• 제목/요약/키워드: Nitrogen fixation

검색결과 269건 처리시간 0.022초

Relationship between Nodulating Characters and Yield Components in Supernodulating Soybean Mutants

  • Park Sei Joon;Youn Jong Tag;Kim Wook Han;Lee Jae Eun;Kwon Young Up;Shin Jin Chul;Seong Rak Chun
    • 한국작물학회지
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    • 제50권1호
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    • pp.5-10
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    • 2005
  • This experiment was conducted to clarify the functions of supernodulating characters on seed yield determination through the comparison of agricultural traits of supernodulating soybean mutants, Sakukei4, SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2. The plant dry weights of supernodulating mutants, Sakukei4 and SS2-2, were $52\%$ and $61\%$ of their wild type parents at full seed stage (R6). However, the relative growth rate (RGR) from the pod set stage (R3) to R6 of Sakukei4 was 0.022 g/g/day and that of SS2-2 was 0.016 g/g/day, which were higher than those of their parents. Nodule number and dry weight were increased in two supernodulating mutants by the R6 stage. The nitrogen concentrations of leaf, petiole and stem of Sakukei4 were higher than those of Enrei. SS2-2 showed higher nitrogen concentration in petiole than Shinpaldalkong2 had. The positive correlations were appeared between nodule dry weight, plant dry weight and pod number, in two supernodulating mutants during the period from R3 to R6 stage. Although all of the yield components and seed yield were lower in two supernodulating mutants than their parents at the stage of full maturity (R8), the harvest index was higher in supernodulating mutants. The increasing rates of pod number to stem dry weight in two supernodulating mutants showed the higher than those of two their parents at R8 stage. In conclusion, the relative growth rates during the early to the middle reproductive growth period were higher in supernodulating mutants than the wild types. This could be resulted in an increase in pod number. The increase of relative growth rate was the result of the successive supplement of nitrogen source from biological nitrogen fixation (BNF) of nodules during the middle reproductive growth period in supernodulating mutants.

콩의 생육, 근류형성, 질소고정에 있어서 품종간 차이 II. 등숙기간중 근 및 근류 당함량의 경시적 변화 (Studies on Varietal Differences in Growth, Nodulation and Nitrogen Fixation in Soybeans Glycine max (L.) Merril II. Changes in Sugar Concentration of Root and Nodule During Reproductive Stage)

  • 김석동
    • 한국작물학회지
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    • 제32권4호
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    • pp.447-454
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    • 1987
  • 본 연구는 생태적, 생리적 특성이 다른 콩5품종, 즉 조숙성의 예계 7003, SS79168 및 만숙성의 동북 7006, 백운콩, 장백콩을 공시하여 등숙기간중 영양영리학적인 관점에서 근과 근류의 당함량과 질소고정활성과의 관련성을 해명하기 위하여 Acetylene 환원능 (ARA ) 등을 조사하였다. 기히 공시품종중 예계 7003는 노화가 지연되는 특성(delayed leaf sen-escence, DLS )을 갖는 품종이다. 본보에서는 얻어진 결과중 근 및 근류 당의 경시적 변동과 질소고정활성과의 관계를 보고하며 이를 요약하면 다음과 같다. 1. 조숙성 품종에서의 근중 환원당 농도는 $R_{7}$까지 변화 없이 경과하다가 다소 상승하는 경향이 인정되었다. 만숙성 품종에서는 $R_{6}$ 까지 상승하고, 그 후 급등히 저하하였다. 근의 비환원당 농도는 DLS 의 예계7003 이외 품종에서는 $R_{6}$ 까지 큰 변화가 없었고, 그 후 급속히 감소하였으나 엽신의 황화가 지연된 예계7003에서는 그 저하가 인정되지 아니하였다. 2. 근류의 환원당 농도는 품종의 조만성에 관계없이 $R_{6}$ 까지 커다란 변화는 없었고, 그 직후 질소고정활성의 급격한 저하가 나타난 $R_{6.5}$ 에서 일시적으로 상승하였다. 이것은 질소고정활성이 에너지원(당)의 공급조건에 의하여 규제될 뿐만 아니라, 고정질소에 대한 요구성에 의하여도 좌우되기 때문에 생긴 현상이라고 판단된다. 근류의 비환원당농도는 어느 품종에서도 $R_{6}$ ~ $R_{6.5}$ 까지는 상승 경향을 보인 후 $R_{7}$ 에서 저하하고 있어 환원당에서와 같은 추론이 가능하다.

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Comparison of OECD Nitrogen Balances of Korea and Japan

  • Kim, Seok-Cheol;Park, Yang-Ho;Lee, Yeon;Kim, Pil-Joo
    • 한국환경농학회지
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    • 제24권3호
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    • pp.295-302
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    • 2005
  • The nitrogen (N) balance in Korea during 1985-1997 was calculated according to the surface balance method of the PARCOM guidelines and compared with Japanese N balance. The some differences were founded in the coefficients used on calculating N balance in two nations. Of the important parameters, which can make a big difference in balance, N input by organic fertilizers was not included in Korea different with Japanese, due to absence of reliable statistics and then made lower the input. Nitrogen destruction rate from livestock manure was adjusted differently with 15% in Korea but 28% in Japan. There was some difference in the conversion factors of livestock number into manure N quantity in two nations, but the gap was ignoble scale except beef cattle. Our manure N production rate of beef cattle might be evaluated to be so lower than Japanese. Biological N fixation by pulses was very higher in Korea than in Japan but scarcely affect the increase of total N input, due to small cultivation area. In contrast, N fixation rate by free-living organisms in Korean and Japanese wet paddies showed the big difference with 7.6 and $37.0kg\;ha^{-1}\;yr^{-1}$, respectively, and therefore $29.4kg\;ha^{-1}\;yr^{-1}$ of nitrogen was estimated to be more inputted in Japan. Although there are many points to be more specified and improved, still, Korean N balance was very high with $250-257kg\;ha^{-1}$ in the mid of 1990s, which was the second highest level in OECD countries and furthermore increased continuously during the investigation. In contrast in Japan, which has similar fanning system with Korea, N balance was lower with $130-158kg\;ha^{-1}$ and has decreased continuously since 1993. This high N balance was mainly due to a high usage of chemical fertilizers in our intensive fanning system and the fast increment of livestock feeding. Therefore, the more active action to decrease chemical fertilizer utilization and reduce livestock feeding density is required in the government and farmer sides.

Stable C and N Isotopes: A Tool to Interpret Interacting Environmental Stresses on Soil and Plant

  • Yun, Seok-In;Ro, Hee-Myong
    • Journal of Applied Biological Chemistry
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    • 제51권6호
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    • pp.262-271
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    • 2008
  • Natural abundances of stable isotopes of nitrogen and carbon (${\delta}^{15}N$ and ${\delta}^{13}C$) are being widely used to study N and C cycle processes in plant and soil systems. Variations in ${\delta}^{15}N$ of the soil and the plant reflect the potentially variable isotope signature of the external N sources and the isotope fractionation during the N cycle process. $N_2$ fixation and N fertilizer supply the nitrogen, whose ${\delta}^{15}N$ is close to 0%o, whereas the compost as. an organic input generally provides the nitrogen enriched in $^{15}N$ compared to the atmospheric $N_2$. The isotope fractionation during the N cycle process decreases the ${\delta}^{15}N$ of the substrate and increases the ${\delta}^{15}N$ of the product. N transformations such as N mineralization, nitrification, denitrification, assimilation, and the $NH_3$ volatilization have a specific isotope fractionation factor (${\alpha}$) for each N process. Variation in the ${\delta}^{13}C$ of plants reflects the photosynthetic type of plant, which affects the isotope fractionation during photosynthesis. The ${\delta}^{13}C$ of C3 plant is significantly lower than, whereas the ${\delta}^{13}C$ of C4 plant is similar to that of the atmospheric $CO_2$. Variation in the isotope fractionation of carbon and nitrogen can be observed under different environmental conditions. The effect of environmental factors on the stomatal conductance and the carboxylation rate affects the carbon isotope fractionation during photosynthesis. Changes in the environmental factors such as temperature and salt concentration affect the nitrogen isotope fractionation during the N cycle processes; however, the mechanism of variation in the nitrogen isotope fractionation has not been studied as much as that in the carbon isotope fractionation. Isotope fractionation factors of carbon and nitrogen could be the integrated factors for interpreting the effects of the environmental factors on plants and soils.

남조류의 이형세포 조절 유전자와 질소량에 따른 유전자 발현의 분석 (Analysis of a Heterocyst-controlling Gene and Its Expression upon Nitrogen Starvation in a Cyanobacterium)

  • 배정진;윤호성
    • 생태와환경
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    • 제38권4호통권114호
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    • pp.510-517
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    • 2005
  • 선형의 남조류 아나베나는 광합성과 질소고정 능이 있으며, 이는 아마도 이 남조류가 각종 육수 환경에 잘 적응하는데 큰 역할을 했다고 볼 수 있다. 작은 patS라는 유전자는 질소 고정세포의 형성을 막으며 결과적으로 질소원이 부족한 환경에서 아나베나의 죽음을 가져온다. 본 연구는 patS 유전자 주변의 DNA 염기 서열을 분석하여 codon 활용도를 알아 본 결과 patS를 제외한 다른 유전자가 존재하지 않음을 밝혔다. patS를 포함하는 세 개의 겹치는 cosmid를 찾아서 기존의 알려진 이형세포 발달 유전자를 탐색하였으나 나타나지 않았다. 질소원의 결핍에 반응하는 patS 유전자의 발현을 Northern blot 분석과 lacZ reporter 유전자 합성 실험을 통하여 각각 전사와 번역의 단계에서 알아보았다. patS 유전자의 발현은 배지로부터 질소원이 제거된 후 12시간 내에 급격히 증가하는 것으로 나타났다.

Long-term Seasonal and Interannual Variability of Epilimnetic Nutrients (N, P), Chlorophyll-a, and Suspended Solids at the Dam Site of Yongdam Reservoir and Empirical Models

  • An, Kwang-Guk
    • 생태와환경
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    • 제44권2호
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    • pp.214-225
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    • 2011
  • The objectives of the study were to evaluate seasonal patterns of epilimnetic water quality, and determine interannual eutrophication patterns at the dam site of Yong-dam Reservoir using long-term data during 2002~2009. Ionic dilutions, based on specific conductivity, occurred in the summer period in response to the intense monsoon rain and inflow, and suspended solid analysis indicated that the reservoir was clear except for the monsoon. Seasonality of nitrogen contents varied depending on the types of nitrogen and responded to ionic dilution; Ammonia-nitrogen ($NH_4$-N) peaked at dry season but nitrate-nitrogen ($NO_3$-N) peaked in the monsoon when the ionic dilution occurred. The maxima of $NO_3$-N seemed to be related with external summer N-loading from the watershed and active nitrogen fixation of bluregreens in the summer. $NO_3$-N was major determinant (>50%) of the total nitrogen pool and relative proportion of $NH_4$-N was minor. Long-term annual $NO_3$-N and TDN showed continuous increasing trends from 2004 to 2009, whereas TP and TDP showed decreasing trends along with chlorophyll-a (CHL) values. Empirical model analysis of log-transformed nutrients and N : P ratios on the CHL showed that the reservoir CHL had a stronger linear function with TP ($R^2$=0.89, p<0.001) than TN ($R^2$=0.35, p=0.120). Overall results suggest that eutrophication progress, based on TP and CHL, is slow down over the study period and this was mainly due to reduced phosphorns, which is considered as primary nutrient by the empirical model.

Nostoc muscorum과 혼합배양한 담배 배양세포의 아미노산 함량 변화 (Changes of Amino Acid Content of Cultured Tobacco Cells by Association Culture with Nostoc muscorum)

  • 정현숙
    • Journal of Plant Biology
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    • 제34권1호
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    • pp.31-35
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    • 1991
  • 질소고정능이 있는 N. muscorum과 담배 배양세포의 혼합배양시 질소원을 제거한 배지에 polyamine을 첨가하여 배양조건을 개선하였다. 그리고, 단백질 조성 아미노산을 조사하여 N. muscorum과 혼합배양하여 담배 배양세포의 아미노산 함량변화를 조사한 결과 총 아미노산 및 메티오닌의 함량이 상당히 증가하는 것으로 나타났다. 특히 $10^{-3}\;M$ spermine을 처리한 배지에 혼합배양한 세포에서 메티오닌 등이 현저하게 증가하였으며, N. muscorum의 질소고정으로 혼합배양한 담배 배양세포의 단백질 조성 아미노산이 상당히 증가되었다.

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