (o; full sunlight, 50, and 60%) were treated to compare the yield of pasture in the forest. This experiment was arranged as a randomized block design with 3 replications, and performed at the experimental field in the suburban forest of Suweon, during 1982 to 1984. The results obtained are summarized as follows: 1. As the shading level increases by 0, 50, and 6075, the dry matter yield of forage was decreased by 100 (11.13 ton/ha),81 and 76%, respectively. 2. The total ground cover and percentage of pasture plants were decreased by year, regardless of 3 different dominant types of pasture mixtures. The wild grasses and shrubs, however, tended to be increased by year. 3. Orchardgrass was found to be the only dominant grass showing 80% of all pasture plants, regardless of 3 types of pasture mixtures. But the percentage of tall fescue, reed canarygrass, Kentucky bluegrass and ladino clover were low. 4. Dry matter yield was rapidly decreased to 5075 in the second harvest year, 1984 compared with that of the first harvest year, 1983. In 1983, the yield of orchardgrass type, tall fescue type, and reed canary-grass type was 8.95, 9.05, and 7.93 ton per ha, respectively, while in 1984, the yield was 4.66, 4.57, and 4.38 ton per ha, respectively. 5. From the above results, it is suggested that tile orchardgrass dominant type of pasture mixtures is the most desirable considering forage production and botanical composition, and maintaining productivity for several years is important in the grassland under the trees.

• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.395-405
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• 2012

Lipozyme TL IM-catalyzed esterification was carried out to produce functional hard fat (structured lipid, SL) using palm stearin (PS) and hydrolysate of pomegranate seed oil (HPSO) of 1:6 molar ratio. HPSO contained conjugated linolenic acid (CLnA, about 80%). The reaction was performed at non-solvent system and solvent (n-hexane) system using Lipozyme TL IM (10% of total substrates, w/w) for 12, 24, and 72 hr in a shaking water bath ($55^{\circ}C$ and 185 rpm), respectively. SL synthesized in non-solvent system (NH-SL) and SL synthesized in n-hexane system (H-SL) were refined after deacidification, respectively. Their physicochemical properties were compared to obtain desirable functional hard fat. The content of CLnA in NH-SL increased from 34.38% to 40.63% with increasing reaction time. Similar results also observed in H-SL resulting in 36.81~45.83% of CLnA. In triacylglycerol (TAG) composition, the main molecules of LnLnLn (Ln=linolenic acid, PN=36) and the LnLnP (P=palmitic acid, PN=40) were newly synthesized in NH-SL and H-SL with increasing reaction time. After 72 hr reaction, iodine values of NH-SL (136.49) and H-SL (140.37) showed high values because of the high content of CLnA. Solid fat index (SFI) in NH-SL was higher than that in H-SL at each measured temperature. The predominant polymorphic forms of NH-SL and H-SL obtained after esterification for 72 hr were the desirable crystalline structure of the ${\beta}$' form.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.199-207
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• 1988

The study was intended to know any relations between the rice tolerance to oxyfluorfen and varietal speciation in seed protein composition or any enzymatical allelies with or without chemical treatment. Rice varieties used were Chokoto, Aichiasahi, Agabyeo, IR 3941 and Tablei as the tolerant group, and Mushakdanti, Weld Pally, HP 1033, HP 857, and HP 907 as the susceptible, respectively. Electrophoretic methods used were SDS-PAGE for seed protein, 7% PAGE for isozymes (acid phosphatase and peroxidase from rice seedling) and changes in isoenzyme activity (malate dehydrogenase, peroxidase and esterase) as affected by oxyfluorfen treatment ($10^{-4}M$) was also studied. The results are summarized as follows. -Among 19 bands separated in seed proteins, two different rice groups selected in terms of tolerance were clustered in dissimilarity. This was based on 2 facts in that G band was not present in susceptible varieties and that less activity of H, N, O, P, Q, Rand S band was shown. -Among 4 bands separated in acid phosphatase, the presence of (band and lower activity of B band was specific for tolerant varieties. For 4 minor bands separated in peroxidase, the tolerant varieties had no activity in B band and higher activity in A, C, D bands. -Time-course study of isozymes as affected by $10^{-4}M$ oxyfluorfen showed that Chokoto, the tolerant varieties, had little activity in A band and consistently higher activities in Band C bands for malate dehydrogenase. For 5 bands separated in peroxidase, B band was not found in Chokoto while A, C, D, and E bands were consistently present. Esterase was separated into about 4 bands in which Chokoto had maintained higher activities in A, C and D bands.

• Journal of Life Science
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• v.20 no.8
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• pp.1186-1192
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• 2010

Soybean [Glycine max(L.) Merr.] is an important crop, accounting for 48% of the world market in oil crops. Improvements in economic traits, such as quality and oil constituents, arethe most important objectives in soybean breeding. The objective of this study was to identify quantitative trait loci (QTLs) that control seed size and fatty acid contents in soybean. 115 $F_{2:10}$ recombinant inbred lines (RIL) developed from a cross of 'Keunolkong' and 'Iksan10' were used. Narrow-sense heritability estimates based on a plot mean on 100 seed weight, saturated fatty acid (palmitic acid + stearic acid), and oleic, linoleic, and linolenic acid content were 0.72, 0.60, 0.83, 0.77 and 0.81, respectively. The 100 seeds weight was related to seven QTLs located on chromosomes 1, 3, 8, 9, 16 and 17. Two independent QTLs for saturated fatty acid content were identified on chromosomes 17 and 19. Five independent QTLs for oleic acid content wereidentified on chromosomes7, 11, 14, 16 and 19. Five QTLs for linoleic acid content were located on chromosomes 2, 11, 14, 16 and 19. Three QTLs for linolenic acid content were located on chromosomes 8, 10 and 19. Oleic, linoleic, and linolenic acid had one major common QTL on chromosome 19. Thus, linoleic and linolenic acid content were identified as common QTLs.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.250-257
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• 1988

The study was intended to know any relations between the rice tolerance to bensulfuron and varietal speciation in seed protein composition or any enzymatical allelies with or without chemical treatment. Rice varieties used were UCP-28, Chinsurah Boro II, Fukunohama, Fadehpur-2, IR 14252-13-2-2-5 as the tolerant group, and HP 93(3) FA, HP94(9) FA, Padilabou Alumbis, KH-17854, and IR 1846-2841-1 as the susceptible, respectively. Electrophoretic methods used were SDS-PAGE for seed protein, 7% PAGE for isozymes (acid phosphatase, peroxidase, malate dehydrogenase, and esterase from rice seedling) and variation in isoenzyme profiles (malate dehydrogenase, peroxidase, and esterase) as affected by different concentrations of bensulfuron(0, $10^{-6}$, $10^{-5}$ and $3{\times}10^{-5}M$) was also studied. The results are summarized as follows. -Among 16 bands separated in seed proteins, two different rice groups selected in terms of tolerance to bensulfuron were clustered in dissimilarity, which was based on relatively larger area in whole peaks and higher activities in N, O, P bands for the tolerant group. -Among isozymes obtained from rice seedlings without chemical treatments, the following specificities were obtained. The tolerant varieties had the relatively higher activity in D band out of 4 peroxidase bands. Malate dehydrogenase was separated into 3 bands and only tolerant varieties had A band and higher activities in Band C bands. Esterase was separated into 3-4 bands with higher activities in A and B bands for tolerant varieties. There were one major band accompanied by 2-3 minor bands for acid phosphatase in which only tolerant varieties had the B band. -The effect of Bensulfuron concentration on the isozyme activities showed that the activity of C band in peroxidase was not present in tolerant varieties which was contrary to the increased activities in susceptible varieties. However, D band was gradually disappeared only in susceptible varieties as the concentration of bensulfuron was increased. For malate dehydrogenase in the susceptible varieties, major bands D, E and F kept consistantly higher activities while minor bands A, B and C disappeared sensitively. Among 5 bands of esterase separated, D band was present only in the tolerant varieties while E band only in the susceptible. The activities in A, C, E bands were sharply decreased in the susceptible varieties as the concentration of bensulfuron was increased.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.751-761
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• 2014

This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Rhododendron brachycarpum population in South Korea. Rhododendron brachycarpum were mainly distributed along the Ulleungdo and Baekdudaegan of the Korean penninsula and it's population was located at an elevation of 872m to 1466m. The Rhododendron brachycarpum population was classified into Taxus cuspidata var. latifolia dominant population, Magnolia sieboldii dominant population, Thuja koraiensis dominant population and Rhododendron brachycarpum typical population. The composition of soil properties in the same areas are as follows: organic matter, total nitrogen, available phosphorous, exchangeable $K^+$, exchangeable $Ca^{2+}$, exchangeable $Mg^{2+}$ contained, and soil pH. The capacities of these chemical properties of the soil ranged from 10.45~15.28%, 0.37~0.61%, $0.21{\sim}0.35cmol^+/kg$, $0.39{\sim}2.54cmol^+/kg$, $0.17{\sim}0.50cmol^+/kg$, $18.28{\sim}22.81cmol^+/kg$ and 4.66~5.23 respectively. The results of the correlation between communities and soil conditions of vegetation of Rhododendron brachycarpum by DCCA ordination method are as follows: Taxus cuspidata var. latifolia dominant population was found in the very steep sloped area that has low percentage of total organic matter and nitrogen than other populations. Magnolia sieboldii dominant population and Thuja koraiensis dominant population was found in the steep sloped area that has high percentage of total organic matter and nitrogen than other populations. Thuja koraiensis dominant population was found in the gentle sloped area that has high percentage of altitudinal and rock exposure. Current status of Rhododendron brachycarpum is very vulnerable with a collection of herbs constantly threatening the species' survival. Thus, concrete conservation plans to protect natural habitats should be set up as soon as possible.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.373-383
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• 2012

Soybean, C.V. Daewonkong, was planted on 25 May and 25 June in 2011, and four temperature gradient, control (ambient temperature in field plot), control + $3^{\circ}C$, control + $4^{\circ}C$, and control + $5^{\circ}C$, were artificially created by controlling the green house system. The obtained results indicated that vegetative growth of soybean plant was beneficially facilitated by planting on May (PM) than planting on June (PJ). The 100-seed weight was significantly higher in PM, and positively affected by increasing temperature, whereas the weight was reduced in control + $5^{\circ}C$ plot. Isoflavone content and fatty acid composition were analyzed to determine the effects of plating date and growth temperature. Isoflavone content was higher in PJ plot ($1479.8{\mu}g/g$) than in PM plot ($1201.8{\mu}g/g$), however, the influence of growth temperature varied with planting date. The composition of oleic acid was positively affected by increasing temperature, whereas the proportions of linoleic and linolenic acid were reduced. The numbers of node was considered as a major variable in the regression equations estimated using forward stepwise regression analysis for isoflavone content and unsaturated fatty acid under different environmental conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.89-95
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• 2008

This study was carried out to examine growth characteristics and seed qualities of 1,296 Korean soybean landraces. The range of days to flowering, and days to maturity was 38 to 83 days and 47 to 102 days, respectively. The range of growth days were 105 to 160 days, and 38% was belonged to maturity group III. The 100 seed weight was 19.5g, showing the range of 2.4 g to 40.4 g, and 19.5 g in mean. 35.3% was in the range from 13.1 g to 20.0 g, and 29.4% in the range from 20.1 g to 25.0 g. Mean contents of crude protein was 41.8%, showing the range from 32.7% to 49.2%. Mean contents of crude oil was 18.0%, showing the range from 11.8% to 22.2%. The composition of unsaturated fatty acids were from 81.8% to 94.2%, and 85.4% in mean. Sucrose contents were in the range from 1.24% to 7.91% with the mean 5.21%, and oligo-saccharide contents from 2.45% to 11.13% with the mean 8.01%. Total isoflavone contents were in the range from $278.4\;{\mu}g/g$ to $2,736.9\;{\mu}g/g$ with the mean $1,066.8\;{\mu}g/g$. Among isoflavone contents, daidzein, glycitein, and genistein contents were in the range from $48.8\;{\mu}g/g$ to $1,709.6\;{\mu}g/g$ with the mean $483.2\;{\mu}g/g$, from $0.98\;{\mu}g/g$ to $892.3\;{\mu}g/g$ with the mean $111.6\;{\mu}g/g$, and from $79.8\;{\mu}g/g$ to $1242.3\;{\mu}g/g$ with the mean $472.0\;{\mu}g/g$, respectively.

• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.24-27
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• 1993

This study was conducted to select thin-shelled and high-yielding lines in job's-tears. Two breeding lines of Suwon 3 and Suwon 6 were selected from the local collections. These two lines were tested and investigated on their characteristics under the field condition. The heading date of Suwon 3 and Suwon 6 was later one or two days, but the maturity date was one or two days earlier than that of check variety Kim-jejong, respectively. The number of grains per hill of Suwon 3, Suwon 6 was 50%, 49% greater and the milling rate was 3.8%, 5.6% higher than that of check variety, respectively. Althought 1000 grain weight of Suwon 3 and Suwon 6 was 20g lighter and the rate of ripeness was 6%, 12% lower, the raw grain yield was 22%, 20% higher than that of check variety, respectively. The thickness of seed coat of Suwon 3 and Suwon 6 was thiner and the hardness of seed coat was lower than that of check variety, therefore the milling time was decreased 12%, 7% compare to check variety, respectively. The crude protein contents of Suwon 3 and Suwon 6 was slightly higher and the amino acid composition of Suwon 6 was similar to Kimjejong, but Suwon 3 was lower than that of check variety.