• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.22-32
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• 1997

This experiment was conducted to obtain information for the cultivation of Korean valerian(Valeriana lauriei var. dasycarpa Hara) which will be useful for medicinal and aromatic resources. The effect of different temperature conditions, light intensities and soil water conditions on growth, yield and component of essential oil of V. fauriei were measured at the Dankook University, Cheonan, and a study on the shading treatment was at Umsung, Chungchongbukdo, and Jinbu, Kangwondo, in 1995. V. laudei was planted at five different temperature conditions, 10, 15, 20, 25 and 3$0^{\circ}C$, eight light intensity conditions, 1, 000, 2, 500, 5, 000, 20, 000, 30, 000, 40, 000, 50, 000 and 60, 000lux, six soil water contents, 30, 45, 55, 70, 80 and 90％ of the saturated soil, during growth stage. Shading treatment was three conditions, 0, 25 and 50％, during the daytime in field conditions. Photosynthesis had a highly significant relationship with temperature conditions in a quadratic regression model, from which the temperature for the plant growth was estimated to be 17.7$^{\circ}C$. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was 20.3$^{\circ}C$. The content of essential oil and extract rate of root was the highest in the 15~2$0^{\circ}C$. Photosynthesis also was significantly affected by light intensity in a quadratic regression model, from which the optimum light intensity for the growth was estimated to be 40, 000lux. Root yield was more produced in Jinbu than that of in Umsung. The root yield was increased by the shading treatment in Umsung, whereas it was decreased by the shading treatment in Jinbu. The content of essential oil was not affected by the shading treatment of plants during the cultivation, while the compositions of components of essential oil were related to the growing locations. As soil water content was higher, the growth and content of root extract were increased. The optimum soil moisture for the growth of V. fauriei was 80~90％ of the saturated soil. In summary, the results indicated that the growth, yield and component of essential oil in V. fauriei were affected by environmental factors as well as soil moisture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.3
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• pp.256-267
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• 1987

Changes of light intensity under and above shading materials were measured at different relative light intensity(R.L.I. 5% of common straw shading, 15% of polyester shading and 20% of polyester shading at 12 o'clock on clear day) and lines(lst, 3rd and 5th lines) on clear and cloudy days in 5-year -old ginseng plant populations. Rates of photosynthesis and respiration, microclimate and root yield were also measured in field. Air temperature of R.L.I. 5% were lower 2$^{\circ}C$ compared with R.L.I. 15% and lower 3$^{\circ}C$ compared with R. L. I. 20% from 12 to 14 o'clock on clear day, but there were not difference among R. L. I. on cloudy day. Relative humidity of R. L. I. 5% were higher 5% compared compared with R.L.I. 20% from 10 to 14 o'clock on clear day, R. L. I. on cloudy day. Light intensity were below 5,000 lux at R.L.I. 5%, about 15,000 lux at R.L.I. 15% and about 20,000 lux at R.L.I. 20% from 10 to 15 o'clock on clear day. But light intensity were below 3, 000 lux at R. L. I. 5% about 10, 000 lux at R. L. I. 15% and about 15, 000 lux at R. L. I. 20% from 10 to 15 o'clock on cloudy. Photosynthetic rate of R.L.I. 15% and R.L.I. 20% were higher compared with R.L.I. 5% on clear and cloudy days. Tatal photosynthesis in a day were increased by R.L.I. 5%, 20%, 15% in turn on clear and cloudy days. R. L. I. 15% and 20% were not notable difference of photosynthetic rates among lines but R. L. I. with R. L. I. 15%, and higher 8% but there were not different among 5% was notable difference of one. Root fresh weight were increased by R.L.I. 5%, 20% and 15% in turn and R.L.I. 15% and 20% were not notable difference of root yield among lines but R. L. I. 5% was notable difference of one.

• Journal of Ginseng Research
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• v.23 no.1 s.53
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• pp.1-7
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• 1999

Photosynthetic rates and leaf bleaching were measured under light of far-red, red, orange, green, blue and white in order to clarify the effect of light qualities on photosynthesis in Panax species, P. ginseng and P. quinquefolium. Photosynthetic rate of P. ginseng and P. quinquifolium showed higher in the order under the light of red > orange > blue > white > green. Degree of leaf bleaching in P. quinquifolium showed severer in the order under the light of far-red > red > white > blue > orange > green. These suggest that shading material with blue or orange color is good for ginseng growth. As for the effect of temperature, the photosynthesis was increased with increasing temperature untill $25^{\circ}C$ and thereafter decreased. Therefore, it was clarified that the optimum temperature for photosynthesis of P. ginseng and P. quinquefolium was $25^{\circ}C$. And the dark respiration rate of ginseng leaf also increased with increasing air temperature. Especially, the dark respiration rate increased by $80\%$ for P. ginseng and by $73\%$ for P.quinquefolium at above $30^{\circ}C$ as compared with $25^{\circ}C$. In general, the photosynthesis rate was higher in P. quinquifolium than in P. ginseng and ranged from 3.54 to 4.04 mg $(CO_2{\cdot}dm^{-2}{\cdot}hr^{-1})$ for P. quinquefolium and from 2.08 to 2.59 mg$(CO_2{\cdot}dm^{-2}{\cdot}hr^{-1})$ for P. ginseng.

• Proceedings of the Korean Society of Crop Science Conference
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• 1996.10a
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• pp.90-91
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• 1996

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.97-102
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• 1999

This study was conducted to compare seasonal changes of height, diameter at root collar, biomass and chlorophyll contents of Abies holophylla seedlings grown in Sangju National University Nursery under different light intensities. Four light intensities were adopted using nylon net such as 100% sunlight(1800 $\mu$㏖ m$^{-2}$ s$^{-1}$ ), 75% of sunlight (1350 $\mu$㏖ m$^{-2}$ s$^{-1}$ ), 50% of sunlight (900 $\mu$㏖ m$^{-2}$ s$^{-1}$ ) and 25% of sunlight (450 $\mu$㏖ m$^{-2}$ s$^{-1}$ ). Planting density in four light intensities was 30 cm$\times$30 cm. In each treatment, 100 trees were planted and height, diameter at root collar, biomass and chlorophyll contents were measured. The highest height, diameter at root collar and biomass in Abies holophylla seedlings were observed at 100% full sunlight. Lowest chlorophyll contents (Chlorophyll a, b and total) were shown at 25% of sunlight, lowest light intensity treatment in this study. Growths and chlorophyll contents of Abies holophylla seedlings were strongly associated with light intensity. Photosynthesis has to be investigated in near future because photosynthesis and chlorophyll contents were strongly related to tree growth with long periods.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.38-45
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• 1982

To determine the optimum light intensity for growth of ginseng plants, change of temperature, moisture content in son, occurrence alternaria blight, defoliation rate, chlorophyll contents, and growth of shoots and roots were investigated under different light intensity such as 5%, 10%, 20% and 30% light transmittance rare(L.T.R.). The results obtained were as follows. 1. Maximum temperature under the shading was increased as the increase of light intensity, whereas soil moisture content decreased 2. As the increase of light intensity, stem and Peduncle length, leaf area, and chlorophyll contents decreased significantly but length and width of the leaf was not significant, while stem diameter, special leaf weight and chlorophyll a/chl. b ratio increased 3. Stem color was shown dark purp!e as the increase of light intensity. 4. Photosynthesis during the day was highest at 9 A.M. and decreased as time passed in all plots. The means of photouynthesis during the day showed in the order of 20%, 10%, 30%, 5% L.T.R., and optimum light intensity for highest photosxthesis was 18.4% L.T.R. by theoritical equation. 5. It was showed a tendency that alternaria leaf blight of ginseng plants was increased as the increase of light intensity. 6. Defoliation rate of ginseng plants was increased as the increase of light intensity, especially all plants were defoliated by late June without shading. 7. Yield percentage of the rear line was increased as the increase of light intensity. Root weight per plant showed in the order of 20%, 10%, 30%, 5% L.T.R., and optimum light intensity for the best yield was 18.5% L.T.R. by theeritical equation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.256-260
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• 2008

This study was conducted to response the photosynthetic rate and anatomical characters in one year ginseng plant against the light transmission ratio (10%, 20% and 30% in natural light) under shading materials by polyethylene (PE) net. The chlorophyll content and the photosynthesis of ginseng according to the light transmissivity showed decreasing trend as the light transmission ratio increased. At the higher light transmission ratio condition, leaves showed the chlorosis due to the physiological disorder, stems formed hypodermis, and phloem development inside the vascular tissue shrunk remarkably. Also, roots showed the epidermis destruction and less cambium development at the higher light intensity. The root weight also decreased as the light transmission ratio increased.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1313-1318
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• 2007

Illicium anisatum was bred under four different light intensity. Those condition were full sunlight(PPFD $1600{\mu} mol\;m^{-2}s^{-1}$), 30% treatment(PPFD $400{\mu} mol\;m^{-2}s^{-1}$), 50% treatment(PPFD $250{\mu} mol\;m^{-2}s^{-1}$) and 70% treatment(PPFD $100{\mu} mol\;m^{-2}s^{-1}$), respectively. Chlorophyll a and b were increased according to decrease of light intensity. Thirty percent and 50% treatment had not significant different in chlorophyll a and b. Thirty percent treatment was shown the best photosynthetic activity through invested photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend of 50% treatment was similar to 30% treatment. Seventy percent treatment was shown the best photosynthetic activity at low light intensity but that was decreased to lower value than 30% and 50% treatment under high intensity. Control, bred full sunlight, was shown the worst photosynthetic activity at measured all light intensity. That result could imply that was caused by photo-inhibition because of long term exposed of shade tolerant plant at high light intensity. Leaf characteristics had not significant different in leaf length, width and area but leaf dry weight had similar trend to photosynthetic activity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.288-294
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• 1994

Seedling vigor of introgressive hybrids between birdsfoot refoil 'MO-20"(Lotus corniculatus) used as the maternal parent and tetraploid(2n=4x=24)accession PI302921 narrowleaf trefoil(Lotus corniculatus L.), and parents were compared in terms of dry matter accumulation , net photosynthetic rate, dark respiration rate, and growth analysis. The hybrids showed better seedling vigor than PI302921 as they had lower dark respiration rate and higher relative growth rate (RGR) than PI302921. Hybrids grew faster than MO-20, but there was not significant difference between them. Net photosynthesis per unit area increased during three weeks after emergence without difference among the entries, then decreased sharply with leaf age and shading marking much differences among entries Dark respiration rate was very high just after emergence, after which it decreased rapidly until it reached a stable level at 1 week through 3 weeks of age, and then dropped again. In general, dark respiration, photosynthesis, and seedling growth of the hybrid was similar to those if MO-20. Although there are some reports about interspecific hybrids of Lotus species, it still remains as a new area for genetic improvement of seedling vigor of L. corniculatus.atus.

• Korean Journal of Medicinal Crop Science
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• v.23 no.2
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• pp.161-167
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• 2015

This study was carried out to determine the effects of light controls and leaf mold on root growth and physiological responses of Atractylodes japonica growing in forest farming. The experiment was performed by light controls (100%, 62.5%, 40.3% and 19.7% of full sunlight) and application of leaf mold to soil. Height, stem diameter, number of flower buds and root collar diameter were the highest in leaf mold within 62.5% of full sunlight (relative light intensity 62.5%). And these were the higher in leaf mold within each light level. As the shading level increased, light saturation point and maximum photosynthesis rate decreased. As the light level decreased, SPAD value increased in control and leaf mold. As a result of surveying the whole experiment, A. japonica was judged worse root growth under the lower light level. It was concluded that the light level was one of the most important factors to produce A. japonica. Also, producing high-quality of A. japonica with the price competitiveness by using leaf mold like the experiment can be an effective way to increase incomes for farmers.