• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.364-367
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• 1999

Swordbean was recently introduced to Korea, and cultural technique for stable production, e.g. optimum seeding date and planting space, has not been established. This experiment was conducted to elucidate the changes of growth characteristics, yield components, and yield as affected by different seeding dates and planting spaces. Days to flowering was shortened by 4∼28 days as seeding was delayed. Stem diameter, number of pods per plant, number of seeds per plant, 100-seed weight, and seed yield tended to increase with delaying seeding up to 5 April and then to decrease with further delaying seeding. These results indicate that optimum seeding date of swordbean in unheated polyvinyl house would be early April. Although, the swordbean exhibited large increases in plant height, number of branches per plant, and stem diameter at the wider spacings, planting space could be decreased to the 60 cm plant-spacing and 30 cm row-spacing with no deleterious effect on yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.11-26
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• 1964

The studies reported herein are on the varietal differences of rice in the effects of seeding times and nursery periods on the components such as, culm length, ear length, number of ears, ear weight, straw weight, and grain/straw ratio following the first series of studies on heading date. In the present investigations, 50 rice varieties, as the preceding studies, were seeded nine times at the interval of 15 days from March 15 to July 28 in 1963. Each variety seeded at respective time was transplanted in 40 days in nursery after seeded. Reviewing the result obtained from the first series of the studies on heading date, the number of days required to heading from seeding were decreased by delaying the seeding time. Most varieties tended to decrease in the number of days from seeding to heading by the 8th planting time. Some of varieties seemed to be decreased in the number of days from seeding to heading by 9th seeding time. However most varieties were failed to show heading delaying the seeding date at the 10th seeding. The results on the effects of altering the seeding time on the components and varietal differences of the response are summarized as follows; 1) Culm length; It appeared that culm length was shortened when the number of days from seeding to heading was decreased by delaying the seeding date. The varieties which needed many days to heading were also shortened in their culm length. 2) Ear length; Ear length was also shortened when the number of days needed tocheading was decreased, by delaying the seeding time. The varieties which needed many days for heading were also shortened in their ear length, while those which headed earlier seemed to be lengthened in their ear lengths. 3) Number of ears; It was shown that the number of ears was increased with the delay of the heading date, whereas, at the 9th seeding the number of ears was decreased when delayed the heading date. 4) Ear weight; Ear weight per hill was also likely to be heavy throughout the seeding times and varieties except the 7th and 8th seedings in which it appeared to be light on the contrary. 5) Straw weight; Straw weight became heavier as delayed the seeding date throughout all the varieties and seeding dates. 6) The grain/straw ratio; The grain/straw ratio was gradually increased by the 5th seeding time, reaching the pick at 5th. An examination of the varieties at each seeding date showed that the grain/straw ratio was low from 1st to 3rd seeding and from 7th to 9th seeding, when the number of days required to heading from seeding are increased. At the 4th seeding time-which is standard seeding time-5th, and 6th seeding times the ratio was high with the delay of heading.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.3
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• pp.221-226
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• 2000

Cassia mimosoides var. nomame was grown at five seeding rates (10, 20, 30, 40 and 50 kg/ha) from March 31 to September 21, 1998 at Cheju to determine influence of seeding rate on agronomic characters, and forage yield and quality. Days to flowering increased from 126 to 129 days as seeding rate increased from 10 to 50 kg/ha. The plant height increased from 86 to 99 cm as seeding rate was increased from 10 to 30 kg/hac and then decreased to 93 cm at a rate of 50 kglha. With increasing seeding rate, stem diameter quadratically decreased and the number of branches and green leaves per plant linearly decreased but the number of withering leaves per plant linearly increased. As seeding rate increased &om 10 to 30 kg/ha, fresh forage, dry matter, crude protein, and total digestible nutrients (TDN) yield increased 'from 30.7 to 49.1, 7.5 to 12.2, 0.90 to 1.57 and 4.09 to 7.09 MTha, respectively, and then decreased with further increased seeding rates. Crude protein, ether extract, nitrogen free extract, and TDN wntent increased 12.1 to 14.2% 2.2 to 2.9%, 35.1 to 39.2%, 54.8 to 60.3% respectively, but crude fiber wntent decreased 39.8 .to 33.3% and crude ash declined 4.9 to 3.8% as seeding rate increased from 10 to 50 kgiha. The optimum seeding rate to obtain the highest TDN yield was estimated to be 36kglha. (Key words : Cassia mimosoides var. nomame, Seeding rate, Forage yield, Forage quality)

• Korean Journal of Animal Reproduction
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• v.13 no.3
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• pp.141-148
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• 1989

The effects of seeding method and optimum time for freezing embryos according to the developmental stages on embryo survival rates after rapid freezing were determined using the FDA-test. The summarized results are as follows : 1. In the rapid freezing of embryos, the sucrose added medium together with Co-seeding or non-seeding showed the FDA scores of 4.67 and 4.20, respectively, but, raffinose addition obtained FDA scores of 4.27 and 3.97. 2. The developmental stage of embryos at freezing was most critical on the survival of embryos after thawing. Higher FDA scores were obtained in the order of blastocyst stage(4.94), morula stage(3.82) and ealy stage(2.65) in sucrose added medium. The same trend was observed in the raffinose added medium with an order or 4.91, 4.47 and 2.32. 3. Microscopic study of embryo before freezing and post-thawing indicated that the embryo showed shrinkage within 5 minutes after the embryo was transfer to the freezing medium. When thawed embryo was tranfered to the dilution medium, swelling of the embryo was observed and there after it reshrank indicating the removal of cryoprotectant from the embryo. The size of the embryo recovered to the original state when it was moved into a PBS-solution.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.3
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• pp.325-331
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• 2007

This study was aimed to find out methods for preventing scale formation from the struvite treated water, and improving ammonium nitrogen removal efficiency in the application of struvite crystallization for ammonium fluoride wastewater wastement. During the struvite mystallization seeding effects varied with G.td value applied as mixing conditions in the experiment. The removal efficiency of ammonium nitrogen$(NH_4^+-N)$ and phosphorus$(PO_4^{3-}-P)$ increased over 90% in the condition of low $G{\cdot}t_d$ value. In the experiment with seeding, $G{\cdot}t_d$ value was shown to decease four times lower than the one without seeding. When adding over 2% seeding materials in the total water volume, ammonium nitrogen removal efficiencies gradually increased, of which observation was also revealed in a paired-sample T-test with 95% reliability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.513-520
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• 1991

The objective of experiment was to investigate the effects of seeding rate on forage yield and feed value, and to clarify the optimum seeding rate of rye in middle west area when cultured in paddy field. The field experiment treated with 5 levels of seeding rate was carried out at Yesan area in 1989. The plant height and the number of tillers per m' were increased but the dry matter rate was decreased as seeding rate increased. The fresh and dry weights of rye plant were increased as seeding rate increased. The highest yield was obtained from the harvest of May 15 and 25 in Yesan area. The TDN content and RFV were decreased by the increased seeding rate and delayed cutting date. The highest TDN yield was obtained from the seeding rate of 18kg/l0a and the next highest yield was obtained from the 23kg and 28kg/l0a seeding rate. The content of ENE, NEL, NEM, and NEG was decreased by the increased seeding rate and delayed cutting date. The highest ENE and NEL yields were obtained from the seeding rate of 23kg/l0a and May 15 harvest. The highest NEM and NEG yields were obtained from the seeding rates of 18kg/l0a and May 15 harvest, and of 18-28kg/l0a and May 5 harvest, respectively.

• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.144-149
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• 2002

This study was carried out to find out the effects of date and number of defoliation by different seeding date on growth and yield of perilla. Saeyuepsildlkkae was seeded from April 30 to June 30 at 20 days interval and defoliated from June 30 to Aug. 15 with different defoliation number. 1. Days to emergence, flowering, and maturing were not significantly influenced by defoliation, but those were shortened as seeding date was delayed. The interaction between defoliation and seeding date showed no significant difference. 2. Stem length, number of nodes on main stem, and weight of dry stem were not significantly affected by defoliation, but those were decreased as seeding date was delayed. 3. Yield of fresh loaves was not significantly influenced by seeding date up to May 20, but markedly decreased by the later seeding date. 4. Cluster length and number of cluster per plant were not affected by seeding date, but number of capsules per cluster was decreased from 32 to 25 and 1,000 grain weight was increased from 3.42 to 4.62g as seeding date was delayed. 5. Grain yield was not significantly affected by defoliation and seeding date up to June 10, but markedly decreased by seeding date June 30.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.999-1013
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• 2020

Weather modification research has been actively performed worldwide, but a technology that can more quantitatively prove the research effects are needed. In this study, the seeding effect, the efficiency of precipitation enhancement in weather modification experiment, was verified using the radar data. Also, the effects of seeding material on hydrometeor change was analyzed. For this, radar data, weather conditions, and numerical simulation data for diffusion were applied. First, a method to analyze the seeding effect in three steps was proposed: before seeding, during seeding, and after seeding. The proposed method was applied to three cases of weather modification experiments conducted in Gangwon-do and the West Sea regions. As a result, when there is no natural precipitation, the radar reflectivity detected in the area where precipitation change is expected was determined as the seeding effect. When natural precipitation occurs, the seeding effect was determined by excluding the effect of natural precipitation from the maximum reflectivity detected. For the application results, it was found that the precipitation intensity increased by 0.1 mm/h through the seeding effect. In addition, it was confirmed that ice crystals, supercooled water droplets, and mixed-phase precipitation were distributed in the seeding cloud. The results of these weather modification research can be used to secure water resources as well as for future study of cloud physics.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.199-207
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• 1996

This experiment was canied out to determine the effects of seeding method and seeding ratio in mixed cropping of forage rye and red clover on dry matter yield, nutritional yield and chemical characteristics of soil. The main treatment was two seeding methods(drilling and broadcasting) and the sub treatment was six seeding ratios between rye and red clover(T1; 150kg : 0 kg/ha, T2; 120 : 3, T3; 90 : 6, T4; 60 : 9, T5; 30 : 12, T6; 0 : 15). The experiment was performed at the College of Natural Science of Kon-Kuk University in Chungju in 1992. The results were summarized as follows; 1. Protein content was increased by increasing the seeding ratio of red clover, but content of NDF and ADF were decreased. 2. The seeding method did not affects significantly the dry matter yield, but broadcasting showed higher dry matter yield than drilling in the same seeding ratio. Especially, T3 of broadcasting was the highest yield of 13, 172 kg/ha The T3 of broadcasting and T4 of drilling showed hlghly crude protein yield of 1, 268 kgha and 1, 252 kg/ha, respectively. 3. Comparing the each seeding ratio of two seeding method, total nitrogen yield of shoot and root of drilling were higher than broadcasting. Especially, T2 and T4 of drilling were the highest in total nitrogen yield. 4. There were more increase in organic matter and nitrogen contents but decrease in K, Ca of soil by increasing the seeding ratio of red clover than soil before experiment. In the seeding methods, broadcasting was an effect of soil improvement.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.319-319
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• 2017

Methane is the main greenhouse gas released from rice paddy field. Methane from paddy fields accounts for 11 % of the global total methane emission. The global warming potential (GWP) of methane is 25 times more than that of carbon dioxide on a mass basis. It is well known that most effective practice to mitigate methane in paddy is related to the water management during rice growing season and the use of organic matters. This study was conducted to investigate the effects of tillage and cultivation method on methane emission in paddy. Tillage (tillage and no-tillage) and cultivation methods (transplanting and direct seeding) were combined tillage-transplanting (T-T), tillage-wet hill seeding (T-W), tillage-dry seeding (T-D) and no-till dry seeding (NT-D) to evaluate methane mitigation efficiency. Daily methane emission was decreased on seeding treatments (T-W, T-D, NT-D) than transplanting treatment (T-T). Amount of methane emission during rice growing season is highest in T-T ($411.7CH_4\;kg\;ha^{-1}y^{-1}$) and lowest in NT-D treatment (89.7). In T-W and T-D treatments, methane emissions were significantly decreased by 36 and 51 % respectively compared with T-T. Methane emissions were highly correlated with the dry weight of whole rice plant ($R^2=0.62{\sim}0.93$). T-T treatment showed highest $R^2$ (0.93) among the four treatments. Rice grain yields did not significantly differ with the tillage and cultivation methods used. These results suggest that direct seeding practice in rice production could mitigate the methane emissions without loss in grain yield.