• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.152-157
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• 2009

To obtain pure lines for breeding $F_1$ varieties of Primula malacoides, 10 lines that were considered uniform in growth and flowering characteristics were selected from self-crossings of the sixth generation ($S_6$). Plant height of the selected lines ranged from 20.8 to 33.2 cm, and number of leaves ranged from 33.6 to 54.2. The selected lines flowered at 181.4 to 207.8 days after sowing. Three lines, including 'PR-03-81', flowered in less than 190 days from sowing, while six lines, including 'PR-03-228', only flowered after more than 200 days from sowing. In terms of petal color, six lines, including 'PR-03-81', were pink, three, including 'PR-03-236', were purple, and line 'PR-03-275' was white. Flower diameter ranged from 2.4 to 2.9 cm, and number of pedicels per plant was between 15.4 and 26.4. Number of flowers per pedicel ranged from 20.2 to 30.2. Germination was more than 70%, and number of seeds per capsule (pod) ranged from 110.0 to 162.8. In summary, plant height was low and flower diameter was small and plants had many flowers and readily formed seeds. The selected lines are not only valuable as ornamental plants but could also be used as breeding materials for $F_1$ hybrids of Primula polyantha.

• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.65-71
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• 2021

This study was carried out to investigate the effect of the final irrigation timing (FIT) before packaging for long-term transportation on growth, flowering, and crop quality of Phalaenopsis after simulated dark shipping (SDS). Phalaenopsis Sogo Yukidian 'V3' plants grown in 11 cm-diameter plastic pots filled with potting media (sphagnum moss + bark or only sphagnum moss) were packaged in paper boxes for export at 3.5, 7, 10 days (FIT 3.5, 7,10; Experiment 1) and 4, 6, 8, 10 days (FIT 4, 6, 8, 10; Experiment 2) after the final irrigation and then stored in a growth chamber at 20 ± 1℃ and 70 ± 3% RH created for SDS. After 4 weeks, the plants were taken out and grown in a greenhouse at 23 ± 3℃ and 70 ± 5% RH, and crop characteristics were measured during cultivation. In Experiment 1, the survival rate of FIT 3.5 plants was lower than that of FIT 7 and FIT 10. There was no difference between treatments in days to first flower, the number of florets, and the elongation rate of flower stalks. In Experiment 2, the percentage of rotted leaves was lowest in FIT 6 when before forcing and at 12 weeks after forcing, and that of FIT 8 was similar to FIT 6 when before forcing, but slightly increased after 12 weeks. The percentage of rotted leaves of FIT 10 was highest and that of FIT 4 was also high. There was little difference in flowering characteristics among treatments. In conclusion, the FIT before packaging for long-term (4 weeks) transportation of potted Phalaenopsis 'V3' affected the leaf rot rather than the post-shipping growth and flowering. And it was considered appropriate to set the volumetric water content of the potting media just before packaging to about 30%.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.101-105
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• 2012

'Secret Pink' was released by National Institute of Horticultural & Herbal Science in 2008. The cross was made between '03B1-23' and 'Sei-Monaco in 2005'. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2006 to 2008, 'Secret Pink' was selected finality. The natural flowering time of 'Secret Pink' was the middle of October, and it is possible to flower all year round by shade and light culture. It has single type flowers with pink petals. The growth of plant was very vigorous and response time was 6.5 weeks. The diameter of flower was 6.7 cm. Number of flowers per stem and petals per flower were 14.5 and 25, respectively. Days to flowering under the short day treatment was about 50 and its vase life was 25.5 days in autumn season.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.388-392
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• 2013

A spray chrysanthemum cultivar 'Green Candy' was released by National Institute of Horticultural & Herbal Science, Rural Development Administration, in 2009. The cross between 'Yoko Ono', a spray chrysanthemum cultivar with light yellowish-green double type, and 'Green Bird', a spray chrysanthemum cultivar with vigorous and green double type, was made in Suwon in 2006. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2007 to 2009, 'Green Candy' was selected finality. The natural flowering time of 'Green Candy' is October 28th, and it is possible to flower all year-round by shade and light culture. It has double flower type with green petals. The growth of plant is very vigorous and the color of the petals is stable when the variety is cultivated under high temperature conditions in summer season. The diameter of flower is 4.1 cm. The numbers of flower per stem and petals per flower are 12 and 217, respectively. The days for flowering under the short day treatment are about 58 and its vase life is 18.1 days in autumn season. 'Green Candy' was applied as No. 2010-212 on March 5, 2010 for variety protection and the plant variety protection rights have been registered as No. 3633 on August 2, 2011 at the Korea Seed and Variety Service.

• Korean Journal of Agricultural Science
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• v.27 no.2
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• pp.86-94
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• 2000

This study was carried out to determine the effectiveness of uniconazole in ameliorating low and high temperature injury in tomato plants(Lycopersicon esculentum Mill. cvs. Fireball and Patio). Plants were given a soil drench of 0, 0.001, 0.01 or $0.1mg{\cdot}pot^{-1}$ uniconazole, and after 14 days, were treated with 12-h day/12-h night cycles at $25/25^{\circ}C$, $2.5/25^{\circ}C$, $25/2.5^{\circ}C$ or $40/40^{\circ}C$ for 4 days in controlled-environment chamber. Number of damaged leaves per plant, reduction of stem elongation, and overall injury were high at $2.5/25^{\circ}C$, but more reduction of leaf elongation, delay of flowering, and abortion of floral bud were observed in plants at $40/40^{\circ}C$. There was difference in degree of injury between cultivars, thus, 'Fireball' was much affected by unfavorable temperature regimes. All concentrations of uniconazole reduced leaf and stem elongation, increased total chlorophyll concentration, delayed flowering, and significantly provided protection against low and high temperature injury in two cultivars. In general, the application of uniconazole did not inhibit flowering delay and floral bud abortion induced by high and low temperature exposure. Our results support the hypothesis that the role of uniconazole is related to defense system against oxidative stress induced by low temperature stress. Further research is required to clarifu the phytoprotective mechanism of this compound agaist high temperature stress.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.478-482
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• 2001

This experiment conducted to know physiological characteristics and stress effect on different growth stage of soybean by night illumination. Soybean variety, Shinpaldalkong 2, Keumjungkong and Muhankong were treated by night illumination with 20~30 Lux (0.05~0.08W m$^{-2}$ , 0.24~0.36 $\mu$㏖ S$^{-1}$ m$^{-2}$ ) for 15 days at six different growth stage, seedling, pre-floral initiation, post-floral initiation, pod filling and seed ripening stage. Night illumination delayed flowering to 2~8 days compared to control. Delay of flowering by night illumination severely effected at the pre-floral initiation stage. Stem length was increased all the night illumination treatments except the pod filling stage. Number of nodes in Shinpaldalkong 2 and Keumjungkong 1 were increased until before post-floral initiation stage but in Muhankong were increased until after post-floral initiation stage by night illumination treatments. Number of pods were decreased all the night illumination treatments except seedling stage compared with control. Yield decreased all the treatments and severe the loss rate degree showed the order of prefloral initiation, post-floral initiation, seedling and flowering stage.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.43-51
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• 2022

This study was conducted to investigate the effect of ventilation at high temperature on the control of powdery mildew, silverleaf whitefly two-spotted spider mite occurred at Korean melon cultivation greenhouse, and on leaf rolling and flowering of the plant in summer season. 'Alchanggul' grafted onto 'Hidden Power' rootstock was planted on soil bed with the distance of 40 cm. Three ventilation temperatures of 45℃, 40℃, and 35℃ as set points were compared. Ventilation treatment was done by control of side window operation from 18th June to 13th July when silverleaf whitefly, mite, and powdery mildew were occurred in all greenhouses. The temperature inside greenhouse was increased up to the set temperature point on sunny days and maintained for about 9 hours with high relative humidity at 45℃ condition. The differences of day maximum air temperature and day minimum RH were the highest at 45℃ treatment. After 11 days of treatments, the damage by powdery mildew and two-spotted spider mite was almost recovered at 45℃ treatment but not at 40 and 35℃. The population of silverleaf whitefly and two-spotted spider mite were significantly decreased at 45℃ treatment at 14 days after treatment, while powdery mildew symptom was not significantly decreased. Leaf rolling was observed at high temperature but not severe at 45℃ treatment. After 26 days of treatments, female flowers did not bloom at all at 45℃ treatment, and the number of male flowers was 1.2 among 15 nodes of newly grown shoots. As the result, it indicates that ventilation at the high temperature of 45℃ for about 2 to 3 weeks can be an applicable method to control above mentioned pests and disease, and to recover the vegetative growth of Korean melon by reducing flowering of the plant.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.402-412
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• 2023

Peucedanum japonicum Thunberg is a biennial plant that usually flowers and dies after seed setting at 2^nd year. We inspected the flowering and fertilization characteristics to establish the breeding system. The plant forms complex umbel inflorescences consisting of multiple umbellets and numerous flowers. Each flower is bisexual but allogamous because of protandry. A flower bloomed for three days with matured pollen and no stigma appearance. Inspection of pollen tube growth indicates that the pollen viability can be maintained for up to 3~7 days after first flowering (DAF). In a umbellet, flowers bloomed during 1~5 DAF and the pollen maintained viability during 3~10 DAF, and the pistil developed and maintained fertility during 8~12 DAF. Theoretically, self-pollination can be possible during 8~10 DAF in the same umbellet. Approximately 4.4% of seeds were developed by self-pollination among flowers in an enveloping solitary umbel. There is at least a 9~10 days difference for the development of an umbel with another umbel at the next branch, which indicates pollination can be permitted between different branches in an individual plant. Finally, we have established a rapid breeding method to shorten the breeding cycle to one year from two years by integrating the flowering and pollination characteristics.

• Korean Journal of Medicinal Crop Science
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• v.16 no.5
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• pp.287-293
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• 2008

This study was conducted to determine the characteristics of fertilization process and embryo development of Astragalus membranaceus Bunge (Astragali Radix) to provide basic data needed in its breeding. A. membranaceus showed poor seed setting when self-pollination was induced. When artificial pollination was induced, it showed less than 5% bearing in late August, but more than 13% bearing from the beginning of September 4th. The flower size was about $17.0\;mm{\times}4.0\;mm$ and pistils and stamens had the same length of 15.0mm at flowering stage. When self-pollination or cross-pollination was induced, pollen tubes extended to an ovule. While pollen tube was extending to the ovule, reproductive cell split and formed two male generative nuclei and a vegetative nucleus. In the case of self-pollination, fertilized embryo was not observed, but was formed in the case of cross-pollination. A. membranaceus is noted to have zygote self-incompatibility. In the case of cross-pollination, fertilization was observed in 6 to 8 h after pollination, where apical cell derivatives split after fertilization. A spherical pro-embryo was then formed three days after fertilization. The seed attained full shape with a seed coat showing its distinctive contour 15 days after fertilization. Thus, A. membranaceus in Leguminosae family is found to have zygote selfincompatibility although its flower shape is shown to match the self-compatibility plant.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.289-297
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• 2006

In this study we examined the changes in weight and dimension, protein and amylose contents, and pasting properties of brown rice flour, as well as the gelatinization properties of starch, from two non-waxy japonica cultivars and one waxy japonica cultivar planted in an experimental field in 2002 under the same fertilizer conditions. The weight of both rough and brown rice increased consistently up to 42 days after flowering (DAF) for the non-waxy rice and to 35 DAF for the waxy rice. The changes in dimension of the brown rice kernel indicated that the length was maximized first, followed by breadth and then thickness. The protein content of the non-waxy rice remained fairly constant, but that of the waxy rice decreased by about 1% after 14 DAF. The amylose content of the non-waxy brown rice flour increased, but that of the waxy brown rice flour decreased during kernel development. As the kernel developed, the peak viscosity of the non-waxy rice flour increased up to 35 DAF, after which it decreased, whereas that of the waxy brown rice flour increased consistently. The gelatinization temperature of starch also increased in the waxy rice during kernel development up to 21 DAF. The gelatinization enthalpy of starch, however, increased in all rice cultivars throughout the kernel development.