• Applied Microscopy
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• v.37 no.4
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• pp.281-287
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• 2007

The genus Hypoxylon is a member of the Xylariaceae that has brown to dark brown and phaseoliform single cell ascospores with a conspicuous full germ slit. Hypoxylon truncatum differs from H. annulatum, it has conspicuous perithecial mounds, dark brown stromatal surface, and absence of enriched ostiola disc. The isolate of Hypoxylon, collected from Mt. Deuk-yu in Korea, is compared with similar taxa and described. The isolation of H. truncatum is compared with similar taxa, H. annulatum, with a precise description in the SEM level in Korea.

• The Korean Journal of Mycology
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• v.25 no.3 s.82
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• pp.161-166
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• 1997

Occurrence of Hypoxylon truncatum, known as a symbiont of white jelly mushroom, was first noted and described in Korea. Two stromatal forms reported in North American collections of H. truncatum sensu Miller were also observed in Korean collections. Based on evidences from other studies, polymorphic patterns seen in six enzyme digestions of nuclear Internal Transcribed Spacer (ITS) regions of Korean isolates indicated that the two stromatal forms were genetically distinct. Because there was a clear association of stromatal morphology with genetic differences, the different stromatal forms might be different species. In addition, clear species concept on the species H. truncatum would provide aids in selecting proper strain for cultivation of white jelly mushrooms.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.10-16
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• 2000

Two wood decay ascomycetes fungi identified as Hypoxylon mammatum and H. truncatum were isolated from backyard of Korea Research Institute of Chemical Technology (KRICT) in Korea. Hypoxylon truncatum is newly recorded as a wood degrader in Korea. Unusual germination mechanisms of ascospores in H. mammatum and H. truncatum are described and illustrated. The differences between two species were noticed on the process of germ tube formation. In the process of germ tube formation, the fast movement to pigmented ascospores activated from their perispores was termed as spore eclosion that was only found in H. mammatum. This sophisticated recognition mechanism indicated the existence of specific eclosion and germ tube formation due to the composition of cell wall layers and their preferable host derive, based on examined two species under a genus. The observation on present study postulates different composition of wall layers of ascospore and different nutrient composition for germination.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.33-36
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• 2007

An attempt was made to investigate the status of harmful microorganisms occurring on different kinds of oak bed-logs during shiitake cultivation. As a result, totally 14 species of harmful microorganisms, including Trametes versicolor, were confirmed. Twelve kinds of harmful microorganisms were observed on Quercus acutissima, 9 kinds on Q. mongolica and 10 kinds on Q. aliena. Diatrype stigma, Hypoxylon truncatum, Hypoxylon sp. and Trichoderma sp. occupied 75.1% of the total harmful fungi occurred on Q. acutissima. H. truncatum and Trichoderma sp. occupied 71.2% of the total harmful fungi occurred on Q. mongolica. On Q. aliena, the occurrence of H. truncatum, Trichoderma sp. and Hypoxylon howeianum was 80.3%. D. stigma and Hypoxylon sp. were observed exclusively on Q. acutissima bed-logs, and the outbreak ratios were 51.6% and 13.1%, respectively. H. truncatum was observed on 46.6% of Q. aliena bed-logs and Trichoderma sp. was observed on 30.3% of Q. mongolica bed-logs.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.142-148
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• 1987

The results investigated of the effect of light, pH, and nutrients in vitro and the levels of fertilizer(P,K and Ca) in vivo in order to find out the effect of environmental factors in forming an appressorium of Colletotrichum truncatum were as follows; The ratio of appressorium formation promoted more in a light treatment than in a dark treatment according to investigation after three and six hours passed away. But after the period, the ratio of appressorium formation promoted highly in both treatments. Reasonable pH of appressorium formation was pH 6-pH 8. The ratio of appressorium formation was the most favorable at none nutrient level in every treatment of C-source and N-source, and suppressed in a high concentration of C-source and N-source. But according as the time passed away, the ratio of appressorium formation promoted in C-source and N-source. When their quantities were increased in P and K treatments, the ratio of appressorium formation was somewhat suppressed but it was highly suppressed in the gradual order of none fertilizer level < standard fertilizer level < doubled fertilizer level in Ca treatment according to investigation after the first three hours passed away. But after the period, the ratio of appressorium formation promoted highly regardless of the level of fertilizer.

• Applied Microscopy
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• v.29 no.3
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• pp.275-280
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• 1999

The genus of Hypoxylon, well known wood degrading fungi, is a member of the Xylariales, which has woody to carbonaceous, brown to dark brown stromata. Hypoxylon moriforme, which was isolated from heavily decayed hardwood, is fairly described by electron microscope. The isolation of H. moriforme will be the first record and the first description in Korea. The species collected, having small size of ascospores $7.5\sim9.0\times2.5\sim4.0{\mu}m$ and asci $75\sim130\times3\sim5{\mu}m$, are taxonomically compared with H. truncatum, which is well known as a popular species in Northeast Asia. And H. bovei and H. annulatum, which are the tropic to subtropic species and also compared with other temperate species of H. moriforme.

• Korean journal of applied entomology
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• v.7
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• pp.57-59
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• 1969

Effect of light on conidial formation of Colletotrichum panacicola, C. gloeosporioides, C. runcatum and C. nicotianae was examined on potato dextrose agar on which each conidial suspension was seeded. The light source was Mitsubishi day light fluorescent lamps wi th an intensity of 100-120 ft-c at the colony surface. The treatments were (i)constant light, (ii) constant darkness, and (iii) alternating light (11hr.) and darkness {13hr.) at $26\{\circ}C\pm2$. With the exception of C. nicotianae, constant light gave the greatest sporulation over that obtained in the other two treatments; there were on significant differences in number of sporulation between under constant darkness and alternating light and darkness. C. nicotianae resulted in maximum. inter mediate and minimum sporulation under alternating light and darkness. constant darkness and constant light, respectively. These differences were statistically significant at $5\%$ level. C. truncatum and C. nicotianae produced abundant conidia in the entire test; C. gloeosporioides was intermediate, and C. panacicola was the least. Differences in number of sporulation due to light. organisms. and t he interaction of these two were all statistically significant.

• The Korean Journal of Mycology
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• v.34 no.2
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• pp.88-91
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• 2006

Attempts were made to investigate the conditions of mycelia of one low-temperature type strain and one high-temperature type strain of shiitake showing poor fruit-body formation in bed-log, and to survey harmful microorganisms formed on the log surface in Gapyung County, Korea. When tested the growing ability of mycelia, the low-temperature type strain showed ca. 1.1% decrease compared with preserved original strain. And, the high-temperature type one showed ca. 8.0% decrease. The growth of isolated mycelia was tested in sawdust medium. The high-temperature type strain showed ca. 10.8% decrease compared with original strain, and the low-temperature type one showed ca. 25.1% decrease. Weight reduction rate was investigated. The high-temperature strain showed ca. 20.1% decrease and the low-temperature one ca. 19.0%. When compared with non-treatment, original high-temperature type strain showed 107.0% decrease, the isolated high-temperature type strain 49.5%, original low-temperature type one 85.4%, isolated low-temperature type one 50.0%. As the results of confrontation culture, the high-temperature type strain and the low-temperature type one were same as the original ones, respectively. And, in the bed-logs, Hypoxylon truncatum, Coriolus versicolor, Inonotus xeranticus, Daedaleopsis tricolor, Graphostroma platystoma, two species of Myxomycetes, Trichoderma sp. Hypoxylon fragiforme, H. howeianum, and Nitschkia confertula were observed as harmful microorganisms, and the bed-logs were not in good condition.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.98-106
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• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.

• Journal of Korean Society of Forest Science
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• v.86 no.2
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• pp.223-232
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• 1997

One hundred Sixty two quadrats were sampled from natural forests, in Kangwon-do and Kyungsangbuk-do. On the basis of Mueller-Dombois & Ellenberg method, field survey, which accounts for the characters of the species structure of Pinus densiflora community and Quercus mongolica community, was carried out between 1991 and 1994. To analyze the data, CCA ordination and D.B.H, analysis were used. 1. DBH analysis showed that Pinus densiflora community is likely replacing Quercus mongolica or Quercus variabilis community. DBH analysis also showed that Quercus mongolica - Lindera obtusiloba community balances among the Quercus mongolica, Fraxinus rhynchophylla, and Tilia amurensid in the canopy, and that Quercus mongolica-Abies nephrolepis community, mixed forest balances among the Quercus mongolica, Pinus koraiensis, and Abies nephrolepis in the canopy. In general, Quercus mongolica seems to remain as a dominant species. 2. A certain correlation seems to exist between nutrients types and Pinus densiflora community. Quercus mongolica prefered to grow in the medium elevation area that has medium level of total nitrogen, organic matter, and C.E.C. Pinus densiflora, Quercus serrata and Quercus variabilis were found in the low elevation area that has low level of total nitrogen, organic matter, and C.E.C. 3. There seemed to be a certain correlation between nutrients types and Quercus mongolica community. Quercus mongolica and Acer pseudosieboldianum was distributed in the slope area that has medium level of $Mg^{{+}{+}}$, $Ca^{{+}{+}}$, and C.E.C., while Abies nephrolepis, Taxus cuspidata and Pinus koraiensis in the high elevation and ridge area that has low level of $Mg^{{+}{+}}$, $Ca^{{+}{+}}$, and C.E.C. Carpinus laxiflora and Abies holophylla were found in the medium elevation area that has medium level of $Mg^{{+}{+}}$, $Ca^{{+}{+}}$, and C.E.C., while Kalopanax pious, Carpinus cordata and Acer truncatum in the moderately moist and valley area that has high level of $Mg^{{+}{+}}$, $Ca^{{+}{+}}$, and C.E.C. Pinus densiflora and Fraxinus rhynchophylla seemed to prefer the slightly dry, low elevation and ridge area.