• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.303-303
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• 2022

The purpose of this study was to evaluate agronomic characteristics and identify the useful traits to utilize the wheat genetic resources for breeding programs by understanding the phenotypic variation among germplasm through multivariate analysis. In this study, a total of 394 wheat accessions were characterized for 15 agronomic traits using the National Agrobiodiversity Center (NAC) descriptor list, of which 31 accessions from 6 species and 363 unidentified accession (Triticum spp.) available at the NAC, Rural Development Administration (RDA), Korea. Growth characteristics such as leaf width, culm length, spike length, spikelet length, solid stemmed, days to heading, days to maturity, grain-filing period, and also seed characteristics such as width, height, area, perimeter, circle, solidity, and germination percent were studied. Among the 15 agronomic characteristics, the germination percent showed the smallest variation between resources (CV = 0.4%), and the spikelet length (CV = 66.5%) showed the highest variation. A strong positive correlation was found between seed traits such as seed height and seed area (r = 0.90), seed height and seed perimeter (r = 0.87) and seed length and width (r = 0.80). Principal component analysis (PCA) was conducted and the first five principal components comprised 76.7% of the total variance. Among the first five PCs, PCI accounted for 28.5% and PC2 for 20.0%. Wheat resources (394) were classified into four clusters based on cluster analysis, consisting of 215 resources(I), 117 resources(II), 48 resources(III), and 14 resources(IV). Among the clusters, the resources belonging to Cluster III showed the lowest seed width, height, area, and perimeter characteristics compared to other clusters. The wheat resources belonging to cluster IV had small seed width and low germination percent, but took longer to form heads and mature than resources in other clusters. These results will serve as the basis for further genetic diversity studies, and important agronomic characteristics will be used for improving wheat, including developing high-yielding and resistant varieties to biotic and abiotic stresses via breeding programs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.57-66
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• 2020

The purpose of this study was to provide information about annual variations in catch size and changes in reproductive biology in the common octopus Octopus vulgaris, a commercially important species. Samples were collected from coastal waters off Gyeongnam, Korea, by coastal trap and coastal complex fishery from February to December 2018. Octopus vulgaris have been decreasing in this region since 2007 and catch prices have been increasing. The mantle length (ML) of O. vulgaris ranged from 1.2 to 21.2 cm and body weight ranged from 42.6 to 5,537 g. The sex ratio differed significantly from what was expected, at 0.45:0.55 (P<0.05). Mature females were found from February to December, except in October and November, and males occurred from February to December, except in October. The gonadosomatic index value was higher from May to September than in other months. The total number of eggs in fecund individuals ranged from 40,280 in 578.1 g of body weight to 138,994 in 1,666.5 g of body weight. The relationship between body weight and fecundity was F=76.486BW^1.0087 (r²=0.7897). At 50% group maturity, average weight was estimated to be 636.35 g, while it was 969.30 g at 75% maturity and 1736.55 g at 97.5% maturity. This study highlights changes in catch size and reproductive biology between 2007 and 2018. These results provide basic evidence that may be used to establish regulatory policy for O. vulgaris fisheries.

• Journal of the Korean Geographical Society
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• v.38 no.3
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• pp.413-425
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• 2003

This article aims to validate empirically and verify theoretically, the applicability of the spa town life cycle model to Bath Spa located in United Kingdom. In order to test the model, the indicators of the model that associated with the rate of transportation infrastructure, the length of stay, tourist facilities, competitive resorts, advertising, tourism policy, environmental problem and the attitude of residents were examined through a comparative analysis. According to the result of this research, the indicators of 7 items excepting competitive resorts applied to Bath Spa. The competitive resorts of Bath Spa emerge at the maturity stage differing from the model that appeared at the stagnation stage. In conclusion if the new hypothesis of competitive resorts is added to the model, the model will be applied to western spa town, which has a small scale and a long history.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.27-38
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• 1996

This study was conducted to evaluate the potential of Festulolium braunii(Festuca pratensis Huds. $\times$ Loliurn mulrijZorum Lam.)as forge sources. The experiment was arranged in a split plot design with four replications from Feb. 1995. to Jan. 1996 at Hohenheim university. Main plots consisted of three forage species, Festulolirtrn braunii(Paulita), Lolium multiJomm(Lemtla), and Secale cereale(Halo) and subplots consisted of three maturity, boot, heading, and anthesis. The growth characteristics, DM yields, nutritive value, N and energy balance were observed. The heading date of Festulolium braunii was about two days earlier than that of Loliunz mrtltiflorum, farthermore Fesrulolium braunii retained higher leaf weight ratio(LWR) than other species. Festulolium brarrnii failed to show any significant differences in grass length, number of tillers, LAI, CGR, and DM accumulation when harvested at the same stage of maturity as compare with Loliurn mulriiflorutn or Setale cerede, bur the content of CP, OMD, and mineral elements and NEL value of Festulolium braunii compare to othes were slightly increased(P<0.05), while the content of NDF, ADF, and lignin decreased(P<0.05). The yield of CP was greater for Festulolium braunii than for Lolium multfimm and yields of DOM and NEL per unit area(ha) for Festulolium braunii were greater than for other species(P<0.05). The equivalent or higher DM production and nutritive value are obtained when Festulolium braunii are cut during the period from boot to anthesis stages, therefor DM intake, preference, and N and energy balance were also higher for Festulolirtm braunii compare to for other species. It could be suggested that Lolium multrfirum would be a more suitable substitute to Festuloliron braunii without decreasing forage production and quality, but the substitutive effect of Secale cereale would be difficult because of the maor differences in growth type and period compare to Fesrulolium braunii. From above the results of this experiment it appears that Festulolium braunii have a potential to provide forage sources. but funher research is needed to ascertain their potential under the climate of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.91-96
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• 1986

This study was carried out to clarify the barley grain development process under the double cropping paddy. The maximum length, width, and thickness of Baekdong were reached at 33,42, and 45 days after heading. They were not significantly reduced by 11, 7, and 5 days earlier harvesting than their above maximum develop-ing periods, respectively. Physiological maturity times were observed at about 40-46 days after heading, and the moisture contents were ranged 28-31 %. Practical maturity times were about 7 -8 days earlier than physiological ones. The beginning times of the sharp development phase of grain were delayed for two to ten days by delay of seeding times. However, the periods of the stationary and the lag development phases were about nine to ten days each and they were little changed by seeding times.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.137-141
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• 2005

The effect of cotton leaf mosaic disease on morphology, yield and fibre characteristics was examined for a susceptible cotton candidate variety CRIS-168. Plants inoculated at most susceptible growth stage (six week) under screen house showed severe mosaic symptoms. There was a significant reduction in plant height and yield. Cotton leaf mosaic disease was found to produce severe effects on plant morphology with 24.1% reduction in plant height, 25% in internode length and 37.5% in number of sympodia on main stem. However no changes were observed against number of monopodial branches per plant. Inoculated plants showed 82% decrease in yield/plant, 80% in number of boll set/ plant, 12.1% in boll weight, 12.8% in lint weight, 10.8% in seed weight, and 6.8% in seed index. Cotton leaf mosaic disease also showed effects on fibre characteristics with 0.8% decrease in GOT and 1.6% in fibre length. In contrast, uniformity ratio, fibre fineness and maturity index was increased by 20.5%, 14.4% and 0.9%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.190-194
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• 1985

Three different improved pre-release rice varieties, when transplanted at different ages of seedlings, showed that 40 day old seedlings produced the longest panicle, whereas 30 day old seedlings produced the highest culm length among treatments in all treated varieties. 40 day or older seedlings reduced the culm length remarkably mainly due to decrease in lower internodes in IET7251 and BG400-1, and due to upper as well as lower internodes in B44b-50-2-2-5-1. 30 day old seedlings produced maximum number of visible internodes. Heading as weil as maturity was delayed with increasing age of seedling.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.194-202
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• 2011

Maturation and spawning of the Shotted halibut, Eopsetta grigorjewi was investigated based on the samples captured in South Korean waters from January 2008 to December 2009. Gonadosomatic index began to increase in December, and reached maximum between January to March. After spawning it began to decrease from May. Reproductive season was estimated to January-April, with peak in February. Fecundity was proportional to the size of the female, with the clutch size varying from 170,000 eggs in the smallest female (total length, 28.9cm) to 1,300,000 eggs in the largest (total length, 41.5cm). Size at 50% sexual maturity (TL50), determined from mature females, was 28.8cm. Annual reproductive cycles of this species could be divided into six successive stages; immature stage (May-October), nucleolus stage (November-January), yolk vesicle stage (January-February), vitellogenic and ripe stage (January-April) and spent stage (April-May).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.141-146
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• 2007

We investigated the reproductive cycle of the striped eel catfish Plotosus lineatus. Specimens were sampled in the coastal waters of Sungsan and Jocheon, east of Jeju, Korea, from September 2001 to August 2002. The gonadosomatic index (GSI) in females and males were reached a maximum in June $(14.18{\pm}10.38)$ and July $(0.35{\pm}0.12)$, respectively. Based on histological observations and GSI variation, the reproductive cycle was classified into the following successive stages: in females, growing (September-April), mature (April-June), spawning (June-July), and degenerative and recovery (July-September) and in males, growing (August-December), mature (September-May), spent (April-July), and degenerative and recovery (June-August). The total length at 100% maturity exceeded 15 cm and the fecundity ranged from 525 to 1176 eggs. The fecundity was correlated positively with total length and body weight. Histological observations of the gonads suggest that this species is a spring-summer spawner with group-synchronous type oocyte development.

• The Korean Journal of Ecology
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• v.19 no.3
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• pp.217-222
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• 1996

For the ecological study on the gobioid (Favonigobius gymnauchen), samples were collected in the Korean coasts from 1983 to 1995, and the process of ovarian maturation, spawning season, settling period of young individuals and growth were investigated with the specimens collected from Kunsan coast. The ovarian egg development of this species underwent three stages; growth stage from March to April, maturity stage from May to June and spawning stage in July. All the adults died after spawning in late July. Young individuals of total length 10 mm began to live a bottom life in the tide pool of shallow waters in early and middle August. The total length of these individuals reached about 42.1 mm (mean 36.7 mm) in late November. The largest specimen examined in this study was 85.0mm of male. After that time, individuals of this species inhabited in subtidal zone from December to May of the next year. The Favonigobius gymnauchen is distributed at 17 areas of shallow waters and estuaries in the western and southern coasts of Korea.