Phosphorus Accumulation and Utilization Efficiency in Soybean Plant under Atmospheric CO₂ Enrichment

Sa, Tongmin,Kim, Jong-Soo 한국응용생명화학회 2001 Journal of Applied Biological Chemistry (J. Appl. Vol.44 No.1

Soybean plants(Glycine max [L.] merr.) inoculated with Bradyrhizobium japonicum MN110 were grown in growth chambers under 400 or $800{\mu}l{\cdot}l^{-1}$ atmospheric $CO_2$ and harvested at 25, 28, 32, and 35 DAT to examine the effect of $CO_2$ enrichment on phosphorus accumulation, uptake, and utilization efficiency during vegetative growth. Phosphorus concentration in leaf was lower in high $CO_2$ plant by 47% at 25 DAT and 34% at 35 DAT than those in the control plant but phosphorus concentrations in stem, root and nodule were not affected by $CO_2$ enrichment. Total phosphorus accumulation increased 3.9-fold in high $CO_2$ plant and 3.2-fold in the control plant between 25 and 35 DAT. Elevated $CO_2$ caused a decrease in the whole plant phosphorus concentration by 35%, which was due almost entirely to a decrease in the phosphorus concentration of leaves. $CO_2$ enrichment increased phosphorus utilization efficiency in the whole plant by 70% during the experimental period. Plants exposed to high $CO_2$ had larger root systems than under ambient $CO_2$, but high $CO_2$ plants had lower P-uptake efficiency. Averaged over four harvests, plants at high $CO_2$ had 38% larger root mass that was more than offset the 20% lower efficiency of P-uptake and accounted for increased phosphorus accumulation by high $CO_2$ plant. These results suggest that the reduced phosphorus concentration in soybean plant under $CO_2$ enrichment may be an acclimation response to high $CO_2$ concentration or enhanced starch accumulation, resulting in the plants to have a lower phosphorus requirement on a unit dry weight basis or a high phosphorus utilization efficiency under these conditions.

Research Trends on Plant Associated Beneficial Bacteria as Biofertilizers for Sustainable Agriculture

Tongmin Sa(사동민),Puneet Singh Chauhan 한국토양비료학회 2009 한국토양비료학회지 Vol.42 No.S2

생물비료는 아직도 한국에서는 생소한 용어다. 한국에서 생물비료라 함은 식물추출액, 퇴비류- 다양한 형태의 미생물 혼합제 등으로 인식되고 있다. 그러나 최근에는 식물영양요소의 흡수나 이용도를 증진시키는 토양미생물 사용으로 언급하기도 한다. 본 개관은 식물성장을 증진시키는 것으로 알려진 PGPR 서로 다른 기작과 실질적 역할에 대하여 검토하였다. The sustainability of conventional agriculture which is characterized by input dependent an ecologically simplified food production system is vague. Chemicals and present practices used in agriculture are not only costly but also have widespread implications on human and animal health, food quality and safety and environmental quality. Thus there is a need for alternative farming practices to sustain food production for the escalating population and conserve environment for future generations. The present research scenario in the area of plant microbe interactions for maintainingsustainable agriculture suggests that thelevel of internal regulation in agro-ecosystems is largely dependent on the level of plant and microbial diversity present in the soil. In agro-ecosystems, biodiversity performs a variety of ecological services beyond the production of food, including recycling of nutrients, regulation of microclimate and local hydrological processes, suppression of undesirable organisms and detoxification of noxious chemicals. Controlling the soil microflora to enhance the predominance of beneficial and effective microorganisms can help improve and maintain soil chemical and physical properties. The role of beneficial soil microorganisms in sustainable productivity has been well construed. Some plant bacteria referred to as plant growthpromoting rhizobacteria (PGPR) can contribute to improve plant growth, nutrient uptake and microbial diversity when inoculated to plants. Term PGPR was initially used to describe strains of naturally occurring non-symbiotic soil bacteria have the ability to colonize plant roots and stimulateplant growth. PGPR activity has been reported in strains belonging to several other genera, such as Azotobacter, Azospirillum, Arthrobacter, Bacillus, Burkhokderia, Methylobacterium, and Pseudomonas etc. PGPR stimulate plant growth directly either by synthesizing hormones such as indole acetic acid or by promoting nutrition, for example, by phosphate solubilization or more generally by accelerating mineralization processes. They can also stimulate growth indirectly, acting as biocontrol agents by protecting the plant against soil borne fungal pathogens or deleterious bacteria. Present review focuses on some recent developments to evolve strategies for better biotechnological exploitation of PGPR’s.

Enhancing Fertilizer Use Efficiency through Microbial Inoculants for Agricultural Green Productivity

Tongmin Sa 한국토양비료학회 2010 한국토양비료학회 학술발표회 초록집 Vol.2010 No.5

대기 CO2 상승시 인산공급이 식물체의 광합성 및 질소고정에 미치는 영향

사동민 ( Tongmin Sa ) 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.40 No.2

The objective of this study was to examine the effect of phosphorus deficiency on nitrogen fixation and photosynthesis of nitrogen fixing soybean plant under CO₂ enrichment condition. The soybean plants(Glycine max [L.] Merr.) inoculated with Bradyrhizobium japonicum MN 110 were grown with P-stressed(0.05 mM-P) and control(1 mM-P) treatment under control(400 ㎕/L CO₂) and enrichment(800 ㎕/L CO₂) enviromental condition in the phytotron equipped with high density lamp(1000 μEm ^(-2)S^(-1)) and 28/22℃ temperature cycle for 35 days after transplanting(DAT). At 35 DAT, phosphorus deficiency decreased total dry mass by 64% in CO₂ enrichment condition, and 51% in control CO₂ condition. Total leaf area was reduced significantly by phosphorus deficiency in control and enriched COL condition but specific leaf weight was increased by P deficiency. Phosphorus deficiency significantly reduced photosynthetic rate(carbon exchange rate) and internal CO₂ concentration in leaf in both CO₂ treatments, but the degree of stress was more severe under CO₂ enrichment condition than under control CO₂ environmental condition. In phosphorus sufficient plants, CO₂ enrichment increased nodule fresh weight and total nitrogenase activity(acetylene reduction) of nodule by 30% and 41% respectively, but specific nitrogenase activity of nodule and nodule fresh weight was not affected by CO₂ enrichment in phosphorus deficient plant at 35 DAT. Total nitrogen concentrations in stem, root and nodule tissue were significantly higher in phosphorus sufficient plant grown under CO₂ enrichment, but nitrogen concentration in leaf was reduced by 30% under CO₂ enrichment. These results indicate that increasing CO₂ concentration does not affect plant growth under phosphorus deficient condition and phosphorus stress might inhibit carbohydrate utilization in whole plant and that CO₂ enrichment could not increase nodule formation and functioning under phosphorus deficient conditions and phosphorus has more important roles in nodule growth and functioning under CO₂ enrichment environments than under ambient condition.

인산결핍 조건하에서 질소고정식물체내의 Ureide 분배

사동민 ( Tongmin Sa ) 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.40 No.3

Soybean plants inoculated Bradyrhizobium japonicum MN 110 were grown in outdoor perlite pots with nitrogen free nutrient solution containing 1.0 mM-P(control) and 0.05 mM-P(stress) and harvested at 28, 35, 42 and 49 days after transplanting (DAT) to examine the effect of phosphorus deficiency on ureide concentration of and distribution to different plant organ in nitrogen fixing soybean plant during the vegetative growth. Total dry mass of control plants increased 8.9 fold and that of phosphorus deficient plant increased 2.7 fold during the experimental period. Phosphorus deficiency reduced total phosphorus and nitrogen accumulation by 80%, 40% respectively, at 28 DAT and 93%, 84%, respectively, at 49 DAT. Nitrogen concentration was reduced by phosphorus deficiency in all tissues with leaf and stem tissues affected to a greater degree than nodule and root tissues at every sampling date. Phosphorus deficiency significantly reduced soluble reduced-N and ureide-N concentration in leaf and stem but did not affect those in root. The proportion of soluble reduced-N in leaf was reduced from 60% to 50% but increased from 10% to 20% in the roots. The proportion of ureide-N in leaf of control plants was higher than that in phosphorus deficient plants, whereas, roots of phosphorus deficient plants contained a higher proportion of ureide-N than those of control plants. These indicated that phosphorus deficiency not only inhibit nitrogen fixation of nodules but also restrict the translocation of fixed nitrogen out of the root system into the xylem.

Research Trends on Plant Associated Beneficial Bacteria as Biofertilizers for Sustainable Agriculture: An Overview

사동민,Sa, Tongmin,Chauhan, Puneet Singh 한국토양비료학회 2009 한국토양비료학회지 Vol.42 No.S2

생물비료는 아직도 한국에서는 생소한 용어다. 한국에서 생물비료라 함은 식물추출액, 퇴비류-다양한 형태의 미생물 혼합제 등으로 인식되고 있다. 그러나 최근에는 식물영양요소의 흡수나 이용도를 증진시키는 토양미생물 사용으로 언급하기도 한다. 본 개관은 식물성장을 증진시키는 것으로 알려진 PGPR 서로 다른 기작과 실질적 역할에 대하여 검토하였다. The sustainability of conventional agriculture which is characterized by input dependent and ecologically simplified food production system is vague. Chemicals and present practices used in agriculture are not only costly but also have widespread implications on human and animal health, food quality and safety and environmental quality. Thus there is a need for alternative farming practices to sustain food production for the escalating population and conserve environment for future generations. The present research scenario in the area of plant microbe interactions for maintaining sustainable agriculture suggests that the level of internal regulation in agro-ecosystems is largely dependent on the level of plant and microbial diversity present in the soil. In agro-ecosystems, biodiversity performs a variety of ecological services beyond the production of food, including recycling of nutrients, regulation of microclimate and local hydrological processes, suppression of undesirable organisms and detoxification of noxious chemicals. Controlling the soil microflora to enhance the predominance of beneficial and effective microorganisms can help improve and maintain soil chemical and physical properties. The role of beneficial soil microorganisms in sustainable productivity has been well construed. Some plant bacteria referred to as plant growth-promoting rhizobacteria (PGPR) can contribute to improve plant growth, nutrient uptake and microbial diversity when inoculated to plants. Term PGPR was initially used to describe strains of naturally occurring non-symbiotic soil bacteria have the ability to colonize plant roots and stimulate plant growth PGPR activity has been reported in strains belonging to several other genera, such as Azotobacter, Azospirillum, Arthrobacter Bacillus, Burkhokderia, Methylobacterium, and Pseudomonas etc. PGPR stimulate plant growth directly either by synthesizing hormones such as indole acetic acid or by promoting nutrition, for example, by phosphate solubilization or more generally by accelerating mineralization processes. They can also stimulate growth indirectly, acting as biocontrol agents by protecting the plant against soil borne fungal pathogens or deleterious bacteria. Present review focuses on some recent developments to evolve strategies for better biotechnological exploitation of PGPR's.

아산지역 논 토양의 이화학적 특성 연구

허진욱,사동민 선문대학교 자연과학대학 1998 자연과학대학 논문집 Vol.1 No.-

충남 아산지역 논 토양의 양분특성 및 중금속함량을 조사하기 위하여 50개 지역의 토양을 채취하여 유효인산량, 토양 pH, 유기물함량, 치환성 양이온함량 및 중금속함량을 측정하였다. 조사토양의 pH는 4.68~6.08 범위에 있었으며 유기물함량 및 유효인산의 평균치는 각각 1.95% 및 566ppm으로 나타났다. 치환성 양이온함량의 평균치는 Ca: 5.19, Mg: 1.54 및 K: 0.66me/100g · soil 이었다. 또한 토양중금속함량은 Cd: 0.74-0.38, Pb: 0.03-0.32 및 Zn: 1.4-5.6 mg/kg으로 조사되었다. 이상의 결과로 아산지역의 논 토양은 이화학적 성질이 전국토양 평균치보다 우수하였으며 작물 생산에 유해할 정도의 중금속 오염은 없는 것으로 판단되었다. Soil-pH, available-P concentration, organic matter content, exchangeable cation and heavy metal contents were measured to examine the physicochemical properties in poddy soils of Asan area. Soil-pH ranged from 4.68 to 6.08 and organic matter and available-P content were 1.9% and 566ppm, respectively. The concentrations of exchangeable Ca, Mg and K were 5.19, 1.54 and 0.66me/100g soil. respectively. The heavy metal Concentration were Cd; 0.74-0.38, Pb; 0.03-0.32 and Zn;1.4~5.6mg/kg, respectively. These results showed that the nutrient content in Asan area were higher than those of the average in Korean soils and the heavy metal concentrations were lower than the critical level for crop production.

토양 중금속류 검정을 위한 비색법 이용 연구

양진철,사동민 선문대학교 자연과학대학 1998 자연과학대학 논문집 Vol.1 No.-

농업환경의 보전과 양질의 농산물 생산을 위하여 토양의 중금속함량을 비색법을 이용하여 간편하고 신속하게 정량 할 수 있는 방법을 개발하고자 32점의 토양을 대상으로 토양의 중금속 함량, 토양의 이화학적 성질과 중금속 함량과의 관계 및 가존의 방법(ICP 분석)과 비색법의 상관관계를 검토하였다. 일반 농경지 토양의 Cd. Cr, Cu, Pb, Ni 및 Zn의 함량은 각각 0.004~ 0. 196ppm, 0.063-0.301ppm, 0~1.360ppm, 0.08- 1. 90ppm, 0.02-0.3ppm 및 0.205 ~3.55ppm으로 환경보호법령의 농경지 토양오염기준 및 대책기준의 농도보다 낮게 나타났다. 토양의 이화학적 성질에 따른 두 방법간의 상관관계는 각각의 중금속에 따라 차이를 나타내며, Cr은 pH가 5.3 미만, 유효인산량 80ppm 미만, 치환성-Ca 3.4me/100g 미만, 치환성-K 0.2me/100g 미만, 치환성-Mg 0.8me/100g 미만의 토양 측정시 방법간 고도의 유의성을 나타내었다. Cu는 pH 5.8 이상, 유기물함량 3.5% 이상, 치환성-Ca 0.695 me/100g 이상, 치환성-K 0.685 me/100g 이상의 토양에서 상호방법 측정치간에 고도의 유의성을 나타내었다. 일 반 농경지의 토양 Zn 정량시 모든 토양에서 기존의 방법과 비색법과의 측정치간에 유의성 있는 상관관계 (r²=0.793)를 보여 간이 비색법 사용이 가능한 것으로 나타났다. To develop new Quick method for measurement of heavy metal concentrations in soil, color developing method applied to heavy metal determination and the correlation between soil physicochemical properties and soil heavy metal concentration, the correlation between ICP method and new quick color developing methods were examined. The concentrations of Cd, Cr, Cu, Pb, Ni and Zn in farming soils ranged 0.004~0.196ppm, 0.063~0.301ppm, 0~1.360ppm, 0.08~1.90ppm, 0.02~0.3ppm and 0.205~3.55ppm, respectively, and lower than those of critical limit in Act of environmental soil conservation. The correlation between two methods was affected by soil physicochemical properties, Cr in the soils with pH<5.3, Ava-P concentration<80ppm, exch-Ca<3.4me/100g, exch-Mg<0.8me/100g and Cu in the soils with pH>5.8, O.M content 3.5%>, exch-Ca>0.695me/100g, exch-K>0.685s showed higher correlation between two methods than that in other soils. The correlation of Zn concentration between determined by ICP method and quick color developing method was significant and this method could be applied for Zn measurement in soil with wide range of physicochemical properties.

자연녹지 토양 미생물 생태 변화 연구

양순혜,사동민 선문대학교 자연과학대학 1999 자연과학대학 논문집 Vol.2 No.-

자연녹지의 미생물 생태 변화를 살펴보기 위하여 오대산, 남산, 청량산, 마니산 및 창덕궁 후원의 신갈나무림 서어나우림, 소나무림, 리기다 소나무림 및 아까시나무심의 표토와 심토를 채취하여 미생물 밀도, 분포 및 다양성 지수를- 조사하였다. 총균수는 표토에서 서어나무림 1,97×10^(7), 신갈나무림 2.64×10^(7), 소나무림 3.32×10^(7), 아까시나무림 5,37×10^(7), 리기다소나무림 2,60×10^(7) c.f.u,/g soil였다. 사상균의 총균수 는 지역별로 남산 3.54×10^(6), 오대산 0.69×10^(6), 마니산 0,32×10^(6), 청량산 0.29×10^(6), 창덕궁 0.21×10^(6) c.f.u/g soil이었다. 다양성 지수는 지역별로는 오대산(0.4897) > 마니산(0.4638) > 남산(0.3699) > 창덕궁 (0.3577) > 청량산(0,2847) 순서였으며, 서식림별로는 소나무림((),4772) > 서어나무림(0.4517) > 신갈나무림 ((),4316) > 리기다소나무림(0.3366) > 아까시나무럼(0,3232)으로 나타났다. Microbial density, proportion and diversity in surface and sub soil under Queraus mongolica, Carpinus laxiflora, Pinus densiflora, Robinia Pseudoacacia, Pinus rigida of Mt. Nam, Mt. Odea, Mt. Manee, Mt, Chungyand and Chanduckgung were examined. Total microbial density were Carpinus laxiflora 1.97×10^(7) c.f.u./g-soil, Quercus mongolica 2.64×10^(7) Pinus densiflora 3.32×10^(7) Robinia Pseudoacacia 5.37×10^(7) Pinus; rigida 2.60×10^(7) c.f.u./g soil in surface soil. Density of fungi were Mt. Nam 3.54×10^(6), Mt. Odea 0.69×10^(6), Mt. Manee 0.32×10^(6). Mt. Chungyang 0.29×10^(6) Changduckgung 0.21×10^(6) c.f.u./g soil in location. Microbial diversity were Mt. 0dea(0.4897) > Mt. Manee(0.4638) > Mt. Nam(0.3699) > Changduckgung(0.3577) > Mt. Chungyang(0.2847) in location and Pinus densiflora(0.4772) > Carpinus laxifloa(0.4517) > Quercus mpgolica(0.43l6) > Pinus rigida(0.3366) > Robinia Pseudoacacia(0.3232) in forest.

Pink Pigmented Facultative Methylotrophic Bacteria (PPFMs)

Munusamy Madhaiyan,Tongmin Sa(사동민),Jai-Joung Kim(김재정) 한국토양비료학회 2004 한국토양비료학회지 Vol.37 No.4