• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.116-122
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• 1998

This study was conducted to investigate growth and flowering of hydroponically-grown carnation as affected by substrate and planting date, Three substrates, coir, perlite, and coir＋perlite(1：1. v/v), and two planting dates. May 1 and September 1 were used. Plant height and stem diameter at harvesting time of cut flowers were greater for the September 1 planting than for the May 1 planting. The plants planted on May 1 produced flowers with weak stems and short stem lengths. In addition, flower weight and blossom width were gloater for the September 1 planting than for the Mar 1 planting. The planting date had no significant effect on the number of petals, The carnation planted on May 1 flowered 50 days earlier compared to those Planted on September 1. Plant height and number of petals were the greatest in the plot of coir substrate. The results indicated that for commercial production of cut carnations in a hydroponic system, planting on September 1 is better than May 1. In addition. the results confirm that coir is the superior substrate for the production of cut carnations in a hydroponic system compared to either Perlite or coir＋perlite mixture.

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.24-33
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• 1989

This study was conducted to investigate the effect of paclobutrazol [(2 RS , 3 RS )1-(4- chlor-ophenyl )-4, 4- dimethyl -2- (1, 2, 4- triazol -1- yl )- pentan -3-01] on the tolerance of hi-gh temperature and drought stress as related to growth retardation , iranspiration rate , soil water content , nitrogen level and photosynthetic rate in perennial ryegrass ( Loliurn perenne L . ' Omega H , ). Plants were given a 30 ml soil drench of paclohutrazol at the concentrations of 0, 0.01, 0.1, 1.0, 10.. 0, mg / 6 .5cm- diameter pot . The rcsults were as follows : 1. Increasing concentrations of paclohutrazul reduced plant height , leaf area , fresh weight and dry weight , hut increased chlorophyll content per unit area . The number of tillers and leaf width were not affected hy the paclobutrazol concentrations . 2. The proper concentration of paclohatrazol on growth retardation in perennial ryegrass was about I mq /pot , hut leaf deformity and severe growth retardation were shown at high concentration of 10 mq / pot . 3. Perennial ryegrasses grown at 30˚C were shown significantly short plant height and low leaf nitrogen level compared with those grown at 20˚C. Increasing concentrations of paclohutrazol at 20˚C increased nitrogen level hut it could not increase nitrogen level at 30˚C . 4. During the drought stress , increasing temperatures significantly promoted transpiration rate and wilting time . It took about 5 days at 20˚C and 3 days at 30˚C to reach wilting time of leaves from water stress treatment . Soil water contents at wilting time of non-treated controls were averaged 6. 871% at 20˚C and 6. 17% at 30˚C 5. Paclohutrazol reduced transpiration rate at high temperature and drought stress . Wilting appeared at the lower water content of soil according to increasing concentrations of paclobutrazol at 30˚C hut there were no differences among concentrations of at 20˚C. 6.Paclohutrazol treatment at 1 rag /pot reduced injury rate of leaves from 67.1 % and 100 % in control plants to 15.7% and 80% at 20˚C and 3010, respectively. 7. Photosynthetic rate per unit area was significantly reduced at high temperature . Paclohutrazol stimulated photosynthetic rate with increase of concentrations at 20˚C but there was no increasing effect at 30˚C.

• Journal of Life Science
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• v.11 no.2
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.

• Molecules and Cells
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• v.37 no.2
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• pp.109-117
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• 2014

Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.3
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• pp.4483-4491
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• 1977

The results obtained are as follows; 1. The variation of the temperature in a vinyl house without heating system is similar to that of air temperature in a day. The difference of maximum temperature and minimum one in a day is 27$^{\circ}C$ which is two times greater than the daily difference of air temperature. 2. When the length of the duct is increased, the high temperature zone is built up in the direction of warm air discharge from the duct, and the low temperature zone is built up in the opposite direction of warm air discharge. But, in case of the duct length is short (0.05 L), the temperature distrubution in a vinyl house become uniform. It is concluded that the shorter length of the duct, the better the distribution of the temperature in a vinyl house is. 3. When the duct is installed at high position, the high temperature zone is built up in the upper zone of the vinyl house and the low temperature zone is built up in the lower zone. And when the position of the duct is low, the rate of temperature variation along the vertical direction become high, and the direct contact of warm air with the plant in the house is occured. It is concluded that the duct should be installed at the position of slightly higher than the plant height. 4. When the fuel consumption rate is fixed at the 101/hr, the lowest temperature warming rate in the vinyl house is 5$^{\circ}C$ without regard to the air temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.2
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• pp.35-41
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• 1979

To observe the effects of temperature and photoperiod on the growth and yield of winter wheat (Triticum aestivum, L) eight varieties including Chang Kwang were tested at various treatments like longday-high temperature (24hrs-20\circ), shortdayhigh temperature (12hrs-20\circ), longday-low temperature (24hrs-14\circ) and shortday-low temperature (12hrs-14\circ). Among the traits measured, days to heading, plant height, spike length, number of spikes per hill and grain yield per hill were generally decreased at high temperature and long day treatment and increased at low temperature and shortday condition. Number of grains per spike was decreased at low temperature and short day condition while increased at longday and high temperature conditions. Grain weight was decreased significantly at high temperature and shortday while increased at low temperature and longday treatment.

• Magazine of the Korean Society of Agricultural Engineers
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• v.23 no.2
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• pp.35-44
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• 1981

This experiment was conducted to find out the consumptive use of irrigated water for calculation of duty water in paddy rice. Tall statured Japonica rice varieties, Nongbaek (early), Jinheung (medium) and Akibare (late), and short statured Tongil typed varieties, Josaeng Tongil(early), Suweon 264 (medium) and Suweon 258(late) were planted on the experimental farm of Kon-Kuk University in 1979. The results obtained in this study were as follows: 1. During the experimental period, the daily mean temperature was almost similar, the relative humidity was higher as much as 2.8%, the amount of rain fall was 100mm less and the pan evaporation was 70mm less compared with those of 30 years average, respectively. 2. The paddy soil was silty loam, which was suitable for the rice cultivation. 3. Varietal differences were find out for plant height, culm length, number of tillers, number of panicles, heading date, matured grain ratio, 1000-grain weight and rough rice yield. This difference might he the cause of varietal difference of the consumptive use of irrigated water during the rice growing period. 4. The evapotranspiration was gradually increased after transplanting and showed the peak from booting to heading stage of rice varieties. The average evapotranspiration through the whole growing period was 5.67-5. 80mm/day for tall statured Japonica varieties, and 5.99-6. 39mm/day for short statured Tongil typed varieties. 5. The ratio of evapotranspiration to pan-evaporation through the whole growing period was 1.49-1.50 for Japonica varieties, and 1.60-1.66 for Tongil typed varies. 6. Average amount of percolation in paddy field was 3. 62mm/day through the whole growing period of rice plant. 7. K-value in Blaney & Criddle formula was 0.94-0.98 for Japonica varieties and 1.02-1.08 for Tongil typed varieties, and coefficient consumptive water use (Kc-value) was 0.95-1.02 for Japonica varieties and 1.04-1.12 for Tongil typed varieties in this study. The modified coefficient for consumptive water use, which was calculated from data collected through the country including this study, was as follows;

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.442-448
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• 1993

The aims of the work were to examme the variability induced by EMS (ethyl methanesulfonate) mutagenesis of soybean plants, and to isolate mutants altered in nodulation and other growth characters. Seeds of two soybean cultivars, ‘Hwanggeumkong’ and ‘Baegunkong’ were treated with 30 and 50mM EMS(pH 7.0) for 6 hours and were planted directly in the field. Field emergency of$M_1 seed was averaged to be 61.0%, and frequency of plants with chlorophyll-deficient sectors of the first trifoliolate is about 0.7%. Regardless of varieties and does of EMS, $M_1 plant injury at harvest was present in plant height, pod and seed number per plant when compared to those of original-type soybean plants. The $M_2 variability of nodulation process induced by EMS treatment was found to be narrower than that of shoot dry weight. On the basis of the occurrence of chlorophyll-deficient plants, mutated cell frequency within $M_1 seed ranged from 5.3% to 84.2%, suggesting that mutation frequency on the $M_1 seed induced by EMS occurred partly and randomly regardless of varieties and doses of EMS. The putative mutant, which had more nodulation than original-type plant, was short in plant height. Sparse-nodulating soybean mutant was lower in leaf chlorophyll content and showed reduced growth.

• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.16-24
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• 2018

This study was investigated to select superior population and clones of Salix gracilistyla for promoting woody biomass resources through creating of short rotation coppices (SRC). Plant materials were collected from seven different population groups of S. gracilistyla and planted at two different nursery sites in Chuncheon and Yongin. Height and root collar diameter showed statistically significant differeces among population, nursery, and annual growth for three years (p<0.01). Aboveground biomass was harvested to investigate dry weight after 3 years from planting, the Youngwol population showed the highest yield as $4.8kg\;DW\;plant^{-1}$ in Chuncheon nursery which was more than double yield compared to the other nursery planted plants. However, Hongcheon and Wonju populations as $3.3kg\;plant^{-1}$, showed the best yield in Yongin nursery. In addition, there was a significant difference between collected populations and nurseries. But there was statistically significant different interaction between population (Pop) and nursery (Nur) (F value = 3.51, p<0.01). Therefore, the superior populations selected by this experiment could be cultivated as an excellent variety for woody biomass resources through the clonal test.

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.23-27
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• 1976

Screenhouse experiments were conducted to find out the varietal difference in ovipositional preference of the striped rice borer moths (Chilo suppressalis W.) on eight varieties of rice and its association with several plant morphological characters. The results indicated the strong preference of the moths for ovipositing on several varieties. The varieties Tongil (Suweon 213-1), Yushin, Jinheung and TKM-6 had comparatively more egg masses and more eggs than the varieties IR-26, IR-747, Rexoro and Juckna. The strong ovipositional preference of moths of Tongil, as compared to the resistant variety TKM-6 and the susceptible variety Rexoro, was. always consistent in this study whenever the number of tillers were uniformed and each two varieties were paired. It could be concluded that the moths definitely preferred Tongil among the test varieties. There was not any significant correlations between the ovipositional preference and the plant characters; such as number of tillers per plant, plant height, external diameter of stem, and size of leaf. The cause of strong perference of the moths for ovipositing on short type varieties Tongil and Yushin were still suspectable.