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1.
小麦和玉米叶面标记尿素态15N的吸收和运输 总被引：13，自引：0，他引：13
以15N标记的尿素作为叶面施肥和根系后期追肥的N肥品种,分别采用土培与砂培研究小麦与玉米拔节后至灌浆初期不同生育期、不同N、P和K肥叶面配施后作物对叶面N肥利用效率、叶面施用N肥的分配及对全株N、P和K养分状况的影响。无论是小麦还是玉米叶片均能有效地吸收N素并将其迅速转移。玉米拔节期下位叶（第5叶）施肥,植株吸收的15N转移到根部的比例平均为9.0%,而中位叶（第8叶）处理,分配到根系的比例仅为2.4%。叶面施用尿素态氮肥的N在小麦地上部的回收率一般在54.5%～68.9%,在玉米全株体内的回收率可达59.9%～75.3%。随生育期推迟,两种作物叶片吸收N的回收利用率均明显提高。与单施氮肥相比,N,P和K肥配施均有提高氮素回收率和改善作物地上部N素营养的作用,尤以中位叶（第8叶）配施尿素＋KH2PO4的效果最佳,表明植物的叶面营养仍应注意平衡供应和适宜的施用时期与施肥部位。叶面大量元素营养不仅改善了所施肥料成分中相应元素的营养状况,同时也促进了对其他两种成分的吸收,并且提高了N、P转运到籽粒中去的比例。玉米吐丝期根系追施的尿素态N有56%积累在籽粒中,而叶面施肥所利用的N分配在籽粒中的比例为70%。 相似文献
2.
LiXin Zhang MingYu Han CaiPing Zhao ChangHong Liu FangFang Zhang LinSen Zhang 《Journal of plant nutrition》2013,36(10):1557-1571
Total nitrogen (N) concentration (N%), N derived from 15N-fertilizer (Ndff%), amount of 15N uptake (ANU) in main organs (leaves, shoots, roots, fruits), and N use efficiency (NUE) were measured to assess N absorption, distribution, and utilization of Red Fuji apple trees across two years using a 15N-enriched urea method. The N% in leaves and fruits decreased while those in shoots and roots increased in both years. The Ndff% and ANU in roots were highest at fruitlet stage than those in leaves, shoots and fruits at mature stages. This suggested that the absorbed 15N by roots was redistributed to new organs. The N% was lower while Ndff% and ANU were greater in 2008 than 2007. The most 15N absorbed was accumulated in the trunks, main and coarse roots and smaller in the fine roots and biennial branches. The NUE in 2007 and 2008 reached 9.9% and 12.2% respectively. 相似文献
3.
Nguyen Van Phi Hung Shiori Watanabe Shinji Ishikawa Norikuni Ohtake Kuni Sueyoshi Takashi Sato 《Soil Science and Plant Nutrition》2013,59(6):888-895
The quantitative analysis of the initial transport of fixed isotope 15-nitrogen (15N) in intact nodulated soybean plants (Glycine max [L.] Merr. cv. Williams) was investigated at the vegetative stage (36 days after planting, DAP) and pod-filling stage (91 DAP) by the 15N pulse-chase experiment. The nodulated roots were exposed to N2 gas labeled with a stable isotope 15N for 1 h, followed by 0, 1, 3 and 7 h of exposure with normal air. Plant roots and shoots were separated into three sections (basal, middle and distal parts) with the same length of the main stem or primary root. Approximately 80 and 92% of fixed N was distributed in the basal part of the nodulated roots at the vegetative and pod-filling stages by the end of 1 h of 15N2 exposure, respectively. In addition, about 90% of fixed 15N was retained in the nodules and 10% was exported to root and shoot after 1 h of 15N2 exposure at 91 DAP. The percentage distribution of 15N in the nodules at the pod-filling stage decreased from 90% to 7% during the 7 h of the chase period, and increased in the roots (14%), stems (54%), leaves (12%), pods (10%) and seeds (4%). The 15N distribution was negligible in the distal root segment, suggesting that N fixation activity was negligible and recycling fixed N from the shoot to the roots was very low in the initially short time of the experiment. 相似文献
4.
Soil or foliar application of nitrogen (N) can increase plant growth and salinity tolerance in cotton, but a combination of both methods is seldom studied under salinity stress. A pot experiment was conducted to study the effects of soil application (S), foliar application (F), and a combination of both (S+F) with labeled nitrogen (15N) on cotton growth, N uptake and translocation under salinity stress (ECe = 12.5 dS m?1). Plant biomass, leaf area, leaf chlorophyll (Chl) content, leaf net photosynthetic (Pn) rate, levels of 15N and [Na+] and K+/ Na+ ratio in plant tissues were determined at 3, 7, 14 and 28 days after N application (DAN). Results showed that soil or foliar nitrogen fertilization improved plant biomass, leaf area per plant and leaf photosynthesis, and a combination of soil- plus foliar-applied N was superior to either S or F alone under salinity stress. Although foliar application favored a rapid accumulation of leaf N and soil application a rapid accumulation of root N, S+F enhanced N accumulation in both leaf and root under salinity stress. The combined N application also maintained significantly greater [K+] and K+/Na+ than either soil or foliar application alone. Therefore, the improved plant growth and salinity tolerance under S+F relative to soil or foliar N application alone was attributed to the increased total uptake of N, balanced N concentrations in different tissues through enhanced uptake and accumulation in both leaves and roots, and higher ratio of K+/Na+. 相似文献
5.
The influence of mineral fertilization on root uptake and arbuscular mycorrhizal fungi-mediated 15N capture from labeled legume (Medicago polymorpha) residue was examined in winegrapes (Vitis vinifera) in the greenhouse, to evaluate compatibility of fertilization with incorporation of cover-crop residue in winegrape production.
Plants grown in marginal vineyard soil were either fertilized with 0.25× Hoagland’s solution or not. This low fertilization
rate represents the deficit management approach typical of winegrape production. Access to residue in a separate compartment
was controlled to allow mycorrhizal roots (roots + hyphae), hyphae (hyphae-intact), or neither (hyphae-rotated) to proliferate
in the residue by means of mesh core treatments. Leaves were weekly analyzed for 15N. On day 42, plants were analyzed for 15N and biomass; roots were examined for intraradical colonization; and soils were analyzed for 15N, inorganic N, Olsen-P, X-K, and extraradical colonization. As expected, extraradical colonization of soil outside the cores
was unaffected by mesh core treatment, while that inside the cores varied significantly. 15N atom% excess was highest in leaves of roots + hyphae. In comparison, leaf 15N atom% excess in hyphae-intact was consistently intermediate between roots + hyphae and hyphae-rotated, the latter of which
remained unchanged over time. Fertilization stimulated host and fungal growth, based on higher biomass and intraradical colonization
of fertilized plants. Fertilization did not affect hyphal or root proliferation in residue but did lower %N derived from residue
in leaves and stems by 50%. Our results suggest that even low fertilization rates decrease grapevine N uptake from legume
crop residue by both extraradical hyphae and roots. 相似文献
6.
7.
Katherine Bravo Graziella Marcolini Giovambattista Sorrenti Elena Baldi Maurizio Quartieri 《Journal of plant nutrition》2017,40(5):719-725
Walnut tree requires a relatively high amount of nitrogen (N). To avoid loss in the environment, N uptake efficiency (NUE) should be optimized. The aims of this study were to evaluate the effect of time of N application on NUE, partitioning, and remobilization in walnut trees. Two-year-old trees were planted in 40-L pots and fertilized with 1 g of 15N-enriched (5 atom %) N at: 1) bud burst, 2) pistillate flower maturity, and 3) late summer. One week after fertilization, the percentage of N derived from fertilizer and NUE were higher in trees fertilized in late summer, than other timings. N uptake was linearly related to root dry weight. At May 2008 harvest, the N stored in trunk and twigs was remobilized to the developing leaves and to the roots. Late summer N application appeared to be the most effective in providing N for walnut spring new growth. 相似文献
8.
Foliar uptake of 15NH3 applied at two growth stages (tillering and anthesis) and the subsequent 15N-labelled vegetative-N distribution in different plant components at maturity was investigated in three rice cultivars, IR-6, NIAB-6 and Bas-385. Rice plants absorbed 22–30% and 18–24% of the 15NH3 applied at tillering and anthesis stages, respectively. Of the total 15NH3 absorbed at tillering stage, IR-6 and Bas-385 showed higher recovery (71%) in different plant components at maturity as compared to NIAB-6 (48% recovery). At maturity, percent recovery of the 15NH3 absorbed at anthesis stage was almost comparable in different cultivars, but it was lower (46–55%) than that absorbed at the tillering stage. Recovery of the absorbed 15NH3-N in the soil was negligible and ranged from 0.3–1%. At maturity, the cultivars IR-6 and Bas-385 showed a higher loss (45–53%) of 15NH3 absorbed at anthesis than at the tillering stage (29% loss), whereas for NIAB-6, the corresponding figures were comparable for the two growth stages (tillering, 51% loss; anthesis, 49% loss). Results indicated a variable potential of the tested rice cultivars for foliar uptake of atmospheric 15NH3 and distribution of 15N-labelled vegetative-N in different plant components. 相似文献
9.
The natural 15N abundances (δ15N values) were measured for nitrate and free and bound amino acids from the leaves of field-grown spinach (Spinacia oleracea L.) and komatsuna (Brassica campestris L.), as well as ureides and free and bound amino acids in the leaves and roots of hydroponically grown soybean (Glycine max L.) totally depending on dinitrogen. Nitrate from the spinach and komatsuna leaves and ureides from leaves and roots of soybean showed higher δ15N values than the total tissue N and N in free or bound amino acid fractions. The δ15N values of individual free and bound amino acids, determined by GC/C/MS using their acetylpropyl derivatives, were similar in leaf tissues except for proline but varied in soybean root tissues. The order of 15N enrichment was similar in the four samples: aspartic acid > glutamic acid > threonine, proline, valine > glycine + alanine +serine, γ-amino butyric acid, and phenylalanine. 相似文献
10.
B. R. Lee S. Muneer W. J. Jung J. C. Avice A. Ourry 《Journal of plant nutrition》2014,37(10):1702-1716
Sulfur (S) deficiency effects on nitrogen (N) and S fluxes during vegetative growth of Brassica napus was investigated by tracing 15N and 34S for 9 d of S-sufficient [1.5 mM sulfate (SO42-)] and S-deficient (0.05 mM SO42-) condition. A significant decrease in leaf osmotic potential and chlorophyll content was apparent after 9 d of S-deficiency. Sulfur uptake during 9 d was remarkably decreased by 94.3% by S-deficiency, whereas no significant change occurred for N uptake. The N and S deriving from uptake were mainly allocated to the leaves in control plants, but the S flow into leaves was largely restricted under S-deficient condition. The remobilization of stored N and S were mainly issued only from leaves in control plants, while from leaves and petiole in S-deficient ones. The remobilization of N and S mainly issued from leaves flows into the roots both in control and S-deficient plants. 相似文献
11.
【目的】采用15N、13C同位素示踪技术,通过对不同施氮量下嘎啦幼苗生长状况及氮、碳分配、利用特性等的研究,以期为苹果生产合理施肥提供依据。【方法】将2年生盆栽嘎啦幼苗进行低、中、高三个氮水平处理,同时进行15N标记。在新梢旺长初始期、新梢旺长期、新梢缓长期分别进行整株13C标记,72小时后,整株解析为叶、梢、根三部分,进行15N、13C测定。样品全氮用凯氏定氮法测定,15N丰度用ZHT-03质谱计测定。13C丰度用DELTA V Advantage同位素比率质谱仪测定。【结果】1)中、高氮水平的施肥处理可在不同程度上提高整株及叶片干物质量和新梢长度。新梢旺长初始期和新梢缓长期嘎啦幼苗整株干物质量、新梢旺长期叶片干物质分配比率在中、高氮水平处理间差异不显著,中氮水平经济有效。新梢旺长期以后新梢长度以中氮高氮低氮,三者间差异性显著,中氮处理有利于新梢生长。2)在新梢旺长初始期,低氮处理植株叶片15N分配率达50%,比其他处理高出13个百分点左右,表明低氮处理更多的氮被叶片所利用,中氮和高氮处理间差异不显著,说明在本试验施氮条件下中氮供应水平已能满足氮素营养需求。3)新梢旺长期和新梢缓长期幼苗13C固定量均以中氮处理最高,新梢旺长初始期3个处理间根系13C分配率中氮高氮低氮,表明中氮处理有利于碳同化物在嘎啦幼苗中的分配。4)不同施氮量处理的嘎啦幼苗,15N利用率随施氮水平提高而降低,高氮处理对碳同化物分配没有显著贡献。【结论】低、中、高氮不同处理新梢缓长期碳同化物在各器官间的分配比较均衡,氮素水平不能影响碳同化物的分配。盆栽试验表明,中氮水平在保证营养供应的同时,能够促进新梢生长和树势健壮。 相似文献
12.
The impact of urea prills (1–2 mm) versus urea supergranules (USGs, ～10 mm), placed at different depths, on the growth and nitrogen (N) use efficiency of spring wheat was investigated under greenhouse conditions. The amount of fertilizer 15N derived from either form was 50% greater in the top soil than at lower depths. The comparatively slower release and distribution of USG-N resulted in enhanced dry matter production and fertilizer-N uptake during the later growth stages that were also associated with a higher translocation of fertilizer-15N into the grain (34.9% versus 28.7% for the prills). Deeper placements of USGs (5.0–7.5 cm) resulted in greater fertilizer-N recovery in the crop (70.5–78.0%) compared to the use of prills (56.6%). Our results strongly suggest that the proper application of USGs can increase yields and fertilizer-N utilization of wheat and simultaneously decrease N losses compared to equivalent use of prills, and therefore presents important agronomic advantages. 相似文献
13.
Two methods of N transfer between plants—by litter decomposition and root-to-root exchange—were examined in mixed plantations of N-fixing and non-fixing trees. Nitrogen transfers from decaying litters were measured by placing 15N-labelled litters from four actinorhizal tree species around shoots of containerized Prunus avium. Nitrogen transfers by root-to-root exchanges were measured after foliar NO3-15N fertilization of Alnus subcordata and Elaeagnus angustifolia growing in containers in association with P. avium. During the first 2 years of litter decomposition, from 5–20% of the N, depending on the litter identity, was released and taken up by P. avium. N availability in the different litters was strongly correlated with the amount of water-soluble N, which was highest in leaves of E. angustifolia. In the association between fixing and non-fixing plants, 7.5% of the A. subcordata N and 25% of E. angustifolia N was transferred to P. avium by root exchange. These results showed that the magnitude of N transfers by root exchange depended on the associated N2-fixing species. Among the species investigated, E. angustifolia displayed the highest capacity for exudating N from roots as well as for releasing N from litters. These qualities make this tree a promising species for enhancing wood yields in mixed stands. 相似文献
14.
AbstractBarley (Hordeum vulgare L.) is an important crop for cereal research. In this study, two barley genotypes the wild-type (Steptoe) and the mutant (Az12) were used. An experiment was conducted using 15N-tracing method to NADH-specific nitrate reductase (NR)-deficient mutant seedling of barley. The N-depleted seedlings were exposed to a nutrient solution containing nitrate and nitrite, and were labeled with 15N for 38?h under (14?L/10D) cycles. The two genotypes utilized 15NO3? and accumulated it as reduced 15N, predominately in the shoots. However, nitrate reduction in the Az12 shoots was 9% lower than that in the Steptoe shoots at 38?h. As a result, in the Az12, nitrate accumulation in shoots was 78% higher than that in the Steptoe. Accumulation of reduced 15N in the Az12 roots was nearly similar to that of the Steptoe roots, but 8% lower in the Az12 shoots than in the Steptoe shoots at the end of the experiment. Also for both genotypes, root contribution increased during L/D cycles and decreased during the subsequent light cycle. Upward transport of reduced 15N via the xylem in the Az12 was nearly two times higher than that in Steptoe during the second light period (24–38?h). In both genotypes, xylem transport of reduced 15N was far exceeded the downward phloem transport. Abbreviations Anl accumulation of reduced 15N from 15NO3? in non-labeled roots of split roots Ar accumulation in roots of reduced 15N from 15NO3? As accumulation in shoots of reduced 15N from 15NO3? Rr 15NO3? reduction in roots Rs 15NO3? reduction in shoots Tp translocation to root of shoot reduced 15N from 15NO3? in phloem Tx translocation to shoot of root-reduced 15N from 15NO3? in xylem FW fresh weight 相似文献
15.
设施栽培油桃对叶面施15N的吸收、分配特性研究 总被引：1，自引：1，他引：1
以设施栽培的5年生早红珠油桃/山毛桃为试材,应用15N示踪技术研究油桃叶片对15N-尿素的吸收及运转特性。结果表明,叶片施用15N-尿素标记叶吸收主要发生在叶片涂抹15N-尿素后6.h内,平均吸收速率为0.204mg/(g.h);标记叶中15N吸收量24.h达到最高,新梢和梢顶嫩叶15N含量在施用15N-尿素48.h达到最高,下部叶15N含量很低,没有明显的峰;处理168.h各器官中15N含量为标记叶梢顶嫩叶新梢下部叶;试验结束时分配势Ndff(即各器官N含量来自化肥N所占的百分率)为标记叶中最高,然后依次为梢顶嫩叶、新梢、下部叶。这说明氮素迅速被吸收并运到嫩梢和嫩叶中,从而促进这些新生器官的形态建造,可起到以N增C的作用。不同叶面处理的试验还表明,正面和背面全部涂抹的叶片15N含量最高,只涂抹叶片背面次之,涂抹正面最低。设施栽培油桃叶片可迅速吸收尿素,其吸收量早晨明显优于中午和下午,因此设施油桃栽培管理中于早晨进行叶面施尿素,且正反面兼顾,N素的吸收利用效果最好。 相似文献
16.
晚秋叶施尿素提高矮化苹果翌春生长及果实品质的效果 总被引：1，自引：0，他引：1
17.
15N studies were conducted using hydroponically grown tea (Camellia sinensis L.) plants to clarify the characteristics of uptake, transport and assimilation of nitrate and ammonium. From the culture solution containing 50 mg L-1 N03-N and 50 mg L-1 NH.-N, the uptake of NH3-N after 24 h was twice as high as that of NO3-N, while the uptake of N03-N from the culture solution containing 90 mg N03-N and 10 mg NH3-N was twice that of NH4-N. The presence of 0.4 mM Al had no significant effect on the N03-N and NH4-N uptake from the culture solutions containing 50 mg L-1 N03-N and 50 mg L-1 NH4-N, 90 mg L-1 N03-N and 10 mg L-1 NH4-N or 99 mg L-1 N03-N and 1 mg L-1 NH4-N. Transport of N03-derived N to young leaves was much more rapid than that of NH4-derived NO3 and NH4-derived N was largely retained in the roots and lower stem. Young and mature shoots separated from the roots absorbed more N03-N than intact plants. Nitrate assimilation occurred in both, roots and young as well as mature leaves. Internal cycling of N03-derived Nand NH4-derived N from one root part to another part was not appreciable after 28 h, suggesting that a longer of time is required for cycling in woody plants. 相似文献
18.
Summary We studied the effect of three successive cuttings on N uptake and fixation and N distribution in Leucaena leucocephala. Two isolines, uninoculated or inoculated with three different Rhizobium strains, were grown for 36 weeks and cut every 12 weeks. The soil was labelled with 50 ppm KNO3 enriched with 10 atom % 15N excess soon after the first cutting. Except for the atom % 15N excess in branches of K28 at the second cutting, both the L. leucocephala isolines showed similar patterns of total N, fixed N2, and N from fertilizer distribution in different parts of the plant at each cutting. The Rhizobium strain did not influence the partitioning of 15N among the different plant parts. Significant differences in 15N enrichment occurred in different parts. Live nodules of both isolines showed the lowest atom % 15N excess values (0.087), followed by leaves (0.492), branches (0.552), stems (0.591), and roots (0.857). The roots contained about 60% of the total plant N and about 70% of the total N derived from fertilizer over the successive cuttings. The total N2 fixed in the roots was about 60% of that fixed in the whole plant, while the shoots contained only 20% of the fixed N2. We conclude that N reserves in roots and nodules constitute another N source that must be taken into account when estimating fixed N2 or the N balance after pruning or cutting plants. 15N enrichment declined up to about fivefold in the reference and the N2-fixing plants over 24 weeks following the 15N application. The proportion and the amounts of N derived from fertilizer decreased, while the amount derived from N2 fixation increased with time although its proportion remained constant. 相似文献
19.
Zhongwei Tian Xiaoxue Liu Jinhong Yu Shilu Gu Lei Zhang Dong Jiang 《Archives of Agronomy and Soil Science》2020,66(10):1384-1398
ABSTRACT A two-year field and micro-plot 15N-labelled experiment was conducted under two levels of N application rate (240 and 180 kg N ha–1) with three basal N application stages [seeding (L0), four-leaf stage (L4), and six-leaf stage (L6)] to investigate the effects of reducing basal N application amount and postponing basal N fertilization period on wheat growth and N use efficiency (NUE). No significant differences were observed in grain yield, root growth and root morphology between the N180L4 and N240L0 treatments, while the root-shoot ratio of N180L4 was significantly improved. Postponing basal N application period increased the residual basal 15N in soil and reduced basal 15N loss, and N180L4 treatment favored the highest 15N recovery efficiency (NRE), mainly due to reduced 15N loss. Grain yield and basal NRE were significantly positively correlated with root dry weight in deeper soil layers (40–60 cm), and the contribution of root growth to improved grain yield and NRE increased with the downward distribution of the roots. Therefore, postponing the basal N fertilization period under N deficiency promotes deeper root growth during the post-jointing period and increases basal N uptake, as well as reducing basal N loss and increasing grain yield and NUE. 相似文献
20.
This experiment was carried out to determine whether the delay in rice growth associated with wheat straw application, especially at the early stage, was due to the acceleration of N assimilation or N uptake inhibition. Tracer 15N was used for rice plants cultivated in pots. After 24 h of tracer application the plants and soils were sampled for analysis. Seventeen days after transplanting, N uptake of rice decreased and the amount of unavailable tracer remaining in soil increased by wheat straw application. At the booting stage, 6 d before heading, N uptake was larger and the amount of remaining tracer was lower in the plots in which wheat straw was applied than in the control. It was obvious that the decrease of N uptake by wheat straw application was caused by N uptake inhibition and not by N starvation for a period of time at the early stage. The inhibition was removed at the booting stage. 相似文献