• Journal of Ginseng Research
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• v.17 no.3
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• pp.224-227
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• 1993

Weight (g/root) and bulk density (g/$cm^3$) of tap root in 15-root-grade of 4-year-old white ginseng were investigated by specific gravity and weight-volume method. Bulk density measured by specific gravity ranged from 0.8 to 1.2g/$cm^3$ with almost normal distribution in frequency (number 1 of roots). Bulk density measured by volume-weight method had significant correlation with root weight. The percentage of high bulk density root (above 1.0) showed significant positive correlation with mean root weight or mean bulk density of root weight, indicating that the growth conditions for large root provide the better compactnes of root tissue.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.792-801
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• 1996

A thinning algorithm -based image analysis technique was developed to measure corn root lengths. The root length measurement method was evaluated by comparing thread lengths measured by the image analysis system with actual thread lengths. The length measurement method accurately estimated actual thread lengths (less than 2% calculated error). Also, a rapid root length density measurement procedure, which utilizes the above root length measurement method, was developed to estimate corn root length density without washing the roots. Root length densities estimated from the cut soil surface of core samples taken from the field were paired with the root length densities determined from washed roots from the same soil core sample. A linear relationship between these two values was expected and was found. Eliminating the root washing procedure reduces the time required for measuring corn root length density substantially.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.505-508
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• 2015

Soil bulk density is a key parameter for soil physical property. Much root placed in rhizosphere soil lump, especially in grassland and orchard, makes it difficult to measure soil bulk density. This experiment was carried out to countermeasure the above drawbacks. Volume check apparatus using water-filling method was made of acryl for higher accuracy in bulk density measurement. 10 types of land cover, including bare, tall fescue, rye, and soybean, were used for determining the relationships between root and bulk density. In this study, higher root volume resulted in higher differences in bulk density between in-situ core soil and root-ridded core soil, which indicated the volume check apparatus through water-filling could be useful for increasing the accuracy of bulk density of soils with much root.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.109-114
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• 1991

The depth and spread of root systems and the density of root branching affect the success and survival of plants subjected to drought. The type and size of root systems are controlled by heredity and soil conditions. There are also important interaction between roots and shoots; roots are dependent on shoots for carbohydrates, growth regulators, and certain vitamins, and shoots are dependent on roots for water, minerals, and certain growth regulators. Pinus thunbergii Parlatore had most of roots in the top 20cm of soil, and had little short of roots in the less than 80cm of soil. Average of root density was $270cm/cm^3$ in the upper soil(0~20cm). Root density of Pinus thunbergii Parlatore was similar to that of Cryptomeria japonica. There is no saying that Pinus thunbergii Parlatore has an advantage over Cryptomeria japonica in the drought. This data will be used to the root density values in the simulation model of black pine stands.

• Plant Resources
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• v.4 no.1
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• pp.6-12
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• 2001

Growth and yield of licorice were investigated under the different conditions of ridge height, planting density, and irrigation in order to establish its cultural practices for the domestic production with the aim to substitute the import. Seedlings were grown under low ridge(20cm) and high ridge(40cm) in low density plot(60$\times$30cm) and high density plot(40$\times$30cm), respectively. The low ridge cultivation of large seedlings increased plant height and root length under low density, and stem and root diameter under high density compared to the high ridge cultivation. In the high ridge cultivation, high density plot was 1.1 to 1.3 times in plant height, root length, stem and root diameter as high as low density one. Fresh and dry weight of plant and root in high ridge were 1.3 to 1.5 times as high as those in low one. The growth of small seedlings(4~10g) were generally poor compared to that of large seedlings. High density plot in low ridge showed the good growth characteristics including plant height, root length, stem and root diameter, and number of branch. High density plot was 1.4 to 1.6 times in fresh and dry weight of plant and root as high as low density plot. In the seasonal changes of growth under various irrigation regimes, the twice irrigation a day produced the more number of leaf than the other regimes since around 46 days after transplanting. The former irrigation resulted in 1.2 to 1.4 times in plant height as long as the other irrigations around 26 days after transplanting and then the difference was increased to 1.6 to 2.0 times around 64 days after transplanting. Under the twice irrigation a day, plant height, root length, stem diameter, root diameter, number of leaf, fresh plant weight, dry plant weight, fresh root weight, dry root weight were 1.6 to 2.0, 1.1, 1.2 to 1.6, 1.3 to 1.8, 1.9 to 2.7, 1.7 to 8.0, 1.6 to 2.8,2.0 to 3.0, 1.6 to 2.7 times as high as those under the other irrigation regimes, respectively.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.3
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• pp.97-105
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• 2013

Kalopanax septemlobus (Thunb. ex Murray) Koidz. is natively distributed in Korea. The importance of this species has been increased not only for high quality timber but for medicinal and edible uses. However, increasing market demand of K. septemlobus with illegal cutting and overexploitation has resulted in its rapid depletion and destruction of natural habitat. This study was conducted to understand the survival rate and growth characteristics of planted K. septemlobus seedlings with treatment of root pruning, stem cutting and planting density. The survival rate and growth of height and root-collar diameter for one- and two-year old seedlings with different planting densities were investigated in the clear-cut area of a Pinus densiflora stand for five years. One-year-old seedlings were treated with or without root pruning and planted with three density levels (5,000 trees $ha^{-1}$, 10,000 trees $ha^{-1}$, and 40,000 trees $ha^{-1}$). Two-year-old seedlings were treated with and without stem cutting and planted with the density of 5,000 trees $ha^{-1}$. The survival rate of one-year-old seedlings with root pruning treatment in the density of 10,000 trees $ha^{-1}$ was 92%, while that without root pruning in the density of 40,000 trees $ha^{-1}$ was 67% after five years. The height of one-year-old seedlings has been significantly affected only by planting density in the $5^{th}$ year. The survival rate of the two-year-old seedlings with stem cutting was 75.5% and greater than control (67.3%) in the $5^{th}$ year but no difference in height was shown between the two treatments from three years after plantation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.91-94
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• 2003

Rhizotron technique was used to determine the zone of active root growth in contrasting field situations. The distribution of roots with depth showed most root in the 15∼30 cm layer with fewer in the 0∼15 cm and below 30 cm layer at Lincoln Farm, while root density increased with depth at Winchmore. At Mt Johm (Lake Tekapo) roots were more distributed near soil surface. Root density was increased with fertilizer and irrigation at Mt John. Root number showed the same trends as root length at all lesions. Tube method was good for comparative purposes, and for long-term root growth studies at the same place.

• The Korea Journal of Herbology
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• v.21 no.1
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• pp.79-87
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• 2006

Objectives : Effects of Rhodiola rosea root on cancers on stomach, breast, lung, and liver were examined. Methods : Water extracts and methanol extracts of Rhodiola rosea root were treated on cancer cells, and its effects on cancers were examined. Results : 1. Water extracts and methanol extracts of Rhodiola rosea root was less harmful in its lowest density 0.25 mg/mL (9.l%와 10.5%), but became more harmful as its density increased. 2. As for human stomach adenocarcinoma cells AGS, breast adenocarcinoma cells MCF-7, and lung carcinoma cells A549, methanol extracts showed 70-77% inhibition of cancer cells in high density(1 mg/mL), and water extracts showed 60-70% inhibition rate and its selective death rate was less than 2.5. Conclusion : Rhodiola rosea root can be used to treat cancers and to increase immunity.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.05a
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• pp.34-37
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• 2000

To determine the optimum planting density in Alisma plantago in the southern areas of Korea, Alisma plantago local cultivar was grown under different planting density. The plant height, number of stems and diameter of root were 30cm, 12 and 3.4mm respectively on the planting density, row 20cm $\times$ intrarow 35cm. The fresh yield of root and dry yield of root were 261.2Kg110a, 211.5Kg/10a respectively on the planting density, row 20cm x intrarow 35cm. Therefore, the proper planting density for high yield bumper crop of Alisma plantago for exporting to Japan is planting density with row 20cm $\times$ intrarow 35cm.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.3
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• pp.47-55
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• 2011

Cicada is a very familiar insect to people but habitat characteristics of them are not well known. To investigate habitat characteristics of cicada nymph, plant species, plant cover, soil hardness, accumulated organic mass, organic content in soil, and root density were investigated at 11 sites in an apartment complex garden in Seoul. Selected sites had different densities of cicada nymph case above the ground. Density of cicada nymph case was positively correlated with accumulated organic mass, organic content in soil, and root density and negatively correlated with soil hardness. Even though shrub coverage was not linearly correlated with the density of cicada nymph case, 80% cover of shrub was necessary for the high density of them. Data in this study suggested that organic matter in addition to root density be the primary limitation factor of cicada nymph and high amount of litter-fall decrease soil hardness through the increase of soil organic matter. This study suggests that the density of cicada nymph can be managed through organic content in soil.