• Journal of Microbiology and Biotechnology
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• 제26권10호
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• pp.1755-1764
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• 2016

The application of Bacillus sp. in the biological control of plant soilborne diseases has been shown to be an environmentally friendly alternative to the use of chemical fungicides. In this study, the effects of bioorganic fertilizer (BOF) fortified with Bacillus amyloliquefaciens SQY 162 on the suppression of tomato bacterial wilt were investigated in pot experiments. The disease incidence of tomato wilt after the application of BOF was 65.18% and 41.62% lower at 10 and 20 days after transplantation, respectively, than in the control condition. BOF also promoted the plant growth. The SQY 162 populations efficiently colonized the tomato rhizosphere, which directly suppressed the number of Ralstonia solanacearum in the tomato rhizosphere soil. In the presence of BOF, the activities of defense-related enzymes in tomato were lower than in the presence of the control treatment, but the expression levels of the defense-related genes of the plants in the salicylic acid and jasmonic acid pathways were enhanced. It was also found that strain SQY 162 could secrete antibiotic surfactin, but not volatile organic compounds, to suppress Ralstonia. The strain could also produce plant growth promotion compounds such as siderophores and indole-3-acetic acid. Thus, owing to its innate multiple-functional traits and its broad biocontrol activities, we found that this antagonistic strain isolated from the tobacco rhizosphere could establish itself successfully in the tomato rhizosphere to control soilborne diseases.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.118-126
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• 2020

Silicon and phosphorus are elements that are beneficial for plant growth. Despite the abundant availability of silicate and phosphate in the Earth's crust, crop nutritional requirements for silicon and phosphorus are normally met through the application of fertilizer. However, fertilizers are one of the major causes of heavy metal pollution. In our study, we aimed to assess silicate and phosphate solubilization by the bacteria Enterobacter ludwigii GAK2, in the presence and absence of phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), to counteract cadmium stress in rice (Oryza sativa L). Our results showed that the GAK2-treated rice plants, grown in soil amended with phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), had significantly reduced cadmium content, and enhanced plant growth promoting characteristics including fresh shoot and root weight, plant height, and chlorophyll content. These plants showed significant downregulation of the cadmium transporter gene, OsHMA2, and upregulation of the silicon carrier gene, OsLsi1. Moreover, jasmonic acid levels were significantly reduced in the GAK2-inoculated plants, and this was further supported by the downregulation of the jasmonic acid related gene, OsJAZ1. These results indicate that Enterobacter ludwigii GAK2 can be used as a silicon and phosphorus bio-fertilizer, which solubilizes insoluble silicate and phosphate, and mitigates heavy metal toxicity in crops.

• 한국자원식물학회지
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• 제22권3호
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• pp.209-214
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• 2009

To facilitate the introgression of F. esculentum into the traits of F. homotropicum, several accessions of the hybrids between these two species were pollinated with F. esculentum as the recurrent parent. The embryo in vitro rescue was performed to increase the recovery of backcross progenies. The $F_{2}$ generation was more amenable than $F_{1}$ hybrids to produce backcross progenies. The $F_{1}$ hybrids were backcrossed twice with common buckwheat (pin-type F. esculentum) (recurrent backcrossing). Also, alternate backcrosses with common buckwheat and F. homotropicum (congruity backcrossing) were carried out. Pollen tube growth of BC$F_{1}$ ${\times}$ F. esculentum (thrum) and F. homotropicum ${\times}$ BC$F_{1}$ was the disturbed penetration exceeded for all initial interspecific hybrids, and its requirement was proportionally lower when the common buckwheat was used as the recurrent parent and as the last parent of congruity hybrids. Effects of both common buckwheat and F. homotropicum on seed success rate for hybridization were observed. Growth of hybrid embryos before rescue, regeneration of mature hybrids all increased recurrent and congruity backcrosses and inter-crosses between $F_{1}$ plants and selected fertile plants of the second congruity backcrosses.

• 한국약용작물학회지
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• 제2권3호
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• pp.246-250
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• 1994

반하(半夏)의 엽절편(葉切片)을 배양(培養)하여 유도(誘導)한 Callus로부터 식물재분화(植物再分化)에 미치는 온도(溫度)와 광조건(光條件) 그리고 기내(器內) 괴경(塊莖) 비대(肥大)를 위한 배지내(培地內) 실소원(室素源)의 영향(影響) 등에 대하여 검토(檢討)한 결과(結果)는 다음과 같다. 1. 엽절(葉切)으로부터의 Callus 형성(形成)과 기관분화(器官分化)에는 2, 4-D 또는 NAA의 첨가(添加)가 IAA 첨가(添加)보다 좋았으며, 배양조건(培養條件)으로는 $26^{\circ}C$에서 8시간(時間)/ 일(日), 명배양(明培)하는 것이 효과적(效果的)이었다. 2. Callus로부터 식물체(植物體)를 재분화하기 위한 적정배지(適正培地)는 MS 배지(培地)에 BA $2mg/{\ell}$를 첨가(添加)하였을 때 좋았으며, 배양환경(培養環境)은 $26^{\circ}C$에서 $16{\sim}24$시간(時間)/일(日) 명배양(明培養)시키는 것이 좋았다. 3. 배지내(培地內)에 $KNO_3\;3.0g/{\ell}$처리(處理)하였을 때 식물체(植物體) 재분화배지(再分化培地) MS+BA $2mg/{\ell}$에 비하여 기내괴경(器內塊莖)의 비대(肥大)가 2.5배(培) 이상(以上)에 달하였다.

• 한국토양비료학회지
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• 제37권1호
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• pp.41-45
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• 2004

충북지역의 근권 토양으로부터 선발한 인산가용화 균인 Pantoea agglomeraans와 인광석을 복합처리하여 벼(Oryza sativa L.)의 생육 및 인산 흡수량에 미치는 영향을 온실내에서 실험하였다. 본 실험은, 종자에 박테리아를 적용시킨 것(bactenzation), 독립 세포 및 고정화된 세포(immobilized cell)를 접종시킨 후, 인광석 1 g과 2.5 g을 각각 시비한 6처리구와 무처리구로 나누어 비교 실험하였다. 인산가용화균을 접종한 처리구가 무처리구에 비하여 벼의 생육 및 인산 흡수량을 증대하는 경향을 나타냈으며, 특히 1 g의 인광석과 고정화된 Pantoea agglomerans를 접종한 처리구에서 다른 처리구들에 비해 가장 우수한 결과를 나타내었다. Pot 충진물내의 유효인산 농도 또한 미생물 접종 처리구에서 증가하였으며, 벼에 흡수된 전인산량과 정의 상관관계가 성립함을 알 수 있었다.

• 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.

• 한국수산과학회지
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• 제54권3호
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• pp.311-317
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• 2021

Growth differences in Caulerpa okamurae thallus parts and the effects of apex removal on growth were examined. Erect fronds, stolons, and erect fronds with stolons (erect+stolon) were grown for 14 days, whereas erect fronds without and with apex removal (-A and +A fronds, respectively), were grown for 25 days. The relative growth rates (RGR) of C. okamurae thallus parts ranged from 1.91% to 4.93% day^-1 with maximal and minimal RGR for the stolon and erect+stolon treatments, respectively. Over the 25 days in culture, the -A fronds showed a higher RGR (2.48% day^-1) than the +A fronds (1.96% day^-1). More new erect fronds and stolons were produced by -A fronds than those by +A fronds. In addition, basal cutting of erect C. okamurae fronds resulted in a greater plant length increase than that obtained from top cutting. These findings indicate that vegetative growth is common in C. okamurae, which has excellent wound healing ability, and cutting damage to erect fronds may stimulate enhanced vegetative growth. Thus, we suggest that stolons and erect fronds of C. okamurae could be used as seeding materials for large scale cultivation. Furthermore, this edible species could be a potential seaweed resource for rapid skin regeneration cosmetics.

• 한국환경농학회지
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• 제42권1호
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• pp.14-20
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• 2023

Light is an important factor that influences the growth and development of flowering plants. The present study investigated the effects of in vitro acclimatization to different light colors (white light (WL; control), blue light (BL; 447 nm), green light (GL; 519 nm), and red light (RL; 667 nm)) on the growth of petunia (Petunia hybrida) and of hardening cultivation of plant transferred form in vitro to a greenhouse under sunlight. Compared to the control, the shoot length and leaf width of Petunia increased by 42% and 11.7%, respectively, after acclimatization to BL and the shoot growth increased by 29.3% after acclimatization to RL. The chlorophyll and carotenoid contents after acclimatization to BL and GL were 16.7% and 11.3% higher, respectively, and 14.4% and 11.9% higher, respectively, than those in the control. During greenhouse cultivation, the shoot length increased by 16.7% and 11.3%, respectively, after acclimatization to BL and RL, respectively, and the leaf length and leaf width increased by 14.4% and 11.9%, respectively, after acclimatization to GL. While dry weight of root of GL and BL was not significant difference in vitro, increased by 59.0% and 22.9% ex vitro than that of WL. Thus, acclimatization to BL increased the shoot growth and leaf chlorophyll contents, and acclimatization to GL and RL enhanced shoot and root growth, in petunia.

• 한국자원식물학회지
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• 제27권5호
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• pp.546-555
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• 2014

연구의 최종 목표는 실내의 공간과 특성에 따라 효율적으로 실내공기질을 향상시킬 수 있는 식물 녹화와 바이오필터를 통합한 시스템의 개발이다. 그러나 이러한 목표를 달성하기 위해서는 바이오필터 시스템의 적절한 공기정화량에 대한 용량 설계에 중요한 영향을 주는 일정한 압력손실량과 토양수분 함량과 같은 여러 가지 요구사항들이 충족되어야 한다. 따라서 본 기초 연구는 바이오필터의 토양 내 균일한 분포를 갖는 토양수분 함량과 압력손실량을 유지하고 정상적인 식물 생장 특히 바람에 의한 근권부 스트레스를 받지 않도록 풍속을 적절히 조절하고, 바이오필터 내 초기 토양수분 함량이 일정하게 유지되어 안정성을 확보하기 위해 수행되었다. 본 실험에서는 평면형 바이오필터 모델을 설계하여 제작하고 세 가지 풍속(1, 2, $3cm{\cdot}sec^{-1}$)에 따른 바이오필터의 공기정화량, 공기체류시간, 기액비를 산출하였다. 또한 세가지 풍속에 따라 바이오필터 내 토양층을 통과하여 배출된 가습공기의 상대습도, 압력손실량, 토양수분 함량을 측정하고, 이 바이오필터 내에서 자란 상추와 더 피고사리의 생육을 평가하였다. 풍속 실험의 결과, 풍속 $3cm{\cdot}sec^{-1}$가 상대습도, 토양수분 함량, 식물생육을 유지하기에 가장 적절하였다. 따라서 다음 실험에서는 풍속을 $3cm{\cdot}sec^{-1}$로 고정하고 두 가지 수준의 초기 토양수분 함량(저수준 18.5%, 고수준 28.7%) 조건에서 바이오필터를 가동한 처리구와 바이오필터를 가동하지 않은 대조구(초기 토양수분 함량 29.7%)를 설정하고, 바이오필터 내 토양층을 통과하여 배출된 가습공기의 상대습도, 압력손실량, 토양수분 함량과 바이오필터 내에서 자란 상록넉줄고사리의 생육을 평가하였다. 이 실험 결과는 첫 번째 실험 결과와 유사하였으며 상대습도, 토양수분 함량, 압력손실량이 일정한 수준을 유지하였다. 또한 세 가지 초기 토양수분 함량에 따른 상록넉줄고사리의 생육도 유의성 있는 차이를 나타내지 않았다. 그러나 두 가지의 바이오필터 처리구는 대조구에 비해 건물중이 다소 증가된 것을 알 수 있었다. 따라서 주요 물리적 요소인 토양수분 함량과 압력손실량을 유지할 수 있는 본 바이오필터 시스템의 안정성은 가까운 미래에 보다 발전된 일체형 바이오필터 모델 설계에 적용될 수 있을 것으로 판단된다.

• 한국작물학회지
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• 제38권3호
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• pp.213-218
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• 1993

모시풀의 생장촉진을 위한 생장조절제의 적정 살포시기, 회수 및 농도를 알아보기 위한 시험결과를 요약하면 다음과 같다. 1. 모시풀의 생장점에 Gibberellin을 살포하면 줄기의 신장에 효과가 켰으며 경장 50cm 때의 1회 살포에 비하여 경장 50및 100cm때의 2회, 50, 100 및 150cm 때의 3회로 살포회수가 많을수록 그 신장도가 켰으며 생육초기보다 후기살포가 더욱 효과적이었다. 2. Gibberellin 농도는 50ppm 보다는 100～300ppm액 살포에서 줄기의 신장이 뚜렷하였으며, 이는 절간장의 신장에서 연유되었고, 절수의 증가는 거의 없었다. 3. 어느 농도에서나 1회 살포의 경우는 엽의 생장도 다소 좋아지는 경향이나, 2회, 3회로 살포회수가 많고 농도가 높을수록 오히려 엽의 생장에 저해를 받는듯 하였다. 4. 섬유수량은 Gibberellin 100ppm 3회 살포의 경우 가장 다수였으며 섬유비율에 있어서도 무처리구의 4.6%에 비하여 5.3%로서 가장 높았다. 5. Atonic은 모시풀의 줄기신장 효과가 Gibberellin에 미치지 못하였으며, 생장조절제 처리는 모시풀의 인피섬유의 발달에도 효과가 있는 것으로 생각되었다.