Basal Nitrogen Research Articles

Effect of rice plant growth on denitrification in rhizosphere soil

The effect of rice plant growth on the loss of basal nitrogen (N) through denitrification in the rhizosphere of subsurface soil was investigated by the 15N balance method. Labeled 15N was applied to the deep soil layer to distinguish between the N losses in the surface and subsurface soils. Denitrification in pots with whole plants (Control) was compared with that in pots with plants cut off at the base of the culm (Pcut) to evaluate the effect of plant growth on denitrification. The upward movement of the applied 15N from the deep soil was negligible. Thus, the amount of unrecovered 15N was equal to the amount of N lost through denitrification in the rhizosphere of the subsurface soil (20–150 mm soil depth). In the Control treatment, values of redox potential at 50 and 90 mm soil depths were negative throughout the experimental period. Therefore, it was assumed that the redox potential could not have been the limiting factor for the N loss through denitrification in this experiment. The α-naphthylamine-oxidizing activity of roots decreased drastically after the cutting treatment. The estimated amount of de nitrified 15N in the rhizosphere of the subsurface soil was significantly higher in the Pcut treatment than in the Control one at 30 and 40 d after transplanting (DAT), while it was comparable in the two treatments at 52 and 64 DAT. Since a greater amount of 15N loss was found to occur when there was no absorption of 15N by the plants, the absorption of 15N by plants may have contributed to the suppression of denitrification. The amount of immobilized 15N in the Control treatment was larger than that of the Pcut treatment throughout the experiment. N immobilization might have also contributed to the suppression of denitrification in the rhizosphere of the subsurface soil.

Synthesis, structure and magnetic behavior of a di-μ-chloro-di-μ-imidazolato-tetracopper(II) complex with two dinucleating macrocycles

The synthesis, crystal structure and magnetic behavior of the di-μ-chloro-di-μ-imidazolato-tetracopper(II) complex [L 2Cu 4(Im) 2Cl 2](ClO 4) 4(CH 3OH), where Im is imidazole and L is 3,6,9,17,20,23-hexaazatricyclo[23.3.1.1 11,13]triaconta-1(29),11(30),12,14,25(26),27-hexaene, have been studied. X-ray structure analysis shows that the compound crystallizes in monoclinic and space group P2(1)/ c, with a=13.716(3), b=11.165(2), c=27.340(6) Å, β=98.43(3)° and Z=2. The cation consists of two imidazolate bridged dicopper(II) centers encapsulated within two macrocycles, respectively, which are linked by a pair of chloride atoms. In each imidazolate bridged dicopper(II) center, both copper atoms are five-coordinated by four basal nitrogen atoms (three from the macrocycle and one from the imidazolate) and one axial chloride atom shared with another copper atom in the other imidazolate bridged dicopper(II) center in the molecule. pH-dependent ESR studies of the title complex in frozen 50% aqueous DMSO solution show that the bridged cation [LCu 2(Im)] 3+ exists as a major species in solution over the range 7.00≤pH≤11.5, and the μ-Im bridge is broken in the pH range of 7.00–5.20. The molar conductance of the title complex indicates that the μ-Cl bridge is almost entirely dissociated when dissolved in 1:1 DMSO aqueous solution. However, when Cl − ions were gradually added to the solution, a complex with a CuN 4Cl chromophore was successively formed. Magnetic measurement studies on the powder sample reveal that antiferromagnetic interactions are mediated through both μ-Im ( J 1=−26.78 cm −1) and μ-Cl ( J 2=−9.52 cm −1) bridges.

Influence of Nitrogen Application on Anther Length, Anther Width and Number of Engorged Pollen Grains as Characters Related to Cooling Injury in Rice Plants.

Anther length, anther width, and number of engorged pollens were reported to have a relationship to cooling injury of rice. The effects of nitrogen application on anther size and number of pollens were studied in a field for two years. Higher basal nitrogen application (tested from 0 to 13 g/m2) resulted in shorter anther length, shorter anther width, and fewer engorged pollens. The top dressing of nitrogen (4 g/m2) applied at the panicle formation stage resulted in shorter anther length, shorter anther width, and fewer engorged pollens compared with top dressings at other stages or with no top dressing. The effects of a top dressing on anther size and on the number of pollens were small when the nitrogen applied was 10 g/m2.

The synthesis, structure and SOD-like behaviors of a μ-imidazolato-dicopper(II) complex with a binucleating hexaazamacrocycle

The synthesis, crystal structure and magnetic properties of the imidazolate-bridged dinuclear copper(II) complex [LCu 2(Im)(DMSO) 2](ClO 4) 3(DMSO), where ImH is imidazole, and L is 3, 6, 9, 17, 20, 23-hexaazatricyclo[23.3.1.1 11,13]triaconta-1(29), 11(30), 12, 14, 25(26), 27-hexaene, have been studied. Single crystal X-ray diffraction determination reveals the distorted tetragonal pyramid geometries of the imidazolate bridged dicopper(II) center are incorporated within the binucleating macrocycle. Both copper atoms are five-coordinated by four basal nitrogen atoms (three from the macrocycle and one from the imidazolate) and one oxygen atom from the DMSO molecule. Two coordinated DMSO molecules are situated at the same side of the macrocycle. The Cu–Cu separation in the complex is 5.93 Å. Magnetic measurements and ESR spectroscopy studies exibit an antiferromagnetic exchange interaction with a coupling constant of J= − 26.94 cm −1. Investigations on the pH-dependent ESR of the title compound in frozen 50% aqueous DMSO solution confirm the existence of the bridged cation [LCu 2(Im)] 3+ as a major species in solution mainly in the range 5.2⩽pH⩽11.5. The imidazolate bridge is broken in the pH range of 5.2–3.3, which is close to that for the native enzyme.

NifA-Dependent Expression of Glutamate Dehydrogenase in Rhizobium etli Modifies Nitrogen Partitioning During Symbiosis

Constitutive expression of foreign glutamate dehydrogenase in Rhizobium etli inhibits bean plant nodulation (A. Mendoza, A. Leija, E. Martínez-Romero, G. Hernández, and J. Mora. Mol. Plant-Microbe Interact. 8:584-592, 1995). Here we report that this inhibition is overcome when controlling gdhA expression by NifA, thus delaying the GDH activity onset after nodule establishment. Expression of gdhA modifies the nitrogen partitioning inside the bacteroid, where newly synthesized ammonia is preferentially incorporated into the amino acid pool instead of being exported to the infected cells. As a consequence, the fixed nitrogen transport to the leaves, measured as the ureides content in xylem sap, is significantly reduced. Nitrogenase activity, although not nifHDK expression, is significantly reduced in bacteroids expressing gdhA, probably due to the utilization of energy and reducing power for nitrogen assimilation. Here we show that ammonia assimilation inside R. etli bacteroids is active, albeit at low levels, and when enhanced is deleterious to the symbiotic performance. This leads us to believe that further reduction of the basal nitrogen metabolism in the bacteroid might stimulate the nitrogenase activity and increase the nitrogen supply to the plant.

Effect of Gibberellic Acid Spray and Basal Nitrogen and Phosphorus on Productivity and Fatty Acid Composition of Rapeseed‐Mustard

AbstractTwo field experiments were conducted during] 994‐95 to study the effect of spray of 10−5 M GA3 at 40 days after sowing on mustard (Brassica juncea (L.) Czern & Coss.) cv. Varuna grown with basally applied 0, 40, 80 and 120 kg N ha−1 (Expt. 1) and 0,15, 30 and 45 kg P ha−1 (Expt. 2) on pod number per plant, seeds per pod, 1000 seed weight, seed yield, biological yield, harvest index and fatty acid composition of oil. No significant difference between water and GA3 spray was found when basally applied nitrogen was 0 or 40 kg N ha−1. N80 proved to be the best for yield characteristics. In another experiment on phosphorus, GA3 and 30 kg P ha−1 individually enhanced the yield, but interaction of GA3 and P remained non‐significant. The fatty acid composition of oil in both experiments was significantly affected only by nitrogen and phosphorus treatments for oleic acid and erucic acid. It was found that return in the form of yield was more for every kg applied fertilizer under GA, spray treatment. The response was more for N fertilizer in comparison to P. GA3 at a low level of fertilization significantly increased the return from fertilization.

New macrocyclic dioxotetraamines bearing 2-methylfuran pendant(s): synthesis, properties and crystal structure of the copper(II) complexes

A series of new macrocyclic dioxotetraamine ligands having 2-methylfuran pendent(s), 4-(2-methylfuran)-1,4,7,10-tetraazacyclotridecane-11,13-dione (H 2L 1), 4,7- bis(2-methylfuran)-1,4,7,10-tetraazacyclotri-decane-11,13-dione (H 2L 2), 1-(2-methylfuran)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H 2L 3) and 1,11 bis(2-methylfuran)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H 2L 4), have been synthesized and characterized. The solution behaviours of the copper(II) complexes of the four ligands have been studied with ESR, cyclic voltammetry (CV) and UV-vis techniques. A red-shift has been observed for the maximum absorption band of the electronic spectra of CuL 1, CuL 3 and CuL 2, CuL 4 in comparison to those of the corresponding unsubstituted copper(II) complexes CuL 01 and CuL 02, respectively. Electrochemical studies suggest that the introduction of 2-methylfuran pendant(s) to the macrocyclic dioxotetraamines destabilizes the Cu III ion comparing with the unsubstituted species for both of the two kinds of macrocycles (13-membered and 14-membered macrocycles). The copper(II) complex of (H 2L 2), has been isolated as a single crystal and the crystal structure determined by X-ray diffraction analysis. It is interesting that the complex has an N-meso chiral nitrogen configuration. The Cu II atom is in five coordination environment with four basal nitrogen atoms and one axial oxygen atom from H 2O, and it adopts a distorted square pyramidal configuration.

New 1,4,8,11-tetraazacyclotetradecane-5,7-dione ligands appended with additional 2-methylthiophene(s) pendant: crystal structure and properties of their copper(II) complexes

Two new macrocyclic dioxotetraamine ligands, 1-(2-methylthiophene)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H2L1) and 1,11-bis(2-methylthiophene)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H2L2), have been synthesized and characterized. The resulting dioxocyclams readily coordinate to CuII. The CuII complex of H2L2 has been isolated as a single crystal and the structure determined by X-ray diffraction analysis. The copper atom is in a square-planar environment with four basal nitrogen atoms. The solution behaviour of the CuII complexes, CuL1 and CuL2, has been further studied by e.s.r., u.v.–vis. and cyclic voltammetric techniques. A remarkable redshift has been observed for the maximum absorption band in the electronic spectra of CuL1 or CuL2 compared with that of the unsubstituted copper species (CuL). Electrochemical studies suggest that the introduction of thiophene pendant(s) to the macrocycle destabilizes the CuIII ion compared with the unsubstituted dioxocyclam, and the reason for this is discussed.

A Single Basal Application of Controlled-Release Coated Urea to Rice Cultures Using Pot Seedlings in a Cool Region.

A low-cost, high yielding culture of rice was studied by the application of controlled-release coated urea (CU) to pot seedlings (PS) -raised in a pot culture nursery box- cultivated in a cool region, and compared to the application of conventional fertilizer (CF) to pot seedling (PS) and mat seedlings (MS) -raised in a broadcast secding nursery box. The plant length and the number of tillers per hill in the PS plots were longer and larger than those in the MS plots due to the superior characteristics of the seedlings. However, the number of tillers/m2 in the PS plots was less than that in the MS plots. Reflecting the nitrogen released from the coated urea, the plant length and number of tillers/m2 in the PS-CU plots were inferior to those in the PS-CF and MS-CF plots at the early growth stage. However, after the neck node differentiation stage, these were reversed due to the increased release of nitrogen from the coated urea. As a result, the leaf color value and dry weight of the rice in the PS-CU plots were higher than those in the PS-CF and MS-CF plots. The yields of brown were in the following order : PS-CU plot > PS-CF plot > MS-CF plot. The number of panicles and spikelets were larger in the PS-CU plot than those in the PS-CF and MS-CF plots, which might affect the increased yield. It seems that the photosynthetic activity of the rice plants in the PS-CU plot was maintained at a high rate throughout the ripening stage. The nitrogen uptake and efficiency of the applied fertilizer were in following order:PS-CU plot > PS-CF plot > MS-CF plot. The recovery of basal nitrogen in coated urea (63∼68%) was much greater than that of ammonium sulfate (30∼40%), and greater than the recovery of the top dressed nitrogen of ammonium sulfate (41∼59%).

Synthesis, crystal structure and properties of the nickel(II) complex of a new dioxocyclam bearing 2-methylfuran pendants

A new dioxocyclam ligand, bearing two 2-methylfuran pendants, has been synthesized and its nickel(II) complex isolated as a single crystal. The crystal structure of the complex has been determined by X-ray diffraction analysis. The complex adopts an unusual cis-configuration. The square-planar N4 coordination of the four basal nitrogen atoms with Ni II is evident, with the dioxocyclam moiety composed of two tertiary amine Ns and two deprotonated amide N; s; the latter nitrogens have stronger coordination bonds than those in the tertiary amines. There is a hydrogen bond between O(1) and a water molecule [O(1) H2O = 2.698]. The solution behaviour of NiL (1) has been further studied by u.v.-vis. and cyclic voltammetric techniques. A remarkable red-shift was observed for the maxima absorption band of the electronic spectra of NiL (1) in comparison to that of NiL 0 (H2L0, dioxocyclam = 1,4,8,11-tetraazacyclo-tetradecane-5,7-dione).

Response of Mustard to Ethrel Spray and Basal and Foliar Application of Nitrogen

AbstractIn a field trial conducted during 1992–93 and 1993–94, the effect of basal (B) nitrogen (N) (45 and 60 kg N ha−1) and foliar application (F) of water (W) or 10 kg N ha−1 and 400 or 600 ppm ethrel (E) (2‐Chloro ethyl phosphonic acid) at 70 days after sowing was studied on leaf area index and dry mass at 90 days and pod number per plant, seeds per pod, 1000 seed weight, seed yield, oil content and oil vield at harvest of mustard (Brassica juncea L. Czern & Coss.) cv. T‐59. Recommended basal (B) application of 90 kg N ha (BN90) was used as control. On the basis of 2 year data it was found that basal application of 60 kg N and foliar spray of 10 kg N ha −1 and 600 ppm ethrel gave higher values for growth and yield characteristics and enhanced seed yield and oil yield by 12.5 and 14.8%, respectively over control BN90.

Combinations of ruminally degradable and escape protein for implanted finishing steers (1995)

One hundred forty-four crossbred medium framed steers (738 lb) were used to compare urea and soybean meal as basal supplemental nitrogen sources and sources of high (blood meal:corn gluten meal; BMCG) or low (soybean meal; SBM) ruminal escape proteins as additional protein supplementation. Basal diets were formulated to contain 1 0.8% crude protein (CP) and were supplemented with either urea or SBM (.91% and 5.55% of DM, respectively). An additional 2 percentage units of CP were either provided or not provided as SBM or as a 50:50 combination (protein basis) of BMCG. Steers were implanted with Revalor-S® and fed experimental diets for 113 days. Steers fed urea diets consumed 3.9% more feed than those fed SBM as the basal N source. Average daily gain was unaffected by treatment. Soybean meal improved feed efficiency 3.8% compared to urea as a basal nitrogen source. Supplying additional CP from SBM increased feed efficiency 4.4% compared to BMCG. Hot carcass weight and dressing percentage were not affected by treatment. Supplementing basal diets with 2 percentage units of CP increased percentage of carcasses grading choice, KPH fat, and yield grade. High dry matter intakes resulted in metabolizable protein intakes above the predicted requirements (760 g/d) for steers in this experiment, which may have precluded a response to supplemental protein.

Response of mustard to seed treatment with pyridioxine and basal and foliar application of nitrogen and phosphorus

Abstract In a simple randomised field trial conducted during 1985–86/ 1986–87, the effect of basal nitrogen (45 and 60 kg N/ha) and basal phosphorus (15 and 20 kg P/ha) applications together with the soaking of seeds in 0.025% aqueous pyridoxine hydrochloride solution for 4h and foliar applications of 15 kg N/ha and 5 kg P/ha in two installments at 70 and 90 days after sowing (DAS) was studied on the performance of mustard (Brassica juncea L.). Recommended basal applications of 90 kg N/ha and 30 kg P/ha (BN90P30) was used as the control. The parameters studied included leaf area index (LAI) at 60, 80, and 100 DAS, net assimilation rate at 60–80 and 80–100 day intervals, and pods/plant, seeds/pod, seed yield, oil content, and oil yield at harvest. In general, the pyridoxine treatment proved superior over water soaking. The higher basal fertilizer dose was effective and foliar application of N and P gave higher values as compared to the water foliar application alone. The combination of pyridoxine + BN60P20...

Synthesis, crystal structure and properties of a five-coordinate copper(II) complex

The five-coordinate copper(II) complex [(3,3′-trimethylenedinitrilo)bis(2-butanone oximato)]copper(II) bromide (CuHLBr) has been prepared and its crystal structure has been determined. The complex has a square-pyramidal structure with the copper displaced 0.43 Å out of the basal nitrogen plane. The CuBr distance is 2.955 Å. The differences in the structures of the copper(II) and copper(I) complexes is discussed. Covalency of the coordinate bond for the title complex is also discussed based on ESR spectra.

A note on the influence of oestradiol-17β implants on serum hormone and metabolite concentrations in response to an epinephrine challenge in lambs

Eight wether lambs were used to determine effects of an oestradiol-17β (E2β) implant on metabolic responses to an epinephrine challenge. Blood was sampled before and after an epinephrine challenge, on days 0 and 22 of E2p implantation.Oestradiol-17 ft implants increased pre-injection (basal) serum insulin (INS), growth hormone and free fatty acids (FFA), and decreased basal serum urea nitrogen. After 21 days of E2Pimplantation, total concentrations of FFA decreased and INS increased in response to the epinephrine challenge compared with pre-implantation values. It is concluded that E2/3 implants alter metabolic responses to an epinephrine challenge in wether lambs.

Patterns of Soil Nitrogen Release in Paddy Fields of Warm Regions in Japan and Diagnosis of Fertilizer Application. I. Influence of soil nitrogen release from paddy soils on growth and yield of rice plants of warm regions.

地域や肥沃度が異なる水田で, 地力窒素の発現が暖地水稲の生育や収量に及ぼす影響と水田土壌の地力窒素レベルに応じた適正な施肥量について検討した. まず, 速度論的方法を適用し, 水稲生育期間中の地力窒素発現量の推定を行った結果, 地域間で著しく異なり, また同じ地域内でも地力増強程度の違いにより10a当たり5kg前後も異なった. 窒素無施用区の水稲窒素吸収量を水稲による地力窒素吸収量の指標として, 地力窒素発現量の推定値と比較すると, 発現量に対する吸収量の割合はほぼ7～8割であった. 基準量を施肥した条件下で, 地力窒素吸収量と水稲ニシホマレの収量との関係についてみると, ニシホマレの収量は地力窒素の吸収量が10a当たり8kgまでは, 地力窒素量に応じて高くなる傾向にある. しかし, さらに多くなリ9kg近くになると収量は頭打ちとなり, 稲体中の窒素量は増えるが, 玄米生産に結びつかず, 過剰分に相当する窒素の吸収はむだであることから, 施肥量を減肥してよいと判断された. 良食味品種ヒノヒカりは地力窒素の影響を受けやすく, 施肥区の収量は地力窒素吸収量が10a当たリ8kg近くで頭打ちとなるのがみられた. また, 地力窒素吸収量と基肥量との関係についてみると, 地力窒素吸収量が少ない水田では基肥量として10a当たリ6kg程度が必要であるが, 地力窒素量が7～8kgの圃場では4.5kg程度が適量であり, 8kg以上ではさらに減肥が必要であった.

Countermeasures of Decreased Yield by Continuously Cropped Soybeans. 9. Managemant practices of a soiling barley for yield increase of soybeans and effect of basal nitrogen fertilizer applied on soybeans in the field of plowed a soiling barley in

Countermeasures of Decreased Yield by Continuously Cropped Soybeans. 9. Managemant practices of a soiling barley for yield increase of soybeans and effect of basal nitrogen fertilizer applied on soybeans in the field of plowed a soiling barley in

Varietal Difference in Leaf Senescence during Ripening Period of Advanced Indica Rice.

The study has been carried out to evaluate varietal difference in leaf senescence during the ripening period in relation to sink size and nitrogen application. Leaf senescence was early in the medium-duration lines. Among the short-duration types, there were both early and late aging lines. The medium-duration lines had larger leaf area and higher sink sizes at the anthesis than short-duration types. The pattern of leaf area reduction during the ripening period in the short duration line, with relatively higher sink size, was almost similar with that in the medium-duration lines. However, in the short-duration lines with relatively small sink size, no significant leaf area reduction was observed until two weeks after the anthesis, and then the leaf area began to decrease rapidly in these lines. Decrease in leaf area during the ripening period varied with the rate of basal nitrogen (N). Higher basal N increased the rate of leaf area reduction by increasing the sink size. On the other hand, N-topdressing at the anthesis decreased the rate of leaf area reduction during the ripening period. Likewise, the reduction in sink size as imposed by removal of spikelets decreased the rate of leaf area reduction during the ripening period. Significant correlation coefficients between the sink size and the amount of N remobilized from leaves to panicles, and between the decrease in leaf area and the amount of N remobilized from leaves to panicles were observed. Therefore, the decrease in the leaf area during the ripening period is mainly governed by the amount of N remobilized from leaves to panicles, which is affected by the N requirement of grains for ripening and the amount of N absorbed during this period.

Effect of Basal Nitrogen Fertilizer on Occurrence of 'Goma-sho' in Chinese Cabbage

Effect of Basal Nitrogen Fertilizer on Occurrence of 'Goma-sho' in Chinese Cabbage

The effect of clenbuterol on basal protein turnover and endogenous nitrogen loss of sheep.

Seven measurements of the effect of clenbuterol on basal nitrogen excretion (UNE), and protein turnover were made in six female sheep. The sheep were sustained by the intraruminal infusion of energy as volatile fatty acids to provide maintenance, but given no protein (N-free) for 12 d (6 d control, 6 d clenbuterol). Clenbuterol reduced UNE by 20%, but only on day 2 of the 6 d subperiod. Protein flux (equivalent to degradation on N-free nutrition), measured on day 6 by the irreversible loss of leucine was significantly increased (12%) by clenbuterol. Amino-N oxidation measured by N excretion was unchanged and, therefore, protein synthesis was also increased. During the 12 d N-free period, the recovery of urinary total N (Kjeldahl) as the sum of urea, ammonia, creatinine and purine derivatives, declined from 87.7 to 74.2%. The form of this missing N was not identified. The effect of clenbuterol of increasing both degradation and synthesis is unlike that reported in the literature for animals receiving protein when, in general, synthesis is unchanged and degradation reduced. This could be due to a different effect of clenbuterol in the N-free state, or to unchanged effects on protein pools other than muscle whose relative contribution to protein metabolism is different in the N-free state.