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1.
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
2.
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
3.
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
4.
Zhang Qinzheng Xi Haifu Lan Xiafua Zhu Xuequn Liu Yinhua 《Journal of Agronomy and Crop Science》1991,166(3):152-156
Rape plants were labelled by applying (NH4 )2 35 SO4 to soil. Changes in content of 35 S in various constituents in pods and grains were determined during siliquae development to exploit formation and accumulation of glucosinolates in oilseed rape. Content of 35 S in glucosinolates expressed as μmol S/g.d.w. and its relative amounts in extractable forms in young siliquae were in constant level within one week after flowering, but either absolute content or relative content of 35 S in glucosinolates increased largely by two weeks after flowering, thereafter the distribution of extractable 35 S in glucosinolates of siliquae and grains increased linearly as proceeding of its development, 35 S in extracts of grains almost was in form of glucosinolates after 8 weeks from flowering. Amounts of both 35 S in glucosinolates and dry matter per pod increased linearly with time after flowering. According to the changes of amounts of 35 S in other constituents per pod, it could be supposed that glucosinolates accumulated in seeds might be transported from other organs together with nutrients. 相似文献
5.
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
6.
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
7.
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
8.
V. Borkovec S. Procházka M. El.-D. Ibrahim 《Journal of Agronomy and Crop Science》1990,165(4):217-223
A lysimeter trial is described in which the fate of 15 N was monitored in a sand, loam and clay soil by using it over a period of 6 years. The following results were obtained.
1. The uptake of fertilizer nitrogen by plants, determined by using15 N, is lower than by using the conventional method ("difference method"). Nitrate 15 N is better utilized by the plants than is ammonium 15 N. The total nitrogen uptake only gives hints of these differences.
2. The extent to which plants utilize fertilizer15 N is between 38 and 58%; in the case of the method of differences this figure is between 48 and 68%.
3. Plants remove more nitrogen from the soil when fertilizer N is applied than when without fertilization. The influence of these two nutrient forms is of subordinate significance.
4. After a trial period of six years between 26 and 54 % of the fertilizer15 N remains in the soil. The resulting sequences are clay > loam > sand > and ammonium > nitrate.
5. The immobilization of the fertilizer15 N is most pronounced in the first four years but then decreased considerably; in the case of the sandy soil it is then even slightly regressive.
6. The biggest part of the15 N is deposited in the uppermost layer of the soil. The amount of 15 N in the deeper layers is diminished appreciably. The type of soil has a greater influence than the form of nitrogen.
7. If the amount of fertilizer N left in the soil is compared with the N losses from the soil's reservoir (plants' uptake, leaching) there is a negative balance for the soil nitrogen which mainly is determined by the type of soil. 相似文献
1. The uptake of fertilizer nitrogen by plants, determined by using
2. The extent to which plants utilize fertilizer
3. Plants remove more nitrogen from the soil when fertilizer N is applied than when without fertilization. The influence of these two nutrient forms is of subordinate significance.
4. After a trial period of six years between 26 and 54 % of the fertilizer
5. The immobilization of the fertilizer
6. The biggest part of the
7. If the amount of fertilizer N left in the soil is compared with the N losses from the soil's reservoir (plants' uptake, leaching) there is a negative balance for the soil nitrogen which mainly is determined by the type of soil. 相似文献
9.
Investigations about the distribution of assimilates during flowering in broad beans ( Vicia faba L.)
The distribution of assimilates during flowering was studied on single plants exposed to14 CO2 in the field. The plants were harvested 1, 3, 15 days after exposition and at ripening. Results:
1. At the begin of flowering the nodes with flowers assimilated much14 C with a tendency of higher contents in the more above situated nodes. The concentration of 14 C was similar in blades, stalks and flowers.
2. The assimilates incorporated after 24 hours were only to a small amount translocated afterwards. Only 3 % went to the apical region. An intensive restorement out of the blades took place at the time of ripening.
3. In the midst of flowering the concentration of14 C was lower in the nodes with open flowers than in those with shut or with pods. At that time pods are already strong sinks that withdraw assimilates from blades and stalks.
4. At the time when large and small pods are growing on the lower and middle nodes, the nodes in the apical region will be deprived of assimilates (effects of dominance).
5. Roots and nodules had low but stable contents and concentrations of14 C during flowering. These descended distinctly at ripening. 相似文献
The distribution of assimilates during flowering was studied on single plants exposed to
1. At the begin of flowering the nodes with flowers assimilated much
2. The assimilates incorporated after 24 hours were only to a small amount translocated afterwards. Only 3 % went to the apical region. An intensive restorement out of the blades took place at the time of ripening.
3. In the midst of flowering the concentration of
4. At the time when large and small pods are growing on the lower and middle nodes, the nodes in the apical region will be deprived of assimilates (effects of dominance).
5. Roots and nodules had low but stable contents and concentrations of
10.
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
11.
Soybean ( Glycine max L.) nitrogen nutrition is ensured by both symbiotic nitrogen fixation and mineral nitrogen assimilation. The relationship between these two modes of N nutrition was analysed in 3 growth types (determinate, semi-determinate and undeterminate) of soybean. The nitrate reductase activity and nitrogenase activity (acetylene reduction) of plants grown in the field and greenhouse showed that these enzymatic activity acted simultaneously or successively during the growth cycle, depending on the availability of inorganic nitrogen in the growing medium. Undeterminate soybean types had a higher potential nitrate reductase activities than determinate types.
The proportion of N2 fixed as measured by 15 N labelling or stem ureide content indicated that determinate soybeans derived a higher proportion of their N from N2 fixation than the undeterminates. 相似文献
The proportion of N
12.
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
13.
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
14.
Response of sunflower ( Helianthus annuus L.) to sulphur applied ca. 0, 30, 90 and 150 mg kg-1 and nitrogen applied ca. 0, 100 and 200 mg kg-1 soil were studied on a Typic Camborthids in greenhouse. Nitrogen and S application had a significant (P < 0.01) main and interactive effect on seed yield and dry weight of leaves and stem. Cumulative N and S contents of sunflower seeds, stem and leaves were significantly (P < 0.01) affected by N and S application. Sulphur transport and accumulation in sunflower seeds was increased with S application. There were significant (P < 0.01) correlations between seed yield and N and S content of sunflower plants. Critical S concentration (%) in 60 days old plants was 0.36 for 95 % relative yield of the maximum. Application of 90 mg S kg-1 with 200 mg N kg-1 resulted in the highest seed yield and maximum total S and N contents in sunflower leaves, stem and seeds. Relative increase in sunflower seeds yield at higher levels of N and S was more than that of dry weight of stem and leaves. 相似文献
15.
16.
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
17.
Little is known about the effect of fertilization on the N uptake of sunflowers. A 42 factorial trial with 0, 60, 120 and 180 kg N ha−1 and 0, 15, 30 and 45 kg P ha−1 was conducted over three years. The N content and concentration of leaves, stems and capitula were determined at three growth stages. High N levels increased the N content and concentration of all plant parts at all growth stages sharply. High P levels increased the N content of all plant components through better growth. P has an inconsistent effect on N concentration but tended to decrease it. After flowering the crop assimilated 20 to 25 % of the total N. This implies that N applied can still be applied and utilized by the crop at a late stage. This should be substantiated by further research. 相似文献
18.
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
19.
Genotypic differences in the translocation of temporarily stored 14 C from the stem to the grains in spring wheat (Triticum aestivum L.)
In three field experiments with two spring wheat genotypes (Kolibri and breeding line 93117 ), changes in the total nonstructural carbohydrates (TNC) of the stem were observed after anthesis. Maximum values were measured in the third or fourth week following anthesis when stems contained 300 to 400 mg TNC. Thereafter TNC content declined up to maturity.
Flag leaves of individual shoots or all plants in micro-plots were labelled with14 C 5 days prior to anthesis, at anthesis or 5 days after anthesis to observe long term movements of assimilates during grain filling. After a chase period of two to three days, 60 to 80 % of total 14 C recovered in the shoot was in the stem. From total l4 C recovered two to three days after labelling, Kolibri had translocated 12.5 to 27.0 % into the grains by maturity whereas this portion was significantly higher for the breeding line 93117 (22.5 to 43.9 %). It was concluded that genotypes differ in the translocation of soluble carbohydrates from the stem to the grains. These differences were not related to parameters describing the 'source-sink' relationship, such as leaf area, grain number or grain size. However, the lower translocation rates of Kolibri coincided with a lower TNC concentration in the stem dry matter. This was due to a higher stem weight at anthesis, a longer period of stem elongation and a higher incorporation of assimilates into structural carbohydrates in non elongating stem parts after anthesis. It was therefore suggested that the accumulation of TNC in the stem and the remobilisation of these reserves for grain filling are determined partly by factors related to the carbohydrate metabolism in the stem. 相似文献
In three field experiments with two spring wheat genotypes (Kolibri and breeding line 93117 ), changes in the total nonstructural carbohydrates (TNC) of the stem were observed after anthesis. Maximum values were measured in the third or fourth week following anthesis when stems contained 300 to 400 mg TNC. Thereafter TNC content declined up to maturity.
Flag leaves of individual shoots or all plants in micro-plots were labelled with
20.
H. Bergmann H. Eckert C. Weber und D. Roth 《Journal of Agronomy and Crop Science》1991,166(2):117-126
Effect of monoethanolamine on yield of crops
I. Studies on the effect of monoethanolamine on the grain yield and the nitrogen household in cereal plants (pot experiments)
The effect of monoethanolamine (EA, applied as foliar spray, 10 mg per pot) on grain yield and yield components was investigated in pot experiments with spring barley, winter wheat, and winter rye. Under conditions of a moderate drought stress the applied EA increased the grain yield of spring barley from 5 % to 7 % (significance only at α= 0.05). A stimulating effect of EA on the grain yield of winter wheat and winter rye was also obtained.
The positive influence of EA on the grain yield of spring barley was reproducible under the conditions of a limited water supply in small-scale plot experiments (increase of yield about 9 %).
In case of spring barley and winter rye the increase of the grain yield by EA, applied at growth stage 31 (= DC 31) was connected with a greater number of ear-bearing tillers. The increase of the winter wheat yield resulted from more grains per ear of the tillers.
The enhanced formation of tiller grain mass and total tiller biomass by EA was in correlation with a higher nitrogen import into tillers (r = 0.8+ ). Since an export of N from the main shoots into the tillers was not observed a higher N uptake (≥ 6 %) was calculated from N balances. After a fertilization with 15 N-labelled fertilizers the additional 15 N uptake was 13 % to 20 %.
Possible stress reducing activities caused by EA are discussed. 相似文献
I. Studies on the effect of monoethanolamine on the grain yield and the nitrogen household in cereal plants (pot experiments)
The effect of monoethanolamine (EA, applied as foliar spray, 10 mg per pot) on grain yield and yield components was investigated in pot experiments with spring barley, winter wheat, and winter rye. Under conditions of a moderate drought stress the applied EA increased the grain yield of spring barley from 5 % to 7 % (significance only at α= 0.05). A stimulating effect of EA on the grain yield of winter wheat and winter rye was also obtained.
The positive influence of EA on the grain yield of spring barley was reproducible under the conditions of a limited water supply in small-scale plot experiments (increase of yield about 9 %).
In case of spring barley and winter rye the increase of the grain yield by EA, applied at growth stage 31 (= DC 31) was connected with a greater number of ear-bearing tillers. The increase of the winter wheat yield resulted from more grains per ear of the tillers.
The enhanced formation of tiller grain mass and total tiller biomass by EA was in correlation with a higher nitrogen import into tillers (r = 0.8
Possible stress reducing activities caused by EA are discussed. 相似文献