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1.
Studies of the amino acids distribution in plants subjected to nutrient regimes are limited. The present study investigated the effect of NO3‐N and FeSO4‐Fe regimes on chlorophyll and total amino acids composition of tomato and wheat plants. Also the distribution of 17 amino acids between the different plant parts was studied. Increasing the NO3‐N level up to 200 mg kg‐1 greatly increased the total amino acids content of tomato plants. The total amino acids content of wheat plants continued to increase with addition of NO3‐N up to 400 mg kg‐1. The response of chlorophyll content to NO3‐N supply was highly dependent on Fe level both in tomato and wheat plants. The interaction between NO3‐N and FeSO4‐Fe had a great effect on the total amino acids content and distribution. Iron increased the translocation of proline from roots to leaves. The overall amino acids contents of leaves was higher than that of stems or roots.  相似文献   

2.
Nitrogen nutrition has great influences not only on the growth, but also on leaf quality of tobacco. There have been many reports on the nitrogen nutrition of tobacco, in which various nitrogen constituents such as amino acids and related compounds have been analyzed. But definite conclusions were often hard to be drawn out, since sometimes the work was limited by the failure of finding suitable chemical techniques. The recent development of paper chromatographic methods, however, has made possible to detect the individual amino acids, and has provided a new approach to the study of nitrogen nutrition of tobacco. Using the paper chromatographic techniques, the effects of nitrogen form, the effect of sulfur nutrition and excess of chlorine on free amino acid composition of tobacco leaf have been reported by the authors (1). The next step of the work presented here was undertaken for the quantitative study of the effect of nitrogen nutrition on free amino acid content of tobacco cultured for commercial purpose employing the amino acids estimation method developed by MOORE and STEIN (2) (3).  相似文献   

3.
植物对氨基酸态氮吸收和利用的研究进展   总被引:3,自引:1,他引:2  
传统的观点一直认为植物只能吸收无机态氮,不能直接吸收有机态氮,有机态氮必须分解为无机态氮后,植物才能吸收.然而,近年来越来越多的研究表明植物可以直接吸收有机态氮,特别是氨基酸态氮.重点围绕植物如何吸收和利用氨基酸态氮的过程与机理,综述了植物对氨基酸态氮吸收和利用的研究进展,并提出了进一步研究的方向.  相似文献   

4.
Five‐week‐old tomato plants were transplanted into pots containing 10 kg of potting compost which was amended with 0, 0.1, or 0.3 g of nitrapyrin and 4 g of N from KNO3, (NH4)2SO4 or sewage sludge and were grown in a greenhouse. After 2 to 3 weeks, leaves of the plants grown on any nitrapyrin x N source combination were curled with reduced laminae. Symptoms were most severe with the nitrapyrin x sludge regimes and least severe with the nitrapyrin x KNO3 treatments. With (NH4)2SO4 and sludge, growth was depressed linearly by nitrapyrin additions but was unaffected with KNO3 fertilization. The concentrations of Ca and Mg in the shoots were lowered linearly or curvilinearly by nitrapyrin combination with any fertilizer whereas that of K was unaffected. Levels of Mn in leaves rose with nitrapyrin additions to the (NH4)2SO4 or sludge treatment but were stable with any of the nitrapyrin x KNO3 combinations. Cation antagonism among NH4 +, Ca++, and Mg++ is suggested as affecting the concentrations of these ions in tissues, whereas acidification of the medium and a restriction in dry matter production may account for the elevated levels of Mn in the tomato shoots grown in the presence of nitrapyrin.  相似文献   

5.
农民传统过量肥水供应可能导致土壤氮素和盐分积累,滴灌施肥能在根区精确供应肥水以满足作物需求。为明确膜下滴灌日光温室黄瓜-番茄轮作体系氮素供应对土壤氮残留、电导率及作物产量和根干质量的影响,该研究设计空白(NN)、有机肥对照(MN)、优化供氮(RN)、高量供氮(HN)、传统供氮(CN)5个处理,进行了2008-2010年6季田间试验。结果表明,随着氮素供应量的增加,根层土壤硝态氮和电导率显著增加,CN处理加快并加剧了土壤硝态氮和盐分积累。3个黄瓜-番茄轮作周期,氮素供应RN、HN、CN处理的土壤硝态氮平均分别为176.9、346.6、500.8 kg/hm2,CN处理是RN处理的2.83倍(P0.05)。3a黄瓜季RN、HN、CN处理的土壤硝态氮积累量平均分别为-1.87、-49.61、-3.52 kg/hm2、番茄季分别为74.89、225.23、343.15 kg/hm2,CN处理积累量是RN处理的4.58倍(P0.05)。3个轮作周期后,RN、HN、CN处理比试验前的土壤硝态氮残留增加了219.1、526.9、1 018.9 kg/hm2,平均每个轮作周期增加73.0、175.6、339.6 kg/hm2,CN处理是RN处理的4.65倍(P0.05)。3个轮作季后,NN、MN、RN、HN、CN处理土壤电导率分别为433.8、681.5、824.5、927.5、1 120.0μS/cm,RN、HN、CN处理显著高于MN、NN处理(P0.05)。2008年番茄季、2009黄瓜季、2009番茄季、2010番茄季拉秧后的土壤电导率差异显著,CN处理是RN处理的1.15、1.29、1.40、1.36倍(P0.05),表明RN处理可显著降低土壤次生盐渍化的风险。每个轮作周期的土壤硝态氮、电导率动态变化均存在2个积累时期,分别在7月初-8月初的夏季休闲和9月初-11月中旬的番茄结果期。总之,优化供氮比传统供氮减施氮肥66.7%,显著降低土壤硝态氮残留和土壤电导率,保证黄瓜番茄产量不减,将为日光温室黄瓜番茄轮作体系滴灌施肥制度提供科学依据。  相似文献   

6.
袁伟  董元华  王辉 《土壤》2010,42(4):664-668
在水培条件下,设计了7种试验处理其N源分别为NO3--N、NO3--N+谷氨酸态氮、NO3--N+苯丙氨酸态氮、NO3--N+谷氨酸态氮+苯丙氨酸态氮、谷氨酸态氮、苯丙氨酸态氮、谷氨酸态氮+苯丙氨酸态氮,这些处理中除了N素形态不同外,其N、P、K的含量均相同。研究不同处理对番茄生长的影响,并在此基础上利用生态化学计量学的方法研究了氨基酸态氮和NO3--N混合营养下番茄生长及其与生态化学计量学特征之间相关关系。研究结果表明,番茄植株光合速率与其地上部C/P之间存在显著正相关关系;番茄地上部硝酸盐含量、亚硝酸盐含量、游离氨基酸含量、硝酸还原酶活性和谷氨酰胺合成酶活性与其地上部N/P、C/N、C/P和P/K之间均不存在显著相关关系;和N源为NO3--N的处理相比,氨基酸态氮和NO3--N混合营养促进番茄(地上部和根系)生长,两种氨基酸态氮和NO3--N混合的营养效应好于单一氨基酸态氮和NO3--N混合的营养效应。  相似文献   

7.
The effect of three levels of salinity (2.0,4.0, and 8.0 mS/cm) on growth and ion composition of tomato and cucumber seedlings was examined with and without addition of 7.4 meq/L calcium chloriode (CaCl2). The corresponding sodium/calcium (Na/Ca) ratio of the irrigation solution were 4.0 and 1.8 at salinity level 4.0 mS/cm, and 12 and 4.8 at salinity level 8.0 mS/cm. Seedlings growth of tomato and cucumber was generally reduced with increasing salinity level. Cucumber was more salt‐sensitive than tomato. Shoot and root dry weight of cucumber was increased by decreasing Na/Ca ratio at 4.0 mS/cm salinity. Sodium and chloride (Cl) accumulation was increased and Ca was decreased in salinized plants. Reducing Na/Ca ratio under saline condition reduce the accumulation of Na in tomato roots. The effect of salinity on the uptake of nitrogen (N), phosphorus (P), potassium (K), Na, Ca, chloride (Cl), iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) in the root and shoot was also determined.  相似文献   

8.
In a lysimeter experiment the overall amino acid concentration in dry matter of ryegrass (Lolium perenne) increased in response to nitrogen application. Lack of water reduced the overall concentration of most amino acids in dry matter except proline the concentration of which was increased. Nitrogen application as well as lack of water significantly affected the overall amino acid composition, and in particular the relative concentration of glutamic acid and proline, respectively, which might be attributed to variations in the free amino acid composition, and resulting in a decreasing overall ratio essential/not essential amino acids.  相似文献   

9.
设施栽培黄瓜临界氮浓度和氮营养指数模拟   总被引:3,自引:1,他引:3       下载免费PDF全文
以黄瓜津春5号为试验材料,采用随机区组设计,2016和2017年分别设置了5个氮浓度梯度,构建了黄瓜地上部生物量的临界氮浓度稀释模型,在此基础上建立了氮素吸收模型和氮营养指数模型。结果表明,黄瓜地上部临界氮浓度与地上部最大生物量之间符合幂指数关系,%Nc=4. 539 7x-0. 06,相关系数为R2=0. 749 6。基于临界氮浓度建立的设施栽培黄瓜氮素吸收(Nupt)模型、氮素营养指数(NNI)模型,可作为设施栽培黄瓜氮素营养状况的判别指标,本试验条件下295. 7~305. 5 kg/hm~2为黄瓜最佳施氮量。  相似文献   

10.
The Ben Zioni ‐ Dijkshoorn hypothesis that NO3 uptake by roots is regulated by NO3 assimilation in the shoot was tested using the tomato plant. Plants were grown at three K levels and the fate of anion charge from NO3, and SO4 2‐. assimilation followed in its distribution between organic acid anion accumulation and HCO3 efflux into the nutrient medium. For the high K treatment almost all of this charge was directed towards organic acid accumulation with HCO3 efflux accounting for only 3% of the total charge. On the other hand for plants supplied at the low K level, a substantial proportion of the anion charge was excreted as HCO3 (32%).

Xylem sap analyses and NO3 reductase assay results indicated that in the tomato plant the upper plant parts constituted the major site for NO3 reduction. The quantitatively most important ionic constituents in the sap were K+, Ca2+ and NO3 .

Results have been presented that indicate that when K is in short supply in the nutrient medium, K recycling occurs within the plant to facilitate the upward transport of NO3 from root to shoot.  相似文献   

11.
A greenhouse experiment was designed in order to evaluate growth, water relations, and nutrient concentrations of grafted and ungrafted tomato plants grown under varying levels of salinity (0, 30, or 60 mM NaCl). Two cultivars, ‘Fanny’ and ‘Goldmar’, were grafted onto AR‐9704, using the cleft‐grafting method. Growth of grafted ‘Fanny’ plants was higher than that of ungrafted plants. Growth of ‘Goldmar’ plants was not affected by salinity treatments or grafting, but it was slower than for ‘Fanny’. Leaf turgor showed no significant differences between grafted and ungrafted plants or between salinity levels. The stomatal conductance (Gs) was higher for grafted than for ungrafted plants, and salinity decreased it significantly and progressively in both grafted and ungrafted plants and in both varieties. The concentrations of Na+ and Cl were significantly higher in ungrafted than in grafted ‘Fanny’ plants. ‘Fanny’ was more tolerant when grafted, probably due to reduced accumulation of Na+ and/or Cl in the shoot.  相似文献   

12.
Nitrogen (N) is taken up by most plant species in the form of nitrate (NO ) or ammonium (NH ). Plant response to continuous NH nutrition is species‐dependent. In this study, we compare the responses of tomato (Solanum lycopersicum L. cv. Rio Grande) plants to N source (NO or NH ). To this end, early plant growth, photosynthesis, chlorophyll, carbohydrate, and N‐compound concentrations as well as the activities of main enzymes involved in N metabolism (nitrate reductase, nitrite reductase, glutamine synthetase, and glutamate dehydrogenase) were analyzed. Early plant growth was remarkably ameliorated under NH ‐ in comparison to NO ‐based nutrition. Concomitantly, photosynthetic activity, total chlorophyll, and carbohydrate concentrations were significantly increased. With increasing external NH concentration, NH accumulated mainly in roots. In addition, root protein concentration was significantly increased, reflecting high NH incorporation into organic nitrogen. Root glutamine synthetase (GS) activity was enhanced by NH for concentrations below 5 mM, whereas root glutamate dehydrogenase (GDH) activity increased in parallel to NH availability. Together with the positive effect of NH on tomato plant cv. Rio Grande growth, these results reveal that GDH could have, in addition to GS, a possible role in NH detoxification and tolerance of NH ‐based nutrition.  相似文献   

13.
Environmental pollution and high costs of mineral fertilization have impelled scientists and farmers to use environmentally friendly fertilizers. An experiment was conducted to evaluate the effect of different combinations of rabbit manure (RM), rock phosphate (RH), feldspar (F), and bio-fertilizers [Microbine (Bio-N), Phosphorin (Bio-P) and Potassiumag (Bio-K)] on the growth, yield, and quality of tomato (Lycopersicon esculentum Mill.) plants. The mixture of RM, RH, and F + Bio-N-P-K increased the tomato fruit yield by 30% compared to inorganic fertilization. The application of RM, RH, and F with the bio-fertilizer (Bio-N-P-K) inoculation increased the concentration of N, P, and K in the leaves of tomato by 34%, 35%, and 50% in comparison to the same treatment without the bio-fertilizer. The current study clearly depicted that natural minerals (RH and F) and nitrogen, phosphorus, and potassium bio-fertilization lead to higher yields and better fruit quality than conventional fertilization.  相似文献   

14.
Duck eggs were pickled in alkali for 20 days to prepare Pidan. The extent of the degradation of compositional amino acids, the formation of lysinoalanine (LAL) in Pidan, and the relationship between the formation of LAL and the racemization values of D-serine and D-aspartic acid in Pidan albumen during the pickling period were investigated. Results showed that the remaining percentages of Cys, Arg, Lys, Ser, and Thr in albumen were much lower than that of the corresponding amino acid in yolk. The formation of LAL in albumen in the first stage was due to the speedy increase in the pH and the abundant formation of dehydroalanine (DHA) from cysteine. However, the formation of LAL in the later pickling period was related much more to the alkali-treating time than to the pH factor. Among the amino acids, cysteine was observed to be the most sensitive to alkaline and contributed mostly to the formation of LAL throughout the pickling period.  相似文献   

15.
通过设置N0(不施氮)、N1(150 kg/hm2)、N2(300 kg/hm2)和N3(450 kg/hm2)4个氮水平的田间小区试验,利用反射仪法对加工番茄新功能叶的叶柄进行硝酸盐测定,并测定地上部分生物量与经济产量,研究叶柄硝酸盐浓度与产量、叶全氮量、植株全氮量、地上部分干物质量等的相关性,建立加工番茄叶柄硝酸盐诊断追肥模型。结果表明,优化施氮处理(N2)经济产量为95 259 kg/hm2,较不施氮处理(N0)增产50 812 kg/hm2,增收14 988元/hm2。各处理加工番茄叶柄硝酸盐浓度随生育期进展呈一致的变化趋势,且叶柄硝酸盐含量在一定范围内随施氮量的增加而增大。加工番茄不同生育时期叶柄硝酸盐浓度与产量均呈显著相关性。经过校检,加工番茄以盛果前期为氮营养诊断时期较为合理,其临界值为4 182 mg/L。同时,初步建立了植株硝酸盐诊断追肥模型。  相似文献   

16.
设施土壤有机氮组分及番茄产量对水氮调控的响应   总被引:2,自引:0,他引:2  
【目的】酸解铵态氮和酸解氨基酸氮是土壤有机氮的主要组分,可表征土壤的供氮能力,并在氮素矿化、固定、迁移以及为植物生长供氮过程中起到至关重要的作用。研究水、氮调控下设施土壤有机氮组分和番茄产量的相互关系,为评价设施土壤肥力变化和制定科学合理的水、氮管理措施提供科学依据。【方法】田间定位试验在沈阳农业大学的温室内进行了5年,供试作物为番茄,栽培垄上覆盖薄膜,打孔移栽番茄幼苗,膜下滴灌。定位试验三个氮肥处理为施N75、300、525kg/hm^2,记为N1、N2和N3;三个灌水量为25、35和45kPa灌水下限(灌水始点土壤水吸力),记为W1、W2和W3,共9个肥水处理组合。在试验第五年番茄生长期(2016年4—8月)调查了番茄产量及其构成,在休闲期(2016年9月)测定0—10、10—20和20—30cm土层土壤有机氮组分、有机碳和全氮含量。【结果】9个处理中,土壤全氮、有机碳和除酸解氨基糖氮外的有机氮组分含量均随土层深度的增加而降低,且0—10、10—20和20—30cm土层间含量差异显著(P<0.05)。三个土层中酸解总氮占土壤全氮的66.0%、64.6%和55.2%,是土壤有机氮的主要存在形态。土壤酸解总氮中各组分含量及其所占比例的大小顺序为酸解氨基酸氮、酸解铵态氮>酸解未知态氮>酸解氨基糖氮。灌水下限和施氮量对番茄产量及单果重的影响均达极显著水平(P<0.01),水氮交互效应也达显著水平(P<0.05)。休闲期土壤酸解铵态氮与番茄产量间显著负相关(P<0.05)。番茄产量W1N2(25kPa+N300kg/hm^2)、W2N1(35kPa+N75kg/hm^2)和W1N1(25kPa+75kg/hm^2)处理间差异不显著。【结论】灌水和施氮量及其交互效应对各土层土壤全氮、酸解总氮、酸解铵态氮和酸解氨基酸氮的影响均达到极显著水平(P<0.01),而对土壤有机碳的影响不显著(P>0.05)。相同施氮量下,0—30cm土层酸解铵态氮和0—20cm土层酸解氨基酸氮含量均在土壤水吸力维持在35~6kPa范围内达最高值,此土壤水分含量下的0—20cm土层酸解氨基酸氮含量在施N75kg/hm^2时达到最大值。从节水减氮和番茄产量的角度考虑,控制土壤水吸力不低于35kPa、每季随水施N75kg/hm^2为供试番茄生产条件下最佳的水、氮组合量。  相似文献   

17.
Low molecular weight organic substances (LMWOS) in soil and soil solution include mainly amino acids, carboxylic acids, and carbohydrates. Due to their high bioavailability they play a crucial role in the cycles of C and nutrients in soils. The variety of soil processes that involve LMWOS requires identifying their composition to elucidate reactions and transformations. In most studies, LMWOS are extracted under artificial conditions, e.g. batch experiments, which may overestimate the actual concentrations. This study measures the composition of carbohydrates and amino acids in solution of a Haplic Luvisol leached in a column experiment. A combined system for simultaneous leaching and blowout of CO2 was used to estimate LMWOS decomposition. 14C-labeled glucose was added as a highly sensitive tracer to control the efficiency of the LMWOS extraction by leaching and to estimate LMWOS decomposition during leaching. High performance liquid chromatography (HPLC), optimized for soil extracts, was used to analyze LMWOS composition. For HPLC optimization, different preparations of leached solutions (filtration vs. centrifugation, and drying vs. no-drying) were compared. For sugar determination, drying had no influence on the solution concentrations. In contrast, amino acid concentrations significantly decreased by drying LMWOS eluted substances. Combining the HPLC identification of eluted substances with 14C tracer application revealed that about 5% of the glucose could be leached unchanged within 786 min (13.1 h), whereas about 84% remained in the soil, 9% were decomposed to CO2, and 2% were transformed to other LMWOS and recovered in the soil solution. The total amino acid concentration (TAC) in soil solution was about 8.2 μmol l−1, dominated by alanine (14.4% of TAC), glycine (13.4%), glutamic acid (9.9%), serine (9.4%), and leucine (9.3%). The total carbohydrate concentration was about 2.4 μM, dominated by glucose (29.9%), glucuronic acid (26.8%), and galacturonic acid (17.3%). Ratios of hexoses to pentoses, amino sugars glucosamine to galactosamine, and neutral sugars to uronic acids were determined. All three parameters pointed to the dominant influence of plants as the source of LMWOS in the leached soil solution. Within the small contribution of microorganisms, bacteria dominated over fungi. These used biomarker ratios as well as LMWOS concentrations differed widely from the ones obtained with conventional batch extraction. More research is necessary to evaluate the application of these biomarkers to soil solutions.  相似文献   

18.
 The total N content in the acid forest soils studied ranged between 0.41% and 1.43%, and in more than 98% was composed of organic N. Total hydrolysable organic N, hydrolysable unknown N (HUN) and α-aminoacidic N represented around 70%, 34% and 20% of the organic N, respectively, and varied in wide ranges. The percentages of amidic N and of the organic N compounds solubilised to NH4 + were approximately 6% and 5%, respectively, and ranged in narrow intervals. Aminoglucidic N reached a maximum of 3.8% of the organic N and was undetectable in some of the samples analysed. Most of the hydrolysable N, HUN and α-aminoacidic N was solubilised with 1 N and 3 N HCl, while a high amount of the compounds recovered as NH4 + (60%) was obtained with 6 N HCl. The distribution of aminoglucidic N in the four fractions of increasing hydrolytic intensity was very irregular. The organic N composition in the 0 to 5-cm and 5 to 10-cm layers was not significantly different. The variation among samples was determined mainly by the organic N compounds less resistant to acid hydrolysis (hydrolysable N and HUN less resistant to acid hydrolysis, amidic N and labile ammoniacal N) and by all α-aminoacidic N fractions. Aminoacidic N was positively correlated with electrical conductivity and negatively correlated with exchangeable Al. The net N mineralisation over 10 weeks of incubation was positive in all the soil samples analysed. The inorganic N content after the incubation and the microbial N content were positively correlated with other variables – mainly with amidic N and α-aminoacidic N, as well as with HUN and the hydrolysable N less resistant to hydrolysis. Received: 13 July 1999  相似文献   

19.
Soil organic nitrogen (ON) accounts for more than 90%of the total nitrogen (TN) in paddy soils. Inadequate understanding of the different ON fractions in paddy soils and their corresponding bioavailability under different climatic conditions has constrained the development of appropriate nutrient management strategies for rice production. In this study, we applied a modified Bremner method coupled with high-performance liquid chromatography to characterize how soil ON fractions and amino acid ch...  相似文献   

20.
氮素形态对樱桃番茄果实氮素和有机酸代谢的影响   总被引:1,自引:0,他引:1  
Cherry tomatoes(Lycopersicon esculentum Mill.,cv.hongyangli) were hydroponically cultivated in a greenhouse to determine the effect of different nitrogen(N) forms on organic acid concentration and the activities of related enzymes involved in nitrogen and organic acid metabolism during cherry tomato fruit development.The results showed that fruit nitrate reductase(NR) activity was much higher following treatment with 100% NO 3 and 75% NO 3 + 25% NH + 4 than with 100% NH + 4 except at maturity.Glutamine synthetase(GS) activity trended downward during fruit development under all three treatments.Plants fed 100% NH + 4 had the lowest fruit citrate and malate levels at maturity,with the highest malate concentration at an early stage.The activity of phosphoenolpyruvate carboxylase(PEPC) was found to be in accord with the malate concentration with every N source.Under all three N forms,the citrate synthase(CS) activity peaked one week before the citrate concentration.  相似文献   

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