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1.
S. Müller 《Journal of Agronomy and Crop Science》1992,168(4):272-277
N-uptake and N utilization of different fertilizer types by winter wheat – pot experiments with 15 N
The efficiency of top dressing urea, ammonium nitrate and ammonium sulphate fertilizers on winter wheat grown on loamy sand and loessial black soil was studied. At a rate of 0.5 g N per pot on the loamy sand 20 % volatilization losses of NH3 occurred with urea and 10 % on the loessial black soil with urea resp. ammonium sulphate.
The grain yields an N removal correspond to these results. At an amount of 1.6 g N per pot the N-uptake of15 N ranged from 0.589 g (urea) on sandy soils to 1.279 g (ammonium nitrate) which agrees with 76 % an 91 % of the total N uptake. On black soil 0.675 g (urea) and 1.038 g (ammonium nitrate) or 44 % and 51 % of the total uptake are found. 相似文献
The efficiency of top dressing urea, ammonium nitrate and ammonium sulphate fertilizers on winter wheat grown on loamy sand and loessial black soil was studied. At a rate of 0.5 g N per pot on the loamy sand 20 % volatilization losses of NH
The grain yields an N removal correspond to these results. At an amount of 1.6 g N per pot the N-uptake of
2.
Ten charges of 15 N-labelled straw with different C/N ratios were incubated with lightly loamed sand at 25 °C and 50 % of the maximum water capacity. At the start of the 18-week incubation, mineral nitrogen was added and the 15 Nmin (NH4 and NO3 -N) content was determined six times during the course of the experiment. A slow release of 15 N was observed. After 111 days, between 2.5 and 13.0% of the total applied 15 N was mineralized. The addition of ammonium sulphate caused an increasing degradation of organic N compounds of the straw material even during the first weeks. Finally, between 6.4 and 33.3 %15 N was released. The 15 N release only partially shows the straw degradation. 相似文献
3.
The effects of exposure in the vegetative phase of growth to 5- or 10-day spells of soil drought (30% field water capacity) on assimilation, dissimilation and accumulation of 14 C and on dry matter growth were studied in two maize hybrids, nos. 8344 and 8388 (Garst Seed Co.) of high and low drought tolerance. Under control water regime in soil there was no difference in 14 CO2 uptake and dry matter growth between hybrids. After five days of drought 14 CO2 assimilation dropped by about 75% referred to unit weight of dry matter in hybrid 8344 and by 56% in hybrid 8388. After 10 days of drought 14 CO2 assimilation rate was reduced by 75% in both hybrids. Soil drought increased the 14 C dissimilation. There were no significant differences between hybrids in all treatments, with the exception of 5 days drought; after this treatment the dissimilation rate of hybrid 8344 was higher than that of 8388. Changes of translocation of 14 C and its accumulation in particular organs occurred in drought treated plants; the amount of 14 C accumulated in roots of plants of hybrid 8344 increased, while that of hybrid 8388 decreased. Changes of 14 C accumulation in roots were positively correlated to changes of dry matter of those organs. One day after 10 days of drought assimilation and dissimilation rates in both hybrids were about 60% of controls. 相似文献
4.
An experiment was conducted in field experiment plot to investigate nitrogen transportation from hulls of pods in different periods at early stage of siliqua developing and effect of KH2 PO4 and MgSO4 application on it using 15 N-urea.
More than 80 % of15 N applied on the surface of pods at lower terminal during flowering was recovered from all pods one month after flowering, most of them were still in the hulls of labelled pods, 17-27 % of l5 N applied was transported into seeds, a small amount was transported to pods at upper terminal, a little amount was found in pods at branch. More l5 N applied in middle period of flowering was transported to pods at upper terminal and branch than those applied in early period of flowering. It should be further investigated to conclude how will be going on transportation of nitrogen from hulls as preceding of siliqua developing towards maturity of seeds and its difference between 15 N applied in more different periods.
Application of KH2 PO4 and MgSO4 with 15 N-urea of surface of pods promoted transportation of 15 N into seeds from hulls, effect of MgSO4 was more notable. 相似文献
More than 80 % of
Application of KH
5.
A pot experiment was conducted to investigate the translocation of N in pods during siliqua developing of oilseed rape using 15 N-urea. The 15 N was applied on the surface of pods at lower stem in three periods after flowering. At maturity the hulls and seeds of pods at different parts of plants were subjected to analyse N content and 15 N abundance and calculate recoveries of N applied.
79.1–84.3 % of labelled N applied were recovered from the total pods including 75.3–80.4 % in labelled pods. A great part of the N was translocated in seeds, the later the labelled N application, the more proportion of N in seeds was. Application of MgSO4 combined with urea promoted the uptake and translocation of N, but not at a significant level. 相似文献
79.1–84.3 % of labelled N applied were recovered from the total pods including 75.3–80.4 % in labelled pods. A great part of the N was translocated in seeds, the later the labelled N application, the more proportion of N in seeds was. Application of MgSO
6.
Excised ears of Triticum durum (HD 4502 and B 449) and T. aestivum (Kalyansona and Kundan) varieties were cultured in 14 C-sucrose, and the uptake and distribution of 14 C within the ear was examined. Species-level differences in the distribution of 14 C to spikelets at basal, middle and apical positions in the wheat ear (vertical distribution) were observed. T. aestivum var. Kalyansona and Kundan showed no limitation in vertical translocation of 14 C-sucrose, whereas in T. durum there was a decrease in the distribution of 14 C to apical spikelets. Within a spikelet, the distribution of 14 C-sucrose to distal grains was significantly less than that to proximal grains in all the genotypes. 相似文献
7.
M. El.-D. Ibrahim S. Prochézka V. Borkovec 《Journal of Agronomy and Crop Science》1988,160(5):339-344
The transport and distribution of 14C- sucrose and 14C- BA were studied in internode segments with ear of two winter wheat cultivars with a different mass of kernels in the period of kernel formation. While M C-sucrose was transported and accumulated intensively in the developing ear, 14C- BA was transported much less and only a small part of it was found in the ear. With the ear development the accumulation of both 14 C-sucrose and 14 C-BA in the ear increased but the 14 C-BA distribution pattern (ratio of the internode/kernel and the rest of the ear) did not change significantly. In the period of one to two weeks after anthesis the accumulation of 14 C-sucrose and 14 C-BA was higher in the kernels of the Slavia cv., i.e. in the cultivar with a higher mass of kernels. 相似文献
8.
Nitrogen utilization and uptake patterns of wheat was studied using 15 N labelled fertilizer at four rates of application. Plants harvested at maximum tillering and at flowering indicated that plant N levels stabilized with time. Fertilizer N uptake and utilization of added fertilizer increased with time. However, uptake of soil N was not affected by rates of fertilizer at early stages. Increases were observed only at higher rates at the later harvest. 相似文献
9.
S. Ito T. Hara Y. Kawanami T. Watanabe K. Thiraporn N. Ohtake K. Sueyoshi T. Mitsui T. Fukuyama Y. Takahashi T. Sato A. Sato & T. Ohyama 《Journal of Agronomy and Crop Science》2009,195(5):368-376
Rice ( Oryza sativa cv. Koshihikari) seedlings were grown in a sandy dune soil in pots with a basal dressing of N (0.5 g N), P and K. Two N treatments were applied, a +N treatment in which a top dressing of 15 N-labeled 0.5 g N was supplied on July 20 and a −N treatment in which no additional fertilizer was supplied. During the grain-filling stage from August 6 to 13, plants were subjected to one of three temperature treatments; controlled low temperature, LT (day/night 28/23 °C), controlled high temperature, HT (35/30 °C) and uncontrolled glasshouse temperature, UT (day/night averages, 38/26 °C). All plants were then exposed to 13 CO2 for 1 h on August 11 in a growth chamber at 25 °C. On August 13, all plants were harvested and the 13 C and 15 N abundances and starch and sugar concentrations in the ears, shoots and roots were determined. The 13 C content of the ear was lower in UT than in LT irrespective of the +N or −N treatment. The translocation of 15 N to the ears was also slightly depressed in UT compared with LT. Under high-temperature conditions (HT and UT), the starch content per plant was reduced for −N, but for +N, it was not significantly different among the temperature treatments. A high accumulation of sucrose was observed in all plant parts under UT conditions. It is suggested that extreme high day temperatures during the grain-filling period may reduce starch synthesis in the grains and, especially so under N-deficient conditions. High temperatures also induce an accumulation of sucrose and a decrease in carbon and nitrogen transport from the shoots to the ears via the phloem. 相似文献
10.
Maize ( Zea mays L.) plants were grown in the field and labelled with 14 CO2 at four leaf positions from silking up to maturity. The ear leaf was the most important source of labelled photosynthates to the ear, followed by the first leaf blade above and below the ear. The movement of labelled assimilates from the second leaf blade below the ear was predominantly downwards. The ear became an important sink soon after silking and continued in importance till harvest.
Initially assimilates were partitioned within the ear as husk < cob < grains but at harvest as grains < cob < husk. There was considerable remobilization of assimilates from the husk and stem. Removal of leaves drastically altered the pattern of distribution of labelled photosynthates and the direction of movement was determined by the position of the source leaf blade and the defoliation treatment. Darkening the leaf blades did not much alter the translocation of the labelled photosynthate and increased slightly its proportion to the grains. The removal of the ear severely altered the pattern of distribution of14 C, which was mostly deposited in the stem. 相似文献
Initially assimilates were partitioned within the ear as husk < cob < grains but at harvest as grains < cob < husk. There was considerable remobilization of assimilates from the husk and stem. Removal of leaves drastically altered the pattern of distribution of labelled photosynthates and the direction of movement was determined by the position of the source leaf blade and the defoliation treatment. Darkening the leaf blades did not much alter the translocation of the labelled photosynthate and increased slightly its proportion to the grains. The removal of the ear severely altered the pattern of distribution of
11.
J. Ko&#;cielniak F. Janowiak J. Biesaga-Ko&#;cielniak 《Journal of Agronomy and Crop Science》1993,170(3):163-170
Seedlings of a maize hybrid sensitive to chilling initially grew in the growth chamber of the phytotron at 20/ 17°C (day/night) and after the formation of the fourth leaf, the soil temperature was lowered to 5°C. Under such growth conditions the dynamics of dry weight change, gas exchange and the distribution of 14 C-assimilates in seedlings were examined. The low soil temperature inhibited daily growth of dry weight of whole seedlings more than their photosynthesis. Simultaneously, it was also responsible for a greater increase in dissimilative losses.
During 37 hours (day-night-day), following exposure to14 CO2 , dissimilation in seedlings in cool soil (5°C) and in non-chilling conditions amounted to 35.1 % and 23.4 % of assimilated 14 C (AC), respectively. At lower soil temperature relatively high dissimilative losses were observed on the first day after exposure (23.5 %), lower at night (9.9 %) and the lowest on the following day - merely 1.7 % AC. Higher losses of 14 C under chilling conditions occurring on the first day were a result of limited photosynthetic refixation of 14 CO2 At night, however, they were associated with a prolonged period of intensive translocation of assimilates to the stem. It was assumed that an excessive accumulation of assimilates in leaf blades might be an additional factor responsible for increased dissimilative losses at low temperature during the first twenty-four hours. In the third period of measurements, as a result of a limited transport of 14 C, dissimilative losses were lower than in previous ones and were not dependent upon soil temperature. 相似文献
During 37 hours (day-night-day), following exposure to
12.
Influence of high temperature stress on photosynthesis and allocation of carbon into different biochemical fractions in mature leaves of Indian mustard [ Brassica juncea (L) Czern] was investigated. Heat stress reduced 14 CO2 fixation and inhibited the translocation of carbon from the leaves. Allocation of 14 C into starch and residue fractions was significantly lower in heat stressed plant leaves. Starch content was significantly reduced in heat stressed plants. 相似文献
13.
Effect of plant growth regulators Naphthalene acetic acid (NAA), Gibberellic acid (GA3 ) and Kinetin on 14 CO2 assimilation, partitioning of 14 C into major biochemical fractions and translocation of assimilates was studied in different parts of Indian Mustard ( Brassica juncea ) at late ripening stage. Leaves, stem and pod walls are photosynthetically active and are important sources for seed filling. NAA and kinetin increased the 14 CO2 assimilation rate in all the three photosynthetically active parts. All the three growth regulators increased the export of 14 assimilates out of source organs and increased the movement of assimilates into the reproductive parts (pods). The increased movement of photoassimilates into the developing pods may be due to the stimulation of sink activity by the growth regulators which resulted in the higher demand for photoassimilates. It was suggested that growth regulators may increase yield by altering distribution of assimilates in the mustard plants. 相似文献
14.
Nitrogen transportation from different organs was investigated by labelling pods, leaves and internodes of upper stem with 15 N-urea during flowering. Labelled plants were harvested one month after flowering and determined the amount of 15 N in relative parts. The results of the experiment show the directions of 15 N applied in different organs during flowering. Transportation of 15 N applied in pods of lower terminal of the main stem and first branch was mainly directed to seeds inside the labelled pods, about 17 % of 15 N entered into seeds 7 days after last labelling, a little transportation each other between the branch and terminal was found, more than 80 % of 15 N applied on leaves during flowering was transported out of the leaves after flowering, 35 % and 67.93 % on average was translocated in pods for early and late flowering, respectively, while 55.97 % of 15 N applied on surface of internodes of upper stem below terminal was found in pods. It was corroborated that nitrogen transportation also occurs within pods by labelling different parts of pods, much greater amount of nitrogen was transported from lower part to upper part of pods than those in opposite direction. 相似文献
15.
The role of leaves, stem and reproductive parts in 14 CO2 fixation and subsequent photosynthate translocation was studied in Indian mustard ( Brassica juncea L.) at three growth stages. The data indicated that leaves, stem and pods are important sources of photosynthates for seed filling. At bud emergence stage leaves are the principle site of 14 CO2 , fixation. The contribution of leaves declines at subsequent stages, where as the contribution of pod walls increased from bud emergence stage to ripening stage. The contribution of the stem remains more or less constant at all three growth stages studied. Although stem can fix 14 CO2 , at bud emergence and flowering stages it imported 14 C-photosynthates from leaves. However, stem exported photosynthates during subsequent growth stages. 相似文献
16.
17.
Effect of heat stress on 14 CO2 assimilation and translocation by different parts was investigated in Indian mustard ( Brassica juncea (L.) Czern.]. Heat stress reduced 14 CO2 assimilation by leaves, stem and pods. Export of radioactive carbon from upper and lower leaves, upper and lower stem and stem of terminal raceme was inhibited in response to heat stress. Import of 14 C-photosynthates into pods was also inhibited by heat stress indicating reduction in sink strength of the developing pods. 相似文献
18.
Field bean planes cultivar Nadwiślański were submitted to soil drought (30 % of field soil water capacity) for 5 days at the stage of pod formation (A) and of rapid pod growth (B) and then exposed for 20 minutes to 14 CO2 . Radioactivity of leaves, stems, roots, and pods or pod shells and seeds was measured 1, 5, 24 and 48 hours after exposition.
In both stages soil drought reduced by about five times total CO2 assimilation, mainly owing to lower activity of the photosynthetic apparatus and also, though less so, to reduced leaf growth. Photosynthetic activity referred to the dry weight of the leaves dropped to 22-35% of controls. Accumulation of photosynthetates in generative organs was much less depressed than 14 CO2 assimilation. 48 hours after exposition to 14 CO2 of drought treated plants, the contents of 14 C of pods in phase A, and seeds in phase B, amounted to respectively 24% and 36% of assimilated 14 C and equalled 91.5% and 74% of the corresponding values for controls.
The progressive decline of radioactivity in leaves and stems after14 CO2 exposition was distinctly correlated to the rise of radioactivity of generative organs both in soil drought treated plants and in controls. Slightly lower values of correlation coefficients in drought treated plants may indicate impairment under drought conditions of synchronization in processes of unloading and accumulation of assimilates.
In plants drought treated in phase A the ability to dissimilate14 C was reduced to about 59% of that in controls, but when drought was applied in phase B, dissimilation rate was about three times as high. 相似文献
In both stages soil drought reduced by about five times total CO
The progressive decline of radioactivity in leaves and stems after
In plants drought treated in phase A the ability to dissimilate
19.
Four types of cattle manure were prepared by mixing faeces with different ratios of urine + straw, one manure being faeces without straw and urine. Following 3 to 6 months of storage, the manures were applied in spring or autumn to a sandy loam and a coarse sand in amounts corresponding to 120 kg N ha−1. Spring barley (Hordeum vulgare L.) undersown with perennial ryegrass (Lolium perenne L.) were used as test crops. Barley was harvested at maturity and the wintering ryegrass was cut three times in the second year. Additional mineral N in the form of 15N-labelled mineral fertilizer (50 kg N ha−1) was added to all barley plots at planting in spring. Non-manured plots receiving only the 15N-labelled mineral fertilizer were included. Faeces without urine + straw contained more NH4-N than the other manures and spring incorporation of this manure gave the highest dry matter yield and N uptake of the barley. When faeces without urine + straw was applied in autumn, the yield and N uptake were increased only on the sandy loam. On the coarse sand, the NH4-N was probably leached as NO3-N during the winter. The three manures with urine + straw did not affect barley grain yield or total N uptake. Thus these manures did not mineralize nor immobilize measurable quantities of N in the first growth period. On the sandy loam, the patterns of N uptake in ryegrass indicated an increased availability of manure N during the second growth period. The availability of N from the 15NH415NO3 was similar in all plots when manures were applied in spring. Less 15N was taken up by the spring barley when manure was added in autumn compared with crops given 15NH415NO3 only. Thus short-term effects of N in cattle faeces stored with or without straw + urine are low. For soils low in mineral N such manures may potentially reduce crop N uptake. 相似文献
20.
Zhang Qinzheng Lan Xiafua Xi Haifu Zhu Xuequn Liu Yinhua 《Journal of Agronomy and Crop Science》1991,166(2):96-100
The conversion of SO2- 4 -S and changes in content of S in various constituents in leaves of rape seedlings transplanted were investigated by using (NH4 )2 35 SO4 as a tracer to exploit formation and accumulation of glucosinolates in oilseed rape. Seedlings grown under sandy culture absorbed 35 SO2- 4 which was added to the cultural solution and incorporated into amino acids, glucosinolates and proteins rapidly. Distribution of extractable 35 S with 70 % methanol in glucosinolates in leaves declined with time from labelling, while those in amino acids rised correspondingly. Per cents of 35 S incorporated into bound form in total 35 S increased linearly and those of 35 S into glucosinolates and amino acids decreased with time within five days from labelling. After that the relative amounts of 3S S in three constituents was basically constant. Content on dry weight basis of labelled glucosinolates and amino acids expressed as μmol S/g.d.w. increased linearly with time from labelling with absorption of 35 SO2- 4 from soil by the seedlings under soil culture. Compared with seedlings grown under sandy culture, more 35 S was incorporated into glucosinolates in leaves of seedlings grown under soil culture. 相似文献