• Journal of Forest and Environmental Science
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• v.30 no.3
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• pp.277-284
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• 2014

Status of Arbuscular Mycorrhizal (AM) colonization in seven tree species (Albizia saman, Acacia auriculiformis A. Cunn. ex Benth., Albizia lebbeck, Chickrassia tabularis A. Juss., Eucalyptus camaldulensis Dehnn., Gmelina arborea (Roxb) DC, Swietenia macrophylla King.) collected from the hilly areas of Chittagong University (CU) was investigated. Roots and rhizosphere soil samples were collected in different seasons (pre-monsoon, monsoon and post monsoon). Percentage of AM colonization in root and number of spores/100 gm dry soil were assessed. The result of the investigation reveals that the intensity and percentage of AM colonization varied in different forest tree species in different seasons. In this study, maximum AM colonization and spore population were found in pre-monsoon and minimum were in monsoon season. The intensity of colonization was maximum in C. tabularis (74.43%) in pre-monsoon, A. lebbeck (69.45%) in monsoon and S. macrophylla (67.8%) in post monsoon seasons and minimum in A. auriculiformis (53.75%) during pre-monsoon, A. saman (24.4%) in monsoon and A. saman (19.36%) in post monsoon. The number of spores found per 100 g dry soil ranged between 164-376 during pre-monsoon, 27-310 during monsoon and 194-299 in post monsoon season. Out of six recognized genera of AM fungi, Glomus, Sclerocystis, Entrophospora, Scutellospora, Acaulospora and other unidentified spores were observed.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.166-177
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• 1995

This study was carried out to discuss how soils in the area planned for a forest road construction can be mechanically tested and practically applied. For this, 16 soil test samples from 8 plots(2 samples per plot) were used. The major tests are focused on unit weight before and after cut, water content, liquid and plastic limits, sieve and hydrometer analysis etc. The total unit weight(${\rho}_t$) before and after cut are $1.69g/cm^3$ and $1.19g/cm^3$, respectively. Their water contents are 21.0% and 20.5%. The coefficient of uniformity U and coefficient of curvature C obtained from sieve and hydrometer analysis are 125 and 0.42, which mean generally not well graded. On the soil classification by USCS, SM(silty sand or silt-sand mixed soil)is a Key soil, but it seems to be not good for fill material. From the standard proctor test are resulted $1.40{\pm}0.065g/cm^3$ for the unit weight(${\rho}$) in the nature and $1.88{\pm}0.049g/cm^3$ for the optimum proctor unit weight(${\rho}pr$) each. With this to say, it is necessary more powerful compaction work at earth filling, with which this soil reachs enough the ${\rho}pr$, and more earth.

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.43-50
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• 2014

The purpose of study was to analyze secreted nectar volume, nectar sugar content and amino acid in addition to estimating honey quantities that can ultimately reap in male and female flowers of Evodia daniellii Hemsl.. The maximum blooming period of male flowers was on 24 to 26 July in 2012. On average, nectar volume secreted by nectary was $2.73{\pm}0.73{\mu}L$ from one male flower and nectar concentration showed 17.4%. The maximum blooming period of female flowers was on 7 to 9 August in 2012. Nectar volume secreted by nectary was $0.63{\pm}0.49{\mu}L$ from one female flower and nectar concentration showed 25.7%, averagely. As results of correlation analysis between the meteorological factors and nectar characteristics, we found that nectar quantities and concentration were influenced by temperature and relative humidity. Sugar content was calculated at $48.0{\pm}5.2{\mu}g$ per a male flower and $37.8{\pm}8.7{\mu}g$ per a female flower, which meant that both values were not significantly different (Mann-Whitney's U-test, p=0.400). The minimum estimates of honey harvest for a male and female inflorescence were 67.8 g and 53.5 g, respectively. Analysis of amino acid showed that Serine, Glycine and Alanine were more abundant in male flowers, however Asparatate, Glutamate, Asparagine and Glutamine were more abundant in female flowers.

• Mycobiology
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• v.42 no.1
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• pp.34-40
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• 2014

Usnea longissima has a long history of use as a traditional medicine. Several bioactive compounds, primarily belonging to the polyketide family, have been isolated from U. longissima. However, the genes for the biosynthesis of these compounds are yet to be identified. In the present study, three different types of non-reducing polyketide synthases (UlPKS2, UlPKS4, and UlPKS6) were identified from a cultured lichen-forming fungus of U. longissima. Phylogenetic analysis of product template domains showed that UlPKS2 and UlPKS4 belong to group IV, which includes the non-reducing polyketide synthases with an methyltransferase (MeT) domain that are involved in methylorcinol-based compound synthesis; UlPKS6 was found to belong to group I, which includes the non-reducing polyketide synthases that synthesize single aromatic ring polyketides, such as orsellinic acid. Reverse transcriptase-PCR analysis demonstrated that UlPKS2 and UlPKS4 were upregulated by sucrose; UlPKS6 was downregulated by asparagine, glycine, and alanine.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.2
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• pp.46-46
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• 1991

Adequate regrowth control of weeds and shrubs has been one of the important problem for pasture establishment by overseeding on reclaimed forest hilly land. This experiment was carried out on sloping shrub land near Anseong, Gyeonggido to evaluate the effects of herbicide application on growth control of native weeds, shrubs and trees. We evaluated 63 different weeds and wood species in the trials, which are grown common in korean forest. Buthidazol and 4 other herbicides (sodium chlorate, glyphosate, U-46 and gramoxone) were sprayed each at two application rates during the period of the most intensive growth, on 20 July 45 days before overseeding of pasture species. Glyphosate and sodium chlorate gave excellant control of growth of all species. However. Uncus effusus, Carex heterostachya, Polygonatum humile, Rubus corchorifolius, Lonicera coeralea and Rhododendron mucronulatum were classified as a tolerant weed and wood species to herbicides. Herbicide buthidazol showed also successive control of regrowth of weeds and wood species. But buthidazol was evaluated as a none available herbicide for use in pasture establishment. because o! their long persist of toxic herbicide residue in soils after treatments. Herbicide U-46 and gramoxone had almost no effect on regrowth of shrubs and tree species

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.158-163
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• 1999

Powdery mildew diseases previously unrecorded in Korea were noticed on four species of ornamental trees. Field observations on each disease were described and the causal fungi were identified. Powdery mildew of Symplocos chinensis for. pilosa was found to occur mildly, especially on plants growing in shade. The causal fungus was identified as Microsphaera nomurae U. Braun. Cornus florida was found to be infected with Microsphaera pulchra Cooke & Peck and supposed to be epidemic in nursery. Powdery mildew of Malus baccata occurred on young leaves and herbaceous stems in nursery. The causal fungus was classified as Podosphaera leucotricha (Ellis & Everh.) Salmon. Powdery mildew of Ulmus macrocarpa was found to occur in autumn and severe on young shoots. Uncinula kenjiana Homma was identified as the causal fungus.

• Korean journal of applied entomology
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• v.28 no.1
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• pp.1-3
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• 1989

Parasitylenchus orthotomici sp. n. is described as a nematode parasite of Orthotomicus an¬gulatus in Korea. In a sample of 170 beetles randomly collected from Pinus densiflora S. et. Z, 51. 8% were parasitized by nematodes. The number of nematodes per bark beetle was ranged from 1 to 97. The parasitisms of F, generation were ranged from 43.2% to 52%. There was no positive tendency in nematode parasitism between sun-side and shade-side.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.127-132
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• 2019

This study aimed to investigate the differences in habitat environment and characteristics of small rodent populations with time elapse after thinning in Japanese larch (Larix kaempferi) plantations, Mt. Janggun, Gyeongbuk Province, South Korea. We found that there were significant differences in habitat environment, number of tree, shrub stems, coverage of overstory, midstory, rock and number of coarse woody debris (CWD) between thinned and unthinned forest stands. We captured four small rodent species. Total number of captured small rodent were higher in thinned stands. Male-to-female ratio of Apodemus agrarius, and A. peninsulae were both the highest in forest stand 3 year after thinning. The differences in number of captured and sex ratio of small rodents might be related to habitat environment between thinned and unthinned stands. Thus, thinning can provide good habitat for small rodents by developing understory vegetation and increasing CWD in Japanese larch plantations. These results suggest that forest management through maintenance of CWD and induction of midstory and understory vegetation after thinning is necessary to maintain small rodents diversity.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.133-137
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• 2019

This study was conducted to clarify the morphological characteristics of Siberian flying squirrel (Pteromys volans). We investigated 6 morphological characteristics from April, 2014 to March 2016 at Mt. Baekwoon, Wonju, Gangwon province. We found that Siberian flying squirrel showed female-biased sexual dimorphism. This result would be related to reproductive strategy of the species which female nurse offspring alone. As results of comparison of morphological characteristics from Korea, Finland and Japan, both body weight and head-body length appeared heavier and longer from high-latitude to low-latitude. This result suggest that morphological difference between different latitudes would be related with climate and habitat environment. The more researches would be needed with other morphological characteristics of Siberian flying squirrel.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.295-301
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• 1992

Eight crop residues : 1, sorghum (Sorqhum bicolor) straw, 2, maize (Zea mays) straw, 3, cotton (Gossypium Sp.) straw, 4, sunflower (Helianthus Sp.) straw, 5, cotton (Gossypium Sp.) seed hulls, 6, groundnut (Archais hypogaea) hulls, 7, maize (Zea mays) cobs, 8, sugarcane (Saccharum officinarum) bagasse and two forest grasses 9, Heteropogan contortus dry grass and 10, Sehima nervosum dry grass were subjected to three physical processing 1, chopping (2-3 cm) 2, grinding (8 mm sieve) and 3, pelleting (10 mm die holes). The processed material was fed ad lib. Along with 250 g of concentrate mixture per head per day to 6 adult local goats and 16 adult Nellore rams in ten digestion experiments and finally assessed the nutritive value of the processed roughages by difference method. Grinding increased bulk density by 32.4 (cotton seed hulls, CSH) to 88.1% (Sehima dry grass) while pelleting of ground material increased bulk density by 53.9 (maize cobs) to 235.8% (maize straw). The average particle size ranged from $584.1/^U$ (sorghum straw) to $1467/^U$ (CSH). Modulus of uniformity ranged from 2:5:3 (sorghum straw) to 7:2:1 (CSH) while modulus of fineness ranged from 3.4 (sorghum straw) to 5.4 (CSH). Molasses absorbability was highest with cotton seed hulls and least with maize cobs. Pelleting increased DM intake of the residues except cotton seed hulls compared to grinding. Grinding of chopped material/unprocessed material increased DM intake on sorghum straw and cotton seed hulls. Sheep consumed more DM compared to goats on all the residues except sorghum and sunflower straws. Pelleting increased nutritive value of all the residues compared to grinding and chopping. However, no difference was observed in the nutritive value due to grinding and chopping. Goats performed better compared to sheep in utilizing the fibrous residues.