• 한국작물학회지
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• 제53권4호
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• pp.434-439
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• 2008

The amount of salt to make seed sorting solution of the specific gravity of 1.13 was reconsidered and determined as 3.8 kg salt in 18 L water, which is lower amount than currently used. Five rice cultivars were examined. Percent germination and seedling emergence were not similar. Seedling emergence rate of Japonica varieties, Nampyungbyeo and Daerypbyeo-1 were 87% and 95% under specific gravity of 1.13, respectively. Seedling emergence rate of Tongil type variety, Dasanbyeo was as high as 67% in specific gravity of 1.06. Seedling emergence rate of waxy rice, Hwasunchalbyeo and Aranghangchalbyeo were examined. Seedling emergence rate was 94% in both cultivars in specific gravity of 1.04. Seedling emergence rate was same in specific gravity of 1.08 which is generally used for selecting seed currently. Early growth (plant height, leaf number, and dry weight) were not significantly different by specific gravity within species. In all cultivars except waxy rice, highest seedling emergence rate was observed in specific gravity of 1.13 which is currently used for selection and decreased as specific gravity is lowed. However, considering total amount of seeds in each group of specific gravity, amount of seed in lower specific gravity group is relatively small and total seedling emergence rate within variety dose not show big difference. However, if seeds with low speicific gravity are produced due to the bad grain filling condition and consequently total seed content of low specific gravity increases, results will be differnt. Reduction in total growth and yield could occur. It will be important to comply with the seed sorting criterion of 1.13 for Japonica, 1.06 for Tongil, and 1.04 for waxy rice variety to ensure the maximum rice growth and yield.

• The Korean Journal of Ecology
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• 제23권6호
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• pp.423-429
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• 2000

To understand the effects of elevated $CO_2$ concentration and temperature on seedling emergence of seven herbaceous species, the seedling emergence was monitored between November 1997 and May 1998 using a temperature gradient chamber and a $CO_2$-temperature gradient chamber. Experiment was conducted under current ambient condition (Control plot), 2$^{\circ}C$-warmed condition with ambient $CO_2$ (T2 Plot), 4$^{\circ}C$-warmed condition with ambient $CO_2$ (T4 plot). and 4$^{\circ}C$-warmed condition with 1.8 fold of ambient $CO_2$ (CT4 plot). Species tested in this study were Digitaria adscendens, Echinochloa crus-galli, Panicum bisulcatum, Setaria viridis. Oenothera biennis, Andropogon virginicus, and Imperata cylindrica. Each species often dominates in the herbaceous stage of secondary succession in Japan. The mean seedling emergence times for all species were significantly increased to 23.6 and 32.2 d in the T2 and T4 plot compared to the Control plot, respectively. The most sensitive and insensitive species in seedling emergence time in T2 plot were O. biennis and D. adscendens, respectivel.y, and those in the T4 and CT4 plot were I. cylindrica and D. adscendens, E. crus-galli and A. virginicus, respectively. All experimental species showed no significant difference in the seedling emergence rate between treatments except for O. biennis and I. cylindrica. O. biennis showed a great decrease in the seedling emergence rate from 83.3% in the Control plot to 38.0%, 14.7%, and 29.3% in the T2, T4, and CT4 plot, respectively. Elevated $CO_2$ had very little effect on the seedling emergence. From these observations, it is expected that increased temperature would greatly advance the vegetative recovery time after disturbance through the advancement of seedling emergence time.

• 한국작물학회지
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• 제49권1호
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• pp.46-51
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• 2004

The film coated snap bean (Phaseolus vulgaris) seeds with five different coating materials treated with 3% increase in seed weight were planted at sandy loam soil controlled moisture content of 18, 19, 20 and 21 %. The oxygen diffusion rate (ODR) was calculated from the different moisture content soil. The number of normal seedlings, seedling vigor, and seedling capability in field (seed vigor x dry matter weight) were observed at 9 days after planting and compared to the changes of ODR. The germination rate and ODR were sharply decreased simultaneously in the seeds planted at 21 % soil moisture content. Seedling emergence did not occur at all as the soil moisture content increased above 22 %. Hence this value should be considered as the threshold of soil moisture content for seedling emergence. An ODR value under 20% did not influence the percent emergence significantly. The certain difference observing in the emergence at the same ODR was not related clearly to the condition of soil. So it can be assumed that the limit of soil moisture content for the emergence of snap bean was approximately 20%. The value of 18% soil moisture content may be considered as the optimum for snap bean emergence. There was close relationship between the mean value of ODR in different soil moisture contents and the emergence. The germination rates of the seeds coated with the different materials were quite different when the seeds were planted at 21 % soil moisture. Dry weight of the seedlings from film coated seeds was decreased slightly, but the germination rates were not much different from the non-treated control under relatively higher soil moisture content (21 %). Major factor lowering emergence rate was oxygen stress while film coating act as a minor constraint for snap bean sown in excess soil moisture condition.

• 한국연초학회지
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• 제24권2호
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• pp.82-87
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• 2002

The purposes of this study are to investigate water content and treatment period in Solid Matrix Priming(SMP; method for enhanced rapid and uniform seedling emergence in tobacco seeds). The higher water content made the faster imbibition speed of tobacco seed. But the radicle emergence shorten the period of water equilibrium. The range of water content in SMP treatment within the limits of no radicle emergence of tobacco seed was 28∼32% to dry weight of tobacco seed. The rate of radicle emergence and seedling emergence was higher in water content 30% and 40% treatment plot than that in 50% and 60% treatment plot. But it was not different between SMP treatment and non-SMP treatment. In water content 40% during 9 days treatment, germinative energy was highest, and T50 and mean germination time(MGT) were the shortest. The germination speed was higher in SMP treatment than that in non-SMP treatment. It was not different on the germination rate between non-SMP treatment and SMP treatment.

• 한국작물학회지
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• 제48권6호
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• pp.460-464
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• 2003

본 연구는 벼 종자의 파종 후 발아, 유묘출현 및 생육 초기에 가하여지는 광질처리가 유묘 출현, 생장, 형태, 엽록소 함량 및 광합성율에 미치는 영향을 조사하여 벼의 육묘에 이용되고 있는 부직포의 색상을 전환할 필요가 있는가를 검토하고자 실시하였으며 그 결과를 요약하면 다음과 같다. 1. 파종 직후에 가하여지는 광질처리에서 유묘출현율은 조사일 모두 일미벼에서는 광질처리간 차이가 없었다. 그러나 동진벼와 대산벼에서는 원적색광 처리에서 가장 낮았으며, 청색광과 적색광간에는 차이가 거의 없었다. 2. 파종 직후에 가하여지는 광질처리로 인하여 원적색광 처리에서 초장과 엽장이 가장 짧았던 반면, 적색광은 뿌리수를 증대시켰다. 3. 파종 직후에 가하여지는 광질처리로부터 지상부 건물중은 청색광 처리에서, 뿌리의 건물중은 적색광 처리에서 가장 많았던 반면, 지상부 및 뿌리 건물중 모두 원적색광에서 가장 적었다. 4. 엽록소 함량과 광합성율 모두 품종간에는 일정한 경향이 없었으나, 광질처리에서는 이들 모두 적색광에서 가장 높고, 청색광, 원적색광 순으로 감소하였다.

• 한국자원식물학회지
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• 제11권3호
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• pp.290-295
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• 1998

Presowing treatements to seed are reasonable for elevating the seedling production efficiency. This experiment was carried out to determine the effects of $GA_3$ [0 (water) : 0.01 mM] and light qulaity (red : white) simultaneously treated before sowing on seedling emergence and growth of tobacco (Nicotiana tabacum L.) cv NC 82 and Burley 21. Red or white light was illuminated 12 hours a day while seeds of the cultivars were imbibed with either water or $GA_3$ 0.01 mM for 3 days. Seedling emergence was measured up to 20 days after sowing but morphological characters and dry weights were done 40 days. The seedling emergence rate of cv NC 82 was more affected by light quality and $GA_3$ pretreatments than that of cv Burley 21. Light quality more influenced the rate than $GA_3$ while red light or water imbibition enhanced the rates of the two cultivars compared to the other treatement. Although mean plant height and leaf number per seedling were nearly equal between the treatements, red light declined leaf area per seedling of cv Burley 21 of which seeds were imbibed in water but white light decreased the areas of both cultiars of which seeds were soaked in $GA_3$solution. Shoot dry weight was greater in cv NC 82 but less in cv Burley 21 pretreated with red light, and root dry weight showed the reverse result in white light, meaning that presowing light and $GA_3$ treatments could be changed the seedling development and growth of tobacco.

• 한국작물학회지
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• 제48권3호
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• pp.152-155
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• 2003

야생의 안동대목은 종자의 크기 및 충실도에 많은 변이를 보이고 있다. 본 연구는 약용 및 박과접목묘의 대목용으로 이용되고 있는 안동대목 종자의 크기 및 성숙 정도가 발아, 유묘 출현 및 생장에 미치는 영향을 조사하기 위하여 실시되었던 바 그 결과를 요약하면 다음과 같다. 안동대목 종자의 발아율 및 유묘출현율은 미성숙 종자에 비하여 성숙 종자에서 높았다. 그러나 종자의 크기에 따른 발아율은 성숙 종자와 미성숙 종자 모두 대립종자에 비하여 중립 또는 소립종자에서 높았던 반면, 유묘출현율은 중립종자에서 가장 높고 대립종자에서 가장 낮았다. 종자 크기와 성숙 정도가 유묘 형태 및 생장에 미치는 영향으로는 하배축 길이를 제외한 초장, 본엽수, 자엽 및 본엽의 면적은 종자 크기가 클수록 길고 많았던 반면, 종자의 성숙 정도간에는 차이가 없었다. 그러나 각 부위 및 전체 건물중은 미성숙 대립종자보다는 성숙 대립종자에서, 성숙 유무에 관계없이 종자의 크기가 클수록 많았다

• 한국작물학회지
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• 제43권3호
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• pp.194-198
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• 1998

An experiment was carried out to find out the priming effects of rice seeds, Oryza sativa L. (cv. Ilpumbyeo) on. the seedling establishment and early emergence under excess soil moisture conditions. Seeds were primed by soaking in -0.6 MPa polyethylene glycol (PEG) solution at $25^{\circ}C$ for 4 days. The primed seeds were sown in soils with various soil moistures (60, 80, 100, 120, and 140% field capacity) at 17 and $25^{\circ}C$, respectively. Germination and emergence rates, plumule height, and radicle length of primed seeds were higher than those of untreated seeds at any soil moisture and temperature examined. The time from planting to 50% germination ($T_{50}$) of primed seeds was less than that of untreated seeds by 0.9～3.7 days. Germination rate, emergence rate, plumule height, and radicle length were highest at the soil moisture of 80% field capacity among the soil moistures. Priming effects of rice seeds on germination and emergence rates were more prominent under the unfavorable soil moistures (60, 100, 120, and 140% field capacity) than those under the optimum soil moisture condition (80% field capacity). However, priming effects on seedling growth were greater at near optimum soil moisture compared with too lower or higher soil moistures. Therefore, these findings suggest that priming of rice seeds may be a useful way for better seedling establishment under the adverse soil conditions.

• 한국작물학회지
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• 제39권5호
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• pp.502-511
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• 1994

벼 건답직파에서 벼 품종들의 출아·입모 특성과 유아의 신장 특성과의 관계를 검토하고자 국내의 재래종, 육성종 및 샤레벼, 미국 직파재배품종, 이태리 품종 등 98개 품종을 토중 4.5cm에 파종하여 적습과 과습조건하에서 출아율, 입모율, 평균출아일수, 중배축장, 하위절간장, 초엽장, 불완전엽장 등을 조사하여 얻은 결과는 다음과 같다. 1. 적습조건에서 입모율은 9∼92.5%, 평균출아일수는 12∼25일 범위였고, 과습조건에서의 출아율은 0∼90%, 평균출아일수 27∼34일로 양조건 모두 품종간 변이가 매우 컸으며, 대부분의 품종은 과습조건에서 출아율이 낮아지고 출아속도가 늦어졌다. 2. 출아·입모율과 유의한 정의 상관을 보인 형질은 적습조건에서는 중배축장, 초엽장, 불완전엽장이었고, 과습조건에서는 중배축장, 제1, 2절간장, 초엽장, 불완정엽장이었다. 3. 평균발아일수는 중배축장, 초엽장, 불완전엽장과 유의한 부의 상관을 나타내었다. 4. 표준편회귀분석결과 출아·입모의 품종간 차이에 가장 유의적으로 기여하는 형질은 적습조건에서는 중배축장과 초엽장, 과습조건에서는 중배축장과 제2절간장이었다. 5. 평균출아일수의 품종간 차에 유의적으로 기여하는 형질은 적습조건에서는 중배축장, 불완전엽장으로 회귀계수는 부의 방향이었으며, 제1,2절간장은 정의 방향이었다. 과습조건에서는 중배축장만이 유의적 기여를 하였는데 회귀계수는 부의 방향이었다. 6. 본 실험의 결과로 볼 때 건답직파조건에서 출아율이 높고 출아속도가 빠른 품종을 육성하기 위해서는 중배축, 초엽 및 불완전엽의 신장이 잘되는 특성의 선발이 바람직한 것으로 사료된다.

• 한국작물학회지
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• 제47권2호
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• pp.80-84
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• 2002

In spite of simple and cheap cultivation method, water broadcast-seeded rice demonstrates uneven and unstable seedling establishment per unit land area and requires more herbicide and labor-input for weed control. Three experiments were conducted in a phytotron at 18$^{\circ}C$ to evaluate the adaptability of seed-mat mulching cultivation technologies in water seeded rice for the uniform seedling establishment and the inhibition of weed occurrence without herbicide application. Five different kinds of mat with different mesh sizes and fabric properties were tested. The emergence of rice was the highest in Lawn-mat treatment, being comparable with the control, in which seeds were sown without mat. The Lawn-mat also exhibited the lowest mat tension. Mat tension may influence the emergence of rice. And once it was soaked in water, it didn't maintain its original shape any more. The emergence rate of rice was the lowest in Safer-mat treatment. In Lawn-mat treatment, which was the most effective for rice emergence in the first study, the differences of emergence and seedling establishment of rice depending on the seeding position (upper, beneath, and between mats) treatments were negligible, while they were higher in dry seeds than in pre-germinated seeds treatment. The emergence as affected by the kinds of mat also showed the same trend when tested using barnyard grass. Depending on the kinds of mat, the inhibition effect of weeds was the greatest in Safer-mat and the poorest in Lawn-mat. These results strongly suggest the possibility that the uniform seedling establishment and weed management without chemical could be achieved simultaneously by seed-mat mulching through the combination of effective mat for the emergence of rice and another efficient mat for the inhibition of weed occurrence. This possibility was also tested in the field.