• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.269-276
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• 2019

A semi-greenhouse experiment with field grown soybean (Glycine max L. cv Deawon, Uram, Jinpong, Soyon, Pungsangnamul, and Haewon) was performed in 2018. The experiment was aimed to investigate individual impacts of drought stress on soybean characteristic and seed yield. The three treatments were used in non-water stress (Control) during the soybean growth season, vegetative stage stress (VS), and flowering period stress (FS). Leaf number, LAI, leaf nitrogen concentration, and leaf biomass were decreased by drought at R4. In our study, the number of pods was 33.6% and 40.5% lower, respectively, in control than in VS and FS. In 100 seed weight, was 16.1% and 10.1% lower, respectively, in control than in VS and FS at R8. As a result, seed yield was 39.8% and 45.1% lower, respectively, in control than in VS and FS. Depending on the drought period, Daewon and Haewon showed a large decrease in yield, while Soyon did not change. The results of this study showed that flower and beginning pod setting stage responded more sensitively to the drought period than vegetative stage. Overall, these results demonstrate soybean seed yield formation more sensitive the during the flowing and beginning pod setting stage. We conclude that adequate water supply for pod setting stage, guaranteeing a high seed yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.262-269
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• 1988

Experiments were conducted to find out the method of reducing viviparous germination of rice seeds using growth regulators during grain filling period. Among the recommended varieties, early Japonica type showed higher rate of viviparous germination, while late Japonica type and Tongil type varieties did not show viviparous germination in field condition. Grain showed high germination ability from 30 days of grain filling period in Daeseongbyeo of Japonica type and 35 days in Taebackbyeo of Tongil type. Growth regulators, NAA, CMH and Reglone were effective for reducing viviparous germination to the two rice varieties and three treatment stages in this experiment. NAA and CMH were most effective at 100 ppm and Reglone was at 0.4-0.6% concentration. Germination rates of rice seed were not different from non-treatment when NAA CMH were treated, while Reglone lowered germination rate. NAA and CMH had no effects on grain filling rate for both varieties, which showed high grain filling rate as the non-treatment, but Reglone results low grain filling rate. Grain color was not changes when NAA was applied, while CMH and Reglone made a lot of grain to dark brown as the concentration became higher. When grain were hulled, NAA had no difference with the non-treatment whereas CMH and Reglone had lower rate of perfect brown rice when they were applied at 20-30 days after heading.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.111-117
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• 2019

It is true that early Chosun's sports meeting was influenced by Japan and the West. However, the positive nature of Chosun's sports meeting development cannot be underestimated just because it was influenced by the outsiders. It is remarkable achievement for those enlightened people at those time to promote and influenced Korean people to strengthened their nationalistic and patriotic spirit through sports meetings.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.400-406
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• 2013

This study was conducted to investigate the growth and flowering of African marigold (Tagetes erecta L.) and salvia (Salvia splendens F. Sello ex Ruem & Schult.) seedlings before and after storage under fluorescent lamps and green LED radiation conditions with different light intensities during storage. The both seedlings were kept under a storage room controlled at $8^{\circ}C$ air temperature and $40{\pm}10%$ relative humidity conditions. Light intensities were maintained at 15 and $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ during storage. In lighting treatments, dry weight of African marigold at 28 days after storage was not significantly different, and decreased approximately 29% compared to pre-storage under dark treatment. There was no significant difference in the leaf area of salvia seedlings stored under dark condition compared to before storage, but the leaf area under green light radiation with higher light intensity (treatment GH) was two times greater than before storage. The survival rate after transplanting of African marigold stored under dark condition was 10%, and days to flowering increased compared to those stored under fluorescent and green light with higher light intensity (treatment FLH, GH). Comparing to before storage, growth and flowering of the both seedlings after storage were significantly promoted by the light exposure during storage. The present experimental results show that the light intensity should be decided to maintain minimum growth during lighting storage and storage quality of the seedlings such as flowering promotion and extended blooming period after lighting treatment during storage period from the above results.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.262-270
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• 1983

The newly hatched nymphs of brown planthopper(BPH) were reared individually for two generations in test tubes, where young rice seedling was planted on agar solution, at $30^{\circ}C,\;25^{\circ}C\;and\;20^{\circ}C\;with\;95\%,\;75\%,\;65\%\;and\;35\%$ R.H. Effects of $30^{\circ}C$ on the development of BPH when compared with those of $25^{\circ}C$ are followings. Egg period, nymphal period, and adult longevity were shortened. Nymphal mortality was increased and the number of oviposited eggs was decreased. Hatchability was zero per cent because the eggs were either unfertilized or died before finishing the development. At the low temperature of $20^{\circ}C$, in comparision with $25^{\circ}C$, the developmental period of nymphs and eggs was considerably lengthened, and adult longevity was shortened, the number of oviposited eggs was decreased. The nymphal mortality was higher at high relative humidity $(above\;75\%\;RH)$ than that at low relative humidity $(under\;65\%\;RH)$. Under the condition of high relative humidities, the adult longevity was shortened, and the number of oviposited eggs was decreased.

• Animal Bioscience
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• v.34 no.4
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• pp.714-723
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• 2021

Objective: This study aimed to determine the effects of soft pellet creep feed (SPCF) on growth performance and intestinal development in piglets. Methods: A total of 18 sows and their litters of crossbred piglets (14±2 days, 3.73±0.72 kg) were assigned to one of three dietary groups receiving i) powder creep feed (PCF), ii) hard pellet creep feed (HPCF) or iii) SPCF during the pre-weaning period. After weaning, piglets were selected for continuous evaluation of the three diets on growth performance and intestinal health. Results: In the pre-weaning period, the average daily feed intake and average daily dry matter intake were significantly higher in the SPCF group than the HPCF group (p<0.05). In the post-weaning and entire experimental period, the different diets had no significant effect on growth performance. At 10 d after weaning, the serum glucose concentration was lower in the SPCF group (p<0.05) than the other groups; a higher (p<0.05) villus height and lower (p<0.05) crypt depth in the jejunum were also observed in the SPCF group than the other groups; Meanwhile, in the duodenum and jejunum, the SPCF group had a higher (p<0.05) villus height to crypt depth ratio than the other groups; Furthermore, the higher (p<0.05) threshold cycle values of lactic acid bacteria and lower (p<0.05) threshold cycle values of Clostridium, Enterobacter and Escherichia coli were also observed in the SPCF group, and the sucrase and maltase activity was higher (p<0.05) in the SPCF group than the other groups in duodenum and ileum. Conclusion: The SPCF improved pre-weaning feed intake and decreased the negative effects of weaning stress in the intestine in piglets.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.945-956
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• 2021

The effective growth of pepper seedlings relies on the growing period and tray used, which both aim to minimize seedling damage during the transplantation process. Therefore, the objective of this study was to evaluate the effect of red and green pepper seedling growth in plug and cylindrical paper pot (CPP) trays with different growth periods of the seedlings. Two different seedling growth trays were used for the two varieties of pepper seedlings in the same growing media. The pepper seedling growth rates were investigated at 15, 30, and 45 days for each of variety. Important parameters, e.g., the plant height, fresh weight for the plant and root, number of leaves, leaf length and width, and leaf chlorophyll contents, were measured. During the experiment, the CPP tray maintained uniform seedling growth as compared to the plug tray. CPP trays ensured the height of the seedling, with these results 0.84 to 1.6 times higher than those of the plug tray for all conditions, indicating the good quality of the pepper seedlings. The shoot and root weights were found to be greater with more leaves in the CPP tray seedlings for 45 days compared to the seedlings grown in the plug tray, whereas the green pepper variety showed a greater leaf ratio than the red pepper seedlings. The analysis of pepper seedling growth presented in this study will guide the selection of suitable growth trays and seedling periods for farmers when they undertake automatic pepper transplantation in the field.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.3
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• pp.176-182
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• 2007

Fishing power, which means performance of fishing vessel or catchability of fishing gear, can explain using by fishing power index(FPI) to compare fishery efficiency among uniformity types of fishery that work during the fixed period in specific fishing ground. This research analyzed on their fishing power and catchability using comparing each sampled vessels of coastal trap fishery for common octopus. The results showed that they were no difference in amount of used trap and immersed time etc. in CPUE among sampled vessels, and had no correlation of catch production due to vessel's tonnage. Most vessel's FPI estimates but 3 vessels were higher than the averaged, and showed similar fishing power in general. And then, CPUE and FPI showed that 4 to 5 tonnage vessels would be superior to another, 4 tonnage vessels had also good catchability. Therefore, we estimated that 4 tonnage vessels had the most efficiency work for coastal trap fishery for common octopus.

• Journal of the Korean Society of Food Culture
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• v.36 no.1
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• pp.76-83
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• 2021

This study investigated the effect of the addition of various levels of pig head meat (HM) as a substitute for rear leg meat (RLM) on the physico-chemical quality characteristics of non-emulsified, smoked, and cooked sausage during refrigerated storage. Sausages were prepared in four variations according to the proportion (0%, 10%, 20%, or 30%) of HM added and maintained at 4℃. Quality measurements were taken for 28 days. The sausages added with the addition of 20% and 30% HM had significantly (p<0.05) higher moisture and lower protein content compared to those without the addition of HM. The pH value during the storage period was higher (p<0.05) in the sausages to which the HM had been added than in those without HM. The sausages with 30% HM showed the lowest (p<0.05) L⁎ and b⁎ values and the highest (p<0.05) a⁎ value during the storage period. The 2-thiobarbituric acid reactive substances (TBARS) content, hardness, cohesiveness, springiness, gumminess, and chewiness of the sausages showed no significant variations with the addition of various levels of HM. These data suggest that RLM could be substituted with 30% HM because it does not negatively affect the quality of the non-emulsified sausage. However, a further study on sausages made with 100% HM instead of RLM may be needed to improve its utilization.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.188-193
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• 2022

The Korean mint (Agastache rugosa Kuntze) is used as a leaf vegetable. Therefore, it is important to improve the quality and quantity of leaves by maintaining vegetative growth. When the development of a plant is switched from vegetative to reproductive growth, leaf development may be lowered, leading to a decrease in marketability. Therefore, this study was conducted to investigate the effect of the photoperiod on the flowering characteristics and inflorescence development of the Korean mint to select an appropriate photoperiod for leaf production. The seeds were sown in 105-cell trays on 29 November 2021, and planted in each pot on 27 December 2021, when four main leaves appeared. After planting, the light/dark period was adjusted to 10/14hrs, 12/12hrs, 14/10hrs, 16/8hrs. After 19 days of planting, the first flowering occurred in 10/14hrs, which had a short photoperiod, and the 12/12hrs had 20 days for flowering, and other treatments had 21 days. In addition, it was confirmed that the Korean mint has the characteristics of facultative quantitative short-day plant, through the increase in the development of inflorescences as the light period is shorter than the dark period. As for the growth of Korean mint, the longer the photoperiod, the higher values were shown with leaf length, number of leaves, fresh weight, dry weight, and leaf area of the shoot. Therefore, it is considered that 14 h or more light period is suitable for increasing the productivity of Korean mint as a leafy vegetable.