• The Korean Journal of Ecology
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• 제17권3호
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• pp.277-286
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• 1994

The contents of major elements were determined in current-year and previous-year needles and fine roots of pitch pine (Pinus yzgida) at 33 sites in Seoul and its vicinity. Contrary to Ca and Al in needles, N, P, Mg and K contents in current-year needles were higher than those in previous-year needles. The N, P, K and Al contents in current-year needles in Seoul were not significantly different from those in rural areas. In contrast, Ca and Mg contents in needles in Seoul were significantly lower than those in suburbs and rural areas. The N /Ca and N /Mg ratios in needles in urban Seoul were higher than those in rural areas. Mg contents in fine roots in soil of 0-5 cm depth increased along with distance from the center of Seoul, while Al contents in fine root in soil of 5-10 cm depth decreased along with distance from the center of Seoul. Al contents in fine roots in soil layer in Seoul and suburbs were higher than those in rural areas. Al contents in fine roots in litter layer were 1 /3 - 1 /2 times lower than those in soil layer for all areas. A1 content in fine roots in deep soil was higher than that in top soil. Therefore growth decline of pitch pine in Seoul and suburbs was thought to be caused by Ca and Mg deficiency in plant tissues and Al toxicity to fine roots. Abnormal vertical distribution of fine roots of pitch pine in Seoul and its vicinity were interpreted as the result of growth reduction of fine roots by Al toxicity in deep layer of acid soil.

• Journal of Ginseng Research
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• 제16권1호
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• pp.7-12
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• 1992

This study was carried out to investigate the effect of water extracts from 4-, 5- and 6-year old red white ginseng roots on the inhibition of lipolysis in fat cells induced by toxohormone-L which has been known as lipolytic and anorexigenic factors. Toxohormone-L was obtained by partial purification of the ascites fluid from mice which had been inoculated with sarcoma-180. Each water extract of ginseng was effective in vitro against the inhibition of lipolysis induced by the toxohormone-L at the concentrations over 10~100 $\mu\textrm{g}$/ml. At the concentration of 1,000 $\mu\textrm{g}$/ml, the inhibition ratio of lipolysis by the water extracts of 4-, 5- and 6-year old white ginseng roots were 56.3, 59.7 and 59.4%, and those of red ginseng roots were 78.6, 79.1 and 82.5%, respectively, indicating that the 6-year old red ginseng was the most effective in the inhibition of the lipolysis. The total inhibitory activity per gram of ginseng sample was higher in the 4-year and 5-year old white ginseng roots at the concentrations of 100 $\mu\textrm{g}$/ml and 1,000 $\mu\textrm{g}$/ml, respectively, while for the red ginseng it was higher in the 6-year old ginseng than other ages regardless of the reaction concentration. Only once injection of the ginseng extracts(300 mg/ml in saline solution) with 10 ${mu}ell$/g of weight to the mice bearing sarcoma-180 was not effective against the extension of their life spans. On the contrary, the life spans of the mice were rather shortened by the injection of 5-year old white ginseng and 6-year old red ginseng, as compared to that of control.

• Journal of Ginseng Research
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• 제26권3호
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• pp.165-169
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• 2002

Experiments were carried out to select marker for rusty tolerance ginseng root using high rusty degree lines(HRL) and low rusty degree lines (LRL) in ginseng plant. A strong positive correlation was detected between degree of rusty-root in 4-year-root and that in 6-year-root. The contents of phenolic compounds among samples were not different in stele and branch & fine roots. The contents of phenolic compounds of rusty-roots was higher than that of healthy-roots in cortex, but those of high 겨sty degree lines (HRL) were not different compared with low rusty degree lines (LRL) in cortex using same rusty-degree samples. These suggest that phenolic compounds in cortex tissue were not adequate as a marker to select rusty tolerance ginseng roots. The contents of phenolic compounds of rusty-roots were higher than that of healthy-roots in epidermis, and those of HRL were higher than LRL in epidermis using same rusty-degree samples. These suggested that the contents of phenolic compounds in epidermis tissue might be a potent marker to select rusty tolerance ginseng roots.

• Proceedings of the Korean Society of Crop Science Conference
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.351-351
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• 2017

Arbuscular mycorrhizal fungi (AMF) are particular soil fungi that benefit many crops and require a symbiosis with plant roots to survive. In our previous study, there was a positive correlation between AMF root colonization and soybean grain yield in a four-year consecutive winter cover crop-soybean rotational system without phosphorus fertilizer. It is suggested that higher AMF root colonization can be a better solution for improving soybean growth and grain yield in P-limited soil. Our purpose in this study was to test the hypothesis that a P application is the main factor improving soybean growth, P nutrition and grain yield, and the benefit from AMF to soybean P uptake and growth in a P-limited soil. Impact of a P application on AMF root colonization and communities in soybean roots and their potential contribution to soybean growth and P nutrition under a five-year P-unfertilized crop rotational system were investigated over two-years. In this study, four cover crop treatments included 1) wheat (Triticum aestivum); 2) red clover (Trifolium pratense); 3) rapeseed (Brassica napus); and 4) fallow in the crop rotation. The amount of triple superphosphate as a P fertilizer applied rate after cultivation of cover crops was 120 and $360k\;ha^{-1}$ in 2014 and 2015, respectively. Soybean roots were sampled at full-flowering and analyzed for AMF communities using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative real-time PCR (qPCR) techniques. The AMF root colonization in the soybean roots at full bloom stage was significantly influenced by cover crop and P application throughout the two-year rotation. The two-year rotation of different cover crops or fallow impacted the molecular diversity of AMF communities colonizing roots of soybean. Redundancy analysis (RDA) indicated that AMF communities colonizing roots of soybean were significantly different among cover crop rotations. The AMF communities colonizing roots of soybean were clearly influenced by a P application in the two-year trial. Moreover, a P application may have positively impacts on the AMF communities under P-deficit soil due to the continuous cover crop-soybean rotational system without a P fertilizer.

• Research in Plant Disease
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• 제19권1호
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• pp.49-54
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• 2013

Sclerotinia white rot disease was observed on 5 and 6-year-old ginseng (Panax ginseng) roots in Hongchun, Cheorwon, and Yanggu, Gangwon Province, Korea from 2006 to 2010. Symptoms included a brownish watery soft rot of the roots, and black sclerotia were often found on the rotten roots. The causal agent of the disease was identified as Sclerotinia nivalis based on cultural characteristics and sequence analyses of the internal transcribed spacer region of rDNA and ${\beta}$-tubulin gene with 100% sequence similarity. Pathogenicity tests were performed on 2-year-old ginseng roots with mycelium plugs without wounds. A watery soft rot of the roots and black sclerotia were observed 10 days after inoculation. These symptoms were identical to those observed on naturally infected roots. The same fungus was re-isolated from the lesions induced by artificial inoculation. This is the first report of sclerotinia white rot caused by S. nivalis on P. ginseng in Korea.

• Journal of Korean Society of Forest Science
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• 제79권3호
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• pp.309-315
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• 1990

This study was carried out to observe the effects of two soil mixtures, various nitrogen levels, and inoculation with mycorrhizal fungi on the growth of 1-year-old Pinus thunbergil seedlings in pots. The seedlings were treated with various combinations of above factors and grown one more year in pots. 1. Number of short roots, mycorrhizal short roots, height growth, and total dry weight were higher in vermiculite than in sandy loam. 2. 2-year-old P. thunbergii seedlings inoculated with Pisolithus tinctorius mycorrhizal fungi showed significant increase in primary lateral roots, short roots, and total dry weight than those of uninoculated seedlings. 3. The growth of 2-year-old P. thunbergii seedlings was affected by infection with mycorrhizal fungi and nitrogen fertilization of precious year.

• Journal of Ginseng Research
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• 제25권2호
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• pp.101-105
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• 2001

Identification of the age of ginseng root is very important in commercial market as well as in research field. However, any criterion abut it has not been clearly established yet. We studied to find a clear morphological key for identification of ginseng root\\`s age using the histochemical staining method. Fresh sections of 3, 4, 5, and 6 year old roots were stained with 1% nile blue, observed under the light microscopy, and compared each other. The number of secretory duct layers(SDL) is a useful key to confirm the age of ginseng root as follow; three-year-old root has two, four-year-old one has three, fie-year-old one has four, and six-year-old one has five resin duct layers on each cortical region of roots. Secretory ducts are thought to be formed by the vascular cambium every year. Unlike the surrounding parenchyma cells, secretory epithelial cells lack starch grains in the cytoplasm.

• Journal of the Korean Society of Food Science and Nutrition
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• 제40권12호
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• pp.1793-1796
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• 2011

The effects of ethanol extracts from Astragali membranaceus Bunge (AMB) and A. membranaceus Bunge var mongholicus Hisiao (AMBMH) on antioxidant and nitric oxide (NO) production were evaluated. The total polyphenol contents of AMBMH extracts from two, four, and six-year old roots was 45.3, 71.3, and 78.0 mg/g, respectively. These values and those of total flavonoid content were higher than those of AMB extracts. The DPPH radical scavenging activity was the highest in ethanol extracts from four-year old AMBMH roots. The ABTS radical scavenging activity was also higher than those of AMB in ethanol extracts from four- and six-year old AMBMH roots, but not in two-year old roots. The NO production of ethanol extracts from six-year old AMBMH roots was higher than that of two- and four-year old AMBMH roots. However, there is no significant difference in NO production based on the cultivation period of AMB.

• Journal of Forest and Environmental Science
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• 제26권3호
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• pp.193-202
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• 2010

To analyze the effects of tree roots on the stability of damage slope, distributional and physical properties of five-year Pinus densiflora roots were investigated. In the composition of roots, the proportion of main root to lateral root was 1 to 9 in slope condition. Root tensile force was increased in accordance with increased proportion to diameter of Pinus densiflora roots. However, tensile strength was decreased in proportion to diameter of roots. Root shear strength showed that soil containing Pinus densiflora roots was higher than that of non-treated soils. This result shows that Pinus densiflora roots significantly stabilize the surface-soil rather than sub-soil in damage slopes.

• Journal of Ginseng Research
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• 제20권1호
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• pp.72-77
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• 1996

This study was conducted to establish an identification method age for cultivated ginseng (Panax ginseng C.A. Meyer) based on counting the stem vestige at rhizome. Weight, diameters of body and lateral roots, and ratios of those diameters were overlapped with those of other ages, so these are not enough as a criterion for identification of ginseng age. Since the stem vestige at rhizome was remained clearly from the 3rd-year age, root age can be the number of stem vestige +2. The number of stem vestige should be counted at the one side of rhizome with abundant vestige for multi stewed plant. It is necessary that the number of year-ring in root is investigated for rhizome damaged plant, but it must be considered that the new year-ring can be shown clearly after around loth of June. All dormant roots had damaged rhizome by some reasons.