• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.111-131
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• 1975

The study has been carried out to investigate the occurrence, damage, characteristics of the pathogen, environmental conditions affecting the disease outbreak, varietal resistance, forecasting, and chemical control of bacterial leaf blight of rice in Korea since 1964. Bacterial leaf blight of rice became a major disease in Korea since 1960. A correlation was found between the annual increase of epidemics and increase of cultivation area of susceptible varieties, Jinheung, Keumnampung etc. Areal damage within the country showed that the more was at southern province, Jeonnam, Gyeongnam and western coast, and at flooded rice paddy. Yield reduction directly related with the amount of infection on upper leaves at heading stage. Fifty per cent of reduction resulted when the lesion area was more than 60 per cent. Less than 20 per cent of lesion area, however, was not affected so much on yield loss One hundred and six isolates collected from all over the country were classified as 8 strains by using 4 different bacteriophages in 1973. It was, however, only two in 1965. There were some specificities on varietal distributions among the strains such as that the Jinheung attacked mainly by strain A, B, C and I, those attack Kimmaze were A, B, H and I. Most strains were found from Tongil except D and E, whereas Akibare was only variety that attacked by strain E. Low temperature, high humidity, heavy rainfall and insutficient daylight favored the disease epidemics. Especially, typhoon and flooding at heading stage were critical factors. The earlier transplanting the more disease was resulted, and more nitrogen fertilizer application accerelated the diseased development in general. The resistance to the disease varied by growing stage of the sane plants. All of recommended varieties in Korea were susceptible to the disease except Norm No. 6 and Sirogane which moderately resistant. The pathogen, Xanthomonas oryzae, was detectable from extract of healthy seedlings that were grown in the field with an heavy infection previous year. The more bacteriophage in irigation water resulted the more disease outbreak, and the existence of more than 50 bacteriophages in 1ml. of irrigation water were necessary to initiate the disease out break. The curves representing occurrence of bacteriophages and disease outbreak were similar with 15 days interval. The survey of bacteriophage occurrence can be utilized in forecasting of the disease two weeks ahead of disease outbreak. Three applications of chemicals, Phenazin and Sangkel, in weekly intervals at the early satage of out-break depressed the symptom development, and increased yield by 20per cent. Proper period for the chemical application was just before the number of bacteriophage reaches 50 in 1ml. of irrigation water.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.2
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• pp.77-85
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• 2014

This study was conducted to examine the morphological characteristics of those Azalea Cultivars(hereinafter, Azalea Cultivars) that are mainly used for landscaping in Korea in order to prepare classification criteria. As testing materials, major Azalea Cultivars cultivated in large quantities by its producing companies were collected. Thereafter, the qualitative and quantitative characteristics of the traits of Azalea Cultivars were investigated in the way of characteristic investigation for new cultivars of azalea used by the Korea Seed and Variety Service in order to classify them and prepare the classification criteria. Since cultivar names have not been established for Azalea Cultivars for landscaping thus far, the data were compiled using the names used by cultivating companies. According to the results, Azalea Cultivars cultivated in Suncheon, Jeonnam mainly for landscaping were 10 in number; Beni, Daewang, Three, Zasanhong, Hancheol, Sancheoljuk, Gyeobsancheoljuk, Baekcheoljuk, Akado, and Seok-am. Among them, the cultivars Beni, Daewang, and Three could not be easily distinguished from each other because they are commonly called Yeongsanhong by cultivating companies and the shapes of their leaves and flowers are similar to each other. In particular, the flower color of Beni was 'bright red', that of Daewang was 'vivid purple', and that of Three was 'bright purple'. In addition, Zasanhong and Hancheol were similar to each other in shape the degree of expression of spots on the flowers and the gloss on the front side of the leaves of Hancheol were higher and stronger compared to that of Zasanhong. Sancheoljuk flowered in early April, earlier compared to other Azalea Cultivars. Gyeobsancheoljuk is an elementary species of Sancheoljuk and it had double flowers although all other traits were similar to those of Sancheoljuk. Although Baekcheoljuk was easily distinguished because it had white flowers, its leaves were similar to those of Akado the reason why these two cultivars could not be easily distinguished from each other. The cultivar Akado flowered early May later compared to other Azalea Cultivars and its flowers were relatively large in diameter as with Baekcheoljuk and Sancheoljuk. Finally, the cultivar Seok-am was easily distinguished because it had smaller leaves compared to other cultivars and it flowered late as with the cultivar Akado.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.57-66
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• 2013

The purpose of this study was to investigate the effects of shifts in sowing time on the ecological responses, growth and yields of major soybean cultivars in a southern region of South Korea. Experiments were carried out in Naju, Jeonnam Province (latitude $35^{\circ}$ 04'N, longitude $126^{\circ}$ 54'E) for three years from 2008 to 2010. The test cultivars included Saeol-kong and Tawon-kong of the summer type, Taekwang-kong and Pungsannamul-kong, and Cheongja3 of the autumn type. Sowing took place on May 15 and 30, June 15 and 30, and July 15 of each year. Of the summer type soybean cultivars, Saeol-kong showed a smaller curtailment in days from sowing to flowering, days from flowering to maturity, and days from sowing to maturity according to sowing time postponement than Tawon-kong. Of the autumn type soybean cultivars, Taekwang-kong exhibited a lower photoperiodic response in reproductive growth period than Pungsannamul-kong and Cheongja3, both of which recorded higher level photoperiodic responses in vegetative growth stages and reproductive growth periods than other test cultivars, with the former exhibiting higher levels than the latter. Most of the test cultivars tended to decrease in stem length, node numbers of the main stem, and stem diameter according to postponed sowing time, but there were no significant differences in stem length and node numbers of the main stem of the Saeol-kong cultivar. Differences in sowing times did not affect the first setting pod node order of Saeol-kong and Tawon-kong summer type cultivars of internode lengths of all of the test cultivars. All of the test cultivars tended to show decreases in pod number per plant due to postponement of sowing time except for the Saeol-kong cultivar. The variation was more prominent in small grain cultivars such as Tawon-kong and Pungsannamul-kong with the latter autumn type cultivar showing especially large variation. Yields were the greatest for the Tawon-kong, Taekwang-kong, and Pungsannamul-kong cultivars sown on May 30 and Cheongja3 sown on May 30 and June 15. There were no significant differences in the yields of Saeol-kong for different sowing times from May 30 to July 15, with the yields lowest for the batch sown on May 15.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.247-253
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• 2012

Ultrasound measures of back fat thickness (UBF), eye muscle area (UEMA) and marbling score (UMS) and carcass measures of carcass weight (CW), backfat thickness (BF), eye muscle area (EMA) and marbling score (MS) were available on 26,129 Hanwoo steers. Statistically significant differences by regions of the farms location and birth years-seasons for the steers taken ultrasound measures and their carcass measures (p<0.01) were found. Steers in Gyeonggi province showed the highest values in ultrasound measures and carcass traits except in BF compared to steers in the other provinces. Comparing between ultrasound and carcass measures, UBF was thicker in general than BF in all regions except in Daejeon city. UEMA was higher than EMA in all regions except in Gyeonggior in Jeju provinces. Especially, the difference in Jeonnam province between UEMA and EMA was $7cm^2$ while the differences between UMS and MS ranged from 0.9 to 2.26 depending on the regions of steers located. Steers born in spring showed greater ultrasound or carcass values than those born in autumn. However, carcass measures of steers born in autumn were greater than those born in spring, 2009 except MS. The pearson and residual correlations were 0.63 and 0.65 between UBF and BF, 0.31 and 0.32 between UEMA and EMA and 0.56 and 0.56 between UMS and MS, respectively.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.179-183
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• 2002

This study was carried out to investigate the influence of medium composition for in vitro mass propagation of Lycoris squamigera Max. After the disks of short stems, segments of leaf within bulb and scale were cultured on MS basal medium supplemented with various plant growth regulators, they were examined for the extent of callus formation, shoot and root regeneration. In the culture of stem disks, adventitious shoots were regenerated from the basal tissue of bulb scales, and combined medium of 1.0 mg/L 2,4-D or NAA＋2.0 mg/L BA or kinetin showed the the best response and 4∼6 shoots per explant formed. In the culture of leaf segments within bulbs, both MS medium supplemented with 1.0 mg/L NAA＋2.0 mg/L TDZ and with 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA were produced callus profusely on the base of leaf tissue and 3∼6 shoots were regenerated per explant. In the scale segments culture, calli were produced on the basal tissue on medium with 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA. The best result were shown on MS medium with 1.0 mg/L NAA＋2.0 mg/L TDZ, and 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA. Maximum number of regenerated shoots was up to 10∼12. Adventitious root formation from explants were formed profusely on MS medium with 1.0 mg/L NAA＋2.0 mg/L kinetin. The most desirable method for mass propagation of plantlets was the shoot regeneration from scale segments then subsequently subcultured on medium for rooting.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.687-696
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• 2015

Black mini tomato 'Hei-G' fruits were harvested at different stages of maturity (immature-mature green and mature-black red) and stored at different temperatures (8, 12, and $20^{\circ}C$) to investigate the quality and lycopene content during storage. Weight loss increased dramatically at higher temperature for both harvesting stages without significant differences. Firmness of immature fruits decreased below the initial level of mature fruit (8.1N) after 5, 8, and 19 days storage, when they were stored at 20, 12, and $8^{\circ}C$, respectively. Soluble solid contents of mature fruit increased at initial storage, and were higher as compared to immature fruits before deterioration at each storage temperature. Decrease in titratable acid of mature fruits depended on storage time and temperature. However, titratable acid of immature fruits showed little change during storage, and so it did not affect flavor. Hunter a value changed greatly in immature fruit stored at high temperature. Unlike ripe tomatoes, there was no significant difference in black tomato Hunter b values of immature and mature fruit at initial and 12 days storage. However, immature fruits stored at $8^{\circ}C$ did not reach full maturity and color development and ripening. High storage temperature increased lycopene production while low storage temperature blocked lycopene development. Shelf life of the immature fruits, which was evaluated by elapsed days to conventional mature stage, was 12 and 15 days when they were stored at 20 and $12^{\circ}C$, respectively. The optimum storage temperature to maintain the quality and lycopene content of mature fruits was $12^{\circ}C$. Moreover, the shelf life of mature fruits stored at $20^{\circ}C$ could reach up to 5 days.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.168-173
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• 2008

This study was conducted to determine biological characteristics of Acorus calamus L. angustatus by using aqueous, ethanol and methanol extracts from the leaves and the rhizomes of Acorus calamus L. angustatus plants. The highest total phenol contents were found in the extracts from the leaves of Acorus calamus L. angustatus ($68.4mg{\cdot}L^{-1}$) followed by rhizome ($49.3mg{\cdot}L^{-1}$). At $1,000mg{\cdot}L^{-1}$ the free radical scavenging activity of 1, 1-Diphenyl-2-picrylhydrazyl showed the highest activity in the extracts of the leaves and the rhizomes by 86.3% and 86.1%, respectively. Total flavonoid contents at $2,000mg{\cdot}L^{-1}$ extracts showed the greatest amount in the aqueous leaf extracts ($61.1mg{\cdot}L^{-1}$), and the ethanol rhizome extracts ($15.4mg{\cdot}L^{-1}$). Nitrite radical scavenging activity at $2,000mg{\cdot}L^{-1}$ was highest in the methanol extracts from leaves and rhizomes by 75.7% and 77.9%, respectively. Mushroom tyrosinase inhibition activity of leaves and rhizome from the Acorus calamus L. angustatus was very low, showing less than 1.3% regardless of the extract solvent, plant part, and concentration. These results indicated that methanol extracts from leaves exhibited higher biological activities than other extracts from rhizomes.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.333-337
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• 2009

A new malting barley variety, "Daho", was developed from the cross between "Milyang85 and Suwon335" at the Department of Rice and Winter Cereal Crop (DRWCC) NICS, in 2007. An elite line, YMB2064-B-8-2-4-1-1, was selected in 2004 and designated as "Milyang134". It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2005 to 2007 and was released with the name of "Daho", having high yielding and BaYMV resistance. The average heading and maturing dates of "Daho" were April 19 and May 27, which were 2 days later and 1 day earlier than those of "Jinyang", leading variety, at the regional adaptation yield trials (RYT), respectively. "Daho" had longer culm length (84 cm), more spikes per $m^2$ (915) and higher 1,000 grain weight (39.2 g) than those of "Jinyang" in paddy field condition. "Daho" was showed resistance to BaYMV at the regions of Naju, Jinju, and Milyang but moderately resistance at Iksan. However, the response of "Daho" to other environmental stresses was similar to "Jinyang". The yields of "Daho" at upland and paddy fields were about 5.20 MT/ha, 4.81 MT/ha, respectively, which is about 38%, 25% higher than those of "Jinyang" in the regional adaptation yield trials (RYT), respectively. It has higher grain assortment, germination capacity, water sensitivity and Kolback index but lower malt extract, diastatic power and filtration speed than those of "Jinyang".

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.328-332
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• 2009

A new malting barley variety, "Oreum", was developed from the a cross between 'Kinuyutaka' and 'Samdobori' at the Honam Agricultural Research Institute (HARI) in 2006. An elite line, YMB2077-2B-24-1-2, was selected in 2003 and designated as 'Milyang132'. It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2004 to 2006, and was released with the name of "Oreum" having high yielding and BaYMV resistance. The average heading and maturing dates of "Oreum" were April 18 and May 24, which were 2 days later than 'Jinyang', a leading variety, at RYT. "Oreum" had longer culm length (75 cm), more spikes per $m^2$ (990), and lighter 1,000 grain weight (35.2 g) than those of 'Jinyang' in paddy field conditions. It was showed resistance to BaYMV at the regions of Naju, Jinju and Milyang but moderate resistance at Iksan. However, the response to other environmental stresses of was similar to 'Jinyang' The yield potential of "Oreum" was about 5.43 MT/ha, 4.93 MT/ha in upland and paddy fields which was about 80%, 35% higher than Jinyang in the regional adaptation yield trials (RYT), respectively. It has good malting quality including high grain assortment, germination capacity ratio, water sensitivity and high the malt production and the extract and short filtration speed than those of 'Jinyang'.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.646-652
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• 2014

Data of pollution incidents which occurred in shipyards of South Korea for 10 years from 2004 to 2013 were collected and analyzed in order to propose the plans for the prevention of pollution incidents in shipyards. Total number of pollution incidents in shipyards was 103 cases over the nation of Korea for the recent 10 years and the average annual number was about 10 cases, and annual cases tended to increase from 8 cases in 2004 to 23 cases in 2010 and then to decrease to 9 cases in 2013. The location data of pollution incidents showed 32 cases in Busan metropolitan city (31%), 30 cases in Jeonnam (29%), 21 cases in Gyeongam (21%), 5 cases in Jeju (5%), 4 cases in Gangwon (4%), 4 cases in Gyeongbuk (4%), 3 cases in Chungnam (3%) and 3 cases in Incheon metropolitan city (3%). According to the data of work types of shipyards, 60 cases happened during the work of ship repair (58%), 25 cases during the work of ship breakup (24%), 10 cases in the course of ship building (10%) and 8 cases by others (8%). The data of pollutant type showed oil and oily mixtures to be 59 cases (57%), waste paint dust to be 22 cases (21%), iron dust and welding slag to be 13 cases (13%), wastes to be 4 cases (4%), waste FRP powder to be 3 cases (3%), and others to be 2 cases (2%). The plans for the prevention of pollution incidents in shipyards of Korea were proposed as follows; (1) Observance of the related laws and regulations, (2) Establishment and implementation of action plans to prevent areas dense with shipyards from causing pollution incidents, (3) Establishment and implementation of oil pollution prevention plans in shipyards, especially during the ship repair and breakup works, (4) Preparation of measures to solve civil complaints against pollution incidents in shipyards, and (5) Improvement in national management for the control of shipyards.