• Title/Summary/Keyword: U forest

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Spore Inoculum Effectiveness of Korean and American Strains of Ectomycorrhizal Fungus Pisolithus tinctorius under Nursery Conditions (한국산(韓國産)과 미국산(美國産) 모래밭버섯 균근균(菌根菌)의 리기테다 소나무 파종균(播種苗)에 대한 포자접종효과(胞子接種効果) 비교(比較))

  • Lee, Kyung Joon;Koo, Chang Duck
    • Journal of Korean Society of Forest Science
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    • v.65 no.1
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    • pp.43-47
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    • 1984
  • Pinus rigida ${\times}$ P. taeda seedlings in a nursery was inoculated with basidiospores of Pisolithus tinctorius (Pt) either collected from Suweon, Korea or introduced from U.S.A. to compare the effectiveness of the spores from two different origins as mycorrhizal inocula. Nursery beds were fumigated with methyl bromide and 1g of spores was used to inoculate $1m^2$ of soil surface just before seed sowing. Seedlings inoculated with American Pt (#250 strain from Georgia, U.S.A.) were 15% taller than Korean Pt at the end of the first growing season. The seedlings from fumigation treatment only (no inoculation involved) was slightly taller (statistically unsignificant) than those with Korean Pt, but slightly smaller than those with American Pt. In a subsequent year experiment, the seedlings inoculated with American and Korean Pt after soil fumigation were 66% and 60% taller, respectively, than seedlings infected by natural fungi without soil fumigation, suggesting the dual effects of Pt and fumigation on the seedling growth. Therefore potential of Pt spores for an effective inoculum exists and selection of Pt strains which have adapted to specific local environments is needed to develop better sources of mycorrhizal inocula.

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Occurrence of Powdery Mildew Caused by Erysiphe abeliicola on Glossy Abelia in Korea (Erysiphe abeliicola에 의한 꽃댕강나무 흰가루병 발생)

  • Cho, Sung-Eun;Park, Ji-Hyun;Lee, Seung-Kyu;Lee, Sang-Hyun;Shin, Hyeon-Dong
    • Research in Plant Disease
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    • v.18 no.2
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    • pp.133-138
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    • 2012
  • In November 2009, a powdery mildew on glossy abelia (Abelia ${\times}$ grandiflora) was found in Seogwipo, Jeju Island, Korea. Further survey in the southern part of Korea, e.g., Jeju, Busan, and Tongyeong confirmed occurrence of the disease. White colonies were present on leaves, young stems, and flowers, detracting from their beauty in landscape plantings. Severely infected lesions were discolored to red-purplish. Based on the morphological characteristics and analysis of rDNA, the fungus associated with the symptoms was identified as Erysiphe abeliicola U. Braun & S. Takam. This work provides the morphological feature of its anamorph for the first time, which is characterized by having multi-lobed hyphal appressoria and short foot-cells of conidiophores. Morphological characteristics of mature chasmothecia were consistent with the previous Japanese record of this species. The sequence of internal transcribed spacer region of ribosomal DNA obtained from a Korean sample showed that this species places in the section Microsphaera of the genus Erysiphe in phylogenetic position, corresponding with the classical taxonomy. This is the first report of E. abeliicola and its host plant in Korea. The host plant A. ${\times}$ grandiflora is newly listed in the host range of E. abeliicola.

Comparison of Lignocellulose degradation properties of Lentinula edodes varieties (표고(Lentinula edodes) 품종별 목질계 섬유소 분해효소 특성 비교)

  • Jeong, Sang-Wook;Jang, Eun-Kyoung;Choi, Seul-Ki;Seo, Kyoung-Sun;Jeong, Hee-Gyeong;Lee, Won-Ho;Ban, Seung-Eon
    • Journal of Mushroom
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    • v.20 no.1
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    • pp.29-33
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    • 2022
  • In this study, five different Lentinula edodes cultivar (Chamaram, Sanbaekhyang, Sanjo 713ho, Sanjo 715ho, Sanjo 718ho) were evaluated for their ability to decolorize Remazol Brilliant Blue R (RBBR) in MEB medium, respectively. Chamaram and Sanjo 713ho decolorized RBBR rapidly in MEB medium within 3 and 5 days. The activities of manganese peroxidase (MnP) and laccase were determined on the MEB medium with and without lignin. Sanjo 713ho resulted the highest ligninolytic enzyme activities on incubation day 1, indicating of 1,213 U/mg of MnP activity and 1,421 U/mg of laccase activity.

Pproblems in the design of grass waterway (초생수로설계상의 유의점)

  • 서연용
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.8 no.1
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    • pp.1071-1076
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    • 1966
  • In this country grassed waterway practice has long been employed for the protection of drainage or diversion ditches in treating the sloped forest lands. However, the hydraulic characteristics of flow in the ditches have been entirely away from consideration in determining the dimensions of the ditches. This paper is intended first to bring forth some problems which should be brought ioto Consideration in designing grassed waterway including hydrologic aspect for determining the drainage requirement, erosion resistance of various grasses and other factors related to the hydraulics of ditch and second to introduce to readers a method of grassed waterway design, though modified, proposed for U. S. Soil Conservation Service practice. The method presented in the paper was primarily based upon the data originated from the experiments of U. S. Soil Conservation Service laboratories and further investigations on the factors involved are hoped to be conducted for applying the design criteria in this country. It is recommended to use the method of grassed waterway design ,presented in this paper from the view point of wide employment of grass lining on ditches which is obtainable at the lower cost and in abundance every where in this country.

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Livelihood sustainability of small-scale fishing households: an empirical analysis of U Minh wetland, Ca Mau province, Vietnam

  • Nguyen Thi Kim Quyen;Dang Thi Phuong;Vu Dang Ha Quyen
    • Fisheries and Aquatic Sciences
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    • v.27 no.9
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    • pp.552-564
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    • 2024
  • This paper used the UK Agency for International Development sustainable livelihood framework to measure small-scale in-land fishing household's livelihood by sustainable livelihood capital index in the vulnerable context of aquatic natural resource depletion in the wetland forest of Ca Mau province, Vietnam. Findings indicated that fishing households' livelihood capital is unsustainable and inadequate. The result took note of the beneficial physical capital while underlining the human, natural, financial, and social capital's limitations in achieving livelihood sustainability. The limitations were found to be a low score of composite index of sustainable livelihood capital (less than an average score of 0.5) whereas the outstanding score of physical capital was found. Providing training in the adoption of new livelihood models, learning livelihood diversification, access to formal credit, and appropriate coverage of social safety-net programs might help mitigate the unsustainable livelihood of inland fishing households.

Curing Behavior and Adhesion Performance of Urea-Melamine-Formaldehyde (UMF) Resin by Staged Addition of Melamine (멜라민 첨가 순서에 따른 UMF 접착제의 경화거동과 접착력의 영향)

  • Xu, Guang-Zhu;Eom, Young-Geun;Lee, Young-Kyu;Lim, Dong-Hyuk;Lee, Byoung-Ho;Kim, Hyun-Joong
    • Journal of Adhesion and Interface
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    • v.10 no.2
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    • pp.84-89
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    • 2009
  • The objective of this research was to investigate the curing behavior and adhesion performance of urea-melamine-formaldehyde (UMF) resin for the four types of UMF-1, UMF-2, UMF-3, and UMF-4 which synthesized by the staged addition of melamine. Also, various network structures of these resin types were discussed based on their different curing behavior and adhesion performance. The curing behavior was evaluated by DMTA and thermal stability was checked by TGA. Adhesion performance was evaluated by dry and wet shear strengths and the pH value of each cured resin was checked to see its effect on the adhesion performance. The results indicated that the UMF-1 resin type by the addition of melamine initially with the urea and formaldehyde at the same F/(U+M) rate showed the lowest thermal stability, rigidity (${\Delta}E^{\prime}$), temperature of tan ${\delta}$ maximum ($T_{tan}\;_{\delta}$), and wet shear strength, and pH value of cured resin. In wet shear strength, however, the UMF-4 resin type appears to be slightly higher than UMF-1 resin type.

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Redrying Fire - Retardant - Treated Structural Plywood (구조용(構造用) 내화처리(耐火處理) 합판(合板)의 재건조(再乾燥)에 관(關)한 연구(硏究))

  • Lee, Phil-Woo;Schaffer, E.L.
    • Journal of the Korean Wood Science and Technology
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    • v.9 no.4
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    • pp.1-21
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    • 1981
  • Exterior grades of Douglas-fir and aspen plywood were impregnated with interior fire-retardant chemicals and redried under low-, intermediate-, and high-temperature drying conditions. Fire-retardant treatments included borax-boric acid, chromated zinc chloride, minalith, pyresote, and a commercial formulation. Drying processes included kiln and press-drying. Evaluated were drying rates and defects generated. The borax-boric acid and the commercial treatments redried at rates similar to water-treated controls. Other salt treatments were significantly slower drying and more defect prone. Chromated zinc chloride treatment was consistently the slowest drying and most defect prone. Press drying was three times faster at an equivalent temperature level. However, thickness shrinkage doubled because of 50 1b/in. platen pressure.

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