• The Plant Pathology Journal
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• v.25 no.3
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• pp.241-246
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• 2009

Korean pine (Pinus koraiensis Sieb. et Zucc.), a five-needle pine, has recently been suffering pine wilt disease caused by non-native pinewood nematode, Bursaphelenchus xylophilus. Three-year-old Korean pine seedlings were inoculated with 10,000 pathogenic nematodes in a greenhouse to investigate disease development, water content and the density of nematodes in stems. Needle dehydration, xylem drying and pith browning started 20 days after inoculation (DAI). There were significant differences between seedlings inoculated with nematodes and control seedlings in the relative water content of stems and leaves at 20 and 30 DAI. At 60 DAI, all remaining seedlings inoculated with nematodes had died, but control seedlings all remained alive. The average number of nematodes recovered from stems of Korean pine dramatically increased from 10 to 20 DAI, and then decreased at the end of the experiment at 60 days. This study suggests that the relative water content of stems and leaves in current-year branches could be used as a useful physiological indicator for early diagnosis of pine wilt disease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s01
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• pp.4-15
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• 1989

The objective of this paper is to compare and summarize the procedure and effectiveness of some bioassay systems and to point out ways to obtain reliable results from each bioassay. Detailed C:escriptions were given for those widely-adapted bioassay methods, such as mungbean rooting (auxin), Avena first internode straight growth (auxin), dwarf rice growth (gibberellin), dwarf pea epicotyl elongation (gibberellin), radish cotyledon expansion test (cytokinin), and tobacco stem pith callus growth (cytokinin), and the effects of various plant growth regulators including some recently introduced growth retardants (Paclobutrazol, Uniconazol, etc.) were also summarized.

• Journal of the Korean Wood Science and Technology
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• v.18 no.3
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• pp.26-33
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• 1990

To study the wood quality factors of Populus nigra $\times$ maxmowiczii known a rapidly growing species, the variations of green moisture contents, bulk density, wood fibre dimensions, microfibril angles, and number of leaf knot in stem wood were investigated. The heartwood contained a higher moisture content than the corresponding sapwood. Bulk density in radial patterns variations decrease outward from the pith, then increase toward the bark. The wood-fiber length and diameters had somewhat smaller values than on Populus alba $\times$ glandulosa or Populus euramericana. The microfibril angles decreased rapidly toward the outside, and their mean values were about 16 degree. The grain angles run nearly parallel to the cell axies. Number of leaf knot showed a fluctural change above ground level to a point near the base of the crown and then increased rapidly to the top of tree and average number of leaf knot varied exclusively from tree to tree.

• Journal of the Korean Wood Science and Technology
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• v.15 no.3
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• pp.1-13
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• 1987

This study was carried out to investigate the variations of dimension and exterior shape of vessel elements, morphology of spiral thickening and ray-vessel pit in korean diffuse-porous woods (56 species, 18 families), The tangential pore diameter and vessel element length was increased, whereas the pore number per unit area($1mm^2$) was decreased from pith outwards. The tangential pore diameter was decreased but the length of vessel element was not changed from earlywood to latewood within an annual ring. However, the dimensional variations of vessel element was not able to be recognized among relative positions in peripheral variation. The exterior shape of vessel element could be classified into four types; Type 1 is without tail, Type 2 with ligulate tail, Type 3 with broad taper tail and Type 4 with the very short length between perforations. The distribution frequency of Type 2 and 3 was relatively high in comparision with the others. According to the prominence, distribution position and branched shape, the spiral thickenings could be divided into five types. The spiral thickenings occurred 52% in the species observed. Thus it was doubtful to consider the simple presence of spiral thickening as diagnostic index in diffuse-porous woods. The morphology of ray-vessel pit could be grouped as reticulate, scalariform, oval, linear and coalescent type. Most of species examined showed oval and linear type.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.42-49
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• 1988

Anatomical characteristics on abnormal type of bisected compression woods and light colored wood intervened between these dark colored compression woods on under part and their respective opposite woods on upper parts of cross section in Pinus densiflora S. et Z. stem were compared through optical microscopic investigation. and the obtained results were summarized as follows: 1. Tracheid length increased linearly as the number of rings from the pith increases in all investigated parts, but increasing tendency in tracheid length was similar within bisected two compression woods and their opposite woods. 2. Tracheids were the shortest in bisected two compression woods and tracheid length in intervened wood between these two compression woods was longer than in compression woods but shorter than in the opposite woods. 3. Bisected two compression woods and intervened wood between these two compression woods revealed similar features in tracheid transition from springwood to summerwood, intercellular space, tracheid entanglement, and cross sectional view of tracheid. but spiral check was observed only in these two compression woods, therefore the intervened wood between these two compression woods disclosed anatomical characteristics similar to, not typical of, compression woods.

• Natural Product Sciences
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• v.9 no.4
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• pp.286-290
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• 2003

Ratanjot is attributed to eight species of Boraginacae species belonging to genera Alkanna, Arnebia, Maharanga and Onosma and regarded as one of the important herbal drugs of indigenous systems of medicine. The root and root stock, which form the actual drug, are considered to be an anthelmintic, antipyretic and antiseptic. They are also claimed to be useful in burn, eczema, wounds and eruptions, and used for treating the diseases of eyes, bronchitis, abdominal pains, itch, etc. Several workers reported that the Naphthaquinones (arnebins), the main active constituents of the drug, are responsible for its colour and therapeutic efficacy. It is claimed that the Arnebia nobilis was imported to India from Afghanistan but the red coloured roots resembling with A. nobilis were found to be gathered by local people for commercial purposes during the course of botanical surey of Himalayan region. Hence, it is decided to evaluate Arnebia nobilis pharmacognostically. The important macro-microscopic features of this species are roots 1-5 cm broad; outermost xylem with broad vessels and innermost with groups of radially arranged narrow vessels while the middle region occupied by alternate rings of clusters of broad and narrow vessels and presence of pith. Besides the percentage of arnebin-1, -3 and 4 are 9.37, 10.53 and 1.72 respectively.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.43-50
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• 1999

The safety-evaluation of ancient wood structures has been executed with only visual inspection. The application of NDE(nondestructive evaluation) is required because the visual inspection has many restrictions. Among many NDE techniques, the stress wave technique was used in this research. This study focused on evaluating the extent of decay in members of ancient structures, using stress wave nondestructive technique. For application of stress wave technique to ancient structures, the threshold time which divides members into categories according to degree of decay should be determined in advance. Stress wave timer (Metriguard Model 239A) was used in this study, specimens used in this research were the members obtained from six ancient structures. All specimens were identified as Hard Pine(Pinus densiflora S. et Z. or Pinus thunbergii P.) by microscope. Each member was tested with stress wave passing radially through the pith. In this study, the stress wave time of $12{\mu}s$/cm could distinguish between sound and decayed specimens with accuracy of 77.5 percent. Also, decayed specimens could be separated into moderate and severe categories by stress wave time of $20{\mu}s$/cm. Among the three decay location groups (exterior, mixed, interior), the exterior group could be classified into sound, moderate and severe decay with the greatest accuracy. Stress wave transit time was not sensitive to small decay pockets located in interior of the member.

• Natural Product Sciences
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• v.11 no.2
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• pp.58-62
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• 2005

Pygmaeopremna herbacea (Roxb.) Mold. (Verbenaceae) is a small herb or sometimes an undershrub arising from a perennial rootstock. The dry roots are dark muddy brown in colour having root nodules. Its extensively developed roots are widely used in tribal medicine. They are used as an aphrodisiac and for the treatment of gout, rheumatism and ulcers. This study deals with the detailed pharmacognostical evaluation of the dried roots and root nodules of P. herbacea which includes macro and microscopic studies, determination of physicochemical parameters and chemoprofiling of the extract using HPTLC fingerprint profiles. It was observed that the roots consist of a well developed cortical region consisting of tangentially elongated thin walled parenchymatous cells and contain polygonal stone cells as well as compound starch grains. Also the pith was parenchymatous. The HPTLC fingerprint profile of the methanolic extract showed the presence of seven major bands. Such an analysis may thus be utilized in identifying P. herbacea and in differenciating it from other species which are similar to it or are used as its adultrants/substitutes under the same vernacular name of Bharangi.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.539-550
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• 2016

The objective of this research was to evaluate physical and mechanical properties of three species of Styrax woods from North Tapanuli in Indonesia. The woods were more than 15 years old. Physical properties such as specific gravity, green moisture content, and volume shrinkage were determined by the procedures based on BS-373 standard for small clear specimen. Furthermore, mechanical properties, including modulus of rupture, modulus of elasticity, compression parallel to grain and hardness were also tested according to the standard. Along the stem direction, the edge section had better properties compared with those near the pith section. And the base section had also better properties than upper section. Based on the specific gravity, all of the Styrax woods in this research were classified into III-IV strength classes. A good dimensional stability was demonstrated by the value of the tangential and radial ratio which reached one. With the consideration of the mechanical properties, Styrax woods were suitable use for raw materials of light construction, furniture and handy craft.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.1-6
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• 2006

Radial variations of resin canals in Pinus koraicnsis and Larix kaempferi which were cultivated-commercial trees in Korea, were examined to understand the characteristics of wood with light microscopy. Both species showed significant differences in the number of vertical resin canals along the radial direction from pith to bark. In Larix kaempferi, the diameters of horizontal resin canals and the number of epithelial cells showed a clear variation in radial direction. Namely, significant differences in the characteristics of the resin canals and epithelial cells were found in juvenile and adult woods. Consequently, it was concluded that the characteristics of resin canals can he used to estimate the wood quality.