• Journal of Life Science
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• v.8 no.3
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• pp.294-297
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• 1998

The objective of this study was to establish the stable cultivating method of adlay in paddy fields. The effect of soil moisture on the early of the transplanted adlay seeding was evaluated in 1996. the suitable transplanting period and the relationship between water management and leaf blight disease were tested in 1997. The critical transplanting date was June 30. rooting of transplanted adlay plants was retarded when soil moisture was saturated. However, sufficient soil moisture since one month after transplanting was required for the control of leaf blight disease and high yield of adlay.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.419-427
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• 2021

In South Korea, direct seeding of rapeseed (Brassica napus L.) is difficult during spring cultivation in early March because of the low yield production associated with late flowering and poor seed quality. To compare the period of direct sowing, the present study investigated the growth characteristics of rapeseed according to planting dates. Specifically, 35 day-old seedlings were transplanted or directly sown on four different dates (late February, early March, late March, and early April) in 2020 and 2021. As the planting date was delayed, the days to flowering of rapeseed decreased. Similarly, the plant height, seed set percentage, and seed yield of rapeseed were reduced upon delay in planting. The seed yield of rapeseed through direct seeding in late February was the highest, 2.76 ton·ha^-1. On all seeding dates, except for late February, the transplanted rapeseed produced a higher yields than the directly seeded rapeseed. The crude oil and oleic acid content, which is related to the quality of rapeseed, decreased with the delay in planting dates, and this decrease was greater, with the direct seeding of rapeseed depending on the sowing time. In the correlation analysis, the planting date was significantly and negatively correlated with the yield, crude oil content, and oleic acid content of the transplanted rapeseed, while the sowing date was negatively correlated with the plant height, silique size, yield, and seed quality of the directly seeded rapeseed. Finally, the effect of planting date on rapeseed growth was stronger in direct seeding than in transplanting. Therefore, during spring cultivation after late February to early March, transplanting, rather than direct seeding, in more advantageous in terms of seed quality and yield.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.7-12
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• 1988

This study was conducted to establish the most appropriate transplanting time which can attribute to increase of aromatic substances in tobacco variety, Hyangcho, maintaining its original aroma. The highest content of total alkaloid, total nicotine and total nitrogenous compounds were observed in the late transplanting time such as July 5, showing 4.16%, 3.83% and 3.68%, respectively. However, the petroleum ether extract was highest in the early transplanted one such as April 5, showing 5.77% and total sugar content, 12% in April 20. The content of petroleum ether extract decreased as the transplanting time delayed. The early transplanting of Hyangcho on April 20 under vinyl mulching showed the increase of fatty acid content, but the decrease of non-volatile organic acids such as malic and citric acids than those of the conventional transplanting time on March 5. The earlier transplanting time also increased the content of volatile acids such as 2,3-methylbutanoic acid and 3-methyl-pentanoic acid, which seem to be related to tobacco aroma.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.35-42
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• 1980

To establish a generation acceleration technique, two crops a year at field condition of Suweon, 10 varieties different in their spring growth habit were tested with 6 different seeding time after harvesting. These materials were harvested on June 10, 19, 79 and tested for their seed production ability at varions seeding time from July I I to August 15 with a week interval. An immatured seed germination technique and green vernalization methods were applied in cycling generations and the results obtained were summarized as follows. 1. In summer growing, seedlings establishment after transplanting was better in earlier transplanting. 2. Heading time was remarkably enhanced by earlier transplanting. Considering the results of two years early or mid of July was the suitable time to plant the second summer crop. 3. Those varieties of spring growth habit expressed little variations in plant height among the varieties. In 1978 which is referred as warm year produced plant height as tall as 8-16cm and poor crop but produced good crop with 25-65cm plant height in 1979. 4. No definit tendency in the length of spike was. observed among the cultivars but longer spike was found in winter wheat compared to the spring. 5. Number of spikes per plant was ranged from 1 to 3 regardless the transplanting time in 1979. However, more spikes per plant were produced in early or mid of July transplanting and those varieties of higher growth habit than V did not produces any spikes. 6. Higher number of grains per spike was found at earlier transplanted varieties. Therefore, it is concluded that those materials of I-IV growth habit with mid or early July transplanting would be suitable in practical sense considering their ability of seed production. 7. Two-year results indicated that wheat crop can not tolerate the temperature level higher than average 32$^{\circ}C$ C at Suweon. In this regard, the cultivation schedule was established assuming average temperature condition like the year of 1979 which was possible to grow wheats.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.2
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• pp.163-168
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• 1982

Tobacco seedling which were sown 20 days earlier than conventional, both at 4-5 and 7-8 leaf stages, were once sprayed with ethrel (0, 500, and 1,000 ppm concentrations) and transplanted simultaneously to investigate the subsequent effects. The number of leaves and days to flower were tend to decrease when seedlings were treated at an early developmental stage than at later stage. The highest yield was obtained from seedlings treated with 500 ppm of ethrel at the 4-5 leaf stage, showing 40% increment above conventional seedlings, partly due to more number and bigger size of the leaves. Finally possible mechanisms for the result were discussed.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.194-197
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• 2005

This experiment was conducted to investigate the effect of turf growth characteristics to different transplanting times. It observed that the turf growth was decreased according to delaying the transplanting time. In respect to the turf growth characteristics, it appeared that there was good for transplanting time to transplant the turf seedling before early July. With sustaining the short day length after early July, it shown that number of branch on stolen, number of nodes and Total length of stolen were apparently decreased. Especially, number of branch on stolon was decreased from 2nd up-growing branch.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.177-184
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• 2013

This study was conducted to determinate the optimum times of transplanting and harvest for enhancing the fresh leaf yield and colorant level of an indigo crop, Persicaria tinctoria H. Gross, containing the blue dye indigo. Two cultivars, Naju Local and a new cultivar, NaramBlue, were transplanted 5 times from May 30 to July 10 at an interval of 10 days, and all of experiment plots harvested on Aug. 23 in Muan, the south area of Korea. As transplanting time was delayed, fresh leaf yield were maximum at earliest transplanting (May 30) and then decreased, while Niram (blue dye extract) and indigo content of fresh leaf remained almost constant though showed a small variation. Also, two cultivars transplanted on May 23 were harvested 5 times from Jul. 20 to Sept. 20 at an interval of 15 days. As harvest time was delayed, plant height, No. of first branches, and fresh leaf yield changed increasingly, while Niram content was increased to Aug. 20 and then decreased slightly. Indigo level increased largely to Aug. 5, and then continuously decreased with more delayed harvest. These tendencies of changes in fresh leaf yield and colorant level with different transplanting and harvest times were shown similarly in both cultivars. The results indicate that early transplanting before May 30 and harvest in early August will be appropriate for improving fresh leaf yield and colorant level.

• Korean Journal of Animal Reproduction
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• v.19 no.4
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• pp.283-291
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• 1996

Transgenic animal을 응용할 수 있는 분야에서는 이식유전자의 기능을 정확하게 규명하고 이를 바탕으로 실질적인 유전적인 개량을 이루기 위해서 이식유전자의 발현을 조절할 수 있는 정교한 system이 필요하다. 유전자의 미세주입법에 의해 transgenic animal을 생산할 수 있는데 이용되고 있는 tissue-specific promoter에 의한 이식유전자의 발현조절은 필요로 하는 시기나 양 등을 인위적으로 조절하고자 하는데 한계점을 갖고 있다. 이러한 이식유전자 발현의 문제점을 극복하기 위해 효모의 recombinase나 미생물의 repressor 단백질과 이들의 binding site인 operator sequence를 이용하여 인위적으로 이식유전자의 발현을 조절할 수 있는 system이 개발되고 있다. Cre/loxP system은 site-specific recombination에 의해 DNA sequence를 제거함으로서 이식유전자의 발현을 조절할 수 있다. 이식유전자 발현의 장소와 양을 조절하기 위해서는 미생물이 이용하고 있는 repressor와 이들의 operator sequence를 적용하여 ligand binary system이 개발되었다. Lac repressor system에서는 isopropyl-$\beta$-D-thiogalactoside (IPTG)가 이식유전자 발현을 조절할 수 있는 positive regulator로서 작용하고, tetracycline-VP16 system에서는 tetracycline이나 유사물질들이 negative regulator로서 이용할 수 있다. 이러한 binary system은 transgenic animal에서 이식유전자 발현의 장소와 시기 또한 양을 효과적으로 조절하는데 적용할 수 있는 것으로 나타났다. 따라서 기존의 binary system과 함께 새로운 regulatory system의 장점을 이용하여 보다 완벽한 이식유전자의 인위적인 조절 system을 이룩함으로서 transgenic animal technology의 실용화를 앞당길 것으로 기대된다.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2004.10a
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• pp.97-97
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• 2004

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.495-508
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• 1993

This experiment was conducted to investigate the amount of natural crossing at varying isolation distance and various transplanting time in tobacco. Normal variety and male sterile line showed an average of 1. 6 and 29% natural crossing in the adjacent plantings, respectively. The natural crossing was highest in the adjacent planting, as expected, and less at the farther distance from pollinator plants. Plants transplanted in April 20th were higher in natural crossing than those of other transplanting time.