• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.81-88
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• 2011

Effect of concentrations of different plant growth retardants (PGRs) supplied to a recirculated nutrient solution in an ebb and flow system on the growth and development of potted Spathiphyllum 'Top-Pin' and 'Mini' was examined. Plants were planted in 10 cm diameter plastic pots filled with a mixture of peat moss and perlite (1 : 1, v/v) on 30 June 2005 and grown until 23 Sep. 2005. In a closed ebb and flow system, 50, 200, 350, $500mg{\cdot}L^{-1}$ daminozide (B-9), 10, 40, 70, $100mg{\cdot}L^{-1}$ paclobutrazol (Boundy), 5, 15, 25, $35mg{\cdot}L^{-1}$ ethephon (Florel), and 1, 4, 7, $10mg{\cdot}L^{-1}$ uniconazole (Sumagic) were supplemented to a nutrient solution at the initiation of experiment. On every irrigation, the nutrient solution containing PGRs was supplied at a 2 cm depth and kept for 15-20 minutes. The surplus nutrient solution was drained back into the tank for next irrigations. Paclobutrazol gave the most pronounced effect in inhibition of stretchiness. The greatest reduction of leaf length, fresh and dry weights of shoot, and elevated chlorophyll content were recorded in Spathiphyllum, with increasing paclobutrazol concentration. Daminozide concentration greater than $200mg{\cdot}L^{-1}$ resulted in minor stunting. The lowest concentration ($1mg{\cdot}L^{-1}$) of uniconazole showed greater leaf length, leaf width, and leaf petiole length than the control ($0mg{\cdot}L^{-1}$). Uniconazole concentration greater than $1mg{\cdot}L^{-1}$ resulted in similar plant growth as the plant in the control ($0mg{\cdot}L^{-1}$). High concentration ($35mg{\cdot}L^{-1}$) of ethephon resulted in the shortest leaf length, and the greatest chlorophyll content. Inhibition of stretchiness was observed even in the lowest concentration treatments. Among the PGRs, paclobutrazol was most effective in suppressing plant stretchiness. In both cultivars, ethephon and paclobutrazol, but not daminozide and uniconazole, significantly inhibited stretchiness. The results suggested that plant growth retardants (ethephon or paclobutrazol) selected in this study may be used as the most effective agents for inhibition of stretchiness in Spathiphyllum.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.67-78
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• 2017

The purpose of this study was to investigate the effect of humic acid on the germination, the growth and the yield of hot pepper when treated with organic hot pepper seedlings and growing season. The germination rate of 0.05% and 0.1% humic acid was higher than that of untreated, but the germination rates of 0.4% and 1.0% humic acid were 90.0% and 86.7%, respectively, compared with the control treatment (96.7%). At 30 days after transplanting, hot pepper treated with low (0.05%) or high (1.0%) concentration of humic acid decreased the growth of hot pepper seedlings, whereas 0.2% humic acid treatment significantly increased a average height (97.6 cm), leaf number (84.7) and fresh weight ($128.1g\;plant^{-1}$) of hot pepper. After 60 days of treatment with humic acid, the height of hot pepper was significantly longer in 0.2% humic acid. The mean green fruit number of 0.2%, 0.1% and 0.05% humic acid were not significantly different among the treatments, but the mean green pepper number of 0.4% and 1.0% humic acid treatments were the higher with 35.2% and 29.1%, respectively than other treatments. However, the fresh weight of green pepper was found to be $111.5g\;plant^{-1}$ more heavier than the untreated in 0.2% humic acid. The total ($5.8kg\;plant^{-1}$) and average ($1.4kg\;plant^{-1}$) fresh weight of pepper were higher than that of untreated control, except for the 1.0% humic acid treatment after 60 days of soil irrigation. The total weight of hot pepper treated with 0.2% and 0.1% humic acid treatment was $9.3kg\;plant^{-1}$ and $8.6kg\;plant^{-1}$, respectively, which were heavier than the other treatments. The effect of humic acid concentrations on soil microbial populations, pH and EC was investigated. The soil bacterial population density of 0.2% humic acid treatment was 3.5 times higher than that of untreated control soil. As the concentration of humic acid increased from 0.05% to 1.0%, pH and EC of hot pepper grown soil also increased.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.2
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• pp.91-96
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• 2006

This experiment was carried out in order to examine the winterhardiness, heading date, fresh and dry matter yeild of Festulolium braunii, a hybrid of Festuca pratensis and Lolium multiflum, which is newly introduced in Korea. This experiment was performed at National Livestock Research Institute in Suwon and Namwon from September 2004 to July 2005. The results are as follows. 'Fleurial', 'Boxer', and 'Perun' showed stronger winterhardiness than 'Hwasan 101', which is one of the strongest in the winterhardiness hybrids. Therefore, we do not see there is any problem in winterhardiness when these hybrids are cultivated in Korea. The hybrids are turned out to be mid and late maturing hybrid. The average heading dates of the three hybrids were May 25 in Namwon and May 27 in Suwon. These dates are lower($1{\sim}3$ days) than that of Hwasan 101. They showed $91{\sim}96cm$ in leaf length at 1st cutting times which are comparatively long. This experiment also disclosed that their lodging and regrowth are strong and excellent. We also found out that there are significant difference between regions and hybrids in the total fresh yield per ha. The average fresh yield of Suwon was 83,222 kg/ha and that of Namwon was 69,139 kg/ha. We could not see any difference in the dry matter yield affected by region, however, there were significant difference in hybrids(p<0.05). The crude protein contents of the three hybrids indicated very high figures. the crude protein cotents of Perun, Fleurial and Boxer are 18.0% 17.4% and 16.7% respectively. However the ADF (Acid Detergent Fiber) shows $28.1{\sim}29.2%$ which is less contents than 33.2% of Hwasan 101. We found out from this experiment that these three hybrids have excellent feed quality because the NDF (Neutral Detergent Fiber) is decreased by $7{\sim}3.8%$ comparing that the NDF of Hwasan 101 is 58.3%. Also each hybrids contains more crude fat by 1%, a little more chemical composition and less ash contents. Thus we can tern that chemical composition contents of these hybrids are also fittable.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.175-182
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• 2018

Knowledge of the optimum cultivation period for Chinese cabbage would help growers especially in spring in Korea. Growth and yield of Chinese cabbage in a temperature gradient chamber was evaluated for the growing periods of 64 days from three set of transplanting dates including March 6, March 20, and April 3 in 2017. Air temperature in the chamber was elevated step-by-step, by $2^{\circ}C$ above the ambient temperature. This increment was divided into three phases; i.e. low (ambient+$2^{\circ}C$, A), medium (ambient+$4^{\circ}C$, B), and high temperature (ambient+$6^{\circ}C$, C). The fresh weight of Chinese cabbage was greater under B and C conditions in the first period and A in the second period, which indicated that GDDs affected the fresh weight considerably. However, leaf growth (number, area, length, and width) did not differ by GDDs. Bolting appeared under A condition in the first period, which was caused by low temperature in the early growth stage. Soft rot was developed under C condition in the second period and all temperature conditions in the third period, which resulted from high temperature in the late stage. Fresh weight increased when GDDs ranged from 587 to 729. However, it decreased when GDDs > 729. The maximum expected yield (16.3 MT/10a) was attained for the growing period of 64 days from transplanting date during which GDDs reached 601. The GDDs for optimum cultivation ranged from 478-724 under which the yield was about 95% (15.5 MT/10a) of maximum fresh weight. Such an optimum condition for GDDs was validated at five main cultivation regions including Jindo, Haenam, Naju, Seosan, and Pyeongtaek in Korea. In these regions, GDDs ranged from 619-719. This suggested that the optimum GDDs for Chinese cabbage cultivation would range from 478-724, which would give the useful information to expect the cultivation periods for ensuring maximum yield.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.357-362
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• 2012

Proper light intensity, shading tolerance, potting media, and fertilization level were investigated to develop Orostachys iwarenge for. magnus (Korean name, Ullungyeonwhabawisol) as a potted ornamental plant. The plants were grown under different light intensity (52, 82, 90, and 97% shading). The best growth was shown at 52% shading, which indicated that the proper light intensity for O. iwarenge for. magnus is less than 52% of shading. Plant growth decreased severely at 82% shading and leaf color became lighter as the shading rate increased, which indicated that O. iwarenge for. magnus has no tolerance against low light intensity. To select a proper potting media, decomposed granite (DG), fertilizer-amended media (FAM), river sand (RS) were used as potting medium with different ratio of 60:20:20 (DG:FAM:RS, v/v/v), 80:20 (DG:FAM, v/v), 60:40 (DG:FAM, v/v), and 20:80 (FAM:RS, v/v). DG:FAM:RS (60:20:20) showed the highest values in shoot fresh weight, plant width, and number of runner in potted O. iwarenge for. magnus. Fresh weight of shoot part was 16 g in DG:FAM:RS (60:20:20), which was about 2 folds of those at the other medium. At the experiment for selection of proper fertilization level, plants showed a better growth as the concentration of hyponex solution and application frequency increased. Once drenching 1 week interval of hyponex solution diluted by 1,000 folds brought the highest results in fresh weight, plant width, and runner number. Particularly, fresh weight of shoot part was 35 g at once drenching per week of 1,000 folds solution, indicating 84% improvement comparing with non treatment (19 g).

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.318-323
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• 2008

Nokwon, a new cultivar for vegetable soybean, was developed from the cross between Keunolkong and Hyangnam-1 and released in 2006. The pedigree of Nokwon, designated as Milyang 153 in 2003, was SS96425-2B-11-4-1-1-1. Nokwon, used as a vegetable soybean was characterized by dark green pod, large seed, very short plant height, and lodging resistance. Nokwon has determinate growth habit, white flowers, gray pubescence, oval leaf shape and brown pods at maturity. The mature seeds have a greenish yellow seed coat with brown hilum and yellow cotyledon. In Korea, Regional Yield Trials (RYT) for vegetable soybean from 2004 to 2006, Nokwon shows strong tolerance to soybean mosaic virus and lodging in fields. Fresh pods of Nokwon harvested at the beginning of August, and stem height was 11cm shorter than 45 cm of Hwaeomputkong. In the same tests, fresh pod of Nokwon (11.4 ton/ha) yielded 14% higher than Hwaeomputkong (10.0 ton/ha). Nokwon had 5.9 cm fresh pod length, 13.1 mm fresh pod width, 75.4 g seed weight per 100 green seed, 39.4% green seed protein content, and 17.3% green seed oil content.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.684-689
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• 2010

'Sangwon', a new cultivar for vegetable soybean, was developed from the cross between 'Keunolkong' and 'Oshimamidori', and was released at the National Institute of Crop Science (NICS) in 2007. The goal to develop a vegetable soybean cultivar with green pod, early maturity, large seed size, high yield, lodging tolerance, and resistance to disease such as soybean mosaic virus (SMV). 'Sangwon' has light green pod, early maturity, large seed, short plant height, and lodging tolerance. 'Sangwon' has determinate growth habit, white flower, gray pubescence, and oval leaf shape. The matured seeds have a yellow seed coat with light brown hilum, and a yellow cotyledon. 'Sangwon' has 5.8 cm fresh pod length, 13.2mm fresh pod width, 69.5 g seed weight per 100 green seeds, 44.0% green seed protein content, and 14.8% green seed oil content. At the regional yield trials (RYT) for vegetable soybean from 2005 to 2007, 'Sangwon' shows strong resistance to soybean mosaic virus (SMV) and tolerance to lodging in fields. Fresh pods of 'Sangwon' were harvested at the beginning of August. In the same tests, fresh pod of 'Sangwon' (10.39ton/ha) yielded 5% higher than 'Hwaeomputkong' (9.90ton/ha).

• Horticultural Science & Technology
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• v.32 no.1
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• pp.41-45
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• 2014

This study was conducted to investigate the effects of crown numbers on growth and yield of ever-bearing strawberry (Fragaria ${\times}$ ananassa Duch.) 'Goha' cultivar. Strawberry seedlings were planted with $55{\times}30cm$ distance on April 29, and the randomized block experimental was designed by putting the crown numbers by 1, 3, 5 and crown-unremoved as the control. At the early growth stage, as the numbers of crown decreased, the size of leaf became larger and inflorescence diameter became thicker. Plant height became higher as the number of crown increased at the final harvesting time. Fresh weight of crown-unremoved plants was 118 g, showing 77.2 g higher than that of plants with one crown. Numbers of the developed inflorescence of plants with five crowns and crown-unremoved was 20.1, whereas 6.8 of plants with one crown, resulted in 13.3 more crowns. However, crown number did not significantly affect the fruit quality. As the crown number increased, the average fruit weight was lighter and the marketable fruit rate was shown to decrease significantly. The marketable yield of crown-unremoved plants was $17,372kg{\cdot}ha^{-1}$, showing 68% higher than plants with one crown. Therefore, crown management without thinning crowns was recommended and inflorescence thickness less than 3 mm should be removed for successful production of ever-bearing strawberry 'Goha' cultivar during summer season.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.77-80
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• 2003

This study was conducted to determine the optimum organic fertilizer rate (0, 100, 200, 300, 400, 500, 600kg/10a) of worm casting on growth response and yield of Ieol´ radish in Jeiu island. The results obtained were summarized as follows; plant height was getting bigger as organic fertilizer increased from 0 to 500kg/10a and then became smaller at 600kg/10a. But was no significance from 200 to 600kg/10a. Number of leaves, leaf width and root diameter were the same trend with plant height response. Root length was not significantly affected by organic fertilizers. SPAD reading value of leaves increased as increasing of organic fertilizers. Fresh matter yield (top+root) increased significantly 2,949∼4,561kg/10a as fertilizer rate increased from 0 to 200kg/10a, increased 5.096∼5,707kg/10a from 300 to 500kg/10a of fertilizer rate and decreased to 4,873kg/10a at 600kg/10a. Top and root weight were the same trend with fresh matter yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.181-187
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• 2014

Polycyclic aromatic hydrocarbons (PAHs) are a group of ubiquitous hazardous pollutants derived from fossil fuel, various combustion sources and pyrolysis of a wide range of plastics. Because PAHs can be uptake into crop plants, the inhibitory effects on rice and soybean plants were examined in greenhouse and growth chamber experiment. Soil-applied PAHs (phenanthrene of 0, 10, 30, 100 ppm) slightly reduced the plant height and dry weight both in transplanted rice and soybean plant. The inhibitory effect on growth was greater in soybean than rice. Plant height of soybean plants treated by 100 ppm was 58.9 cm and this value was 87.2% of untreated plant. In rice plant, the plant height was less inhibited (96.0% of untreated plant) by 100 ppm at 80 days after treatment (DAT). However, leaf chlorophyll content and chlorophyll fluorescence were less inhibited by PAHs at late growth stage (after heading) although the photosynthesis-related parameters were slightly inhibited from 20 DAT to 70 DAT. In agar medium experiment with infant seedlings, inhibition of seedling length and fresh weight by phenanthrene at 100 ppm were greater as compared to the experiment with adult plant in pot. Seedling length and fresh weight were reduced by 54.2% and 33.3% for rice and 27.9% and 13.2% for soybean, respectively. The results reflected that PAHs were more inhibitory during juvenile stage than adult stage and more inhibitory to rice plant than soybean for juvenile stage.