• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.26-33
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• 1977

We have studied the responce of nitrogen on the newly bred varieties, Yusin and Milyang #23, and the effects of defoliation at maturing stage on the rate of ripened grains under different nitrogen levels. The results obtained are summarized as follows : 1. Milyang #23 as well as Tongil was found to be highly nitrogen responsive variety and showed good grain maturing percentage. The number of grain per unit area affected the total yield under the high levels of nitrogen application. The variety, Yusin, was less responsive to nitrogen and had also less leaf area than other varieties under the high level of nitrogen application. Yusin also seemed to have low maturing percentage due to unbalanced ratio between photosynthetic area and size of storage. 2. The low internodes and leaf blade of Yusin and Milyang #15 were grown too much under high levels of nitrogen and these caused more lodging and less light penetration in pant canopy. 3. The effects of defoliation at maturing stage on yield was high under the high levels of nitrogen application, especially when defoliation was done early stage of maturing. The effects of defoliation appeared to be greates in Tongil than in Milyang #15.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.269-272
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• 2002

This study was carried out to investigate varietal differences on growth characteristics under the conditions of PE film-mulching and non-mulching in sesame. At maturing stage from 76 to 95 days after sowing, Yangbaeckkae, non-branching plant type, under non-mulching showed larger leaf area index (LAI) than that of film-mulching, while plant height and the number of capsules per plant were similar to those of film-mulching. LAI of Ahnsankkae, branching plant type, under non-mulching was similar to film-mulching, while plant height and the number of capsules per plant were smaller than those of film-mulching. Net assimilation rate (NAR) of two varieties under non-mulching was lower at seedling stage from 25 to 35 days after sowing but higher at flowering stage from 45 to 55 days after sowing. At maturing stage from 66 to 77 days after sowing, NAR and crop growth rate (CGR) of Yangbaeckkae under non-mulching were greater than those of film-mulching, whereas those of Ahnsankkae under non-mulching were lesser than those of film-mulching. Yield under non-mulching was decreased by 7 % in Yangbaeckkae and 33 % in Ahnsankkae compared with that of film-mulching, therefore Yangbaeckkae was more adaptable for non-mulching than Ahnsankkae. Main factors decreasing yield of Yangbaeckkae under non-mulching were small LAI, NAR, and CGR at the stage of young seedling, and small number of capsules at early maturing stage from first flowering to 20 days after first flowering.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.172-172
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• 2022

The heading response of 40 genotypes, originated from South Korea, North Korea, and northern China, was tested under the temperature and day-length conditions of thirteen major rice production area in North Korea, with aims to select adaptable varieties to the given environment and crop period for each region. To simulate regional environment, seven-day mean temperature with 10℃ daily temperature range and day-length for each region were imposed at a weekly interval in the walk-in phytotrons. Olbyeo1, Olbyeo2 and Sonbong9 originated from North Korea, Kenjiandao3 and Nongdae3 from northern China, and Joun from South Korea demonstrated the earliest heading stage depending on the regional environment. Thirty-four varieties reached heading stage within the regional safe marginal heading date (SMHD) under Haeju and Sariwon conditions while 16-17 varieties reached the stage under Wonsan, Changjon, Supung, and Yongyon environment. Some of the middle and mid-late maturing varieties originated from South Korea could reach heading stage within SMHD under the temperature and day-length conditions of Kaesong, Haeju, Sariwon, Nampo, and Pyongyang located in west-southern plain. Majority of early maturing varieties, but not middle or mid-late ones, showed heading stage within SMHD under the conditions of Singye, Anju, Kusong and Sinuiju. Only some early maturing varieties demonstrated heading stage within SMHD under Yongyon, Changjon and Wonsan environment. These results provide basic information on the varieties able to complete their normal life cycle under the regional environment in North Korea. It it further suggested that yield performance of the selected varieties for each region in this study be tested to select high yielding rice varieties adaptable to North Korean environment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.316-323
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• 1994

In order to reduce the problems from the presence of rye crop residues in maize establishment and yield, and also to improve the growth, productivity and nutritive value of rye(Seca1e cereal L.). an experiment was canied out to determine the variety effect of rye on the forage production system and the eft'ect of seeding and harvesting dates on the production and quality of rye. 'This experiment was conducted at the forage testing field of S.N.U., Suweon, from September 1986 to May 1989. Heading date of an early maturing rye variety, Wintermore. was earlier 10 days than that of a late maturing rye variety, Kodiak. A 15-days delay in the seeding dates of early and late maturing varieties of rye tended to delay the heading dates of the rye varieties for 3 and 4 days, respectively. Dry matter and in vitro digestible dry matter yields were markedly increased with earlier seeding date. Before 20 April, the DM and IVDDM yeilds of an early maturing rye variety, Winterrnore. were higher than those of a late maturing rye variety, Kodiak. However, no such a trend was found between the early and late maturing varieties of rye after 27 April. Less than 35% of ADF was recorded until the harvesting dates of 13 and 27 p r i l for early and late maturing rye varieties, respectively, but less than 46% of NDF was maintained until the harvesting drtte of 13 April for botg varieties. Based on the results obtained from this experiment. it may be concluded that the most desirable forage production from corn-rye double cropping system is to advance the seeding time of rye toward the first 10 days of September as well as harvesting time toward the first heading stage with an early maturing rye variety.

• Proceedings of the Technology Innovation Conference
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• 1997.07a
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• pp.124-159
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• 1997

This paper examines a significant example of accumulation of technology in post war Japan - the development process of the videocasstte recorder (VCR) for home use, and the dynamic evolution process of the mass market. The purpose of analyzing the Japanese home VCR industry is to clarify how and why only the Japanese makers had succeeded in developing home VCR and dominated. the global mass market and to make clear the dynamic process of industrial evolution. This study found out the following facts; 1) Japanese inter-firm interactions in the VCR have been carried out by the structure of "the competition and cooperation among the engaged players" form the initial stage, to growing, and maturing stage. 2) The process of competition and cooperation produced the revolutionary innovation through a continuous systematic development process in the R&D phase. 3) The process of competition and cooperation accelerated the speed of technological progress and the rapid growth of the industry in the growing and maturing stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.193-203
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• 2019

The aim of this study was to analyze the relationship between rice yield and climate elements in Daegu (southern plain area) and Andong (inland mountainous area) regions. Over the past 20 years, rice yield has increased in both regions. The rice yield of middle and mid-late maturing cultivars in the recent 5 years increased by about 10% and 18%, respectively, compared to that produced in the early 2000s in the Daegu region. In the Andong region, the rice yield of mid-late maturing rice cultivars in the recent 5 years was higher by about 7% than that of the early 2000s. The number of panicles per hill and grain ripening rate significantly affected rice yield in mid-late maturing cultivars. In addition, the grain weight and grain ripening rate significantly affected rice production in middle maturing cultivars grown in the Daegu region. With regard to the middle maturing cultivars, the relationship between grain weight and rice yield had a positive significant correlation in both regions. To understand the effect of climate factors on rice yield, the milled rice yield of several rice cultivars produced over the past 20 years (1999-2018) at both locations, Daegu and Andong, were evaluated. The rice yields increased owing to long sunshine duration during the grain filling stage in the Daegu region. In Andong, rising maximum temperature during the vegetative stage increased rice yield of early and mid-late maturing cultivars. Long sunshine hours increased yield of mid-late maturing cultivars in both regions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.63-69
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• 2019

Black-colored rice contains anthocyanin, which has an antioxidant function on the seed coat. Anthocyanin content is greatly affected by the cultivation environment, especially the average temperature during the ripening stage. Generally, low temperatures during the ripening stage increase anthocyanin content. To control the average temperature during ripening stage in the field, transplanting time has to be regulated. In this study, anthocyanin content variation was examined in relation to the transplanting time and the average temperature during the ripening stage. For the study, fourteen black-colored rice cultivars with different maturity types (four of early-maturing, five of medium-maturing, and five of medium-late maturing) were selected. The transplanting times used were May 20, June 5, June 20, and June 30. The field experiment was conducted in the Miryang, Kyoungsangnamdo province, Korea from 2014 to 2017. The anthocyanin content in all cultivars was higher when the transplanting time was delayed, and the highest anthocyanin content was observed in the transplanting on June 30. Variation in anthocyanin content according to the change in transplanting time is the greatest in the early maturing cultivars. The least change was observed in medium maturing cultivars. Regression analysis showed a significant correlation between temperature and anthocyanin content, but the degree of correlation was very low in the medium maturing cultivar. As a result, the optimal average temperature during the grain filling stage for increasing the anthocyanin content of black colored rice was $22{\sim}23^{\circ}C$. The rice yield increased in plants transplanted until June 20 and decreased thereafter owing to low temperature during the grain filling stage. The anthocyanin content increased with delaying the transplanting time up to June 30 but the rice yield decreased after June 20. Nevertheless, the rate of increase in anthocyanin content was higher than the rate of decrease in rice yield. As a result, the optimum transplanting time and an average temperature of grain filling stage for black-colored rice variety were June 30 and $23{\sim}24^{\circ}C$ considering both anthocyanin content and rice yield.

• Korean Journal of Animal Reproduction
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• v.11 no.3
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• pp.170-180
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• 1987

This study was undertaken to determine the effects of HCG and trout pitutary on sexual maturation and ovulation in the Korean loach, Misgurnus anguillicaudatus. Sexual maturation was observed in the fish treated with 250＋125 IU HCG within 2-4 days following injections. Total ovary weight and GSI were significantly greater in the hormone-treated fish than in the control fish. Furthermore, in the hormone-treated fish body weight increased by about 4-9 percent in 2 days. The water content of the ovulated eggs of the fish treated with 250＋125 IU HCG was also greater than that in the control. Changes in both macroscopic & microscopic appearnce of Korean loach ovaries are describled, as well as changes in the gonadosomatic index. Oocytes pass through seven cytologically changes in the relative stages. By examining these stages, it was found that oogenesis occures in two broad phases. The previtellogenic phasebegins as a new oogonia continues to arise following spawning. These rapidly develop into early perinucleolus oocytes, which in turn develop into resting stage oocytes. Most oocytes remain in this stage when they develop into late perinucleolus oocytes. The vitellogenic phase begins as these late perinucleolus oocytes become transformed into early maturing oocytes through the accumulation of yolk. The cytoplasm completely fills with yolk as oocytes reach the late maturing stage. Shortly before spawning the final hyaline stage of developing is reached. Changes in the microscopic appearances of the ovaries were well correlated with changes in both gonadosomatic index and macroscopic appearance.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.1-4
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• 2002

Eleven flavonoids, including rutin, naringin, hesperidin, neohesperidin, quercetin, naringenin, kaempferol, hesperetin, nobiletin, 3,5,6,7,8,3',4'-methoxylated flavone and tangeretin in the peel of late maturing citrus fruit species of Mucott (smith tangerine), Singamha (C. natsudidai), Sambogam (C. sulcata), Hongpalsak (C. hassaku), Seminol (Dancy tangerine) and Jawdung (C. aurantium) harvested during from August to December were analyzed with HPLC. The mobile phase consisted of water and acetonitrile with 0.5% acetic acid. Wavelength in UV detector was determined at 254 nm. Naringin and neohesperidin content in the peel of Jawdung harvested at the early stage of maturation were 34.02 mg/g and 13.68 mg/g, respectively, and it was highest among the tested citrus fruits. Hesperidin content in the peel of Mucott harvested at the earthy stage of maturation was 12.48 mg/g. Rutin content of Sambogam harvested at the early stage of maturation was 5.13 mg/g. Quercetin, naringein, kaempferol, nobiletin, 3,5,6,7,8,3',4'-methoxylated flavone flavonoids were in trace. Flavonoid contents of Singamha, Sambogam and Jawdung were high in the peel of fruits at the early stage of maturation, after which time they decreased rapidly.

• Korean Journal of Microbiology
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• v.3 no.2
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• pp.15-21
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• 1965

Using the synchronous culture method and the manometric technique, changes in respiratory activities, utilization of some organic acids (succinate, malate, lactate and acetate etc.) and its effect on glucose metabolism in Chlorella cells at different growing stages were measured. 1) Endogenous respiration of the cells was not active at growing stage and was almost constant throughout the early ripening, maturing and division stages. 2) Lactate was utilized as respiratory substrate better than other organic acids tested. Exogenous respiration of glucose was most active at growing and maturing stages and was decreased strikingly at division stage. 3) Succinate and citrate inhibited endogenous and glucose respiration of the cells throughout the all life cycle. 4) Malate and acetate were utilized in the cells at early growing and division stages better, and malate enhanced the glucose respiration while in case of acetate it was depressed. 5) Calcium ion inhibited not only permeability of respiratory substrate but endogenous respiration itself.