• The Korean Journal of Mycology
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• v.8 no.2
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• pp.89-94
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• 1980

Effects of seed disinfectants on loose smut (Ustilago nuda) and leaf stripe (Pyrenophora graminea) of barley were investigated in field tests. For these experiments, seed samples carrying natural infection of Ustilago nuda and Pyrenophora graminea were used and the following fungicides were used: Baytan, Baytan U, Benlate T, Busan 30, KAC-7703, P 242, Panoctine, Sisthane Ec, Sisthane Wp, Sisthane Ds, Sodium Omadine, Terracoat Zn, Vitathiram and Zinc Omadine, respectively. Results have shown that Sisthane and Benlate T have equal effect to Vitathiram against Ustil­ago nuda and Pyrenophora graminea. Baytan U was effective against loose smut but inferior to leaf stripe of barley. P 242 was effective against leaf stripe but inferior to loose smut of barley. Busan 30 have shown moderately inferior effect to Vitathiram against loose smut and leaf stripe of barley. A mild inhibition of seed germination and seedling growth of barley, naked barley and wheat seeds was observed when high concentration of Sisthane and Baytan U were treated in seedling box placed in green house conditions, but no symptom observed in field conditions.

• Fire Science and Engineering
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• v.32 no.3
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• pp.27-34
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• 2018

A Semi-Incombustible Composite Insulation Board (SICIB) that can be applied to building construction and ships was developed. The SICIBs comprised of pine leaf powder, vermiculite. The incombustibility, semi-incombustibility, and U-factor of the developed SICIBs were measured. The incombustibility of the each SICIB was determined by the proportion of combustible flexible binder and pine leaf powder. SICIB satisfied the incombustibility test without a combustible flexible binder and pine leaf powder. In addition, SICIB with 6% of pine leaf ensured its semi-incombustible performance. A combustible flexible binder or pine leaf powder over 6% failed the fire-resistant performance of SICIB. In addition, SICIBs with incombustible/semi-incombustible finishing and a 200 mm insulating layer (glass wool and sprayed poly urethane foam) met the U-factor of an external wall for buildings described in the Korean building code.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.69-81
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• 2010

The purpose of this study is to analyze the growth characteristics of native Kentucky bluegrass (Poa pratensis L.) collected in Korea. Out of Kentucky bluegrasses collected in 2000 and 2008, eight ecotypes ("Pyengchang," "Gongju," "Inje," "Donggang," "Hwasun," "Pureundle," "Cheongsong," and "Geumsan") were planted in experimental fields and pots on May 11, 2008 and May 3, 2009, respectively, for analyzing their growth characteristics. Data such as visual quality (1-9), visual density (1-9), visual color (1-9), plant height, leaf length and leaf width were analyzed. The visual quality of "Pyengchang," "Inje" and "Gongju" were enhanced compared to the rest native ecotypes of Kentucky bluegrass. "Pyengchang" showed the best visual density while "Gongju" and "Inje" showed almost evenly favorable density. However, "Pureundle," "Cheongsong," and "Geumsan" represented loose density due to the damage from the summer climate of high temperature and humidity in 2009. As for visual color, "Pyengchang" was also ranked first, maintaining high values of at least 7.6 even in the summer climate of high temperature and humidity. "Donggang" showed good color immediately after planting in the experimental field in 2008, however, undesirable color due to the damage from the summer climate of high temperature and humidity in 2009.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.419-424
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• 2015

The objective of this study was to investigate the physicochemical and antioxidant properties of a variety of commonly consumed commercial green tea. Green tea samples with the same commercial name produced at different regions were analyzed. High-grade tea samples showed higher values of lightness (L) and greenness (-a). Additionally, compared to other varieties of teas, high-grade tea samples showed higher levels of catechin, gallocatechin gallate (GCg), epicatechin gallate (ECg), theanine, and methylxanthines and a lower level of epigallocatechin (EGC). The antioxidant activity of green tea was also investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical assays. High-grade teas were observed to have higher antioxidant activities. The results of this study indicate that the catechin content, such as EGCg, GCg, and ECg levels, was found to positively influence the total antioxidant activity of green tea.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.115-120
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• 2002

Xanthomonas axonopodis pv. glycines, the causal agent of bacterial pustule of soybean, induces hypersensitive response (HR) in a non-host plant, hot pepper (Capsicum annuum). A wild-type strain (8ra) and its non-patho-genic mutant (8-13) of X. axonopodis pv. glycines were inoculated into the pepper leaf tissues and their subcellular responses to the bacterial infections were examined by electron microscopy. Intrastructural changes related to HR were found in the leaf tissues infected with 8ra from 8 h after inoculation, characterized by separation of plasmalemma from the cell wall, formation of small vacuoles and vesicles, formation of cell wall apposition, and cellular necrosis. No such responses were observed in the tissues infected with the mutant. In 8ra, the bacterial cells were attached to the cell walls, with the cell wall material dissolved into and appearing to encapsulate the bacterial cells. The bacterial cells later became entirely embedded in the cell wall material. On the other hand, in 8-13, the bacterial cells were usually not attached tightly to the plant cell wall, and no or poor encapsulation of the bacteria by the wall material occurred, although these were encircled by rather loose wall materials at the later stages.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.175-180
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• 2000

Cotyledonary somatic embryos after being cultured in a liquid MS medium for 1 week were subcultured on a solid MS medium and then the embryos germinated at a rate of 92%, but the rate was lowered by extending the culture period of the embryos on a liquid medium: 26% germination on a liquid medium culture for 4 weeks. Somatic embryos subcultured on the liquid medium showed the normal elongation of hypocotyl and radicle but in part showed secondary embryogenesis on hypocotyl and callus formation on and around the root-hypocotyl juncture. Through observation of scanning electron microscope, apical meristem in plumule showed the loose arrangement of cells, and abnormal leaf primordium formation and growth arrest of the primordium or no leaf primordium formation. Therefore, it is suggested that the germination arrest of carrot somatic embryos on liquid medium culture is due to the structural abnormality of the apical meristem in plumule.

• The Plant Pathology Journal
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• v.30 no.1
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• pp.90-95
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• 2014

This study was conducted to evaluate the resistance of 212 accessions of lettuce germplasm to gray mold disease caused by Botrytis cinerea. The lettuce germplasm were composed of five species: Lactuca sativa (193 accessions), L. sativa var. longifolia (2 accessions), L. sativa var. crispa (2 accessions), L. saligna (2 accessions), and L. serriola (1 accession); majority of these originated from Korea, Netherlands, USA, Russia, and Bulgaria. After 35 days of spray inoculation with conidial suspension ($3{\times}10^7$ conidia/ml) of B. cinerea on the surface of lettuce leaves, tested lettuce germplasm showed severe symptoms of gray mold disease. There were 208 susceptible accessions to B. cinerea counted with 100% of disease incidence and four resistant accessions, IT908801, K000598, K000599, and K021055. Two moderately resistant accessions of L. sativa, K021055 and IT908801, showed 20% of disease incidence of gray mold disease at 45 days after inoculation; and two accessions of L. saligna, K000598 and K000599, which are wild relatives of lettuce germplasm with loose-leaf type, showed complete resistance to B. cinerea. These four accessions are candidates for breeding lettuce cultivars resistant to gray mold disease.

• Applied Microscopy
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• v.38 no.1
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• pp.21-28
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• 2008

Carnivorous plants vary in their unique features of morphology, ultrastructure and biochemical properties by species. Furthermore, prey-capturing mechanism as well as structural and physiological adaptations have been used for grouping various carnivorous species. In Drosera plants, glandular trichomes, which develop in the leaf epidermis, are known to play the most important role during the prey capturing process. The present study examined such trichomes, focusing on the glandular type, in leaves of Drosera anglica using scanning and transmission electron microscopy. Three types of rudimentary glandular trichomes were found to develop within the folded leaf primordia and immature leaf during early development. The first type, stalked glandular trichomes (Type I), occurred on the margin and upper epidermis of the leaf. With maturation, the longest glandular trichomes having lengthy stalks, ca. $2.2{\sim}5.1\;mm$, developed along the margin, while shorter stalked trichomes, ca. up to $200\;{\mu}m$, were found on the inner leaf blade. The shorter ones consisted of a globose head having two layers of secretory cells, parenchyma bell cells and tracheids and a multicellular stalk. The stalks gradually decreased in length in centripetal fashion. The second type, Type II, having ca. $15{\sim}30\;{\mu}m$ short stalks, also developed along the inner blade. Both types secreted mucilage from the secretory cells which had a thin cell wall and cuticle layer. The sessile six-celled glandular trichomes were the third type, Type III, and were $25{\sim}40\;{\mu}m$ in length. They were distributed most commonly throughout the upper and lower epidermis, petiole and even on the stalk surfaces of the first two types of trichomes. The third type was also found to be involved in the active secretion. In prey capturing leaves, all trichome types secreted substances through thin cuticles in the head cell wall, which exhibited relatively loose wall components.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.130-137
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• 1983

A wide variety of pathogens are known io be seedborne, carried either as infectious mycelium internally or as contaminants on the seed coat. When seed is infected with a pathogen, the seed nay be rendered nonviable or it may remain viable but produce weak seedling. In some cases, the Infected seedling nay not be severely weakened, but nay serve as a source of primary inoculum within a community of plants. A recent problem nay be the dissemination of seedborne pathogens occurring as a result of the massive movements of seed, as a part of the 'Green revolution' Disease of great danger to agriculture may be introduced with seed from other parts of world. Seed treatment with organic mercury compounds in liquid form had become popular since about 1955. Organic mercury compounds contributed considerably to the increase in production of many crops and vegetables. In 1975, however, the use of organic mercury compound was forbidden because of doubts regarding their residual mammalian toxicity in agricultural products. Benomyl-thiram mixture, thiophanate methyl-;hiram mixture and TCMB have now been registered as seed disinfectants for the use of rice blast, brown spot and Bakanae disease. Oxathiinsthiram mixture has been registered as seed disinfectant for barley and wheat loose smut and leaf stripe of barley. Agricultural techniques have made such rapid progress that the nursery methods changed from the use of paddy nursery to box nursery designed for machine-transplanting. The spread of rice transplanting machines has caused increase of seedborne diseases. Among seedborne diseases, Bakanae disease has remarkably increased and causes much damage recently. In order to counter this trend, seed disinfectants must also be diversified. First, effective non-selective disinfectants need to be developed, and second, appropriate control methods always need to be prepared in parallel with the development of new techniques for cultivation.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.365-372
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• 2016

Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.