• Journal of Environmental Science International
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• v.12 no.11
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• pp.1189-1196
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• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.709-717
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• 2013

The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.54-61
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• 1997

This study has conducted to analyze the crelationship among soil properties and to investigate how they affect soil physical characteristics and plant growth. The experiment of woody plant growth was conducted as follows : Type I was the original soil. Type II, the soil particles smaller than 20${\mu}{\textrm}{m}$ was removed from the original soil. Type III, the soil particles is smaller than 75${\mu}{\textrm}{m}$ was removed from original soil. Wisteria floribunda A.P.DC and Celtis sinensisi Pers. were used for plant growth measurement. 1. Soil type II. the closest to Fuller's curved line, showed high dry bulk density and low in soil pores and saturated hydraulic conductivities. This created poor soil aeration and limited space for the root to growth. When the root did not have sufficient space to grow, there was a lot of physical stress, which hindered the root growth. 2. Soil typeIII was high saturated hydraulic conductivity and a lot of soil pores larger than 10 ${\mu}{\textrm}{m}$. As a result, there were more available spaces for root to spread. It was considered that there was less physical stress for root growth. Therefore, soil typeIII showed significantly greater root growth. 3. Because soil type III has less small particles and saturated hydraulic conductivity was high, and water infiltrates rapidly into the underground when there was rainfall or irrigation. The soil typeIII becomes much stronger soil mechanically due to the less small particles. Therefore, soil typeIII was a suitable material for applying on planting sites where soil compaction is expected.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.38-43
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• 1998

This study examined root growth and distribution under the direct seeding of rice cultivars developed in Korea, Japan, and the U.S. Cultivars from the U.S., especially 'M202' and 'Caloro', had a high ratio of the dry matter partitioning for root and top plant components. Caloro had high root and top growth. 'Koshihikari' from Japan showed the lowest ratio of R/T (root/total dry matter) due to the small amount of root and top plant growth. Most Japanese cultivars except transplanted 'Hatsuboshi' showed low ratio of R/T. Patterns of root distribution for each soil block were recorded by the root box-pin board method. Roots of all cultivars were distributed in blocks A, C, and E in the middle of box, i.e., just below the plant base. Roots of 'Dongjin', M202, and Caloro were distributed deeper than the others. Roots of transplanted Hatsuboshi developed much better than direct seeded Hatsuboshi. Total root weight density was highest in Caloro followed by Dongjin, 'Gancheok', 'Calrose', and the others. The root density of Caloro was twice as much as those of the others except Dongjin. According to cumulative percentages of root distribution on each soil layer, roots of most cultivars were distributed below 20cm. The U.S. cultivars showed vertically well developed root systems as compared to others. A large amount of roots were distributed in the top 15cm of soil layer for Hatsuboshi and Koshinikari, and their root systems appeared to be shallow. In contrast, the rates of root distribution in the top 10cm of soil layer were low for Dongjin, Calrose, and Caloro. These cultivars had relatively deep root systems.

• Journal of Ginseng Research
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• v.20 no.1
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• pp.78-82
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• 1996

In order to clarify effect of transplanting angle of seedling on shape and growth of ginseng root, ginseng of seedlings were transplanted with $60^{\circ}$ and $90^{\circ}$ respectively, and the root characters of 2-, 4- and 6-year-old ginseng were investigated. The length of main root with 45$^{\circ}$was above 7 cm (standard) but that of $60^{\circ}$ and $60^{\circ}$ was below 7 cm (standard). Number of good lateral root was above 2.3 ea for $45^{\circ}$, 0~$30^{\circ}$, but below 2.3 ea per plant for 60~$90^{\circ}$ respectively. Root fresh weight with $0^{\circ}$, $30^{\circ}$, $45^{\circ}$ was heavier than that with $60^{\circ}$ and $90^{\circ}$. Root disease infection rate was highest with $0^{\circ}$. There were, no significant difference in stem length, stem diameter, leaf area, comber of palmate leaves and leaflets per plant, ratio of missing plant, root diameter in 2-, 4- and 6-year-old ginseng.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.147-154
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• 1989

The experiments were carried out to compare the growth characteristics of excised seminal roots in Japonica type, Indica- Japonica hybrids and its parents. Based on the modified culture medium by Kawata et al., several levels of pH. sucrose and casamino acid were varied in the culture media. The excised root length at 27$^{\circ}C$ incubator was little different between Japonica type and Indica-Japonica hybrids, but at 30$^{\circ}C$ incubator the excised root elongation of Indica-Japonica hybrids was much better than that of Japonica type. The dry matter weight of excised root in Indica- Japonica hybrids was significantly heavier than in Japonica type at both 27 and 30$^{\circ}C$ incubators. The difference of dry root weight between Japonica type and Indica- Japonica hybrids was caused from the number of lateral roots, especially the root numbers of 25 cm length. The main and lateral seminal root growth of Japonica type grew best at the lot of 0.2 percent casamino acid. However, the lots of 0 and 0.2 percent casamino acid showed good results in the main and lateral excised root growth. respectively of Indica-Japonica hydrids. The growth of excised roots was better in Indica-Japonica hybrids than in Japonica type at even various levels of pH, sucrose and casamino acid. Between the parents of Indica - Japonica hybrids, the excised root growth of Indica type was more predominant than that of Japonica type, and the effect of casamino acid on the excised root growth in the formar was similar to that of Indica type. This result indicated that the growth characteristics of excised seminal roots in Indica Japonica hybrids were derived from the parent, Indica type.

• Applied Biological Chemistry
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• v.11
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• pp.143-149
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• 1969

In order to investigate the inter-relation with the growth of the rice-root and its transaminase-activity, by measuring the growth of its root and transaminase-activity supplying this root with various nitrogen Compounds($NO_3$-N, $NH_4$-N and Amino acid.). The obtained results are summarized as follows; 1. Growth of rice-root supplied with $NO_3$-N is generally increased in length and weight, compared with that of the root fertilized by $NH_4$-N. 2. The above-metnioned root with $NH_4$-N is not only decreased in its weight and length but also is apt to inhibited its growth as the nitrogen concentruration is increased, in compared with the root provided with $NO_3$-N. 3. The activity of G.O.T. and G.P.T. for the root fertilized by $NH_4$-N, the badly grown root is generally increased, while of the root supplied with $NO_3$-N is decreased. 4. The activity of G.O.T. and G.P.T. for the root provided with amino acid known as the considerable growth inhibiting compound is generally decreased, while that of the badly-grown root is increased. 5. The activity of G.O.T. and G.P.T. in the supernatant fraction of the rice-root is for the most part, high and low in the mitochondrial fraction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.297-307
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• 1995

Anatomical and physiological studies of sink tissues are required for better understanding the biological plant growth system and energy metabolism Anatomy of root growth zones of two genotypes of tall fescue (Festuca arundinacea Schreb.) receiving 50 or 200 ppm N were determined, Cross-sectional anatomy and cells responses of root growth zones were observed and examined. Rapid radial root expansion occurred within the first 1.0 mm from root apex, and then increased gradually for both genotypes and N levels. Another increase in diameter occurred at high N after cell elongation slowed near 3.0 mm. Area of the central cylinder cell increased rapidly near the root apex. However, it then decreased again about 1.0 to 1.5 mm from the apex, perhaps because of pressure from the rapid increase of root diameter due largely to an increasing proportion of cortex and epidermis or hypodermis in the distal portion of the root growth zone. Root area from the apical initial to 6.0 mm distal consisted of 10 to 18% epidermis or exodermis, 67 to 79% cortex, and 10 to 22% vascular cylinder cells containing cambium cells (6 to 20%) and xylem cells (0.8 to 2.5%). These data indicate that N application affects root growth radially by increasing mainly cortex cell area, with less effect on epidermis and central cylinder cells.

• Journal of Plant Biology
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• v.18 no.4
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• pp.155-160
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• 1975

Growth responses of lettuce seeds germinated in aqueous solutions of $SO_2$ were investigated for mode of action studies of this gas. The concentration and pH of $SO_2$ solution greatly affected the growth of germinating seeds. Root growth was more sensitive to $SO_2$ than hypocotyl growth. The sensitivity of total seedling growth lay between root and hypocotyl growth. Growth inhibition of germinating seeds appeared more serioius when $SO_2$ was added during the early stage of germination.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.277-283
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• 1997

The effect of nutrient concentration and plant growth regulators on rooting of Coleus stem cuttings were investigated. In contrast to sand cutting, the nutrient solution or plant growth regulator treatment increased the root numbers and root length. The concentration of nutrient solution were 1, l/2 and 1/4 strength of the balanced nutrient solution developed by Japanese Horticultural Experimental Station and the highest root growth was obtained from 1/4 strength nutrient concentration. NAA or IBA treatment in culture solution stimulated the rooting and 0.01mg/l of NAA or IBA was effective in root development. Furthermore, days for rooting were shortened and root growth were promoted by mixing nutrient solutions with plant growth regulators and by using cutting with leaves. The rooting of Coleus was observed under microscope and the adventitious root formation initiated at 3 days after cutting with nutrient and auxin mixture.