• 한국식물학회:학술대회논문집
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• 한국식물학회 1996년도 식물학심포지움 식물호르몬과 신호전달
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• pp.50-63
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• 1996

Nitrogen (N) is an important regulator of the expression of genes involved in carbon and N assimilation pathways in plants by selectively altering the levels of proteins and/or mRNAs. These in C4 plants include genes for such as phosphoenolpyruvate carboxylase, carbonic anhydrase, and pyruvate-Pi dikinase. The C4 genes are regulated in mesophyll cells by N availability both transcriptionally and posttranscriptionally through cytokinins and glutamine as signals. The level of both the signals is up-regulated by N availability: cytokinins in roots and glutamine in leaves. The level of glutamine is controlled by the differential expression by N of glutamine synthetase and ferrdoxin-dependent glutamate synthase genes which locate in the mesophyll cells of C4 plants. The results is discussed as molecular mechanism for the greater N use efficiency of the plants as well as N partitioning is the photosynthetic cells.

• 한국초지조사료학회지
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• 제15권4호
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• pp.238-244
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• 1995

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape(Brassica napus L.) was sown on Sep. 1, 1994. Experimental plots were divided into three replicates under 6 different cutting dates(l0 days interval from Oct. 15 to Dec. 4). Field-grown palnts were sampled on the each cutting date and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, dry matter yields were 152, 274, 500, 718, 776 and 981 kg/lOa, respectively, from the cutting date on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. Cmde protein yield significantly increased as cutting date was later until Nov. 14, thereafter a significant increase did not occured. Nitrogen and starch contents per plant significnatly increased as the cutting date was later. The increasing rate of starch was greatly higher than that of nitrogen. On the wintering period, nitrogen reserves in mts were 85.3, 68.8, 47.6, 28.3, 44.3, and 55.3 mglplant, and starch reserve were 11 1.3, 75.3, 39.3, 19.6, 26.4 and 34.6 mglplant, respectively, in the plots cut on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. It showed that carbohydrate reserves were much highly utilized than nitrogen reserves during wintering period. The rates of winter survival were 91, 83, 46, 22, 35 and 43% and regrowth yields were 692, 545, 316, 84, 127 and 140 kgD.M/lOa, respectively, in each plots. The highly significant correlation (p<0.01) between the level of organic reserves and the rate of winter survival or regrowth yield were obtained.

• 한국어류학회지
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• 제34권2호
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• pp.102-112
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• 2022

본 연구는 위내용물 분석과 안정동위원소(δ¹³C and δ¹⁵N) 분석을 통하여 우리나라 동해 북부 연안에 출현하는 명태(Gadus chalcogrammus)와 대구(G. macrocephalus)의 종내 및 종간 먹이자원 분할을 조사하였다. 두 종은 중층성 육식성 어종으로 명태는 저서성 및 중층성 갑각류를 주로 섭식하였고, 대구는 어류를 주로 섭식하였다. 위내용물 분석 결과에 대한 Non-metric multidimensional scaling (nMDS) ordination과 permutational multivariate analysis of variance (PERMANOVA)은 두 종의 종내 및 종간 먹이조성의 차이와 먹이자원 분할을 보여줬다. 안정동위원소 분석 결과 δ¹⁵N 값은 종간 유사하였지만, δ¹³C 값은 대구가 높은 값을 나타내어 두 종간 생태지위 차이를 보여줬다. 명태는 체장 증가에 따라 큰 체장군에서 새우류와 두족류를 더 많이 섭식하는 먹이 전환을 나타냈지만, 대구는 체장군 간 먹이조성이 유사하였다. 안정동위원소 분석에서도 체장군 간 차이를 보였는데, 두 종의 큰 체장군은 작은 체장군에 비해 더 높은 δ¹⁵N 값을 나타낸다. 결론적으로 본 연구는 명태와 대구의 위내용물 분석과 안정동위원소 분석을 통하여 종내 및 종간 먹이 차이와 생태지위 분할의 증거를 보여줬다.

• 한국초지조사료학회지
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• 제16권1호
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• pp.1-8
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• 1996

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape (Brussicu napus L.) was sown at 10 day> interval from Sep. I to Nov. 1. Field-grown palnts were sampled on the before wintering (Dec. 4) and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, the dry matter yields from the plots sown on Sep. 1, Sep.11 and Sep. 21 were 860, 596 and 260 kg/lOa, respectively. No. harvest was canied out on the plots sown after Oct. 1 because the growth state was not enough to cut. Both of nitrogen and starch contents per plant significantly increased as the seeding date was later. On the wintering period, the contents of nitrogen reserves in roots were 176.8. 120.1, 71.7, 84.0, 72.1, 45.3 and 33.3 mg/plant, those of starch reserves were 199.0. 55.8, 21.8, 92.6, 86.5, 36.4 and 29.0 mglplant, resepctively, in the plots sown on Sep. 1, Sep. 11, Sep. 21, Oct. I, Oct. 11, Oct. 21 and Nov. 1. The rates of winter survival were 40, 36, 33, 85, 87, 59 and 49% and regrowth yields were 161, 86, 65, 520, 451, 121 and 33 kgD.M/lOa, respectively, in each plots. 'Ihese results clearly showed that seeding date has a close influence on the level of organic reserves and forage yield, and that the possibility of continuous utilization on the before and alter wintering is extremely limited by seeding date.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1443-1450
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• 2003

Crossbred (Bos taurus${\times}$Bos indicus) calves were used from birth till 14 weeks of age to evaluate three sources of protein that differed in ruminal degradability viz. groundnut cake alone (HD) or in combination with cottonseed meal (MD) and meat and bone meal (LD), when fed along with two sources of non-structural carbohydrates viz. raw (R) and thermally processed (P) maize. Twenty four new born calves were arranged in six groups in a $3{\times}2$ factorial design and fed on whole milk up to 56 d of age. All the different calves received calf startes along with green oats (Avena sativa) from 14 d of age onwards free-choice. A metabolism trial of 6d starters duration, conducted after 90 d of experimental feeding, revealed greater (p<0.05) digestibility of DM, OM, total carbohydrates, NDF and ADF in calves fed on the P diets than on the R diets promoting greater (p<0.05) metabolizable energy intake. The digestibility of NDF was higher (p<0.01) on LD diets where as calves on MD diets exhibited significantly lower digestibility of ADF (p<0.01). The retention of nitrogen per unit metabolic body size was significantly (p<0.05) higher on the LD-P diet than on the diet HD-P which, in turn, was higher (p<0.05) than that of HD-R. Nitrogen retention as percentage of intake was significantly greater (p<0.05) on LD-P than on LD-R diets (52.2 vs. 36.4%). Also, P fed calves utilized nitrogen more efficiently than the R fed as shown by retention of significantly greater proportions of intake (47.4 vs. 40.9%) and absorbed (65.8 vs. 59.5%) nitrogen. Calorimetric evaluation of the diets through open-circuit respiration chamber revealed that the dietary treatments had no impact on methane production by calves. The intake of DE and ME was improved (p<0.01) because of maize processing resulting in greater (p<0.01) retention of energy. The protein degradability exerted no influence on the partitioning or retention of energy. A significant interaction between cereal and protein types was evident with respect to retention of both nitrogen (p<0.01) and energy (p<0.05). In conclusion, no discernible trend in the influence of cereal processing was apparent on the dietary protein degradability, but the positive effect of cereal processing on energy retention diminished with the increase in dietary undegradability.

• 한국작물학회지
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• 제44권1호
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• pp.11-19
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• 1999

This experiment was conducted with nine wheat geno-types to choose the wheat which has excellent early vigour. 'Vigour 18' and 'ZL 59A' are excellent in the long coleoptile genotype, while 'Amery' and 'Janz' are excellent in the short coleoptile genotype. Responding to the growth stage and nitrogen level, Vigour 18 is predominant in the long coleoptile genogype, while Janz in the short coleoptile genotype. Responding to sowing density and nitrogen level, the higher the sowing density was, the shorter the leaf area of Vigour 18 and Janz. Also the leaf area turned out to larger in the plot fertilized with high nitrogen than in the plot fertilized with low nitrogen. This is true of leaf weight and root weight. Concerning specific leaf area (SLA) and leaf area ratio (LAR), the higher the sowing density was, the SLA tended to grow larger, while the SLA grew larger in the plot fertilized with low nitrogen, as were found in Vigour 18 and Janz. The roots of long coleoptile genotype, Vigour 18, turned out to grow longest on the plot sown with 3 seeds. While the roots of short coleoptile genotype, Janz, grew longest on the plot sown with 2 seeds. The relative growth rate (RGR) was the same at low N rates and high N rates. The RGR was 0.071 and 0.072 g $g^{-1}d^{-1}$ at low N rates and high N rates. The partitioning of RGR into net assimilation rate (NAR) and LAR showed that the average LAR at low N rates was similar to the LAR at high N rates. Variation within each cultivar in the LAR and NAR was small relative to the difference between them at low N rates and high N rates. Above ground mass was 8.2 mg greater at high N rates than low N rates, whereas leaf area was 0.05 $\textrm{m}^2$$kg^{-l}$ greater at high N rates than low N rates. The NAR was similar at low N rates and high N rates, whereas LAR was greater at high N rates (0.05 $\textrm{m}^2$$kg^{-l}$); variation in SLA was responsible for the variation in NAR and LAR both at low N rates and high N rates. NAR was more closely associated with the reciprocal of SLA.

• 대한화학회지
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• 제28권4호
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• pp.244-250
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• 1984

산${\cdot}$염기용매분배법과 규소산 칼럼 크로마토그라피법 및 용융 실리카모세관 칼럼크로마토그라피, 질량분석법을 사용하며 셀룰로오스와 리그닌의 열분해생성물중의 여러고리 방향족 화합물의 분리와 동정을 수행하였다. 16가지의 여러고리 방향족 화합물이 머무른 계수와 질량스펙트럼데이타에 의해서 확인되었다. 두가지 물질 모두에서 같은 종류의 여러고리 방향족 화합물이 생성되었으며, 그 함량에 있어서는 리그닌에서 훨씬 많은량이 생성되었다. 극히 발암성인 질소 및 유황을 함유하는 헤테로 고리 방향족 화합물은 거의 생성되지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1415-1421
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• 2006

Proper nutritional management during the dry period is required to prevent metabolic disorders during the time of parturition and for potential increase milk yield during early lactation, especially under the heat of summer. The effect of prepartum diets on partitioning of nitrogen (N), calcium (Ca), phosphorus (P), magnesium (Mg) and potassium (K) during dry period and early lactation in summer was investigated. Nine cows were assigned to two groups and fed either control (group C: four cows) or high concentrate (group H: five cows) diets to meet 110% of their requirements before parturition. The proportion of concentrate in control diet was 35%, and that in the high concentrate diet was 45%. After parturition, all cows were fed the same diets ad libitum during lactation. Balance trials were conducted at 9, 8 and 7 days before parturition and at 12, 13 and 14 days after parturition. Before parturition, dry matter intake (DMI), DM and NFE digestibility in group C tended to be lower than those in group H. The retention of N (p<0.01) and P (p<0.05) in group C during the dry period was significantly lower than those in group H. The retention of Mg in group C during the dry period tended to be lower than in group H. The concentration of plasma NEFA in group C tended to be higher than in group H during dry period. The prepartum diet did not have an apparent effect on DMI and milk yield at 2 weeks after parturition and N, Ca, P, Mg and K balance after parturition.

• 한국자원식물학회지
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• 제11권2호
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• pp.119-123
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• 1998

Effects of elevated CO2 and temperature on nitrogen (N) uptake , leaf N concentration, N partitioning , N use efficiency (NUE) and grain yield of pot and field grown rice (Oryza sativa. L.cv. Chukwangbyeo) under canopy-like conditions were studied over three years. Rice plants were grown in pots and in the field in temperature gradient chambers containing either ambient(350ppm) or elevated CO2 concentrations (690 or 650ppm) in conbination with either four or seven temperature regimes ranging form ambient temperature(AT) to AT plus 3$^{\circ}C$. There were three N supplies 94g or 6g m-2 to 20g or 48g m-2.Elevated CO2 increased N uptake in field-grown rice ; the magnitude of this effect was thelargest (+15%) at the highest N level. However, in pot-grown rice, N uptake was suppressed with the effect was the largest at high N levels. Leaf N concentration declined at elevated CO2 mainly due to a decrease in N partitiioning to the leaf blades. Air temperature had little effect on the N parameters mentioned previously, wherease NUE for spikelet production declined rapidly with increased temperature irrespective of CO2 concentration. The response of the biomass to elevated CO2 varied with N level, with the greatest response at 20g N m-2 (+30%) . At AT, where high temperature-induced sterility was generally not observed, elevated CO2 increased yield. However, the magnitude of this effect varied greatly (2-39%) with N level, and was mainly dependent on the magnitude of the increase in spikelet number.

• 한국작물학회지
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• 제52권1호
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• pp.104-111
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• 2007

백미의 단백질 함량은 쌀의 품질과 식미을 결정하는 중요한 요인이며, 질소시비에 의해서 크게 좌우된다. 따라서 본 실험에서는 기비 및 분얼비 시용량을 달리하여 수비 시기인 유수분화기에 벼의 생육 및 질소영양 상태를 다양하게 조성한 상태에서 수비 시용량을 달리하였을 때의 백미 단백질함량의 변화를 검토함으로써 고품질 쌀 생산에 맞는 질소 시비체계 설정을 위한 기초 자료를 얻고자 하였다. 1. 백미의 단백질함량은 $6{\sim}9%$로서 기비+분얼비 및 수비 시용량비 증가할수록 높아지는 경향이었는데, 기비+분얼비 시용량이 20 kgN/10a까지 증가하더라도 수비 1.8 kgN/10a 이하일 경우 백미의 단백질함량은 7% 이하였으며. 기비+분얼비 보다는 수비에 의한 단백질 함량 증가폭이 더 컸다. 2. 수확기 지상부 질소함량과 백미의 질소함량간에는 고도로 유의한 직선회귀 관계를 보였는데, 수확기 총 질소흡수량 중에서 58.3%와 46.5%가 각각 이삭과 백미로 전이되었고, 연차간에 큰 차이가 없었다. 3. 백미의 단백질 함량은 유수형성기 지상부 질소 집적량 증가에 따라서는 직선적으로 증가하였고, 유수분화기 이후 수확기까지의 질소 집적량 증가에 따라서는 2차곡선적으로 증가하였으며, 후자의 영향이 컸다. 유수분화기 지상부 질소 집적량이 8 kgN/10a까지 증가하더라도 수비 이후의 질소집적량이 3 kgN/10a미만일 경우에는 백미의 단백질함량이 7% 미만이었다. 4. 수확기까지 총 질소 집적량이 같더라도 단위면적 당 영화수에 영향이 큰 유수분화기까지의 질소 집적량이 차지하는 비중이 클수록 그리고 등숙기 기상환경이 좋아 sink의 충진에 유리한 해에 백미의 단백질함량이 낮아지는 경향이었다.