• 한국토양비료학회지
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• 제24권1호
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• pp.61-68
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• 1991

영남지역(嶺南地域) 3개(個) 토양(土壤)에서 근류균(根瘤菌) Bradyrhizobiurn japonicurn 30균류(菌類)를 분리(分離)하여, 우리나라 장백(長白)콩과 미국(美國)의 Clark 대두품종(大豆品種)에 대한 이들의 접종효과와 각 토양별(土壤別) 혈청학적(血淸學的) 분포특성(分布特性)을 조사(調査)한 결과(結果)는 다음과 같았다. 1. 토착근류균(土着根瘤根)의 대두(大豆) 품종별(品種別) 근류무게의 경우 장백(長白)콩에서, 식물체(植物體) 건물중(乾物重) 질소함량(窒素含量) Clarck에서 각각(各各) 높았는데, 토양별(土壤別)로는 1번(밀양군(密陽君) 상남면(上南面))>2번(창원군(昌原郡) 동면(東面))>3번 토양(土壤) (창원군(昌原郡) 진북면(鎭北面)) 균주(菌株) 순(順)이었다. 2. 토착근류균(土着根瘤根) 중 식물체(植物體) 질소함량(窒素含量)에 있어서 가장 좋은 접종효과를 보인 균주(菌株) 2번 토양(土壤)에서 분리(分離)한 YCK 141 이었다. 3. 토착근류균(土着根瘤根)의 혈청학적(血淸學的) 집단(集團)은 6종(種)으로써 혈청형(血消型) YCK 117(12균주(菌株))이 가장 많았고, 다음으로 USDA 110 (5균주(菌株)), USDA 123(5균주(菌株))>YCK 150(4균주(菌株))>YCK 141 (3균주(菌株))>YCK 226(1균주(菌株)) 순(順)이었으며, 토양별(土壤別)로는 1번 토양(土壤)(1종(種))을 제외(徐外)한 2번 (5종(種))과 3번 토양(土壤)(5종(種))에 분산(分散) 분포(分布)되어 있었다. 4. 공시토양(供試土壞)중 미경작지(未耕作地)인 1번 토양(土壤)에서 분리(分離)한 균주(菌株)들은 대두(大豆) 접종효과에 있어서 서로간에 균질성(均質性)을 보였을 뿐만 아니라, 혈청학적(血淸學的) 특성(特性)에 있어서도 모두가 YCK 117 혈청집단(血淸集團)에 속하는 동질성(同質性)을 보였다.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1187-1196
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• 2013

Global warming will have far-reaching effects on our ecosystem. However, its effects on Antarctic soils have been poorly explored. To assess the effects of warming on microbial abundance and community composition, we sampled Antarctic soils from the King George Island in the Antarctic Peninsula and incubated these soils at elevated temperatures of $5^{\circ}C$ and $8^{\circ}C$ for 14 days. The reduction in total organic carbon and increase in soil respiration were attributed to the increased proliferation of Bacteria, Fungi, and Archaea. Interestingly, bacterial ammonia monooxygenase (amoA) genes were predominant over archaeal amoA, unlike in many other environments reported previously. Phylogenetic analyses of bacterial and archaeal amoA communities via clone libraries revealed that the diversity of amoA genes in Antarctic ammonia-oxidizing prokaryotic communities were temperature-insensitive. Interestingly, our data also showed that the amoA of Antarctic ammonia-oxidizing bacteria (AOB) communities differed from previously described amoA sequences of cultured isolates and clone library sequences, suggesting the presence of novel Antarctic-specific AOB communities. Denitrification-related genes were significantly reduced under warming conditions, whereas the abundance of amoA and nifH increased. Barcoded pyrosequencing of the bacterial 16S rRNA gene revealed that Proteobacteria, Acidobacteria, and Actinobacteria were the major phyla in Antarctic soils and the effect of short-term warming on the bacterial community was not apparent.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1213-1222
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• 2009

The search for diverse plant growth-promoting (PGP) diazotrophic bacteria is gaining momentum as efforts are made to exploit them as biofertilizers for various economically important crops. In the present study, 17 diazotrophic strains belonging to eight different genera isolated from rice paddy fields were screened for multiple PGP traits and evaluated for their inoculation effects on canola and rice plants. All of the strains tested positive for 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity and production of indole 3-acetic acid (IAA) and ammonia ($NH_3$). Additionally, four of the strains were able to solubilize phosphorus (P), five tested positive for zinc (Zn) solubilization and sulfur (S) oxidation, and eight strains produced siderophores. Based on the presence of multiple PGP traits, 10 strains were selected for inoculation studies. Treatment with Herbaspirillum sp. RFNB26 resulted in maximum root length (54.3%), seedling vigor, and dry biomass in canola, whereas Paenibacillus sp. RFNB4 exhibited the lowest activity under gnotobiotic conditions. However, under pot culture conditions, Paenibacillus sp. RFNB4 significantly increased plant height and dry biomass production by 42.3% and 29.5%, respectively. Canola plants and rhizosphere soils inoculated with Bacillus sp. RFNB6 exhibited significantly higher nitrogenase activity. In greenhouse experiments, Serratia sp. RFNB18 increased rice plant height by 35.1%, Xanthomonas sp. RFNB24 enhanced biomass production by 84.6%, and rice rhizosphere soils inoculated with Herbaspirillum sp. RFNB26 exhibited the highest nitrogenase activity. Our findings indicate that most of the selected strains possess multiple PGP properties that significantly improve the growth parameters of the two plants when tested under controlled conditions.