• Korean Journal of Weed Science
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• v.14 no.1
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• pp.34-41
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• 1994

To better understand the allelopathic effect of sorghum(Sorghum vulgare L.), the inhibitory activities of water extracts of the stem, leaf and root, and of residues of the stem to major crops and weeds associated with them were evaluated. The allelopathic activity of sorghum plants was species specific, and depended on source and concentration. Germination, and shoot and root length of all test species were inhibited by the different concentrations of the stem extract. Among the crop species, radish showed the most inhibition, followed by wheat and rice. Maize was the least sensitive species. Of the weed species, Ipomoea triloba was most inhibited, followed by Echinochloa colona and Rottboellia cochinchinensis. The water extracts of leaves, stems, and roots significantly inhibited germination and seedling growth in E. colona and radish. The stem extract gave the greatest inhibitory effect on E. colona while all three extracts produced similar response in radish. In the greenhouse trial, sorghum stem residue placed on the soil surface as mulch significantly inhibited seedling growth in E. colona and radish, but not that in rice.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.149-154
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• 1990

Various rates of 2, 4-2 were sprayed on 2 and 3 year old ginseng plants as fouler spray to define the critical concentration. No apparent plant injury was noticeable for those ginseng plants when application concentration of 2, 4-D doubled the recommended dosage (70 mil 10a). Neither abnormal fouler change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2, 4-D concentrated two times of the recommended dosage. When the rates of 2, 4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2, 4-D application and plant growth was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2, 4-D, how- ever the ginseng plants produced 0.03 to 0.09 ppd ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 2i-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2, 4.D fouler application but it was recovered 4 weeks after 2, 4-D fouler treatment. The herbicide 2, 4-D was appreciated to 2, 3 and 4 years old ginseng plants as fouler spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2, 4-D on the plant growth and root yield of the ginseng, There were no significant differences in the leaf and stem growth between untreated and 2, 4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2, 4-D. The root weight of 4 years old ginseng plant was not reduced b). application of 2, 4-D concentrated 2 times of the recommended dosage. Application time of the herbicide 2, 4-D had no effects on the leaf or stem growth of 2, 3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2, 4-D, detrimental phenomena as stem bending and deceleration of seedling leaf margin occurred, but stem bending was recovere d in a few day.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.291-296
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• 1990

Various rates of 2,4-D were sprayed on 2 and 3 year old ginseng plants as foliar spray to define the critical concentration. No apparent plant injury was noticable for those ginseng plants when application concentration of 2,4-D doubled the recommended dosage (70 ml/10a). Neither abnormal foliar change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2,4-D concentrated two times of the recommended dosage. When the rates of 2,4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2,4-D application and plant you was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2,4-D, however the ginseng plants produced 0.03 to 0.09 ppm ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 21-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2,4-D foliar application but it was recovered 4 weeks after 2,4-D foliar treatment. The herbicide 2,4-D was applicated to 2,3 and 4 years old ginseng plants as foliar spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2,4-D on the plant growth and root yield of the ginseng. There were no significant differences in the leaf and stem growth between untreated and 2,4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2,4-D. The root weight of 4 years old ginseng plant was not reduced by application of 2,4-D concenrated 2 times of the recommended dosage, Application time of the herbicide 2,4-D had no effects on the leaf or stem growth of 2,3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2,4-D, detrimental phenomena as stem bending and docoration of seedling leaf margin occurred, but stem bending was recovered in a few day s. Keywords Panax ginseng C.A. Meyer, 2,4-D , herbicide.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.157-162
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• 1987

The study was carried out to investigate the effects of light intensity, temperature and seasonal trends on the photosynthesis as well as the physiological characteristics of Panax species and cultivars. Four-year-old plant of Violet-stem variant, Yellow-berry variant, Mimaki and Russian ginseng of Panax ginseng C. A. Meyer and American ginseng of Panax quiquefolium L. were used for study. These Panax species and cultivars were cultivated under the straw shading. The light saturation point of leaves in Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 15,000 lux, but that of Russian ginseng was 10,000 lux. The optimum air temperature on the phtosynthesis of Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 20$^{\circ}C$ but that of Russian ginseng was 15$^{\circ}C$ under 15,000 lux. The photosynthetic rates were increased in order of Russian ginseng, Mimaki, Yellow-berry variant, Violet-stem variant and American ginseng. The respiration rates of ginseng leaves were increased according to the increasing of temperature, but it was not different among Panax species and cultivars. Stomata frequency of American ginseng was highest, that of Russian ginseng lowest, while the length of stomata was reverse. The total chlorophyll content of American ginseng and specific leaf weight of Mimaki were higher than other ginseng cultivars. The root weight of American ginseng was heavier than others, but that of Russian ginseng was lighter. The num ber of leaflets per plant of 2-year-old plant and the root weight of 6-year-old plant were increased in order of Russian ginseng, American ginseng, Mimaki, Yellow-berry variant and Violet-stem variant.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.525-530
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• 1998

These studies were carried out to select the active grow hairy root lines induced from various ginseng(Panax ginseng C. A. Meyer) parts. Hairy roots were induced in root explants, stem and petiole in vitro by A. rhizogenes R1000 or A. rhizogenes $A_4$. These hairy roots could be grown on the phytohormone free medium, and PCR analysis of rol C and vir C gene fragments confirmed that hairy roots were transgenic tissues. We have selected 11 hairy root lines with active growing characters among 300 hairy root lines selected based on growth and morphological characteristics on 1/2MS solid media with 250 mg/L carbenicillin. Morphological characteristics of selected 11 hairy root lines were thickness and thiness of main roots, and many projection for lateral roots, active grow of lateral roots. Among selected 11 hair root lines prominent characteristics of hairy roots with active growing characters were thiness of main roots and active grow of lateral roots. But characteristics of low growing hairy roots were thickness of main roots and low grow of lateral roots. Finally we have selected actively growing hairy roots, KGHR-1, KGHR-5, KGHR-8 among 11 hairy root lines.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.425-430
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• 1987

The present experiment was carried out to investigate the effects of direct sowing time and transplanting culture of Sculellaria baicalensis GEORGE on the grows, the yield and it's components. The results obtained are summarized as fallows; The number of days from seeding to emergence was recognized lineary negative correlation between seeding dates and transplanting dates. Plant height was longest on Apr. 15 Seeding and Apr. 1 transplanting, and was short in the early seeding and transplanting, and the late seeding and transplanting. Stem diameter was thickest on Apr. 15 seeding and Apr. 1 transplanting, and was thin in the early, and the late seeding and trasplanting. Length and dry weight of root were increased on Apr. 15 seeding. In the transplanting date, Length and dry weight of root were increased on Apr.1. Yield of dry root was highest in Apr. 15 seeding date. In the transplanting culture, yield of dry root was highest in Apr.1.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.30-35
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• 2004

Compositae plants are known to contain biologically active substances that are allelopathic to agricultural crops as well as weed species. Aqueous extracts from leaves of Xanthium occidentale were assayed against alfalfa (Medicago sativa) to determine their allelopathic effects, and the result showed that the extracts applied onto filter paper significantly inhibited seed germination as well as root growth of alfalfa. Untreated seeds germinated in 60h, but extract concentrations greater than 30g $\textrm{L}^{-1}$ delayed seed germination. The extracts significantly inhibited seed germination of alfalfa, and $\beta$-amylase activity of alfalfa and barley seeds during 24-36 hours after treatment. Aqueous extracts of 40 g $\textrm{L}^{-1}$ from X. occidentale were completely inhibited the hypocotyl and root growth of alfalfa. Aqueous leaf extracts showed the highest inhibitory effect and followed by root and stem extracts. Early seedling growth of both alfalfa and barnyard grass (Echinochloa crus-galli) was significantly reduced by methanol extracts. By means of high-performance liquid chromatography, chlorogenic acid and trans-cinnamic acid were quantified as the highest amounts from water and EtOAc fractions, respectively. BuOH and EtOAc fractions of X. occidentale reduced alfalfa root growth more than did hexane and water fractions. The findings of the bioassays for aqueous or methanol extracts reflected that the inhibitory effect of extract was closely related to the level of responsible allelochemicals found in plant extracts.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.13-19
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• 2000

This study was aimed to investigate the effect of several stimulatory trements of flower and seed growth on the reproductive and vegetative growth of Tilia amurensis RUBP. The effects of mounded planting, girdling, root-pruning, bending and foliar fertilizer application on the fifteen to forty yead-old tress growing in the experimental plantation at the Konkuk University and the National forest at the Daegwanryung were measured. The following results were obtained: (1) The number and the longitydinal growth of internode were reduced by the treatments. The xylem growth of the longitudited more greatly than the bark growth by all the treatments. (2)The increasong rate of the brand angle as compared to that of the control was 2.11% in the girdling treatment, 31.61% in the mounded planting treatment, and 22.14% in root-pruning treatment. (3) The foliar application of fertilizer(N, P, K, and B) before flowering increased leaf and stem growth, that one after pollen fertilization increased the fruit growth. (4)The foliar application of fertilizer before flowering increased the xylem growth while that after pollen fertilization increased the bark growth. (5)The stimulatory effects of root pruning and branch bending on the flowering and seed growth were shown relatively less than that of mounded planting. The effect of the moinded planting on the yield of the seeds has remained continuously every year since planting the trees.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.329-332
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• 1996

This experiment was carried out to investigate the growth characteristics and root yield with different harvesting times in Astragalus membranaceus. The growth of stem diameter. number of nodes. number of branches and dry weight of top plant were not affected in late harvesting time compare to early harvesting time. but stem height was increased by harvesting time. Otherwise root growth were effected by harvesting time in one and two years old plant. So, root length, weight of dry root and dry root yield were the most excellent until reached up to harvesting of 10th November. The content of methanol extract was not different between one and two years old plant, but that of different harvesting time was the most by harvesting time in mid November. It was suggested that the optimal harvesting time seems to be in mid November rather than in mid or late October.

• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.26-31
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• 1996

A sesquiterpene ortho-naphtpoquinone was isolated from the 80% aqueous methanolic extract of root bark of Ulmus davidiana Planch whose stem and root bark have been used as an oriental medicine for the treatment of edema, mastitis, gastric cancer and inflammation. On the basis of spectral data obtained from UV-vis, IR, HR-EIMS and NMR spectrometry, including the pulse field gradient (PFG) HMQC and HMBC techniques, the structure of this compound was determined as 2,3-dihydro-3-hydroxy-3,6,9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione which has been known as mansonone 1. This compound has been isolated only from the heart-wood of Mansonia altissima Chev, a Sterculiacea from West Africa. Thus, this compound was isolated for the second time from natural source in this study. This is the first report to present the carbon chemical shift assignment of mansonone I.