• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.208.1-208.1
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• 2016

히드라란 단세포 생물로써 강장동물에 속한다. 촉수가 많이 있으며, 그 촉수에는 독이 있다. 번식 방식으로는 출아법을 이용한다. 출아를 할 때에는 한 마리가 아닌 여러 마리의 히드라가 동시에 출아를 하기도 하며, 출아를 하고 있는 히드라는 촉수가 들어난 순간부터 먹이 섭취가 가능해진다. 이 출아법을 이용하여 번식을 하는 히드라가 DBD처리를 했을 시, 히드라 출아에 차이를 보인다면 다른 생물에게도 DBD 처리를 했을 시, 영향을 미친다고 생각하고 실험을 진행하였다. DBD(Dielectric Barrier Discharge)는 두 전극 사이에 유전체층이 있으며, 외부에서 교류 전압을 가해준다. 그러면 유전체 사이에서 방전이 발생되는데, 방전된 것을 플라즈마라고 한다. DBD라는 유전체 장벽 방전으로써 주위를 이온화 시켜 만드는 플라즈마에 유전체를 씌어 생물에게 최대한 해가 되지 않도록 만든 것이다. 유전체 장벽 방전에ROS(Reactive Oxygen Species)라는 산소와 결합된 기체들이 생성된다. DBD로 인해서 생성되는 ROS를 히드라에 처리했을 경우 히드라 출아수에 변화를 통해서 해를 끼치는 정도를 알아보고자 하였다. 그 결과 아르곤 기체에 의한 ROS로 처리한 히드라는 대조군 보다 히드라의 출아수의 변화가 있는 것으로 관찰되었고, 공기를 이용하여 방전한 DBD의 ROS로 처리한 히드라는 대조 군과 비교하여 큰 변화가 없어 보였다. 따라서 아르곤 대기압 DBD플라즈마를 이용하여 만든 ROS가 히드라에게 직접적인 영향을 준 것으로 보였다. 이 결과를 토대로 아르곤DBD를 이용한 ROS 처리는 생물에게 영향을 줄 수 있다는 것을 이 실험을 통해 간접적으로 확인해 볼 수 있었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.6
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• pp.506-513
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• 1992

Several experiments were conducted to classify the variablity of field emergence rate among the major soybean(Glycine max. (L) Merril) cultivars. The results obtained are summerized as follows. The speed of emergence is highly correlated with diameter of hypocotyl. As increasing the seed depth, emergence percentage of small seed is higher than that of large seed, and emergence of large seed at seeding depth 5cm is higher than that of small seed, at seeding depth 7cm. Emergence percentage in clay, clay : sand :(1 : 1), sand : vermiculite(1 : 1), clay : (1 : 1), sand, vermiculite are 65, 80, 84, 89, 90 and 91%, respectively. As the soil water potential was decreasing from-0.1 to-0.5 bar, emergence percentage is increasing. The highest emergence percentage was shown at -0.5 bar, and the lowest emergence percentage at -0.7 bar.

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.8-15
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• 1992

Arrowhead (Sagittaria trifolia L.), a perennial weed dominant in paddy field, is considerably difficult to control by herbicides. The investigation on the effects of environmental factors on emergence of arrowhead tuber can aid for controlling this weed. The results exmined were as follows : From the results of emergence characteristics at different levels of temperature, arrowhead tuber could germinated at 15$^{\circ}C$-40$^{\circ}C$. The optimal temperature for basal emergence was ranged from 25 to 30$^{\circ}C$. Basal emergence at 15$^{\circ}C$ and 20$^{\circ}C$ began at 56 and 12 days after tuber plantation, respectively and were later than those at the optimal temperature. At the different levels of shading, all the tested tubers could emerged. The days required for basal emergence at 25% and 50% shading plots were shorter than those at 70%, 80% and non-shading plots. The basal emergence was more effective under blue and clear films than any other phyto-selective materials. Some of arrowhead tubers could not emerged under green, red and yellow films. On the soil pH, the basal emergence was best at soil pH 6.0 and 7.0. At soil pH 4.0, 5.0 and 8.0, the required days for emergence were longer than those at soil pH 6.0 and 7.0 and some of tubers could not emerged. Arrowhead tubers more then 0.5 g showed the shorter shooting days than those less than 0.5 g. Tubers were able to emerge at water depth ranging from 0 to 20 cm. At 3 cm and 5 cm water depth, the required days for basal shooting were shorter than those at any other levels of water depth. The emergence of basals was best at molding depth of 0 cm, and the rates at 3 to 5 cm of plantation depth were decreased. At 10 cm plantation depth, the shooting rate was significantly decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.502-511
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• 1994

Investigated were the relationships between plumule elongation characteristics and seedling emergence of 98 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, Japan, etc. under proper and excess soil moisture regimes. Under excess soil moisture condition the seedling emergence and establishment rates were much lower in most of the varieties and the seedling emergence rates were delayed substantially in all varieties employed. The seedling emergence rates were lowest in dwarf and some semi-dwarf varieties showing poor plumule elongation under proper soil moisture condition. The seedling emergence and establishment rates were significantly correlated with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes, and with the lower first and second internode length under excess soil moisture condition. Average emergence duration showed significant negative correlation with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes and significant positive correlations with the first and third lower internode length. Based on the standardized partial regression analysis only the variations of mesocotyl and coleoptile length contributed significantly to the varietal difference in seedling establishment rate, and so did the variations of mesocotyl and incomplete leaf length to the varietal differences in emergence speed. In conclusion varieties with greater elongation characteristics of mesocotyl, coleoptile and incomplete leaf are desirable for higher and speedy seedling establishment in dry-direct seeding.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.368-374
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• 1985

This study was carried out to obtain the basic information for the shortening of emergence period of ginseng by treatment of growth regulators. Seedlings that removed and non-removed bud sac were treated at 10, 50 and 100ppm of GA$_3$, Kinetin and 2,4-D in early December, and investigated the characteristics of new bud emergence and growth vigor in 2-year-old ginseng. GA treatment showed the most desirable effects in shortening of emergence period of new bud, and elevating its emergence rate with increasing of the GA concentration. In addition, GA treatment especially accelerated the growth of stem and petiole length and early finished the growth of aerial parts of ginseng. On the other hand, root weights were mainly increased by formation of a lot fine roots in GA 50, 100ppm plots.

• Korean Journal of Weed Science
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• v.11 no.3
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• pp.224-228
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• 1991

This study was carried to know factors affecting emergence of major upland weeds in soil in order to get basic information on weed control methods. Firthy eight percent of weed seeds were distributed within soil surface to 10cm in soil and 2% of weed seeds were observed in 40~50cm soil layer in field. As planting depth was deeper, emergence of weeds became poor. However Capsella bursa-pastoris can emerge at soil surface. Amaranthus retroflexus, Amaranthus lividus, Porturaca oleracea, Chenopodium album, Solanum nigrum upto 3cm, Eleusine indica, Echinochloa crus-galli, Setaria viridis, Digitaria sanguinalis upto 7cm. Emergence of weeds was very poor in very acid soil but good in soil pH 5.5~6.0. However emergence of weed was not affected by pH 3.5~4.0 or above. Emergence of E. indica, C. bursa-pastoris, A. retroflexus, A. lividus, C. album, E. crus-galli, Solanum nigrum, and S. viridis was good in loam soil and P. oleranea, D. sanguinalis in sandy loam soil. Emergence of weed seeds was not affected by fertilization.

• Korean Journal of Agricultural Science
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• v.33 no.2
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• pp.149-157
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• 2006

The objective of this research was to know useful genetic characteristics for breeding program of corn. These materials were inbreds after selfing of six or eight generations and had useful genetic informations. The emergence of Danyang Waxy Corn was faster than those of other inbred lines at 2~3 days in field conditions. The plant height of Dangyang Waxy Corn was the highest at 8 days after emergence. However the plant height of New Dangjin was the shortest with 6.25cm at 8 days after emergence, the fresh weight of New Dangjin was 0.046g at 2 days after emergence but that of Dangyang was the heaviest with 0.180g. The fresh weight of 9 inbred lines had more increments in 2 days after emergence. The mean values of dry weight also showed similar trends in 9 inbred lines. The shoot dry weight of inbred lines, Dangyang and New Dangjin was 0.045g and 0.018g at 8 days after emergence, respectively. The root length of inbred line, Dangyang, was the longest with 64.4cm at 8 days after emergence. But the root length of New Dangjin was the shortest with 20.4cm at 8 days after emergence. The fresh weight of endosperm was 0.35g at 2 days after emergence and 0.26g at 8 days after emergence in Dangyang Waxy Corn, because of reduced nutrition of endosperm.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.125-129
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• 1984

Emergence and early growth of Eleocharis kuroguwai, Potamogeton distinctus, and Sagittaria pygmaea were examined at 10, 14, 18, 22, 26, and $30^{\circ}C$ of soil temperatures using soil temperature gradient bath. Eleocharis kuroguwai emerged at $14^{\circ}C$ or higher temperature and % emergence was increased as soil temperature increased up to $26^{\circ}C$ but decreased at $30^{\circ}C$. Percentage of emergence in Potamogeton distinctus was very low at $10^{\circ}C$ but most of them were emerged at $14^{\circ}C$ or above. Emergence rate was faster as soil temperature increased. Percentage of emergence in Sagittaria pygmaea was increased until 10 days after planting as soil temperature increased but final percentage of emergence was 100% at all temperature. Number of days required for 80% emergence was shortened as soil temperature increased and Eleocharis kuroguwai and Potamogenton distinctus required longer duration to emerge compared to Sagittaria pygmaea. Eleocharis kuroguwai and Potamogeton distinctus required higher accumulated soil temperature for emergence compared to Sagittaria pygmaea. Optimum soil temperature for early growth after emergence of Eleocharis kuroguwai, Potamogeton distinctus, and Sagittaria pygmaea were 26, 18-22, and 18-$26^{\circ}C$, respectively.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.183-187
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• 1992

This study was conducted to evaluate the effect of systematic herbicide application and polyethylene(PE) film mulching in direct seeded Angelica gigas Nakai. Freshly-collected-seed showed 86% of emergence rate and required 18 days of emergence duration. Cold treatment of seeds increased emergence rate by more than 90% and shortened 2 days of emergence duration. Paraquat) 1,1'-dimethyl-4,4'-bipyridylium dichloride was the most effective when applied just before emergence of A. gigas and provided 96% of emergence rate and 91% of weeding effect when applied 23 days after seeding. Soil applied herbicides used did not cause any phytotoxicity on emergence with application of 2-fold recommended rate and gave more than 90% of weeding effect. Black PE film mulching gave excellent emergence rate and weeding effect, and shortened emergence duration by 8 days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.32-36
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• 1977

Experiments were conducted to know the effects of seed bed temperatures on the sprouting of seeds and seedling growth in the phytotron and field. Sprouting of seeds were most uniform when seed bed was stored under the straw and vinyl mulching for 48 hours after seed bed temperature increased up to 3$0^{\circ}C$ by the sun. In the phytotron, optimum temperature was 32$^{\circ}C$ for sprouting and day/night temperature of 25/30 and 20/15$^{\circ}C$ for greening and hardening of seedlings, respectively. In the field, the best results were obtained under the conditions of sprouting in the seedling chamber heated by electricity and greening the hardening under the double vinyl tunnel in the upland nusery bed.