• 한국균학회지
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• 제47권3호
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• pp.209-218
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• 2019

During a survey of fungal diversity in Korea, two fungal strains, KNU17-1 and KNU17-199, were isolated from paddy field soil in Yangpyeong and Sancheong, respectively, in Korea. These fungal isolates were analyzed based on their morphological characteristics and the molecular phylogenetic analysis of the internal transcribed spacer (ITS) rDNA sequences. On the basis of their morphology and phylogeny, KNU17-1 and KNU17-199 isolates were identified as Albifimbria verrucaria and Deconica coprophila, respectively. To the best of our knowledge, A. verrucaria and D. coprophila have not yet been reported in Korea. Thus, this is the first report of these species in Korea.

• 지질공학
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• 제29권4호
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• pp.383-391
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• 2019

Bio-grouting based on microbial-induced calcite precipitation (MICP) is recently emerging as a novel and environmentally friendly technique for improvement of coarse-grained ground. To date, the mechanical behaviour of bio-grouted coarse-grained soil with different calcite contents and grain sizes still remains poorly understood. The primary objective of this study is to investigate the influence of calcite content on the mechanical properties of bio-grouted coarse-grained soil with different grain sizes. This is achieved through an integrated study of uniaxial loading experiments of bio-grouted coarse-grained soil, 3D digitization of the grains in conjunction with discrete element modelling (DEM). In the DEM model, aggregates were represented by clump logic based on the 3D morphology digitization of the typical coarse-grained aggregates while the CaCO₃ was represented by small-sized bonded particle model. The computed stress-strain relations and failure patterns of the bio-grouted coarse-grained soil were validated against the measured results. Both experimental and numerical investigation suggest that aggregate sizes and calcite content significantly influence the mechanical behaviour of bio-cemented aggregates. The strength of the bio-grouted coarse-grained soil increases linearly with calcite content, but decreases non-linearly with the increasing particle size for all calcite contents. The experimental-based DEM approach developed in this study also offers an optional avenue for the exploring of micro-mechanisms contributing to the mechanical response of bio-grouted coarse-grained soils.

• Mycobiology
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• 제51권2호
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• pp.72-78
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• 2023

In this study, a fungal strain KNUF-22-025 belonging to the genus Botryotrichum was isolated from the soil in Korea. The cultural and morphological characteristics of this strain differed from those of closely related species. On malt extract agar, strain KNUF-22-025 showed slower growth than most of the related species, except B. domesticum. The conidia size (9.6-21.1×9.9-18.4 ㎛) of strain KNUF-22-025 was larger than those of B. piluliferum, B. domesticum, and B. peruvianum but smaller than those of B. atrogriseum and B. iranicum. Conidiophores in strain KNUF-22-025 (137 ㎛) were longer than those in other closely related species but shorter than those in B. atrogriseum. Multi-locus analysis of molecular markers, such as ITS, 28S ribosomal DNA, RBP2, and TUB2 revealed that strain KNUF-22-025 was distinct from other Botryotrichum species. Thus, this strain is proposed as a novel species based on morphological characteristics along with molecular phylogeny and named Botryotrichum luteum sp. nov.

• 한국균학회지
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• 제51권2호
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• pp.101-109
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• 2023

A fungal strain designated KNUF-21-66Q1 was isolated from soil in Chungcheongbuk Province, Korea. Moderate growth of colonies was observed on potato dextrose agar, oatmeal agar (OA), malt extract agar, and cornmeal agar media at 25℃, and the detailed morphology was examined on OA medium. The colonies on OA medium were flat, had entire margin, hyaline, and yellow concentric rings in 3-4 weeks. Conidiomata were pycnidial, solitary or clustered, globose to subglobose, black-brown, and 300-500 ㎛ in diameter. Conidiogenous cells were smooth, hyaline, globose to ampulliform, and 6.0-9.0×3.0-6.0 ㎛ in size (n=15). Conidia were hyaline to pale brown, slightly golden, obovoid to slightly ellipsoidal, smooth, guttulate, and 3.0-4.7×2.1-3.3 ㎛ in size (n=100). The strain was confirmed based on phylogenetic analysis using internal transcribed spacer regions, the partial 28S rDNA of large subunit, and β-tubulin gene sequences. The morphological observations and phylogenetic analysis revealed that the strain KNUF-21-66Q1 was similar to the previously described Paraconiothyrium kelleni. To our knowledge, this is the first report of P. kelleni in Korea.

• 환경생물
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• 제28권3호
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• pp.150-157
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• 2010

자연 토양 및 Burkholderia cepacia를 접종한 멸균 토양에 PBSA film을 매립하여 PBSA의 생분해 특성을 조사하였다. 상온에서 80일간 매립 시험을 실시한 결과, 자연 토양에서는 PBSA film의 34.0%, B. cepacia를 접종한 멸균 토양에서는 59.2%의 질량 감소가 일어났으며 PBSA film의 표면 형태 변화도 B. cepacia를 접종한 멸균 토양에 매립한 경우가 자연 토양에 매립한 경우에 비하여 PBSA film 표면의 침식 및 균열이 더 빠르게 일어났다. PBSA film을 매립하였을 때 80일 후 자연 토양에서 세균수는 6~7배 증가한 반면 B. cepacia를 접종한 멸균 토양에서 개체수는 10~14배 증가하였다.

• 한국토양비료학회지
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• 제37권5호
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• pp.336-340
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• 2004

고추 주산단지인 충북 제천, 괴산, 경북 의성, 안동 전남 고창 및 강원 평창 등 6개 지역 119 농가포장을 중심으로 실시한 세부정밀토양조사 결과에 의해 밝혀진 토성, 배수 등급, 경사, 석력함량, 유효토심 등의 토양특성과 고추 수량을 비교하여 고추 재배지의 적지기준을 설정하였다. 고추재배지의 토양물리성과 고추수량을 비교하여보면 사양질의 토성, 양호한 배수, 7-15%의 경사, 석력함량 10-20%, 유효토심 100 cm 이상, 경반층 깊이가 100 cm 이상이며 암반노출이 없는 토양에서 수량이 가장 높았다. 고추의 역병 발병율은 점토함량이 많고, 배수가 불량하고. 포장의 경사가 완만하며 석력함량이 적을수록 높아지는 경향이었다. 충북 진천군에 고추 재배적지 기준을 적용한 결과 최적지 22.5,% 적지 21.3%, 가능지 16.0%, 저위생산지 40.2%로 나타났으며 타 지역도 적용할 수 있는 지리정보기반을 구축하였다.

• 한국토양비료학회지
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• 제23권1호
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• pp.60-66
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• 1990

영남지역(嶺南地域)의 수종(數種) 토양통(土壤統)에서 경작여부(耕作與否)에 따른 토착(土着) 대두근류균(大豆根瘤菌)의 분포특성(分布特性)을 구명(究明)하였다. 이를 위하여, 토양통(土壤統)이 서로 다른 5개(個) 지점(地點)의 경작지(耕作地)와 미경작지(未耕作地) 토양(土壤)의 대두(大豆) 접종효과(接種效果)(Soil inoculum potential)와 토착근류균(土着根瘤菌)의 취락형태적(聚落形態的) 분포특성(分布特性)을 조사(調査)하였는데 그 결과(結果)는 다음과 같았다. 1. 영남지역(嶺南地域)에 분포(分布)한 토착(土着) 대두근류균(大豆根瘤菌)의 밀도(密度)는 경작지(耕作地)의 경우 $10^4Cells/g$. soil 이상(以上)이었으나 미경작지(未耕作地)에서는 경미(輕微)하였다. 2. 경작지(耕作地) 토양(土壤)의 대두(大豆) 접종효과(接種效果)(Soil inoculum potential)는 NifTAL의 우수근류근(優秀根瘤菌) 접종제(接種劑) TAL 보다 좋았고, 대두근류균(大豆根瘤菌)의 질소고정(窒素固定) 특성면(特性面)에서 근류(根瘤) 무게가 근류수(根瘤數)를 보상(報償)하였다. 3. 토착(土着) 대두근류균(大豆根瘤菌)의 취락형태별(聚落形態別) 분포(分布)는 경작여부(耕作與否)에 따라 상이(相異)하였는데, "Dry"형(形) 기경지(旣耕地)에서, "Wet"형(形)은 미경작지(未耕作地)에서 각각(各各) 우점경향(優占傾向)을 보였다. 4. 토착(土着) 대두근류균(大豆根瘤菌)의 취락형태별(聚落形態別) 공생효과(共生效果)는 "Dry"형(形)이 "Wet"형(形)보다 좋았다. 따라서 숙전(熟田)에서의 대두생육(大豆生育)은 "Dry"형(形) 토착(土着) 대두근류균(大豆根瘤菌)의 밀도(密度)에 크게 영향(影響)을 받을 것으로 판단(判斷)되었다.

• Mycobiology
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• 제49권4호
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• pp.346-354
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• 2021

The genus Aspergillus is commonly isolated from various marine and terrestrial environments; however, only a few species have been studied in rhizosphere soil. As part of the Korean indigenous fungal excavation project, we investigated fungal diversity from rhizosphere soil, focusing on Aspergillus species. A total of 13 strains were isolated from the rhizosphere soil of three different plants. Based on phylogenetic analysis of β-tubulin and calmodulin and morphological characteristics, we identified five Aspergillus species. A. calidoustus and A. pseudodeflectus were commonly isolated from the rhizosphere soil. Four species were confirmed as unrecorded species in Korea: A. calidoustus, A. dimorphicus, A. germanicus, and A. pseudodeflecuts. The detailed morphological descriptions of these unrecorded species are provided.

• 농업과학연구
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• 제37권3호
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• pp.413-433
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• 2010

South Dakota is an important agricultural state in the United States with annual cash receipts from agricultural products exceeding $9 billion dollars. This production is possible because of large areas of productive soils. This publication describes the general characteristics and qualities of the major soil groups recognized in South Dakota. The soil forming factors are briefly described, soil classification is introduced, and the genesis of typical Udalf and Ustoll soils are discussed. Soil management issues impacting the use of SD soils are considered. Long-term (>70 yrs) cultivation has significantly reduced surface soil organic carbon levels (>30% reduction) when compared to non-cultivated soil. Soil test phosphorus levels significantly increased in cultivated fields due to commercial P fertilization. The major long-term production problems for SD soils are conservation of soil moisture, organic matter and nitrogen losses, fertility management, and wind and water erosion control.

• 한국토양동물학회지
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• 제11권1_2호
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• pp.13-15
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• 2006

This report concerns with three species of eriophyid mites on Licium chinensis in Korea. Of them, the external morphology of Aceria tjyingi (Manson 1973) was observed with Scanning Electron Microscope. The author reviewed three species of Korean eryophid mites and suggests Korean names of Aceria kuko kishida, A. macrodonis Keifer, and A. tjyngi (Manson), respectively.