• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.114-115
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• 1999

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.119-120
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• 2003

우리나라에 분포하는 모자반류는 모두 28종으로 알려져 있으며 (이와 강 2002) 이 가운데 식용으로 이용되는 것은 모자반 (S. fulvellum)이 대표적이다. 모자반의 양식은 주로 서남해 지역에서 이루어지고 있으며 이들의 종묘생산은 자연에서 생식기탁이 성숙되는 4-5월경에 이루어지는데, 유배의 대량 방출을 위한 성숙 모조의 다량 확보가 어렵고 일시에 유배의 대량 방출을 유도하기 위한 성숙 유도 기법의 연구는 전무한 실정이다. 따라서 이 연구에서는 모조의 실내 배양을 통하여 유배의 대량 방출을 위한 성숙 유도 기법과 배양 조건별 엽체의 성숙 및 난방출율을 구하여 모자반의 조기채묘에 유용한 자료로 사용하고자 하였다. 또한 채묘된 발아체의 초기생장에 필요한 최적 배양 환경을 구명하고자 하였다. 모자반 모조는 전남 진도군 조도 지역의 수심 3-5m에서 채집하였으며, 채집 즉시 실험실로 운반하여 유수식 사육 수조에 수용하였다. 성숙 유도는 20$\ell$ 플라스틱 bottle을 사용하였으며, 성숙률의 정량화를 위하여 암생식기탁을 절단하여 수차례 멸균해수에서 세척후 멸균된 5cm직경의 petri dish에 멸균해수20$m\ell$와 함께 수용하여 Multi-chamber incubator에서 배양하였다. 배양조건은 5개 온도조건 (5, 10, 15, 20, $25^{\circ}C$)과16:8h의 장일 광주기 조건으로하였으며 조도는 80 $\mu$molm$^{-2}$ s$^{-1}$로 하였다. 모든 실험구는 3반복 실험하였으며 2일 간격으로 생식기탁의 생장 및 성숙 그리고 난방출 여부를 현미경하에서 측정하였다. 난이 방출된 모조로부터 유배를 분리하여 3개 조도 구간 (30, 60, 100 $\mu$molm$^{-2}$ s$^{-1}$)과 5개 온도 구간 (5, 10, 15, 20, $25^{\circ}C$)의 조합인 15개 배양 조건하에서 엽체의 길이생장을 측정하였다. 생식기탁으로부터 난의 방출은 15$^{\circ}C$와 2$0^{\circ}C$ 조건에서 배양 2일후부터 방출되기 시작하였으며, 배양 9일후 2$0^{\circ}C$ 조건에서 가장 높은 96.7$\pm$5.8%의 난방출율을 보였다. 또한 15$^{\circ}C$ 조건에서는 배양 9일후 76.7%의 난방출율을 보였다. 1$0^{\circ}C$와 $25^{\circ}C$ 조건에서는 배양 11일까지 36.7%의 난방출율을 나타내어 온도 조건에 따라 난방출 비율에 차이를 보였다. 따라서 이러한 실내 배양 결과를 다량의 모조를 조기에 성숙시키기 위해 모조 수용 수조의 수온을 자연수온보다 2~5$^{\circ}C$ 높은 12~15$^{\circ}C$ 조건으로 유지하여 15일간의 수조 관리 후 모조의 대량 유배 방출을 유도할 수 있었다. 모조 성숙을 위한 사육 수조의 수온을 2$0^{\circ}C$ 이상으로 가온할 경우 엽체의 끝녹음을 유발하였으며 가온에 따르는 가온 비용이 수반되므로 엽체의 난방출율이 70% 이상에 도달하는 15$^{\circ}C$ 조건으로 유지하는 것이 경제적일 뿐만 아니라 엽체의 건전도 유지에도 바람직하였다. 유배의 초기생장은1$0^{\circ}C$와15$^{\circ}C$의 온도조건에서 길이생장이 빠르게 증가하여, 배양 35일 후 15$^{\circ}C$와 60 $\mu$molm$^{-2}$ s$^{-1}$의 조건에서 3.9$\pm$0.2mm로 가장 높은 값을 나타내었다. 엽체의 초기 길이생장은 15$^{\circ}C$, 60 $\mu$molm$^{-2}$ -s$^{-1}$의 조도 조건에서 가장 우세하였으며, 다음으로 30과 100 $\mu$molm$^{-2}$ s$^{-1}$의 조건 순으로 나타났다. 2$0^{\circ}C$와 $25^{\circ}C$의 온도 조건에서는 각각 1.8~2.1mm로 길이생장에 있어 유의한 차이가 없는 것으로 나타났다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.57-66
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• 2013

The purpose of this study was to investigate the effects of shifts in sowing time on the ecological responses, growth and yields of major soybean cultivars in a southern region of South Korea. Experiments were carried out in Naju, Jeonnam Province (latitude $35^{\circ}$ 04'N, longitude $126^{\circ}$ 54'E) for three years from 2008 to 2010. The test cultivars included Saeol-kong and Tawon-kong of the summer type, Taekwang-kong and Pungsannamul-kong, and Cheongja3 of the autumn type. Sowing took place on May 15 and 30, June 15 and 30, and July 15 of each year. Of the summer type soybean cultivars, Saeol-kong showed a smaller curtailment in days from sowing to flowering, days from flowering to maturity, and days from sowing to maturity according to sowing time postponement than Tawon-kong. Of the autumn type soybean cultivars, Taekwang-kong exhibited a lower photoperiodic response in reproductive growth period than Pungsannamul-kong and Cheongja3, both of which recorded higher level photoperiodic responses in vegetative growth stages and reproductive growth periods than other test cultivars, with the former exhibiting higher levels than the latter. Most of the test cultivars tended to decrease in stem length, node numbers of the main stem, and stem diameter according to postponed sowing time, but there were no significant differences in stem length and node numbers of the main stem of the Saeol-kong cultivar. Differences in sowing times did not affect the first setting pod node order of Saeol-kong and Tawon-kong summer type cultivars of internode lengths of all of the test cultivars. All of the test cultivars tended to show decreases in pod number per plant due to postponement of sowing time except for the Saeol-kong cultivar. The variation was more prominent in small grain cultivars such as Tawon-kong and Pungsannamul-kong with the latter autumn type cultivar showing especially large variation. Yields were the greatest for the Tawon-kong, Taekwang-kong, and Pungsannamul-kong cultivars sown on May 30 and Cheongja3 sown on May 30 and June 15. There were no significant differences in the yields of Saeol-kong for different sowing times from May 30 to July 15, with the yields lowest for the batch sown on May 15.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.185-191
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• 1981

The purpose of this paper is to define and describe a series of growth stages for maize. cv. MTC-l (early) and Suweon No. 19 (late) that are easily identifiable by both professional agronomists and farmers. Plants were grown at a density of 60cm row with plant spacing of 15cm at six different seeding times in 1980. Leaf development indices with ten grades (LDI) were identified and defined in accordance with the development of a leaf blade. Leaf appearance rate (LAR) was ca. 3 days and it was not influenced by the variety or seeding time. The elongation of the first internode above the ground level began in a month after emergence and it corresponded to the 8th or 9th leaf stage. Internodes elongated in regular sequence of node position. The morphological change of silks related closely with the development of kernel. The duration of generative development was not influenced by varieties and seeding time but that of vegetative growth was influenced. A new scheme for the maize which was made by the developed leaves, visible nodes above ground level, morphological change of silks and development of kernel was proposed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.100-106
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• 1983

This experiment was conducted to study a cause of lodging on culm internode. The rice varieties were undergone on injuries by typo on 'Agnes' on Jeonbug Provincial in 1981 year. Long-culmed varieties had extreme lodging injury but short-culmed varieties were not serious. The lodging had weaken tolerance when culm internode was long, weight of internode per unit length was light, and culm diameter and culm wall were thin. The breaking weight of internode was light in lodging rice field. The internode length and the weight of internode per unit length between the breaking weight of internode had significant correlation. Lodging had high tolerance when the total nitrogen was low, phosphate, silica, cellulose and starch contents were high in internode. The difference of culm length and the weight of internode per unit length was high relationship with lodging.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.326-335
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• 1986

In cold water irrigation, some growth and yield were decreased by heavy application of nitrogen but in-creased by heavy application of phosphate, potassium and silicate. Among growth characters, number of spikelets per panicle and grain filling ratio were affected significantly. Cold damage in number of spikelets, spikelet sterility and degeneration of spikelet and branch could be reduced by increasing application amount of phosphate, potassium and in particular silicate. Number of spikelets per branch was closely related with number of spikelets per secondary branches. Number of abortive grains and immature grains had negative correlations with yield and could be reduced by heavy application of phosphate, potassium and silicate. Heavy nitrogen application led to high total nitrogen content and restrained the uptake of phosphate, potassium and silicate. However, adverse results were showed by heavy application of phosphate, potassium and silicate. Inorganic element contents in branches were lower than those in leaf blades, but higher than those in chaff. Branches showed little differences in inorganic element contents between heading stage and maturing stage. Inorganic element contents in branches were considered to be influenced by those in leaf blades and to affect those in chaff. Some growth characters related to source and sink, such as degeneration of branches and spike-lets, sterility ratio, ripening ratio, and yield had closer relationship with nutrient contents in branches than those in leaf blades and chaff. The results demonstrated that the rachis branch not only was a transport pathway of nutrient but also would play an important role in accumulating substances in panicles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.390-398
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• 2018

Miscanthus is a perennial energy plant that reproduces via rhizomes and has C4 metabolism. The flowering pattern of a wild type M. sacchariflorus (WTM) is affected by environmental conditions such as photoperiod and soil water status. Geodae-Uksae 1 (Geodea), which is a new M. sacchariflorus cultivar, has a lower heading rate than WMS; however the mechanism with why this happens is unknown. To confirm the effects of drought or waterlogging stresses on the growth of WTM and Geodea at the reproductive stage, we investigated variations in morphological characteristics and nutrient contents of the two Miscanthus species after four months of three water treatments. Morphological traits of the two Miscanthus species under the drought condition were similar to those under the control condition. But, the height of Geodea increased by 30% in response to the waterlogging stress. In WTM, the heading rate under the drought condition was lowest, while there was no significant difference between the waterlogging and control conditions. In the two Miscanthus species, nutrient contents, such as sucrose, total N, $P_2O_5$, K and Mg, were the highest under the drought condition, wherea Ca and Mg contents under the waterlogging condition were more than three times lower than those under the drought condition. The current study results showed that drought stress accelerated senescence and then inhibited nutrient mobilization in WTM, while waterlogging stress promoted the growth. This study is the first report to confirm that waterlogging stress promotes flowering of M. sacchariflorus.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.211-217
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• 2001

This study was conducted to evaluate the effect of Zn and Cu on physiological responses of tobacco at the different leaf ages for the purpose of phytoremediation of heavy metal contaminated field. Plant height was significantly decreased at Zn and Cu concentrations of 1.0 mM or higher. Especially, root dry weight decreased more (50% reduced) than shoot dry weight. Zn and Cu accumulation in the shoot and root was dramatically increased after 2.0 mM treatment. The accumulation pattern was different by leaf aging in that Zn accumulated more in senescence leaf and Cu accumulated more in growing leaf. The amounts of heavy metal accumulations per plant were 146,000 mg/kg for Zn and 20,500 mg/kg for Cu at 2.0 mM treatment. The proper harvesting time would be suggested as vegetative growth stage for Zn and reproductive stage for Cu. The concentrations of other inorganic ions (Mg, Mn, Fe) were decreased when Zn and Cu concentrations were increased. Cu concentration and Zn concentration of both shoot and root were decreased in Zn treatment and Cu treatment, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.121-129
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• 1987

Indonesian varieties were compared with Korean varieties on three different sowing times, each of which had three different nursery periods, at Suwon, Korea (126$^{\circ}$ 19'E and 37$^{\circ}$ 16'S). Indica-type varieties with exception of late-maturing ones had heading regardless of sowing time and nursery period. As the Korean varieties com-pared with those, the earlier sowing plots with shorter period of nursery gave better result in yields and yield components.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.318-325
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• 1986

The studies were performed to obtain the basic informations on the influence of weather condition for grain yield and yield components in barley. The data of Olbori tested in 9 sites for 12 years were used in the studies. Milled grain yield was decreased in paddy field after rice harvested comparing to the upland condition, and yield potential was differed by test sites with the most stable yield in Gyeongnam. The coefficients of variation analyzed for milled grain yield by years were 12.2-42.6% with the differences between high-yield and low-yield year. Heading date was earlier in high-yield year and southern part compared to the low-yield year and middle part of the Korean peninsular showing the negative correlation between grain yield and heading date. High-yield year showed longer in culm length, shorter in spike length, almost same in number of grains per spike, and lower in 1,000grain weight compared to the low-yield year. Correlation analyzed between number of spikes and grain yield showed positive relationship. Temperatures affected to the grain yield analyzed by high in vegitative growth stage, low in alternative growth stage, and almost same in reproductive growth stage in high-yield year comparing to the low-yield year, however no remarkable differences of temperatures affected were detected in over wintering stage between high-yield and low-yield year. Precipitation amount in high-yield year was lesser in sowing time, more in seedling time, and lesser in over wintering time than those of the low-yield year. Correlation between rainfall amount in the early of April and grain yield showed significant negative correlation with the remarkable affects to the grain yield. Sunshine hours in high-yield year were longer in sowing time, shorter in over wintering time, and after the over wintering time to harvesting time was longer than those of the low-yie-ld year.