• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.155-165
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• 2012

This study was performed to offer the data for design of the seedling bed transfer equipment to make the automation of working process in a plant factory. The seedling bed transfer equipment pushing the seedling bed with bearing wheels on the rail for interconnecting each working process by a pneumatic cylinder was made and examined. The examined transfer force to push the seedling bed with a weight of 178.9 N by the pneumatic cylinder with length of 60 cm and section area of 5 $cm^2$ was measured by experiments. The examined transfer forces was compared with theoretical ones calculated by the theoretical formula derived from dynamic system analysis according to the number of the seedling bed and pushing speed of the pneumatic cylinder head at no load. The transfer function of the equipment with the input variable as the pushing speed $V_{h0}$(m/s) and the output variable as the transfer force f(t)(N) was represented as $F(s)=(V_{h0}/k)(s+B/M)/(s(s^2+Bs/M+1/(kM))$ where M(kg), k(m/N) and B(Ns/m) are the mass of the bed, the compression coefficient of the pneumatic cylinder and the dynamic friction coefficient between the seedling bed and the rail, respectively. The examined transfer force curves and the theoretical ones were represented similar wave forms as to use the theoretical formular to design the device for the seedling bed transfer. The condition of no vibration of the transfer force curve was $kB^2>4M$. The condition of transferring the bed by the repeatable impact and vibration force according to difference of transfer distance of the pneumatic cylinder head from that of the bed was as $Ce^{-\frac{3{\pi}D}{2\omega}}<-1$, where ${\omega}=\sqrt{\frac{1}{kM}-\frac{B^2}{4M^2}}$, $C=\{\frac{\frac{B}{2M}-\frac{1}{kB}}{\omega}\}$, $D=\frac{B}{2M}$. The examined mean peak transfer force represented 4 times of the stead state transfer force. Therefore it seemed that the transfer force of the pneumatic cylinder required for design of the push device was 4Bv where v is the pushing speed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.6
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• pp.487-498
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• 1992

To study the effects of different nursing methods and transplanting on the growth of rice plant (Oriza sativa L.) in southern region of Korea, Kumo-byeo, Palgong-byeo and Dongjinbyeo were transplanted from April 20 to July 20 at an interval of 15 days with 8 days old seedling (infant seedling) and 25 days old box-seedling for machine transplanting, and 45 days old conventional seedling. Threshold transplanting date in southern region of Korea were June 26 for 8 days old seedling, July 1 for 25 days old seedling and] July 11 for 45 days old seedling for Kumo-byeo, and June 21, June 30, July 10 for Palgong-byeo, June 10, June 24, July 5 for Dongjin-byeo, respectively. Yield has no uniform tendency according to the transplanting date. However, yield were greater in the order of 8 days old seedling >25 days old seedling> 45 days old seedling in Kuma-byeo and 25 days old seedling (equation omitted)8 days old seedling (equation omitted)45 days old seedling in Palgong-byeo, 45 days old seedling(equation omitted)25 days old seedling(equation omitted) 8 days old seedling in Dongjin-byeo. The optimum accumulated air temperature during yield productive stage around heading (40 days from 10 days before heading to 30 days after heading) for high yield were 1,003$^{\circ}C$ for 8 days old seedling, 1,014$^{\circ}C$ for 25 days old seedling and 1,027$^{\circ}C$ for 45 days old seedling in Kumo-byeo. And they were 1,018$^{\circ}C$, 1,015$^{\circ}C$, 1,086$^{\circ}C$ in Palgong-byeo and 998$^{\circ}C$, 984$^{\circ}C$, 949$^{\circ}C$ in Dongjin-byeo, respectively. Earlier transplanting with 8 days old seedling showed higher ratio of broken rice and green kerneled rice in Kuma-byeo, and late transplanting after July 5 showed significant high rate of green kerneled rice. Palgong-byeo and Dongjin-byeo also showed high rate of green kerneled rice at transplanting after July 5.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.126-132
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• 2010

A high sugar rice cultivar 'Danmi' which has been recently developed and released in the Functional Crop Resource Development Division, Department of Functional Crop, National Institute of Crop Science, has high glucose and sucrose contents but has a poor seed development. This defect poses some problem in ensuring stable seedling establishment in the nursery bed. We examined the germination and seedling emergence characteristics of 'Danmi' and determined an optimum seeding rate for seedling establishment. 'Danmi' seeds has a light 1,000-grain weight of 18.2g compared with Ilmibyeo's 26.7g. The 97.4% of 'Danmi' seeds has specific gravity below 1.0 while only 2.0% of seeds was fully developed with specific gravity above 1.12. However, the reverse is true in the Ilmibyeo seed used as a control cultivar. Although the seed germination of Danmi was 89-91% regardless of seed specific gravity but at a slower rate than Ilmibyeo regardless of water soaking temperatures of $20-30^{\circ}C$ because of high seed amount of specific gravity below 1.0 in 'Danmi'. It took 2～4 days longer of seed soaking in the Danmi seeds than Ilmibyeo before germination. 'Danmi' has low normal seedling emergence rate than Ilmibyeo in the seedbed soil due to high percentage of abnormal seedlings like stunting and incomplete growth. Normal seedling emergence rate of 'Danmi' in the seedbed was 62.6～64.9% for 10-day old seedling and 83.5～86.7% for 30-day old seedling which is lower by 29.6～30.0% and 11.3～12%, respectively than Ilmibyeo. Although 'Danmi' has low normal seedling emergence rate, but it has greater seed number per weight basis. Therefore, based on the normal seedling number per unit area of Ilmibyeo(control cultivar) for seedling rate of 10-day and 30-day old seedlings, the recommended seeding rate of 'Danmi' for transplanting rice is 220g seeds for 10-day old seedling and 130g for 30-day old seedling per nursery box, which is equivalent to 1.5 times seed volumes of Ilmibyeo.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.381-390
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• 2018

This study was conducted to examine the growth characteristics of seedlings of several major fruit vegetables and compare them between plants grown with the conventional plug seedling system (Plug) and those grown with the cylindrical paper pot system (CPP). There were no significant differences in shoot growth characteristics, such as plant height, leaf area, dry weight, and fresh weight, between tomato, cucumber, and watermelon plants grown with the CPP and Plug systems. The total root lengths of tomato and cucumber plants grown with Plug were longer than those grown with CPP at the beginning of seedling growth, and the total root lengths of watermelon grown with Plug were longer than those grown with CPP throughout the whole seedling period. The length of root that separated five steps according to the diameter of the root of tomato did not differ between CPP and Plug, but those of cucumber and watermelon were 20-251% longer with Plug than with CPP for all kinds of roots. The fresh weight of Plug-grown tomato roots was about 30% heavier than that of CPP-grown tomato during the seedling period, but the difference decreased as growth progressed. Finally, there was no difference between plants before and after transplanting. The fresh weights of the Plug-grown plants were about 20-30% heavier than those of CPP-grown ones in terms of the whole seedling. After transplanting to the Wagner pot, the shoot growth of Plug-grown watermelon plants in terms of dry weight was low until 7 days had passed. However, this tendency was reversed from 8 days after transplantation onward. In conclusion, there were no significance differences in the growth of shoots between plants grown with the CPP and Plug systems. However, root development was better with Plug than with CPP.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.47-52
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• 2010

This study was carried out to investigate the availability of covering material used for raising seedlings in the rice nursery bed. The pre-germinated seeds of a rice cultivar 'Chilbo' were sown into seedling tray ($60{\times}30{\times}2.5cm$) on 20th April and 3rd May 2010. Polypropylene spunbonded fabric (PSF) and lagging were used for covering materials in rice nursery bed. The growth characteristics of seedlings were evaluated at 8, 15 and 25 days after sowing (DAS) in the nursery beds covered with PSF and lagging, respectively. The plant height of 8-day old seedlings grown in lagging nursery bed was longer by 2cm than those in PSF nursery bed when the seeds were sown on 20th April, but seedling quality grown in lagging nursery bed was poor compared with that in PSF nursery bed. The growth characteristics of 15-day old seedlings were similar to that of 8-day old seedlings. The plant height of 8, 15 and 25-day old seedlings grown in lagging nursery was longer than those in PSF nursery when the seeds were sown on 3rd May. The seedling quality grown in PSF nursery was better than that in lagging nursery. The seedlings grown in PSF nursery have more leaves and better seedling quality compared with that of lagging nursery. The seedling quality was remarkably decreased with the increase of nursery period in lagging bed but seedlings quality were recovered at 5 days after hardening treatment by removing the lagging.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.709-717
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• 2013

The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.27-31
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• 1977

Experiments were conducted to investigate the effects of seed bed soils and soil pH on the rice growth and control of seedling rots. A 2:1 ratio mixture of clay loam and compost resulted in the best seedling growth and quality among the soils used. At soil pH between 4 and 5. no seedling rots occurred and plant growth was normal. At soil pH above 6, seedling rots occurred and characteristics of seedings was poor. Tachiga ren application before seeding or immediately after seeding reduced seedling rots significantly at the high soil pH.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.50-50
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• 2017

Swampland is a potential alternative land to be used in various agricultural production activities in Indonesia, because Indonesia have 33.41 million hectares of swamp land that consists of 13.28 million hectares nontidal swamp and million hectares 20.13 tidal swamp. In the province of South Sumatra, because of unpredictable water level in the field before planting, farmers have been doing agronomic adaptation method through the delay time of transplanting and forced to apply more than one the nursery practice with the combination of a floating nursery method and a dry-bed nursery method. This study was aimed to (1) evaluate the seedling growth and tillering pattern of several popular Indonesian rice varieties, and (2) look for alternative technologies to get a better rice seedlings under two nursery methods in the nontidal swamp land. In the first experiment, the seedling growth characteristics of five rice varieties (Ciherang, Inpara 5, Inpara 9, Inpari 29, and Inpari 30) was evaluated by two methods of nursery, i.e. floating nursery and dry-bed nursery. In the second experiment, rice variety of Inpari 30 was treated with Zn seed priming and foliar fertilizer of 2,300 ppm N at the nursery stage. Those treatments were combined with the time of seedling under floating and dry-bed nursery. The results of the first experiment showed that of the five varieties tested, dry-bed nursery method showed better seedling growth than floating nursery. This was indicated by high leaf number, tiller number, tillers pattern, shoot-root ratio and relative growth rate. Ciherang and Inpari 30 showed high tiller number, and they had produced tertiary tiller in the sixth week of observation. Moreover, shorter period of floating and dry-bed nursery in combination with the treatment of Zn seed priming and spraying seedling with foliar fertilizer N could improve the growth of seedlings.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.133-135
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• 2003

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.194-197
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• 2005

This experiment was conducted to investigate the effect of turf growth characteristics to different transplanting times. It observed that the turf growth was decreased according to delaying the transplanting time. In respect to the turf growth characteristics, it appeared that there was good for transplanting time to transplant the turf seedling before early July. With sustaining the short day length after early July, it shown that number of branch on stolen, number of nodes and Total length of stolen were apparently decreased. Especially, number of branch on stolon was decreased from 2nd up-growing branch.