• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.320-327
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• 1990

Experiments were conducted to investigate the method to raise seedling establishment rate and the optimum seeding dates and rates in direct seeding culture using transplanter under submerged field condition in Chuncheon area during 1986 to 1988. Direct seeding on submerged field using transplanting machine after sowing on seedling growing box contained with paddy or upland soil was possible. Higher rate of seedling establishment was obtained in case of sowing sprouted seed and intermittent irrigation after sowing. Seedling establishment rate was higher both in April 30 or May 10 seeding plot. Minimum daily average air and soil temperature to ensure more than 70 percent seedling establishment was 14.8$^{\circ}C$ and 16.3$^{\circ}C$ respectively. Optimum sowing date in the direct sowing was early May and optimum sowing rate was 200g per box, 6kg per l0a. In this case rice grain yield was 481kg per l0a and this is almost same yield level compared hand and machine transplanting.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.124-131
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• 1992

Not only reducing the carry-over effects of quinclorac [3, 7-dichloro-8-quinoline carboxylic acid] used in paddy field to some following vegetable crops but also rationalizing agro-ecology conservation and farm economy, the reducing feasibility of application rates by various cropping patterns and application timing after rice seeding and transplanting. Four cropping patterns namely dry direct seeding(DDS), flooded direct seed(FDS), transplanting of 8 days old early seedlings(EST) and 25 days old machinery seedling(MST) were experimented with 7 application timings as 0, 5, 10, 15, 20, 25, 30 days after seeding/transplanting and 9 levels of application rates as 0, 75, 150, 225, 300, 375, 450, 525, and 600g ai/ha of the chemical, respectively. Within the maximum permitted limit of rice phytotoxicity, the minimum application rate of quinclorac to complete control of Echinochloa crus-galli as influenced by various cropping patterns with application timing could be evaluated as follows : A. Dry direct seeding : The minimized application rate at application timing upto 10 days after seeding (DAS) was counted 150g ai/ha, and delaying upto 15-30 DAS, the rates were increased upto 225-525g ai/ha. B. Flooded direct seeding and transplanting : The application rates were minimized 75g ai/ha at application timing upto 10 days after seeding/transplanting(DAS/T), 150g ai/haupto 15 DAS/T, and 225g ai/ha at later than 20 DAS/T, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.85-90
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• 2015

The objective of this study was comparison of seed yields according to different seeding rates, seeding time and application of chemical fertilizations in Yanji region of China. The experiment was conducted on commercial farmland at Yanji region in 2013. All the experimental fields were designed following randomized block design with 3 replicates. The plant spacing was applied as $65{\times}1cm$ distance. To check the effect of seeding rate, two different seeding rate, 0.2 kg/0.1ha and 0.5 kg/0.1ha were applied. The higher seed yield was observed in low seeding rate (0.2 kg/0.1ha). The application of fertilizer (mixture of N and P) showed different results following different experimental fields. However, there were little positive effects following fertilizer application into commercial farmland. When we compare seed yields between two different seeding dates, $4^{th}$ May and $29^{th}$ May, the earlier seeding date ($4^{th}$ May) showed higher seed yields. In considering these results, low seeding rate and early seeding time is important for getting high camelina seed yields.

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.62-66
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• 2007

This study was carried out to develop the stable plug seedling production for hydroponics of spinaches by various nursery media, plug tray size and seed number per plug tray cell. When plant grown in various nursery media, the seeding stand rate was shown in order of granular rockwool with good water retention, granular rockwool>granular rockwool mixed with pearlite>cocopeat>pearlite>poly urethane foame. Thus, poly urethane foame indicated the lower seedling stand rate. There was no difference in growth of the seedlings md the seeding stand rate by the plug tray size, and no significant difference in the plant height and the number of leaves among the seed number per plug tray cell. But, leaf area of plant in 2 grains seeding per cell was $113.0cm^2$, was wider in compared with 5 grains seeding of which leaf area was $88.0cm^2$. Accordingly, the leaf area per plant decreased as more and more the number of seeds per plug tray cell increased. The fresh weight of a plant per plug tray cell was the heaviest with 12.5g in the 2 grains, and the total fresh weight of plants per cell was 33.9g in 4 grains seeding, thus it tended to was bigger compared with other treatments. Consequently, given that the number of seeds per cell was decreased, the fresh weight of a plant increased. On the other hand, the total fresh weight per cell showed a tendency to be reducing as more and more the number of seeds per plug tray cell decreased. The yield in the 4 grains seeding was increased by 46% as $14,910kg{\cdot}ha^{-1}$ in compared with the yield in 2 grains seeding as $10,200kg{\cdot}ha^{-1}$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.2
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• pp.75-80
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• 2001

This study was conducted to identify the optimum proper nitrogen (N) application rate for tillering in ridge direct seeding on dry paddy of rice culture. During 1998, a series of experiments was carried out at paddy field (Chonbuk series) of the National Honam Agricultural Experiment Station, RDA using Dongjinbyeo. Leaf area index and top dry weight increased with higher N levels, especially in the 100 kg/ha seeding rate compared with the 60 kg/ha seeding rate. N use efficiency increased at increased by 50~75% of the N topdressing rate at tillering. Heading date, ripened grain rate, and 1,000-grain weight of brown rice did not vary among the rate of topdressing for tillering and seeding rates. The highest grain number per unit area was at the level of increased by 75% in N topdressing at tillering stage. Milled rice yield increased 5% at the 60 kg/ha seeding rate and increased 16~17% at the 100 kg/ha seeding rate at increased by 50~75% of topdressing N compared with 48 kg/ha topdressed N of 60 kg/ha seeding rate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.87-92
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• 2015

This experiment was conducted to evaluate the effect of seeding methods and application levels of nitrogen fertilizer on the yield and forage quality of whole crop rice (WCR). The WCR variety "Namil" was directly seeded on April 25 and transplanted on May 25. Five levels of nitrogen fertilizer were applied (90, 110, 140, 170 and 200 kg/ha). There were no significant differences (p<0.05) of the emergence date, heading date and disease resistance based on the nitrogen fertilizer rates; however, the WCR became dark at higher nitrogen fertilizer rates. The plant height increased at higher nitrogen fertilizer rates and the tiller number showed the same trend. In contrast to a direct seeding method, transplanting increased the tiller number. The dry matter (DM) content did not show a certain tendency based on nitrogen fertilizer rates, while the fresh and dry matter yields increased with incremental changes of the nitrogen fertilizer rates (p<0.01), and the transplant method increased the yield size. In yield analysis, the plot direct-seeded with 140 kg N/ha and the transplanting with 170kg N/ha showed the highest yields. The crude protein (CP) content increased with higher nitrogen fertilizer rate, but there was no significant differences between transplant and direct-seeding methods. The content of ADF (acid detergent fiber) and NDF (neutral detergent fiber) increased with higher nitrogen fertilizer rate, but total digestible nutrient (TDN) content decreased with increased nitrogen levels. Although high nitrogen applications increased the fresh and DM yields, the 140 kg/ha nitrogen fertilizer level is recommended as the proper nitrogen fertilizer level, considering both yield and the environments.

• Proceedings of the Korean Society of Crop Science Conference
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• 1989.02a
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• pp.44-45
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• 1989

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.10b
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• pp.184-185
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• 2005

• Proceedings of the Korean Society of Crop Science Conference
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• 1996.05a
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• pp.36-37
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• 1996

• Proceedings of the Korean Society of Crop Science Conference
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• 1992.05a
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• pp.100-101
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• 1992