• Conservation Science in Museum
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• v.4
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• pp.71-78
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• 2003

The wooden striker on the Divine Bell of King Seongdeok was examined to identify the species of the wood and the outdoor wood weathering caused by solar light, moisture, temperature and air. The species of the wooden striker was identified to Zelkova serrata. When observed the striker with naked eyes, the results were surface discoloration (graying), cracking and roughness. In order to examine the morphological changes according to deterioration type, the specimen were separated to three part(I, II,III-spot). The I-spot was discolored to gray and at the same time entirely covered with dust. So the observation was impossible. The II-spot was also discolored but its texture could be observed. On it could observe numerous fungal hypae and dirts like dust flown into the cell lumens. The cell wall has been so weakened by weathering that it lost the physical intensity. This have made microchecks and splits on the cell wall. Although fungal hypae covered the cell, they did not result in wood decay. The III-spot, located just 0.5 mm below the surface, was maintaining the natural red-brown color of the wood. Its cell wall was similar to that of sound wood. These changes are different from wood decay, and limited only to the surface of the striker-less than or equal to 0.5 mm below.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.113-117
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• 1978

An attempt was made to establish a mass-screening technique for resistance to purple seed stain .disease in soybean. Seeds sterilized in 1 : 10000 'mercuric chloride for 1 minute and transffered to Petridishes containing 20ml water agar plus 50ppm of the sodium salt of 2,4-D were inoculated by placing a small agar cube containing fungal mycelium on the seed coat of each seed. A positive correlation between natural infection of purple seed :stain and purple discoloration by seed inoculation technique was highly significant and by this technique, some native soybean collections and introduced varieties were tested for resistance to the disease. Most of the soybean varieties tested were susceptible except for the varieties Hill, Harosoy and Sac, resistant comparatively.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.47-54
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• 2008

To make up original defects of the wooden materials for decks, and to supply the wooden material for outdoor, we fabricated preservative treated plywood(PTP). Copper azole (CUAZ-1) preservative was treated with a normal full-cell process. Bond Strength of PTP was not affected after the preservative treatment. The anti-fungal efficiency and dimensional stability were obtained from PTP. A little discoloration of the surface was detected, but the dimensional change or peel bonded area off were not observed after accelerated weathering test. Although some strength of PTP was reduced after 17 months of field exposure, the PTP should be applicable for outdoor applications.

• Research in Plant Disease
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• v.13 no.1
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• pp.15-19
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• 2007

A wilt disease on the greenhouse-grown chrysanthemum occurred at Kumi, Masan and Busan, Korea in $2003{\sim}2005$. Symptoms of wilting, yellowing, and marginal burning started from lower leaves and progressed upward. Early symptoms often appeared on one side, involving only one part of the plant or one side of individual leaves or stems without a vascular discoloration. Vascular tissues of the infected leaf-base's discolored to brown. Fungal isolates obtained from discolored tissues were identified as Verticillium dahliae based on its cultural and morphological characteristics. The fungus showed whitish to creamy colony pattern with abundant dark brown to black elongated microsclerotia on PDA. Conidiophores were verticillately branched and conidia were ellipsoidal to sub-cylindrical shape, and measured as $2.5{\sim}8.8{\times}2.0{\sim}3.8{\mu}m$. Pathogenicity tests by root dipping resulted in similar symptoms observed in the naturally infected chrysanthemum in fields.

• Research in Plant Disease
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• v.23 no.2
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• pp.202-205
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• 2017

Pink rot appeared in greenhouse-grown sunflower (Helianthus annuus L.) in Jeonju, Korea. The symptoms appeared as brown discoloration of sunflower head and progressed into stem in advanced stage. In order to investigate the causal organism of this disease, we isolated a fungus from the infected seeds and maintained the isolated fungal culture on potato dextrose agar medium. Conidiophores were simple or branched, 62.5 to $123.1{\mu}m$ long. Conidia were produced in basipetal chains, ellipsoidal to pyriform with oblique and prominent truncate basal scars, two-celled, hyaline and measured $10.2-21.4{\times}7.5-12.6{\mu}m$. The fungus was inoculated to a new sunflower plant and showed the typical blight on the leaves. Study of morphological characters, pathogenicity tests and sequence analysis revealed that the isolated fungus is confirmed to be Trichothecium roseum. To our knowledge, this is the first report of pink rot on sunflower caused by T. roseum in Korea.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.113-122
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• 1982

Appressorial formation of Pyricularia oryzae on leaves showed no marked difference between highly resistant Tongil and susceptible Norm No. 6. Race N-2 of the blast fungus penetrated directly into motor cells of susceptible cultivar Norm No. 6, later extensively spreading hyphae were developed, while in the cultivar Tongil, after penetration, no further hyphal extension resulted. In discoloration of infected tissues, the highly resistant cultivar Tongil not only discolored rapidly, but also the percentage of discolored cells was higher than the susceptible cultivars, Jinheung and Norm No. 6. The respiratory rate, was generally higher in infected tissue than in healthy tissue. No significant difference in the respiration rate of resistant Suwon No. 180 was not found between the infected and healthy leaf tissue, whereas, in susceptible Jinheung, a marked increase in respiratory rate was caused by blast infection. The respiratory rate increased at the appearance of the first visible symptom in all cultivars resistant or susceptible. Higher peroxidase activity was found in infected tissues as compared with healthy tissue. Peroxidase activity increased in resistant and susceptible reactions. Particularly, in resistant reaction, the increase of the activity was more pronounced. In highly resistant reaction, there was no difference in peroxidase activity between healthy and infected tissues. Ascorbic acid oxidase, hydroquinone oxidase and catechol oxidase had the same trend as the peroxidase. In contrast, activity of catalase rather decreased in leaf tissues infected with compatible races of the fungus.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.73-81
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• 2004

To develope of the inexpensive anti-stain chemicals, it was conducted to investigate the inhibitory effectiveness of mycelial growth and anti-mold effectiveness against test fungi causing surface mold of wood, iron corrosivity and hygroscopicity of six fluoride-based chemicals made from industrial by- product.Among the six chemicals. RNF-3 and RNF-4 were the most effective with respect to a mycelial growth control and anti-mold effectiveness. For the wood treatment with these chemicals, the optimum concentration was about 2% and there was no difference in the effectiveness of chemicals between wood species. The wood treated with synthesized chemicals showed a relatively high iron corrosion rate for corrosive F component whereas, in the treatment with RNF-3 and RNF-4, there was no difference from the untreated wood when the concentration was less than 2%. The hygroscopic property of wood was not effected by treatment of these chemicals. To prove the feasibility for practical using of RNF-3 and RNF-4 chemicals, it is necessary to test of anti-mold effectiveness in the sawmill by field test.