• Korean Journal of Plant Resources
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• v.14 no.1
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• pp.1-7
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• 2001

Life form, flower color, flowering and seed-ripening seasons of 59 alpine plants in Paeknokdam, the crater of Mt. Halla, were investigated in order to obtain the information about ornamental potentials of alpine plants. Life form spectrum of alpine plants are characterized by a high percentage of hemicryptophytes (67.8%). This result was similar to those of other alpine plant communities. Flowering season of alpine plants was July to August and seed-ripening season was August to September. Flower color of these alpine plants was dominated by white (27%), blue (22%) and yellow (20.3%).

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.232-236
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• 1997

This experiment was conducted to determinate the optimum harvesting time of Carthami Flos and grain in safflower. In dry Carthami Flos yields harvested at different days after flowering, threre was no significant difference between 2 days and 4 days, however, yield harvested at 6 days was decreased significantly compared with 2 days after flowering. As the harvesting time were delayed, lightness (L') and redness (a') of dry Carthami Flos were decreased but yellowness (b') of that was increased. Color differences (${\Delta}E'ab$) of dry Carthami Flos between harvesting days after flowering were not visible between 4 days and 6 days but between those (4 days and 6 days) and 2 days were visible. As the result, the optimum harvesting time of Carthami Flos was 4 days after flowering. Grain yields and its components were affected by not harvesting Carthami Flos but grain harvesting time. Threre was no significant difference in number of grain per flower head, percentage of ripened grain between grain harvesting time. However, weight of 1000 grains and grain yields increased until 20 days after flowering. As a conclusion, the optimum harvesting time was 4 days after flowering for Carthami Flos and 20 days for grain regardless Carthami Flos harvesting time.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.151-155
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• 2011

The fungus Botrytis cinerea causes fruit rot of strawberry and the damages can result in harvest losses upto 50%. Proper timing of fungicide application is essential for successful control of Botrytis fruit rot, fenhexamid plus iminoctadine tris, cyprodinil plus fludioxonil, fludioxonil alone, and Bacillus subtilis QST713 were applied to individual buds, flowers, and green and red fruit of cultivar 'Seolhyang' ex vivo. Cyprodinil plus fludioxonil or fludioxonil alone was applied i) before and after a 5-hr period of low-temperature ($0^{\circ}C$) incubation ex vivo ii) in field trials. Strawberry flowers and red fruit were more susceptible to B. cinerea than the green fruits. Incidence of Botrytis rot with fenhexamid plus iminoctadine tris and cyprodinil plus fludioxonil was the lowest at flowering, whereas B. subtilis QST713 did not significantly among treatments. In 2010, incidence of Botrytis fruit rot was significantly reduced when fludioxonil was applied two times at 1 week intervals from 50% bloom in field trials. Cultivars Redpearl and Seolhyang were more susceptible to low-temperature than cvs. Maehyang and Akihime. Cyprodinil plus fludioxonil application was effective when applied before onset of the low-temperature treatment period. Fludioxonil showed the most effective when it was sprayed one and more than two times in before and post low-temperature condition, respectively. These results demonstrate that fungicide selection and timing can interact with stage of fruit development and low-temperature in determining effectiveness of suppression of Botrytis fruit rot.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.33-37
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• 2010

Effects of cutting time of double flowered Hydragea serrata for. acuminata native to Korea on flowering and growth of following year were investigated in order to develop as a pot plant. Cuttings were carried out every 10th day from April to September in 2008. The cuttings were directly placed in 15 cm diameter pots. Longest plant was obtained from May cuttings and their average heights were 31.7 cm, and followed by April and July cuttings. Plant heights of August and September cuttings were 23.6 cm and 22.0 cm, respectively. In contrast, growth and height of June cutting were abnormally small. Leaf length, leaf width and petiole length of August and September cutting were reduced, but numbers of leaves were not changed. Average flower cluster numbers of May cuttings were 4 flower clusters, and July, August and September cuttings were 3 clusters while only 1 flower cluster per a plant was obtained during June. Biggest diameter of flower crown was observed from May cuttings and the size was 10.3 cm diameter; however, smaller flower crown size was observed after July cuttings. The best overall flower appearance was observed from May cuttings, and the worst was June cuttings. Even though plant height of August and September cuttings were reduced, flowering aspect and ornamental value were normal, but blooming times were retarded according to late cutting time.

• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.43-47
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• 1975

Forecasting of emergence period of the pine gall midge (Thecodiplosis japonensis U. et I.) is important for the chemical control of the pest. In order to determine the phenosignal of the emergence period of the pine gall midge, the flowering time of black locust (Robinia pseudoacacia L.) at Seoul, Gwangnug, Jounju and Gyungju districts in Korea was investigated. 1. The emergence period of the pine gall midge lasted from end of May until end of June. The emergence of the pine gall midge coincided with the beginning of flowering of black locus at every districts in Korea. 2. The peak of emergence of the pine gall midge lasted from the full blooming period until the end of the flowering period of the black locust. 3. The period of adult emergence of pine gall midge was also found to be associated with the full blooming period of Viburnum sargentii (Caprifeliaceae). Rosa mulliflora (Reseaceae) and Iris ensata (Iridaceae) at Seoul in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.146-150
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• 2011

A large amount of nitrogenous compounds are found in burley tobacco and are responsible for peculiar aroma during smoking. Excess in nitrogen or its compounds such as total nitrogen and proteins in burley tobacco gives a strong pungency and make its taste bad. The present study has focused on improving quality of Burley tobacco by regulating topping and harvesting time of leaf to reduce nitrogen compounds in Burley tobacco. In addition, the early-stage of flower topping had lower level of nitrogenous compound, such as total nitrogen and protein nitrogen, and total tobacco-specific nitrosamine (TSNA) contents compared to the button-stage and full flower-stage topping. Also, the contents of nicotine got significantly decreased while the ether extract was increased as the period of topping got delayed. Regarding the brightness among the colors of cured leaves, the color at the full flower-stage topping was the brightest, and there was no particular difference in red and yellow colors. The harvesting amount was decreased as the period of topping got delayed and there was no significant difference between the topping treatments in terms of the exterior quality. As the harvesting time delayed, the total nitrogen, protein nitrogen, nitrate nitrogen, and ammonium nitrogen were decreased while the nicotine contents got increased. Also, the total TSNA contents were decreased as the harvesting time delayed. However, ether extract was increased. Among the colors of cured leaves, the brightness and degree of yellow color were significantly increased as the harvesting time delayed, and there was no particular difference in the degree of red color. The harvesting amount was decreased along with the delayed harvesting time; however, the harvest of the matured and mellow leaves was higher in terms of price, compared to that of the immature leaves. For the reduction of nitrogenous compound and TSNA contents in Burley tobacco, the topping was examined to be more effective in terms of improvement in chemical contents and quality regardless of the decreased harvesting amount.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.72-75
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• 2018

This study was conducted to investigate changes in the functional compounds in bitter gourd (Momordica charantia L.). Four treatments were used to analyze vitamin C, momordicin, K, Mg, and Ca compounds in Dragon bitter gourd on the 7th, 14th, 21st, and 28th days after pollination. According to the number of days after pollination, level of chemicals containing vitamin C in bitter gourd appeared to decrease continually after pollination, and was the highest, being 74.7 mg/100 g on the 7th day. The level of momordicin, an anti-diabetic was significantly higher in the 7th-day product than that of the 14th day;, meanwhile, there was no significant difference in Ca compounds. These phenomena are considered to fasten the stages of harvest for effective use of functional ingredients in bitter gourd fruits.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.436-441
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• 1985

The study was conducted to provide basic information to breeders and agronomists working with sesame. The grain weight and germinability were investigated for eight plant types classified by branching habit, capsules per axil, and carpels and loculi of a capsule. Two typical cultivars were chosen for each plant type among 527 gene pools. Dry weight of one thousand grains was increased rapidly from 25th to 35th day after flowering, and reached peak on 40th day after flowering in upper part capsules and 45th day after flowering in lower and middle part capsules, so that this period was considered to be of physiological maturity in each capsule bearing part. Side capsules on main stem and branch capsules were lighter than central ones of main stem, and upper capsules of four carpels eight loculi type decreased more seriously. BTB type demonstrated relatively better growth compared to the growth of BTQ type in one thousand grain weight. The maximum grain filling duration for germination percentage increased rapidly up to 40th day after flowering. Above 70% germinability was obtained from 40th day after flowering. Harvesting time of physiological maturity was considered to be 45th day after flowering with peaks of 2.14g of one thousand grain weight, 26% of grain water content and 90% of germinability.

• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.136-146
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• 1993

In order to study flowering of Chrysanthemum coronarium, several investigations on the daylength, shading, irrigation and plant growth regulator treatment were carried out. As daylength was treated for 12, 14 and 16hrs, flowering was accelerated and plant height was increased. Leaf number, length and width were decreased by the increased daylength. Sensitivity to daylength and flower development were accompanied by the plant growth, especially the effect of long day treatment was appeared remarkably when the number of leaves was more than 8 leaves. The minimum days of long day treatment for flowering was more than 10 days. Flowering was delayed by 65% shading treatment, over irrigation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.1
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• pp.1-12
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• 2022

Tilia amurensis is an important honey plant. As T. amurensis mainly distributes mountainous area with various elevations in Korea, accurate prediction of blooming time at the different elevation would benefit forest beekeepers. In this study, we measured time-dependent blooming progress of T. amurensis in Mt. Gariwang area ranging from 500-1500m. Additionally we collected blooming data from web and published literatures and estimated the variation of blooming time relative to the geographic locations. Flowers began to bloom from July 6 to July 22 with full blooming on July 14 in location where elevation is 638m in Mt. G ariwang area in 2021. Based on these databases, a growing degree day (G DD) model was developed for prediction of T. amurensis blooming progress using average daily temperatures. Using the starting date of G DD accumulation of January 1 and base temperature of 5 ℃, blooming period ranging from 10% to 90% of cumulative blooming rate was estimated as 860-1198 degree days (DD). This corresponded to the beginning to the end of July in Mt. Gariwaning area in 2021. This model could explain the phenological variations of T. amurensis flower blooming possibly affected by elevation within geographic area, latitude or year relative to the climate change, and aid forest beekeepers for better timing of nectar foraging by honey bees.