• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.125-129
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• 2001

Eight vermiculite-based root media prepared with addition of complete fertilizer (2 g/L; N-$P_2$$O_5$-$K_2$O, 10-10-14) for potatoes (Solanum tuberosum L.) and a commercial root medium were evaluated in 2000 to develop the root media suitable for potato plug seedling production. The eight media consisted of various ratios of vermiculite, perlite, peatmoss, and compost. In addition, four rates (0, 1, 2, or 4 g/L) of the complex fertilizer for potato were added to a root medium (70% vermiculite, 10% perlite, 10% peat moss, and 10% compost by volume) to determine the optimum addition rate of the complex fertilizer for plug seedlings. Compost addition to the media increased plant height, the number of leaves per plant, and top and root fresh weight of 15-day old plug seedlings. The seedlings raised in root media containing compost produced significantly higher total tuber yield. Addition of the complex fertilizer to root media enhanced seedling growth and increased the number of tubers per plant and tuber yields. The results suggest that root media containing 50% vermiculite, 0 to 20% peat moss, 10% perlite, 20 to 40% compost, and 2 g/L complex fertilizer for potato appear suitable for potato plug seedling production.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.340-345
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• 2006

A potato (Solanum tuberosum L. cv. Superior) cultivar was grown in aeroponic cultivation system to investigate the effect of root zone cooling in summer. Based on their nutrient uptake, growth responses, and tuberization, the possibilities for potato seed production were determined. Although shoot growth and early tuberization increased in the conventional non-cooling root zone system (root zone temperature of $25\pm2^{\circ}C$), stolen growth, photosynthesis, transpiration rate and number of tubers produced were higher in the cooling root zone system ($20\pm2^{\circ}C$) than in the non-cooling system. Increasing root zone temperature above $25^{\circ}C$ stimulated absorption of K more than T-N, P, Ca, Fe and Mn. On the other hand, root zone temperatures in the range of $20^{\circ}C$ to $25^{\circ}C$ did not affect Mg contents. The lower uptake and supply to leaves of T-N, Fe and Mn at the high root zone temperature promoted early tuberization and advanced haulm senescence. The results stress the importance of keeping root zone temperature to as low as below 20, particularly in summer under temperate Bone.

• Research in Plant Disease
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• v.10 no.1
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• pp.8-12
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• 2004

The diseased ginseng plants, their trunks fall down anil roots rot, were observed in ginseng cultivation field at Bongwha, Kyungbuk. Inoculation of the bacterium isolated from root rot lesion induced a range of symptoms on leaves, trunks and roots; The bacterium caused wilting with chlorosis and black discoloration on leaves, empty of inside trunks and rot on roots. The bacterium was identified as Serritia liquefaciens based on the morphologcal and physiological characteristics. This is the first report in Korea on roots rot of ginseng occurred by S. liquefaciens.

• The Korean Journal of Ecology
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• v.22 no.2
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• pp.89-94
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• 1999

Thirty-day-old seedlings of tomato (Lycopersicon esculentum) were treated with different concentrations of HgCl$_2$(0. 10 and 50 $\mu$M) for up to 20 days. and the detailed distribution of Hg absorbed and its toxicity in different plant parts (roots, stems and leaves) were investigated. The accumulation of Hg in plants increased with external Hg concentrations. and Hg is strongly retained by roots. Further. Hg content in leaves was various. showing more accumulation in older leaves. Seedlings exposed to toxic levels of Hg showed not only the reduction of dry weight and length of both shoot and root. and chlorophyll levels in leaves but also the enhancement of malondialdehyde (a lipid peroxidation product) formation in all plant parts investigated. These results suggest that physiological impairment of a plant exposed to Hg may be achieved by internal distribution of Hg absorbed and Hg-induced oxidative stress in different plant parts.

• Plant Resources
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• v.8 no.2
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• pp.116-121
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• 2005

Compositae plants are known to contain biologically active substances that are allelopathic to agricultural crops as well as weed species. Aqueous or methanol extracts and plant residues from leaves of Xanthium occidentale were assayed against alfalfa (Medicago sativa) to determine its allelopathic effects, and the results showed that the extracts applied onto filter paper significantly inhibited seed germination as well as root growth of alfalfa. Aqueous leaf extracts of $40g\;L^{-1}$ were completely inhibitory on root growth of alfalfa, while root growths of barley (Hordeum vulgare L.) and soybean (Glycine max L.) were less sensitive. Leaf residue incorporation at $100g\;kg^{-1}$ into soil on seedling growth of barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) inhibited both shoot and root fresh weights of barnyard grass by 94 and $96\%$, respectively. Methanol extracts from BuOn and EtOAc fractions of X. occidentale reduced alfalfa root growth more than did those from hexane and water fractions. The results based on bioassay of extracts and residues show that X. occidentale had potent an allelopathic activity against other plant species.

• Mycobiology
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• v.45 no.2
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• pp.110-113
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• 2017

Severe root rot was observed in fields of cabbages (Brassica oleracea L.) in 2015 in China. Cardinal symptoms of this disease included root rot and wilting leaves. A fungus was isolated from diseased tissues consistently. Based on the morphological features and molecular analysis of the ITS-5.8S rDNA and D1/D2 domain of the 28S rRNA gene, it was identified as Plectosphaerella cucumerina. This is the first report of P. cucumerina causing cabbage root rot in China and the world.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.292-297
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• 2015

This study was carried out to have the basic and applied informations relating to develop the cultivation methods and to increase the productivity and quality of ginseng. 1 to 6 year old ginsengs of Jakyung cultivar were cultivated and the content and synthetic amount of carbohydrates were investigated with different plant tissues, growth stages, and years old. The concentration of total carbohydrates at six year old ginseng including water soluble and water insoluble carbohydrates was about 18.9%, 42.9%, and 43,6% in leaves, tap roots, and lateral roots, respectively. Water soluble carbohydrate of tap and lateral roots was slightly decreased from August until September, and then increased on November, whereas its water insoluble carbohydrate was increased from August to September and then decreased on November. Comparing with the content of carbohydrates of 1 to 6 year old ginsengs, it was continuously increased from one year old ginseng until five year old ginseng, however it was not increased much in six year old ginseng. The highest content of carbohydrates was at five year-old in all tissues of ginseng. Water soluble and water insoluble carbohydrates were significantly shown different in leaves, stems, tap roots, and lateral root at different growth stages and with different years old. The content of water soluble carbohydrate in the leaves was remarkedly higher compared to that of water insoluble carbohydrate, while in the root the content of water insoluble carbohydrate was clearly higher compared to the water soluble carbohydrate. Comparing with the synthetic amount of carbohydrates, water soluble carbohydrates was higher in the shoot than that in the root, whereas water-insoluble carbohydrates higher in the root than that in the shoot. Carbohydrates which would be utilized in ginseng tissues for short and long-term periods as major energy were appeared differently in between shoot and root, with different growth stages, and years old.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.5
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• pp.47-56
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• 2023

The Quercus variabilis and Quercus dentata, which are said to be relatively drought tolerant among the important genus Quercus that represent deciduous broad-leaved forests in Korea. These two species are widely distributed worldwide in Korea, Japan and China (northern, central, western and eastern subtropical regions). This study compared the ecological niche breadth and overlap according to growth response in 4 soil moisture gradients for the two species and tried to reveal degree of competition and ecological niche characteristics. The ecological niche breadth was 0.977±0.020 for Q. variabilis and 0.979±0.014 for Q. dentata, the latter being slightly wider. And they were similar in 5 traits (stem length, leaf lamina length, leaf width length, stem weight, leaf petiole weight), Q. variabilis was more dominant in 4 traits (leaves number, stem diameter, leaf area, leaf petiole length), and Q. dentata was more dominant in 7 traits (root length, shoot length, plant weight, root weight, shoot weight, leaf weight, leaf petiole weight). The ecological niche overlap for soil moisture between the two species overlapped most in plant structure-related traits and least in photosynthetic organ-related traits such as petiole length. As a result of principal component analysis, degree of competition between the two species for soil moisture was more severe when the soil moisture condition was low than high. Among the measured traits that affect the two-dimensional distribution, 8 traits (Leaves number, Shoot length, Stem length, Plant weight, Root weight, Shoot weight, Stem weight, Leaves weight) were correlated with the factor 1, and 2 traits (Leaf width length, Leaf petiole weight) were correlated with the factor 2 (r>0.5). These results show that the ecological response of the two species to soil moisture is not a few traits involved, but several traits are involved simultaneously.

• Journal of Plant Biotechnology
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• v.50
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• pp.137-141
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• 2023

The root of Adenophora triphylla is a highly valued medicinal resource that is used to prevent human obesity, cancer, and inflammation, whereas young leaves or sprouts of A. triphylla are used as food ingredients. In this study, we compared the antioxidant and anticancer activities of 70% ethanol extracts of A. triphylla roots and leaves. The leaf extract exhibited stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging activity, reducing power, and oxygen radical absorbance capacity (ORAC) than the root extract. Furthermore, the leaf extract was observed to be a potent source of anticancer compounds that were effective against A549 (lung cancer), LNcaP (prostate cancer), SKOV3 (ovarian cancer), and Caco-2 (colorectal cancer) cells. These results indicate that not only the roots but also the leaves of A. triphylla can serve as valuable sources of functional materials in the pharmaceutical industry.

• Korean Journal of Medicinal Crop Science
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• v.24 no.3
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• pp.198-206
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• 2016

Background: Electrical conductivity (EC) and pH are important features of nutrient solution, affecting both growth and quality of crops by altering nutrient uptake. Methods and Results: The pH values of nutrient solutions were controlled at 5.0, 5.5, 6.0, 6.5 and EC values were controlled at 0.68, 0.84, 1.23, 1.41 dS/m. Gingesng root weights were higher during the initial growth period when the plants were treated with low pH and low EC nutrient solutions. However, the higher pH and EC levels, the greater the increase in the rate of root weight between the initial and middle growth periods. The highest ginsenoside amount changed during growth period. The total ginsenoside amount was highest in the root, and the lowest in leaves at 45 and 90 days after treatment, respectively, with solution at a pH of 6.0. After 135 days of treatment, the highest total ginsenoside amount was detected in root treated with soluton with EC values of 1.23 dS/m. Conclusions: For the cultivation of ginseng using a nutriculture system, the pH and EC values of nutrient solutions should to be controlled based on the stage of growth and targeted plant organ (root or leaves).