Diurnal regulation of rice N uptake ability under interrupted N supply

To elucidate changes in the defensive traits of tree seedlings under global environmental changes, we evaluated foliar defensive traits of the seedlings of successional trees, such as beech, oak, and magnolia grown in a natural-light phytotron. Potted seedlings were grown under the combination of two CO2 concentrations (360 vs. 720 ppm) and two nitrogen (N) treatments (4 vs. 15 kg N ha−1 yr−1) for two growing seasons using quantitative chemical analyses and anatomical method. We hypothesized that the effects of CO2 and N depend on the successional type, with late successional species providing greater defense of their leaves against herbivores, as this species exhibits determinate growth. Beech, a late successional species, responded the most to both elevated CO2 concentration (eCO2) and high N treatment. eCO2 and low N supply enhanced the defensive traits, such as the high leaf mass per area (LMA), high carbon to N ratio (C/N ratio), and increase in the concentrations of total phenolic and condensed tannin in agreement with the carbon–nutrient balance (CNB) hypothesis. High N supply decreased the C/N ratio due to the high N uptake in beech leaves. Oak, a mid–late successional species, exhibited different responses from beech: eCO2 enhanced the LMA, C/N ratio, and concentration of total phenolics of oak leaves, but only condensed tannin increased under high N supply. Magnolia did not respond to all treatments. No interactive effects were observed between CO2 and N supply in all species, except for the concentration of total phenolics in oak. Although the amounts of phenolic compounds in beech and oak varied under eCO2 and high N treatments, the distribution of these compounds did not change. Our results indicate that the changes in the defensive traits of forest tree species under eCO2 with N loading are related to the successional type.

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Bioassay of forest floor nitrogen supply for plant growth

Canadian Journal of Forest Research ◽

10.1139/x86-233 ◽

1986 ◽

Vol 16 (6) ◽

pp. 1320-1326 ◽

Cited By ~ 14

Author(s):

K. Van Cleve ◽

O. W. Heal ◽

D. Roberts

Keyword(s):

Forest Floor ◽

Black Spruce ◽

Nitrogen Concentration ◽

N Uptake ◽

Mineral Soil ◽

Forest Types ◽

N Supply ◽

Paper Birch ◽

Forest Floors ◽

P Supply

Using a bioassay approach, this paper considers the nitrogen-supplying power of forest floors from examples of the major forest types in interior Alaska. Yield and net N uptake by paper birch seedlings grown in standardized mixtures of quartz sand and forest floor organic matter, and separate incubation estimates of N mineralization and nitrification for the forest floors, were employed to evaluate potential N supply. Black spruce and floodplain white spruce forest floors supplied only one-fifth the amount of N taken up by seedlings growing in other forest floors. Incubation estimates showed these forest floors yielded 4 and 15 times less extractable N, respectively, than the more fertile birch forest floors. In comparison with earlier estimates of P supply from these same forest floors, the upland types showed greater deficiency of N whereas floodplain types showed greater deficiency of P in control of seedling yield. The latter condition is attributed to the highly calcareous nature of the floodplain mineral soil, the consequent potential for P fixation, and hence greater potential deficiency of the element compared with N in mineralizing forest floors. Nitrogen concentration of the forest floors was the best predictor of bioassay response.

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N uptake, N partitioning, and photosynthetic N-use efficiency of an old and a new maize hybrid

Canadian Journal of Plant Science ◽

10.4141/cjps94-088 ◽

1994 ◽

Vol 74 (3) ◽

pp. 479-484 ◽

Cited By ~ 35

Author(s):

D. E. McCullough ◽

A. Aguilera ◽

M. Tollenaar

Keyword(s):

Dry Matter ◽

N Uptake ◽

N Use Efficiency ◽

Maize Hybrid ◽

Unit Leaf ◽

N Supply ◽

N Partitioning ◽

Use Efficiency ◽

N Use ◽

Leaf N

An old maize (Zea mays L.) hybrid (Pride 5) has been shown to be less tolerant to N stress than a new maize hybrid (Pioneer 3902) during early phases of development. The objective of this study was to quantify the response of the two hybids to N supply in terms of N uptake, N partitioning, and photosynthetic N–use efficiency. Plants were grown under controlled-environment conditions until the 12-leaf stage at three levels of N supply (i.e., 15 mM N, 2.5 mM N, and 0.5 mM N) and were sampled at the 4-, 8-, and 12-leaf stages. Rates of N uptake per unit ground area were higher for Pioneer 3902 than for Pride 5 under maximum N stress during the 8- to 12-leaf phase, but rates were higher for Pride 5 at high N. Rates of N uptake per unit root weight were higher for Pioneer 3902 than for Pride 5 under both medium and low N supply. The old hybrid (Pride 5) partitioned more dry matter and N to leaves than the new hybrid under low N supply, but leaf N per unit leaf area was higher for the new hybrid. The new hybrid (Pioneer 3902) maintained greater rates of leaf photosynthesis per unit leaf N regardless of N supply. Consequently, results indicate that the higher N-use efficiency of Pioneer 3902 under low N supply is associated with higher N uptake and a higher leaf N per unit leaf area. Key words:Zea mays L., dry matter accumulation, photosynthesis, leaf N

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The Influence of Nitrogen on the Elevated CO2 Response in Field-Grown Rice

Functional Plant Biology ◽

10.1071/pp9960045 ◽

1996 ◽

Vol 23 (1) ◽

pp. 45 ◽

Cited By ~ 48

Author(s):

LH Ziska ◽

W Weerakoon ◽

OS Namuco ◽

R Pamplona

Keyword(s):

Elevated Co2 ◽

Growth Response ◽

Oryza Sativa L ◽

N Uptake ◽

Root Production ◽

N Availability ◽

Above Ground Biomass ◽

Co2 Response ◽

Ground Biomass ◽

N Supply

Rice (Oryza sativa L. cv. IR72) was grown in the tropics at ambient (345 μL L-1) or twice ambient (elevated, 700 μL L-1) CO2, concentration at three levels of supplemental nitrogen (N) (no additional N (N0), 90 kg ha-1 (N1) and 200 kg ha-1 (N2)) in open-top chambers under irrigated field conditions from seeding until flowering. The primary objective of the study was to determine if N supply alters the sensitivity of growth and photosynthesis of field-grown rice to enriched CO2. A second objective was to determine the influence of elevated CO2 on N uptake and tissue concentrations. Although photosynthesis was initially stimulated at the leaf and canopy level with elevated CO2 regardless of supplemental N supply, with time the photosynthetic response became highly dependent on the level of supplemental N, increasing proportionally as N availability increased. Similarly, a synergistic effect was noted between CO2 and N with respect to above-ground biomass with no effect of elevated CO2 observed for the No treatment. Most of the increase in above-ground biomass with increasing CO2 and N was associated with increased tiller and, to a lesser extent, root production. The concentration of above-ground N decreased at elevated CO2 regardless of N treatment; however, total above-ground N did not change for the N1 and N2 treatments because of the greater amount of biomass associated with elevated CO2. For rice, the photosynthetic and growth response to elevated CO2 may be highly dependent on the supply of N. If additional CO2 is given and N is not available, lack of sinks for excess carbon (e.g. tillers) may limit the photosynthetic and growth response.

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The Response of Grain Yield and Root Morphological and Physiological Traits to Nitrogen Levels in Paddy Rice

Frontiers in Plant Science ◽

10.3389/fpls.2021.713814 ◽

2021 ◽

Vol 12 ◽

Author(s):

Wei Xin ◽

Hualong Liu ◽

Hongwei Zhao ◽

Jingguo Wang ◽

Hongliang Zheng ◽

...

Keyword(s):

Grain Yield ◽

Surface Area ◽

N Uptake ◽

Growth Stages ◽

N Accumulation ◽

Oxidation Activity ◽

Cytokinin Content ◽

N Supply ◽

Yield Formation ◽

Late Growth

Rice (Oryza sativa L.) is an important crop in China. Although it is known that its yield is restricted by nitrogen (N) supply, the response of the root system to N supply specifically has not been systematically explored. This study aimed to investigate the effect of N uptake on grain yield to clarify the relationships between root morphophysiological traits and N uptake, and to understand relation between phytohormones and root morphophysiological traits. Two N-efficient absorption cultivars (NEAs) and two N-inefficient absorption cultivars (NIAs) were grown in the field, and three N conditions, deficient N (60 kg ha–1), intermediate N (180 kg ha–1), and sufficient N (240 kg ha–1), were applied during the growing season. The results showed higher dry matter and grain yield in NEAs than in NIAs, which was mainly attributed to increased N uptake in the mid- and late growth stages under all N conditions. And NEAs have different root regulation methods to obtain higher N accumulation and yield under different N supply conditions. Under lower N conditions, compared with NIAs, NEAs shown greater total root length, root oxidation activity, and root active absorbing surface area and smaller root diameter owing to higher indole-3-acetic acid and cytokinin content and lower 1-aminocyclopropane-1-carboxylic acid content in the early growth stages to respond to low N stress faster, laying a morphophysiological basis for its high N-uptake capacity in the mid- and late growth stages. Under higher N conditions, NEAs had higher root oxidation activity and root active absorbing surface area for N uptake and yield formation owing to higher abscisic acid and cytokinin content in the mid- and late growth stages, which improved the seed setting rate, thereby increasing the rice grain yield. These results suggest that NEAs can optimize the morphophysiological characteristics of roots through phytohormone regulation to adapt to different nutrient conditions, thereby promoting N accumulation and yield formation in rice.

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How Nitrogen Supply Affects Growth and Nitrogen Uptake, Use Efficiency, and Loss from Citrus Seedlings

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.1.105 ◽

1996 ◽

Vol 121 (1) ◽

pp. 105-114 ◽

Cited By ~ 14

Author(s):

John D. Lea-Cox ◽

James P. Syvertsen

Keyword(s):

Plant Growth ◽

N Uptake ◽

Single Application ◽

N Application ◽

N Supply ◽

N Concentration ◽

Leaf N Concentration ◽

Use Efficiency ◽

Complete Nutrient Solution ◽

Leaf N

We examined how N supply affected plant growth and N uptake, allocation and leaching losses from a fine sandy soil with four Citrus rootstock species. Seedlings of `Cleopatra' mandarin (Citrus reticulata Blanco) and `Swingle' citrumelo (C. paradisi × P. trifoliata) were grown in a glasshouse in 2.3-liter pots of Candler fine sand and fertilized weekly with a complete nutrient solution containing 200 mg N/liter (20 mg N/week). A single application of 15NH415NO3(17.8% atom excess 15N) was substituted for a normal weekly N application when the seedlings were 22 weeks old (day O). Six replicate plants of each species were harvested at 0.5, 1.5, 3.5, 7, 11, and 30 days after 15N application. In a second experiment, NH4 NO3 was supplied at 18,53, and 105 mg N/week to 14-week-old `Volkamer' lemon (C. volkameriana Ten. & Pasq.) and sour orange (C. aurantium L.) seedlings in a complete nutrient solution for 8 weeks. A single application of 15NH415NO3 (23.0% 15N) was substituted at 22 weeks (day 0), as in the first experiment, and seedlings harvested 3,7, and 31 days after 15N application. Nitrogen uptake and partitioning were similar among species within each rate, but were strongly influenced by total N supply and the N demand by new growth. There was no 15N retranslocation to new tissue at the highest (105 mg N/week) rate, but N supplies below this rate limited plant growth without short-term 15N reallocation from other tissues. Leaf N concentration increased linearly with N supply up to the highest rate, while leaf chlorophyll concentration did not increase above that at 53 mg N/week. Photosynthetic CO2 assimilation was not limited by N in this study; leaf N concentration exceeded 100 mmol·m-2 in all treatments. Thus, differences in net productivity at the higher N rates appeared to be a function of increased leaf area, but not of leaf N concentration. Hence, N use efficiency decreased significantly over the range of N supply, whether expressed either on a gas-exchange or dry weight basis. Mean plant 15N uptake efficiencies after 31 days decreased from 60% to 47% of the 15N applied at the 18,20, and 53 mg N/week rates to less than 33% at the 105 mg N/week rate. Leaching losses increased with N rate, with plant growth rates and the subsequent N requirements of these Citrus species interacting with residual soil N and potential leaching loss.

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Nitrogen Fertilization of Plants Irrigated with Desalinated Water: A Study of Interactions of Nitrogen with Chloride

Water ◽

10.3390/w12092354 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2354

Author(s):

Asher Bar-Tal ◽

Escain Kiwonde ◽

Beeri Kanner ◽

Ido Nitsan ◽

Raneen Shawahna ◽

...

Keyword(s):

Nitrogen Fertilization ◽

N Uptake ◽

N Fertilization ◽

High Yield ◽

N Leaching ◽

Plant Tissues ◽

Desalinated Water ◽

N Supply ◽

Wide Range ◽

High Yields

The overall aim of this research was to optimize nitrogen (N) fertilization of plants under desalinated water and a wide range of chloride concentrations for high yield while minimizing downward leaching of nitrate and chloride. The response of two crops, lettuce and potato, to N concentration (CN) in the irrigating solution using desalinated and wide range of Cl concentrations (CCL) was evaluated. The yields of both crops increased with N up to optimal CN of the irrigating solution and decreased as CCL increased. Optimal CN in both crops was higher in the desalinated water than high CCL treatments. N uptake by plants increased with CN in the irrigating solution and the highest uptake was at low CCL. As expected, N fertilization suppressed Cl accumulation in plant tissues. Drainage of N and Cl increased with increase in CCL in the irrigating solution and N fertilization above optimal CN resulted in steep rise in downward N leaching. The overall conclusion is that as water quality is improved through desalination, higher N supply is required for high yields with less groundwater pollution by downward leaching of N and Cl.

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Root and nitrate-N distribution and optimization of N input in winter wheat

Scientific Reports ◽

10.1038/s41598-019-54641-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Bin-Bin Guo ◽

Bei-Cheng Liu ◽

Li He ◽

Yang-Yang Wang ◽

Wei Feng ◽

...

Keyword(s):

Winter Wheat ◽

Root System ◽

N Uptake ◽

Root Weight ◽

N Application ◽

Weight Density ◽

N Supply ◽

Nitrate N ◽

N Input ◽

Root Weight Density

AbstractScientific management of nitrogen (N) fertilizer has a significant effect on yield while also reducing the environmental risks. In this study, we conducted field experiments over three years at two different sites (Zhengzhou and Shangshui) in Henan Province, China, using different N application rates (0, 90,180, 270, and 360 kg ha−1) to determine the relationships between soil N supply and N demand in winter wheat (Triticum aestivum L.). Optimal N input was then determined. Both sites showed the same trend. Namely, aboveground N uptake and soil nitrate N (NO3−-N) increased with increasing N, while NO3−-N decreased with increasing soil depth, gradually moving downwards with growth. A significant correlation (p < 0.001) between increasing aboveground N uptake and increasing NO3−-N was also observed under N application, with the best relationships occurring in the 20–60 cm layer during jointing-anthesis (R2 = 0.402–0.431) and the 20–80 cm layer at maturity (R2 = 0.474). Root weight density showed the same spatial-temporal characteristics as NO3−-N, following a unimodal trend with increasing N, and peaking at 90 kg ha−1. The root weight density was mainly distributed in the 0–60 cm layer (above 80%), with the 20–60 cm layer accounting for 30% of the total root system. In this layer, the root weight density was also significantly positively correlated with aboveground N uptake. Wheat yield reached saturation under high N (>270 kg ha−1), with a sharp decrease in N use efficiency (NUE) and linear increase in residual NO3−-N. To balance yield and the risk of environmental pollution in the experimental area, an N application rate of 180–270 kg ha−1 is recommended under sufficient irrigation, thereby supporting a well-developed root system while ensuring balance between N supply and demand.

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Phosphorus nutrition of spring wheat (Triticum aestivum L.). 3. Part 2, Aust. J. Agric. Res., 1997, 48, 869-81.. Effects of plant nitrogen status and genotype on the calibration of plant tests for diagnosing phosphorus d

Australian Journal of Agricultural Research ◽

10.1071/a96161 ◽

1997 ◽

Vol 48 (6) ◽

pp. 883 ◽

Cited By ~ 8

Author(s):

D. E. Elliott ◽

D. J. Reuter ◽

G. D. Reddy ◽

R. J. Abbott

Keyword(s):

Vegetative Growth ◽

N Uptake ◽

Physiological Age ◽

Root Yield ◽

P Deficiency ◽

Plant Nitrogen ◽

N Supply ◽

P Concentration ◽

Labile P ◽

N Status

The influence of plant nitrogen (N) status and plant genotype on plant test criteria for diagnosing phosphorus (P) deficiency in wheat was examined in 2 glasshouse experiments. Criteria for both total and labile P in leaf blades of standard physiological age are, to only a minor extent, affected by variations in N supply and by genotypic diversity Interactions between N and P supply had marked and complex effects on shoot and root yield, P and N uptake in shoots and concentrations in leaf blades, and on the distribution of P and P fractions within wheat shoots. Thus, whilst the external P requirement (i.e. P level required for 90% maximum shoot yield) more than doubled as N supply was raised, variations in N supply had only minor effects on internalP requirement (i.e. the tissue P concentration required for 90% maximum shoot yield). On the other hand, the external P requirement for root yield varied markedly with plant age and N supply. N deficiency increased total P concentrations in leaf blades at all P levels, primarily by increasing the concentration of the labile P fraction. Also, N concentrations increased to adequate levels in the shoots of P-deficient plants but only at the 2 lower levels of applied N. Plant N status also affected the shape of diagnostic relationships between relative shoot yield and P concentrations in young and mature leaf blades by constricting P concentration in the adequate-luxury zone and increasing the slope of the relationship in the zone of deficiency. Whilst the asymptotic grain yield and external requirement for P for the tall cultivar (Halberd) was substantially less than for the semi-dwarf cultivars (Condor and Durati), consistent P cultivar interactions on shoot yield and P uptake during vegetative growth, were largely absent. For leaf blade classes examined, the shape of the diagnostic relationship for total and labile P was essentially similar for each cultivar. As a result, differences in estimated critical P concentrations for total and labile P between the cultivars for leaf blades during vegetative growth, or criteria for grain, glumes, and straw at maturity, were relatively small.

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Film-mulched maize production: response to controlled-release urea fertilization

The Journal of Agricultural Science ◽

10.1017/s002185961700048x ◽

2017 ◽

Vol 155 (8) ◽

pp. 1299-1310 ◽

Cited By ~ 5

Author(s):

J. M. GUO ◽

J. Q. XUE ◽

A. D. BLAYLOCK ◽

Z. L. CUI ◽

X. P. CHEN

Keyword(s):

Controlled Release ◽

Production Systems ◽

Supply And Demand ◽

N Uptake ◽

N Fertilization ◽

N Recovery ◽

N Losses ◽

Maize Production ◽

N Supply ◽

Controlled Release Urea

SUMMARYOptimal nitrogen (N) management for maize in the film-mulched production systems that are widely used in dryland agriculture is difficult because top-dressing N is impractical. The current research determined how matching N supply and demand was achieved before and after silking stages, when single applications of controlled release urea (CRU) were combined with conventional urea in film-mulched maize production. The CRU: urea mixture was applied in a 1 : 2 or 2 : 1 ratio and all three fertilizer regimes (urea alone and CRU: urea at 1 : 2 or 2 : 1) were applied at N rates of 180 and 240 kg/ha over 2 years. The 1 : 2 CRU: urea mixture, applied once at 180 kg N/ha, was found to synchronize N supply with demand, thereby reducing N losses. The highest grain yields (11·8–12·0 t/ha), N uptake (232–239 kg/ha), N recovery (65·8–67·7%) and high net economic return were achieved with this regime. These results indicate that a single application of a mixture of CRU and urea can synchronize N supply with demand and provide higher yields and profits than conventional N fertilization in film-mulched maize systems.

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