• Korean Journal of Plant Resources
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• v.37 no.4
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• pp.392-400
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• 2024

This study was conducted to find the flowering and growth characteristics according to the different altitudes (plains and mid-mountain regions) and cultivation methods (field and plastic houses cultivation) of Elsholtzia splendens. Experimental regions located at 12 meters and 500 meters above sea level were selected for the plains and the mid-mountain, respectively, and the same method was applied for cultivation management by different altitudes and cultivation methods. In the mid-mountain region, flower bud emergence (2-3 days), flowering (9 days), and full bloom (6-7 days) stages of Elsholtzia splendens were earlier than in the plains, and field cultivation was earlier than plastic house cultivation. The plant height, the main stem diameter, and the number of branches tended to increase gradually after an initial rapid growth at 59 to 69 days after planting date. The days of duration of sunshine (less than 8 hours) from the rainy season (June 20) to the period when vegetative growth increases gradually (59 to 69 days after planting) was 22 to 29 days and 26 to 35 days in the plains and the mid-mountain regions respectively, and this period was estimated time of transition from vegetative growth to reproductive growth. The spikes growth of Elsholtzia splendens by cultivation altitudes was higher in the mid-mountain region than in the plains, and there were no statistically significant differences in growth characteristics except for the main stem diameter, the number of branches, and the dry matter. Also, the amount of flowering and growth was higher in the plastic house cultivation compared to the field cultivation. As a result, some differences in flowering amount were observed when cultivating Elsholtzia splendens for landscaping purposes, but it was considered possible to cultivate in both plains and mid-mountain regions. This study therefore provides ecological information for understanding the relationship between weather characteristics and growth of Elsholtzia splendens.

• Plant Resources
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• v.8 no.2
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• pp.81-86
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• 2005

An efficient plant regeneration system of Gentiana scabra through somatic embryogenesis was established. Leaves and roots of seedlings of Gentiana scabra excised after germination were cultured on MS basal medium with 2,4-D, NAA or BA. Embryogenic callus was obtained on MS medium with 0.5 mg/L 2,4-D alone or 0.1 mg/L 2,4-D combimation with 1.0 mg/L BA after 45 days of culture. These embryogenic calli gave rise to somatic embryos, which subsequently developed into plantlets on MS medium without PGRs. Also, shoots were effectively differentiated from embryogenic callus when root segments were cultured on MS medium supplement with 0.1 mg/L 2,4-D and 1.0 mg/L BA. Shoots were effectively rooted on MS medium without PGRs. In vitro flowers were formed from plantlets cultured on MS medium with $5\%$ sucrose after 60 days of culture.

• FLOWER RESEARCH JOURNAL
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• v.18 no.2
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• pp.142-146
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• 2010

'Arirang', an early-flowering pure white gladiolus with purple core, was released by the National Institute of Horticultural & Herbal Science (NIHHS) in 1998. The selection was derived from the cross between the progenies of the early flowering dark orange 'Arianne' and bright red domestic cultivars 'Hongkwang'. The breeding was conducted in 1993 and finally selected in 1998 after five (5) years (1994 to 1998) of experimentation. 'Arirang' is a cut flower with bright white color petals and purple core which exhibited early flowering and vigor without stem bending. These can be cultivated in areas or regions with strong winds during summer. 'Arirang' has a very firm growth form and sturdy branches which do not bend when planted in the open fields. Likewise, the plant had high tolerance to flooding and resistance hence could grow vigorously in open areas. It is a fast- growing plant which exhibits high corm production rate. 'Arirang' had a 10.5 cm wide flower and 140 cm plant height. During summer, the average number of days to flowering was recorded at 75 days of 'Arirang'. Top dressing must be conducted once or twice during corm production to enhance corm quality and quantity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.207-219
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• 2016

Incandescent (INC) lamps have been commonly used to promote flowering of long-day (LD) plants during short-day (SD) seasons, but production of INC lamps has been prohibited due to their low energy efficiency. One of the light sources replacing INC lamps is a compact fluorescent lamp (CFL). This study was carried out to compare the flowering and morphological responses of LD annuals grown in a controlled environment greenhouse at $20^{\circ}C$ with a truncated 9-h SD and a 2- or 4-h night interruption (NI) or 6-h day extension (DE) provided by lighting from INC lamps, CFLs, or a combination of the two (INC + CFLs), in which red (R) to far-red (FR) ratios were 0.60, 8.46, and 0.91, respectively, and their PPFDs were $2.3{\pm}0.3{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. After 12 weeks of treatment, $Petunia{\times}hybrida$ 'Wave Purple' plants did not flower under the SD photoperiod whereas 100% flowered under all of the LD treatments. Flowering was more rapid under the INC or INC + CFL lighting treatments compared to CFL and DE, and 4-h NI enhanced flowering compared to 2-h NI. In addition, plants under DE and 4h-NI generally flowered earlier than under 2-h NI. All petunia 'Single Dreams Red' plants flowered within 65 days after treatment, and flowering was hastened by some LD lighting regimens and lamp types. Plants under DE and 4h-NI generally flowered earlier than under 2-h NI INC or INC + CFL compared to FL, and flowering time under INC 6-h DE was earliest. In addition, INC lighting promoted stem elongation of both petunia cultivars. In both pansy (Viola${\times}wittrockiana$) 'Coiossus Yellow' and 'Delta Blue Blotch', LD treatments, especially using INC lamps, promoted flowering whereas the lighting period had little influence on days to flowering. Therefore, INC or INC + CFL with lower R:FR promoted flowering and stem extension and the promoting effect was larger with longer lighting periods. These results suggest that CFLs can be used to provide LDs to promote the flowering of petunia and pansy and to reduce stem elongation, although the promoting effect on flowering is sometimes less than that of INC lamps alone.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.315-319
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• 2012

This study was conducted to select plant growth regulators effective at ginseng berry set inhibition to help root growth in Korean ginseng (Panax ginseng C. A. Meyer). PGRs (ethephon, gibberellic acid, maleic hydrazide, coumarin) were applied to field grown 5-year-old Korean ginseng between one and two times, before and during bloom in 2009, 2010. The number of treatment was more effective in ginseng berry set inhibition when used two times compared with one time in GA 1,000 ppm, MH (5,000, 10,000 ppm), coumarin (5,000, 10,000 ppm) treatment. According to treatment period of plant growth regulator, ginseng berry set inhibition rate from 20days before flowering date to 5days after blooming was the highest in MH 5000 ppm showing 99.9% and the lowest in GA 100 ppm showing 32.8%. The spray treatments of Ethephon (50, 150 ppm) and MH (5,000, 10,000 ppm) from 20 days before the flowering bloom up to 5 days before, and coumarin (5,000, 10,000 ppm) from 20 days to 6 days and before blooming that induced the inhibitory effect more than 90% after 12 weeks. Considering ginseng berry set inhibition characteristics and treatment period ethephon and coumarin was important about applied period but, MH treatment appeared to effective ginseng berry set inhibition regardless of treatment period.

• Proceedings of the Korean Society of Crop Science Conference
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• 1986.06a
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• pp.102-103
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• 1986

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.304-310
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• 2017

This study was conducted over a 3-year period from 2013 to 2015 in the mid-northern inland, Cheolweon, Korea, to investigate changes in flowering date, daily mean temperature during grain filling, and yield characteristics affected by transplanting date in an early-maturing rice variety, 'Joun'. Thirty-day-old seedlings were transplanted at four different dates at 15-day interval from May 5 to June 19. Flowering dates were July 16, July 21, July 31, and August 14 when transplanting was performed on May 5, May 20, June 4, and June 19, respectively. Late transplanting resulted in higher daily mean temperature before flowering but late-transplanted rice required fewer days and lower cumulative temperature to reach flowering from transplanting. As transplanting was delayed, daily mean temperature for 40 days after flowering decreased, whereas daily sunshine hours for the same period increased, with a temperature of $24.8^{\circ}C$ and sunshine for 5.8 hours being recorded at the transplanting on May 5, and with a temperature of $21.0^{\circ}C$ and sunshine for 7.7 hours at the transplanting on June 19. With late transplanting, panicles per square meter significantly decreased, whereas spikelets per panicle showed an increasing trend. Regression analysis showed that maximum head rice yield was attained from the transplanting on May 18, for which the flowering date was July 21, and daily mean temperature for 40 days from that flowering date was $24.6^{\circ}C$. A decrease in head rice yield by 5% and 10% of the maximum was observed for rice transplanted on June 6 and June 15, which resulted in flowering dates of August 2 and August 11, respectively, and the daily mean temperatures for 40 days from flowering were 23.2 and $21.7^{\circ}C$, respectively. Therefore, in mid-northern inland, it is recommended to transplant 'Joun' on May 18 to induce flowering on July 21, when grain filling is subjected to a daily mean temperature of $24.6^{\circ}C$ during active filling stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.2
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• pp.127-131
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• 2012

In this study we examined the changes in expression of pigments in black rice during kernel development, which were sampled at 2~3-day intervals to the 40th day after flowering. The first expression of pigment on kernels was observed on the seed coat about 5 days after flowering. At that times, the ratio of pigment expression was 0.08% of total area. The order in expression of pigments in black rice during kernel development was top first, followed by bottom, dorsal side, then ventral side. Maximum percentage of the total colored area in kernel was about 25 days after flowering. After that, the color has changed to dark purple from pale purple during kernel development after flowering. After harvesting, the non-uniform color kernels were observed. As a result, the ventral side in a kernel was a position of the non-uniform color such as a mixture of pale purple and dark purple. Also, we could be concluded that patten of pigment expression was similar in kernel development.

• Journal of Environmental Science International
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• v.23 no.9
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• pp.1573-1581
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• 2014

This study was conducted to examine the effect of LED light quality and supplemental LED light on growth and flowering for potted flowering plant of Kalanchoe. 1. Plant height of Kalanchoe was enhanced under Red, regardless of treatment time. 2. Root length and stem diameter of Kalanchoe were enhanced by Red+Blue. 3. The number of internodes was not influenced by LED light quality. Length of flower stalk of Kalanchoe increased under Red+Blue, but treatment time did not result in statistically significant differences. 4. Leaf area was not influenced by LED light quality in Kalanchoe. 5. The number of flower buds and open flowers was decreased by LED light treatment, but days to flowering was reduced by Red+Blue for 4 hr after sunset in Kalanchoe. 6. Chlorophyll and anthocyanin content was not significantly affected by LED light treatment, but anthocyanin content tended to increase by Blue 4 hr after sunset. 7. Fresh and dry weight did not increased by LED light treatment in Kalanchoe.