• Korean Journal of Agricultural Science
• /
• v.14 no.1
• /
• pp.16-25
• /
• 1987

Colletotrichum acutatum, C. coccodes, C. dematium and C. gloeosporioides were detected in seed samples of red pepper (Capsicum annuum). C. dematium and C. gloeosporioides were the predominant species, maximum seed infection of the species in some samples were 84% and 28%, respectively. C. acutatum and C. coccodes were recorded only in low percentages of 1-2. The blotter method proved more suitable for detecting Colletotricum spp. than the deep freezing blotter or agar plate methods. Plating of seed components showed that C. dematium and C. gloeosporioides were recovered more frequently from seed coat, and decreasing amounts of infection were observed in the endosperm and cotyledon. Seed-borne C. dematium and C. gloeosporioides caused seed rot, damping-off, seedling blight and brown discoloration of cotyledon and hypocotyl when infected seeds were sown in agar of test tube or in soil. Inoculation experiments showed that C. acutatum was pathogenic to red fruit of red pepper and C. coccodes was highly pathogenic to red fruit and weakly pathogenic to leaf of the plant. C. dematium was highly pathogenic to leaf and green fruit and C. gloeosporioides was pathogenic to not only leaf but also green and red fruits. Host range of the four seed-borne species of Colletotrichum was also investigated.

• Journal of Ginseng Research
• /
• v.41 no.3
• /
• pp.353-360
• /
• 2017

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing root-rot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

• Molecules and Cells
• /
• v.41 no.5
• /
• pp.413-422
• /
• 2018

Soybean transgenic plants with ectopically expressed AtABF3 were produced by Agrobacterium-mediated transformation and investigated the effects of AtABF3 expression on drought and salt tolerance. Stable Agrobacterium-mediated soybean transformation was carried based on the half-seed method (Paz et al. 2006). The integration of the transgene was confirmed from the genomic DNA of transformed soybean plants using PCR and the copy number of transgene was determined by Southern blotting using leaf samples from $T_2$ seedlings. In addition to genomic integration, the expression of the transgenes was analyzed by RT-PCR and most of the transgenic lines expressed the transgenes introduced. The chosen two transgenic lines (line #2 and #9) for further experiment showed the substantial drought stress tolerance by surviving even at the end of the 20-day of drought treatment. And the positive relationship between the levels of AtABF3 gene expression and drought-tolerance was confirmed by qRT-PCR and drought tolerance test. The stronger drought tolerance of transgenic lines seemed to be resulted from physiological changes. Transgenic lines #2 and #9 showed ion leakage at a significantly lower level (P < 0.01) than ${\underline{n}}on-{\underline{t}}ransgenic$ (NT) control. In addition, the chlorophyll contents of the leaves of transgenic lines were significantly higher (P < 0.01). The results indicated that their enhanced drought tolerance was due to the prevention of cell membrane damage and maintenance of chlorophyll content. Water loss by transpiration also slowly proceeded in transgenic plants. In microscopic observation, higher stomata closure was confirmed in transgenic lines. Especially, line #9 had 56% of completely closed stomata whereas only 16% were completely open. In subsequent salt tolerance test, the apparently enhanced salt tolerance of transgenic lines was measured in ion leakage rate and chlorophyll contents. Finally, the agronomic characteristics of ectopically expressed AtABF3 transgenic plants ($T_2$) compared to NT plants under regular watering (every 4 days) or low rate of watering condition (every 10 days) was investigated. When watered regularly, the plant height of drought-tolerant line (#9) was shorter than NT plants. However, under the drought condition, total seed weight of line #9 was significantly higher than in NT plants (P < 0.01). Moreover, the pods of NT plants showed severe withering, and most of the pods failed to set normal seeds. All the evidences in the study clearly suggested that overexpression of the AtABF3 gene conferred drought and salt tolerance in major crop soybean, especially under the growth condition of low watering.

• Korean Journal of Medicinal Crop Science
• /
• v.2 no.1
• /
• pp.14-19
• /
• 1994

Elephant food(Amorphophallus konjac K.) have been utilized its tubers in workedmaterials for a health and diet food. The author supposed that it was increased the area of cultivation and demand. This experiments were conducted to select the proper covering material during winter in order to increase yield of tubers and decrease input by 2 year's continuous cultivation, also to verified ability of seed germination and to measured efficiency of photosynthesis of plant. The proper covering materials for wintering were rice straw and rice hull. These materials were covered at 5 cm thick and at field was promoted according to emergence appearing after winter. The yields were 5,790kg /10a at 4,730kg /10a, respectively. Yield increase was 120% and 80% than that of control. The seeds collected at August 22 were germinated about 84 percent, and it was not necessary to treatment of low temperature or germination-accelerated chemicals. The widest leaf area was ranged $1,218-1,438cm^2$ at October 20 and was varied. The efficiency of photosynthesis was highest at 65-95 days after leaf emergence. The line of broad leaf and high photosynthetic efficiency per unit area was greater compare with yield. Therefore, it was supposed that these characteristics will use a marker for selection for high-yielding lines.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.3
• /
• pp.521-526
• /
• 2002

A number of experimental and epidemiological studies have implicated that antiestrogenic effects of estrogen-like compounds in legumes and plant seeds are responsible for lowering breast cancer risk in human. However, few studies have been conducted to illustrate the possible chemopreventive effects of Korean traditional food materials. This study was performed to determine the cytotoxic and apoptotic effects of yellow soybeans, black soybeans and brown rice extracts on hormone-dependent and hormone-independent human breast cancer cells. Methanol-or acetone-soluble fractions of soybeans or brown rice were incubated with hormone-dependent cells (MCF-7) or hormone-independent cells (MDA-MB-231). Cell cytotoxicity was measured by MTT assay at 24, 48 and 72 hrs of incubation. Apoptotic effects of these extracts toward breast cancer cells were also determined at 48 hrs of incubation by measuring DNA fragmentation. Results indicated that the acetone-soluble fraction of brown rice exerted strongest cytotoxic effect on MCF-7 ceIls, although other fractions also reduced the number of viable MCF-7 cells after 48 hrs of incubation. Both acetone and methanol soluble fractions of all samples exerted a significant cytotoxicity towards MDA-MB-231 cells after 24 hrs of incubation, and acetone and methanol soluble fractions of brown rice were especially effective in these cells. At 48 hrs of incubation, methanol fractions of all three samples induced apopotosis of MDA-MB-231 cells. These results indicate methaol or acetone soluble fractions of yellow soybeans, black soybeans and brown rice induce cytotoxicity in both hormone-dependent and hormone-independent breast cancer cells. Therefore, possible mechanisms of cell cytotoxicity do not necessarily include antiestrogenic effects of soybean or brown rice extract. A possible anticarcinogenic effect of brown rice methanol-soluble fraction may mediated through their apoptotic effect. Further studies are requried to elucidate responsible compounds and mechanisms involved in observed anticarcinogenesis.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.36 no.2
• /
• pp.46-53
• /
• 2018

The background of this study was to consider regenerative environmental characteristics and develop foundations for conceptual grounds and applications in embodying sustainable garden designs demanded in our age. In doing so, this study aimed to have a conceptual understanding of Clement's garden theory influenced by Robinson's naturalistic distinction and compared it with Robinson's wild garden, and the results are as follows: First, for Clement, garden design included an ecological process to settle in the target site as aesthetics of space being formed by the movement of plants. In this sense, making a 'garden in motion' implies to design possibilities to adapt to nature based on trust in it and allow plant seeds not to be planned but to naturally go and find appropriate habitats. Second, the views to wildness can be separated into microscopic and macroscopic views and each has its own expressive characteristics. Robinson's gardens are small and subordinate and play mollification functions for existing spaces. On the contrary, Clement's gardens are the subject of the space, represent macroscopic strategies, and have top-down approaches embodied as infrastructure to play central roles in the ecology. Third, Robinson's and Clement's views to the operation of garden spaces acknowledge the inseparable relationship between nature's autonomy and gardens' wildness and deliver a value that the preservation of nature is a prerequisite to coexistence with the life we desire. Their gardens are analogized by interventions of environmental possibilism and ecological standpoints mediated by plants based on the perspective of environmental determinism.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.13 no.3
• /
• pp.109-114
• /
• 2011

A breeding population of Quercus glauca has been established via simple direct selection. Seedlings from naturally crossed seeds of 35 selected families growing in Jeju Island were placed using stroll repeated planting into two experimental forest located at Hannam and Sanghyo in Jeju. After 3 years of planting, characteristics of growth were examined. Growth pattern of trees in Sanghyo was better than those in Hannam. The average heights of filial were 66.8 cm in Hannam and 92.5 cm in Sanghyo. Root collar diameters of filial in Hannam and Sanghyo were 9.3 mm and 12.2 mm, respectively. A great weather differences especially in precipitation and temperature were shown between two test sites. The result of difference of growth pattern between two sites could be useful in provenance adaptability test. Data within families and individuals obtained from this study was also useful for establishment of seed orchard of Q. glauca.

• Weed & Turfgrass Science
• /
• v.5 no.3
• /
• pp.111-125
• /
• 2016

Cordgrass (Spartina spp.) is recognized as a highly invasive plant in estuaries throughout the world because of remarkable versatility and resiliency, significant reproduction, strong adaptability, rapid spreading, and vigorous growth. In this review, therefore, to provide insights on the effective management practices, the previous research works were summarized and discussed. Spartina spp. is a perennial halophyte, warm-season (C4) grass that reproduces both sexually through seeds and asexually by rhizomes. Management strategies for cordgrass have included various physical, biological, and chemical controls. Herbicides are usually the most cost-effective means of control. Currently, glyphosate, imazapyr, fluazifop and haloxyfop have been practically used. To improve the control efficacy, a combination of two more than methods (example, mowing-spraying) is needed to be applied consistently every year for at least 3 to 4 years and to be sprayed with enough dry time (>4-6 hr) at an early growth stage (before flowering). Consistently repeated application of same herbicide have to be avoided to prevent an unexpected emergence of herbicide-resistant lines. On the other hand, Spartina spp. have many positive functions for agricultural and eco-engineering purposes. Thus, we have to give more intensive research for effectively managing advantages and disadvantages of Spartina plantations.

• Horticultural Science & Technology
• /
• v.28 no.3
• /
• pp.469-475
• /
• 2010

The major deterring factor of radish consumption is bitter and pungent tastes caused by glucosinolates. Recently kohlrabi was introduced in Korea and mainly cultivated in Jeju Island during winter. Since the texture and taste of kohlrabi are similar to radish, the kohlrabi is expected to substitute radish. This study was done to compare compositional quality between kohlrabi and radish. The kohlrabi contained less reducing sugars, cellulose and pectin than the radish. The kohlrabi had harder texture than the radish. The total amino acid content in the kohlrabi was 2.7-fold higher than that in the radish. Especially hydrophilic amino acids including aspartate, glutamate and arginine, were about 3-fold higher in the kohlrabi, suggesting that the kohlrabi was more palatable than the radish. The total contents of glucosinolates in the radish in inner and outer section were higher than those in the kohlrabi by 12.4- and 28.5-fold, respectively. In a sensory test, the kohlrabi was evaluated less bitter and pungent than the radish. The kohlrabi contained more glucoraphanin, an anticancer compound, than the radish. Furthermore, the sweetness of the kohlrabi was evaluated higher than that of the radish, though kohlrabi contained less reducing sugars, probably due to high contents of hydrophilic amino acids. In conclusion, the kohlrabi was evaluated as more favorable in taste and contained more functional compounds than the radish, and thus it can be a good replacement vegetable for radish.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.23 no.3
• /
• pp.203-206
• /
• 2003

New orchardgrass(Dactylis glomerata L.) variety named as “Jangbeol 101” was developed by the National Livestock Research Institute(NLRI) in 2002. To develope the new variety of orchardgras, 5 superior clones were selected and polycrossed for seed production. Synthetic seeds were examined on the agronomic growth characteristics and forage production at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Namwon and Pyungchang from 1999 to 2002 and Jeju from 2000 to 2002, respectively. “Jangbeol 101” showed semi-erect growth habit in fall and spring and medium type in length of flag leaf and upper internode. Plant height of “Jangbeol 101” was short compared to that of standard variety, “Ambassador” and heading date was delayed about 2 days as 14th May compared to Ambassador. Characters such as winter hardiness, regrowth, moisture tolerance, disease resistance of “Jangbeol 101” were stronger or better than those of Ambassador. “Jangbeol 101” showed 9% higher dry matter yield as 12,374 kg/ha compared to Amabassador. Nutritive value was appeared to be similar in both varieties.