• Horticultural Science & Technology
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• v.33 no.1
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• pp.31-38
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• 2015

This study was carried out to investigate the relationship between endogenous polyamines (PAs) and floral bud differentiation in chrysanthemum (Chrysanthemum morifolium). In this study, PA content (free, bound, and conjugated) in apical buds, leaves, and roots changed appreciably during floral bud differentiation. PAs accumulated during series of processes such as floral induction, differentiation of floret primordia, and crown formation in apical buds; changes in PAs in apical buds may have a relationship with those in leaves and roots. The levels of free PAs and conjugated PAs [putrescine (Put) and spermine (Spm)] in apical buds rapidly increased during the initiation stage of floral bud differentiation, while free and conjugated spermidine (Spd) reached their highest levels at the stage of floret primordium differentiation. In the free, conjugated, and bound PA fractions, the changes in Spm content were negligible compared to those of Put and Spd throughout the experiment. These findings indicate that PAs participate in regulating the process of flower bud differentiation in chrysanthemum.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.328-332
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• 2011

After preparation of acetone, ethanol, methanol, and water extracts (10 g/300 mL) of dried persimmon (Diospyros kaki cv. Fuyu) flower-buds, total phenolic contents (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (RSA), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) RSA, reducing power (RP), and tyrosinase inhibitory activity of the extracts were evaluated. The methanol extracts produced the highest TPC (113.39 mg gallic acid equivalents/g), DPPH RSA ($IC_{50}=40.25\;{\mu}g/mL$), ABTS RSA ($IC_{50}=58.17\;{\mu}g/mL$) and RP ($IC_{50}=69.43\;{\mu}g/mL$) activities while the water extracts generated the lowest values. The ethanol extract showed the highest tyrosinase inhibitor activity (88.90%) at a concentration of 1 mg/mL. These results indicated that persimmon flower-buds may be a useful source of natural antioxidants.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.1
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• pp.39-47
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• 1985

Normally cultured aromatic tobaccos, KA 101 and KA 103, were primed progressively in three-leaf segments, either 7 days before bud, bud, or early flower stage with 7 days interval, respectively, The cured leaves were weighed for yield, graded, analyzed for quality-related constituents including volatile aroma components. Also the cured leaves were manufactured and smoked by panelists. Yield and quality by price decreased with advancing ripeness. Reducing sugar, total nitrogen, protein nitrogen decreased with successive ripeness, but reverse in this trends with nicotine, petroleum ether extracts and volatile acids components. Among volatile neutral components, furfural, furfuryl alcohol, benzyl alcohol, penethyl alcohol and p-cresol decreased, but solanone increased with delayed harvest. Neophytadiene, oxysolanone, furfuryl aceton was highest at mid harvest, which was judged to be best by panelists. Mid harvest, first primed at bud stage when leaf color comes to pale green to yellow green, seems to be highly recommendable.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.89-95
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• 2011

This study was conducted to improve commercial quality of cut spray chrysanthemums 'Charming Eye' and 'Pink Pride' bred in Korea by foliar application of daminozide, suppressing excessive elongation of peduncle caused by high temperature in greenhouse. Applications were made at two floral-bud-developmental stages and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. As for 'Charming Eye', cut flower length, peduncle diameter, stem diameter, flower bud diameter, and the number of flower buds did not show any significant difference among all treatments including control. However, the suppressing effect of peduncle elongation, widening angle of flower cluster arrangement on apical part, and increasing parallel flower buds in stage I showed better than those in stage II regardless of daminozide concentration. As for 'Pink Pride', cut flower length, peduncle diameter, and stem diameter did not show any significant difference among all treatments including control but angle of flower cluster on apical part increased compared to control as daminozide was sprayed at stage I and II except $2,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage II. The number of flower buds and flower bud diameter showed the greatest increment through $1,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage I and did the least values as sprayed with $2,000mg{\cdot}L^{-1}$ daminozide at stage II. Daminozide also gradually reduced peduncle length in a concentration-dependant manner but elongation of peduncle foliar-sprayed at stage I showed the more suppressing effect than that at stage II. Increasing the number of parallel flower buds showed the best results when sprayed with $2,000mg{\cdot}L^{-1}$ at stage I. In conclusion, we recommended that foliar spraying with $500-1,000mg{\cdot}L^{-1}$ daminozide at stage I and foliar spraying with $1,000-2,000mg{\cdot}L^{-1}$ daminozide at stage I improved cut flower quality of 'Channing Eye' and 'Pink Pride', respectively.

• FLOWER RESEARCH JOURNAL
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• v.18 no.4
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• pp.231-237
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• 2010

This study was conducted to improve commercial quality of a cut spray chrysanthemum 'Ilweol' bred in Korea by foliar application of daminozide, suppressing excessive elongation of peduncle caused by high temperature in summer season production. Applications were made at three floral bud developmental stage (I, II, and III), and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. Cut flower length and peduncle length showed the greatest repression of elongation through daminozide treatments at stage III and stage II, respectively. Daminozide also gradually reduced values of those in a concentration-dependant manner. Flower diameter increased compared to control as daminozide was sprayed at later stage but decreased in daminozide concentration-dependant manner. Angle of flower cluster on apical part of whole plant showed the best results when sprayed with $2,000mg{\cdot}L^{-1}$ at stage III. Among all combinations, $2,000mg{\cdot}L^{-1}$ daminozide at stage II recorded the highest angle of flower cluster and showed 31.3% increment as compared to control. The number of fully expanded flowers showed the highest values using $2,000mg{\cdot}L^{-1}$ daminozide at stage III than the other treatments and total floral buds also showed the highest values using $2,000mg{\cdot}L^{-1}$ daminozide at stage I than the other treatments. In cut spray chrysanthemum cultivar 'Ilweol' bred in Korea, foliar-applying with $2,000mg{\cdot}L^{-1}$ at stage III most effectively suppressed excessive peduncle elongation, angle of flower cluster, and increased the number of flowers in summer. However, this combination affected negatively the other commercial qualities, reducing cut flower length and flower diameter. Therefore, we recommended that foliar application stage and daminozide concentration was stage III and $500mg{\cdot}L^{-1}$, respectively, in a practical culture and cut flower quality for 'Ilweol'.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.273-276
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• 1995

In vitro propagation of Neoregeria carorinae 'Tricolor' was achieved by using immature flowers and lateral buds, and the plantlets from tissue culture were transplanted and cultivated in greenhouse. The picking times of explants to decrease disappearance of stripes, and in vivo the growth and flowering of regenerated plantlets as influenced by in vivo healed nun were investigated. The normal plantlet were obtained at a frequency of 67%, in the culture of immature flowers picked at 4 weeks after flower bud differentiation, while all leaf stripes disappeared in the culture of immature flowers picked 1 and 5 weeks after flower bud differentiation. In vivo growth of plantlet from immature flower buds was better than those from lateral buds, and the flowering of 27.8% showed in the greenhouse culture of plantlet from immature culture, but the plantlets from lateral buds did not flower at all. The plantlets rooted on the medium with 0.5 mg/L IBA were the most favorable in green house culture, and the kinds and concentrations of auxin in vitro did not have any influence on variation of plane cultured in greenhouse.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.69-89
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• 1981

Stevia (Stevia rebaudiana Bertoni) is a perennial herb widely distributed in the mountainous area of Paraguay. It belongs to the family Compositae and contains 6 to 12 percent stevioside in the leaves. Stevioside is a glucoside having similar sweetening character to surgar and the degree of sweetness is approximately 300 times of sugar. Since Korea does not produce any sugar crops, and the synthetic sweetenings are potentially hazardous for health, it is rather urgent to develop an economical new sweetener. Consequently, the current experiments are conducted to establish cultural practices of stevia, a new sweetening herbs, introduced into Korea in 1973 and the results are summarized as followings: 1. Days from transplanting of cuttings to the flower bud formation of 6 stevia lines were similar among daylengths of 8, 10 and 12 hours, but it was much greater at daylengths of 14 or 24 hour and varietal differences were noticable. All lines were photosensitive, but a line, 77013, was the most sensitive and 77067 and Suweon 2 were less sensitive to daylength. 2. Critical daylength of all lines seemed to be approximately 12 hours. Growth of plants was severely retarded at daylengths less than 12 hours. 3. Cutting were responded to short daylength before rooting. Number of days from transplanting to flower bud formation of 40-day old cuttings in the nursery bed was 20 days and it was delayed as duration of nursery were shorter. 4. Number of days from emergence to flower bud formation was shortest at short day treatment from 20 days after emergence. It was became longer as initiation of short day treatment was earlier or later than 20 days. 5. Plant height, number of branches, and top dry weight of stevia were reduced as cutting date was delayed from March 20 to May 20. The highest yield of dry leaf was obtained at nursery duration of 40-50 days in march 20 cutting, 30-40 days in April 20 cutting, and 30 days in May 20 cutting. 6. An asymptotic relationship was observed between plant population and leaf dry weight. Yield of dry leaf increased rapidly as plant population increased from 5,000 to 10,000 plants/10a with a reduced increasing rate from 10,000 to 20,000 plants/l0a, and levelled off at the plant population higher than 20,000 plants/l0a. 7. Stevia was adaptable in Suweon, Chengju, Mokpo and Jeju and drought was one of the main factors reducing yield of dry leaf. Yield of dry leaf was reduced significantly (approximately 30%) at June 20 transplanting compared to optimum transplanting. 8. Yield of dry leaf was higher in a vinyl house compared to unprotected control at long daylength or natural daylength except at short day treatment at March 20. Higher temperature ill a vinyl house does not have benefital effects at April 20 transplanting. 9. The highest content of stevioside was noted at the upper leaves of the plant but the lowest was measured at the plant parts of 20cm above ground. Leaf dry weight and stevioside yield was mainly contributed by the plant parts of 60 to 120cm above ground but the varietal differences were also significant. 10. Delayed harvest by the time of flower bud formation increased leaf dry weight remarkably. However, there were insignificant changes of yield as harvests were made at any time after flower bud formation. Content of stevioside was highest at the time of flower bud formation and earlier or later harvest than this time was low in its content. The optimum harvesting time determined by leaf dry weight and stevioside content was the periods from flower bud formation to right before flowering that would be the period from September 10 to September 15 in Suweon area. 11. Stevioside and rebaudioside content in the leaves of Stevia varieties were ranged from 5.4% to 14.3% and 1.5% to 8.3% respectively. However, no definit relationships between stevioside and rebaudioside were observed in these particular experiments.

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.98-99
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• 2003

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.206-212
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• 2009

We investigated the patterns of freeze injury in dormant 'Changhowon Hwangdo' peach fruit by observing the extent of browning and germination of the branches that were treated with freezing temperature sets simulating the process of natural freezing incidences in orchards. Under the treatment of freezing temperature of $-15^{\circ}C$, the browning ratios were 15% for flower bud and less than 3% for both leaf bud and cambium. Under the $-20^{\circ}C$ treatment, the browning ratios were 40% for both flower and leaf buds and 1% for cambium. The browning ratios were 86%, 68% and 40% respectively for flower bud, leaf bud, and cambium under the $-25^{\circ}C$ treatment. All the samples showed 100% browning ratio under the $-30^{\circ}C$ treatment. The budburst ratios of leaf buds were 85%, 66%, 32%, and 0% under the -15, -20, -25 and $-30^{\circ}C$ treatments, respectively. The branches of peach fruit treated with the same freezing temperature showed different responses depending on the sampling date. In January the browning ratio was low and the budburst ratio was high whereas in February the opposite was the case, showing vulnerability of peach trees to low temperature after endo-dormancy release.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.93-100
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• 2005

This research was performed to investigate the possibilities of industrial usage of camellia (Camellia japonica L.) by examining the antioxidant and antimicrobial effects of methanol extract with different sections. Content of total phenolics, DPPH radical scavenging activities and antibacterial activity of young leaf, mature leaf, flower bud, flower, bark, and seed of camellia were compared in vitro experimental models. Total phenolics was contained the higher in young leaf (74.62 mg), flower bud (65.02 mg) and flower (62.42 mg) but less than 20.95 mg per 100 g of dry weight in other parts of Camellia japonica L. And effects of antioxidant measured by DPPH radical scavenger activity ($RC_{50}$, reduce concentration 50%), was shown higher $7.16{\sim}18.14\;{\mu}g/m{\ell}$ in methanol extract of young leaf, flower bud and flower than $61.23\;{\mu}g/m{\ell}$ of BHT as a chemical oxidant. Also, the antimicrobial activity of Camellia japonica L. extracts determined using a paper disc method against food-borne pathogen and food spoilage bacteria, the young leaves extracts showed the most active antimicrobial activity against 7 kinds of harmful microorganisms. Flower bud extracts showed the highest antibacterial activity against P. aeruginosa and Enterobacter spp. C1036. In addition, the minimum inhibitory concentration (MIC) of young leaf extract against B. subtillis,S. fradiae,S. aureus,E. coli,P. aeruginosa, Enterobacter spp. C1036, and S. typhimurium were revealed 1 to 15 ${\mu}g/m{\ell}$. As a result, antimicrobial activity of camellia extracts was shown higher gram positive bacteria than gram negative bacteria.