scholarly journals INFLUENCE OF BIOCIDES ON NITRIFICATION, DENITRIFICATION, AND TOMATO N UPTAKE

HortScience ◽  
1991 ◽  
Vol 26 (6) ◽  
pp. 703C-703
Author(s):  
Zana C. Somda ◽  
Harry A. Mills ◽  
Sharad C. Phatak
Keyword(s):  
Plant Growth ◽  
Plant Biomass ◽  
N Uptake ◽  
Nitrification Inhibitors ◽  
Inhibitory Effects ◽  
N Transformations ◽  
Tomato Plants ◽  
Inhibition Of Nitrification ◽  
Biological Nitrification

As a result of long-term application, some fungicides may accumulate in the soil to levels that can affect soil N transformations and plant growth. Studies were initiated to compare benomyl, captan, and lime-sulfur fungicides with the biological nitrification inhibitors (NI) nitrapyrin and terrazole for their effects on biological nitrification and denitrification, and tomato (Lycopersicon esculentum Mill.) growth and N uptake. In laboratory studies, inhibition of nitrification was less than 5% in a Tifton l.s. soil incubated with 10 μg g -1 a.i. of benomyl but was about 51%, 72%, and more than 85% when amended with lime-sulfur, captan, and NI, respectively. Similarly, increased inhibitory effects on denitrification of NO3 were obtained in a liquid media incubated anaerobically with either NI (37%) than captan or lime-sulfur (25%) while benomyl had no significant effect. In greenhouse studies with tomato plants, weekly drench applications of 0.25 μg a.i. g -1 soil of the appropriate chemical for 4 weeks with three NH4:NO3 ratios showed that the NI and captan produced the greatest plant biomass and N uptake, but benomyl and lime-sulfur had no main effect while all fungicides interacted with the N ratio to affect plant growth and N uptake.

Arbuscular mycorrhizal fungi alleviate abiotic stresses in potato plants caused by low phosphorus and deficit irrigation/partial root-zone drying

2018 ◽  
Vol 156 (1) ◽  
pp. 46-58 ◽  
Author(s):  
Caixia Liu ◽  
Sabine Ravnskov ◽  
Fulai Liu ◽  
Gitte H. Rubæk ◽  
Mathias N. Andersen
Keyword(s):  
Plant Growth ◽  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Growth Response ◽  
Root Zone ◽  
Plant Biomass ◽  
N Uptake ◽  
Arbuscular Mycorrhizal ◽  
P Fertilization ◽  
Low Phosphorus

AbstractDeficit irrigation (DI) improves water use efficiency (WUE), but the reduced water input often limits plant growth and nutrient uptake. The current study examined whether arbuscular mycorrhizal fungi (AMF) could alleviate abiotic stress caused by low phosphorus (P) fertilization and DI.A greenhouse experiment was conducted with potato grown with (P1) or without (P0) P fertilization, with AMF (M1+:Rhizophagus irregularisor M2+:Glomus proliferum) or AMF-free control (M−) and subjected to full irrigation (FI), DI or partial root-zone drying (PRD).Inoculation of M1+ and M2+ maintained or improved plant growth and P/nitrogen (N) uptake when subjected to DI/PRD and P0. However, the positive responses to AMF varied with P level and irrigation regime. Functional differences were found in ability of AMF species alleviating plant stress. The largest positive plant biomass response to M1+ and M2+ was found under FI, both at P1 and P0 (25% increase), while plant biomass response to M1+ and M2+ under DI/PRD (14% increase) was significantly smaller. The large growth response to AMF inoculation, particularly under FI, may relate to greater photosynthetic capacity and leaf area, probably caused by stimulation of plant P/N uptake and carbon partitioning toward roots and tubers. However, plant growth response to AMF was not related to the percentage of AMF root colonization. Arbuscular mycorrhizal fungi can maintain and improve P/N uptake, WUE and growth of plants both at high/low P levels and under FI/DI. If this is also the case under field conditions, it should be implemented for sustainable potato production.

The nitrification inhibitor dicyandiamide increases mineralization–immobilization turnover in slurry-amended grassland soil

2014 ◽  
Vol 152 (S1) ◽  
pp. 137-149 ◽  
Author(s):  
M. ERNFORS ◽  
F. P. BRENNAN ◽  
K. G. RICHARDS ◽  
K. L. MCGEOUGH ◽  
B. S. GRIFFITHS ◽  
...  
Keyword(s):  
Nitrification Inhibitor ◽  
Organic N ◽  
Nitrification Inhibitors ◽  
N Losses ◽  
N Transformations ◽  
Autotrophic Nitrification ◽  
Gross Mineralization ◽  
Soil N Mineralization ◽  
Inhibition Of Nitrification ◽  
Gross N Transformation

SUMMARYNitrification inhibitors are used in agriculture for the purpose of decreasing nitrogen (N) losses, by limiting the microbially mediated oxidation of ammonium (NH4+) to nitrate (NO3−). Successful inhibition of nitrification has been shown in numerous studies, but the extent to which inhibitors affect other N transformations in soil is largely unknown. In the present study, cattle slurry was applied to microcosms of three different grassland soils, with or without the nitrification inhibitor dicyandiamide (DCD). A solution containing NH4+and NO3−, labelled with15N either on the NH4+or the NO3−part, was mixed with the slurry before application. Gross N transformation rates were estimated using a15N tracing model. In all three soils, DCD significantly inhibited gross autotrophic nitrification, by 79–90%. Gross mineralization of recalcitrant organic N increased significantly with DCD addition in two soils, whereas gross heterotrophic nitrification from the same pool decreased with DCD addition in two soils. Fungal to bacterial ratios were not significantly affected by DCD addition. Total gross mineralization and immobilization increased significantly across the three soils when DCD was used, which suggests that DCD can cause non-target effects on soil N mineralization–immobilization turnover.

scholarly journals Enhancement of root architecture and nitrate transporter gene expression improves plant growth and nitrogen uptake under long-term low-nitrogen stress in barley (Hordeum vulgare L.) seedlings

2021 ◽  
Author(s):  
Runhong Gao ◽  
Guimei Guo ◽  
Hongwei Xu ◽  
Zhiwei Chen ◽  
Yingbo Li ◽  
...  
Keyword(s):  
Plant Growth ◽  
N Uptake ◽  
Dry Weight ◽  
Nitrate Transporter ◽  
Hordeum Vulgare L ◽  
N Accumulation ◽  
Influx Rate ◽  
Expression Levels ◽  
N Assimilation

AbstractOver application of nitrogen (N) fertilizers to crops ultimately causes N pollution in the ecosphere. Studying the response of plant growth and N uptake to low-N stress may aid in elucidating the mechanism of low N tolerance in plants and developing crop cultivars with high nitrogen use efficiency (NUE). In this study, a high-NUE mutant line A9-29 and the wild-type barley cultivar Hua30 were subjected to hydroponic culture with high and low N supply, and the dry weight, N accumulation, root morphology, and expression levels of the potential genes involved in nitrate uptake and assimilation were measured at seedling stage. The results showed that under low-N conditions, A9-29 had a higher dry weight, N content, N influx rate and larger root uptake area than did Hua30. Under long-term low-N stress, compared with Hua30, A9-29 demonstrated higher expression of the HvNRT2/3 genes, especially HvNRT2.1, HvNRT2.5, and HvNRT3.3. Similarly, the expression levels of N assimilation genes including HvNIA1, HvNIR1, HvGS1_1, HvGS1_3, and HvGLU2 increased significantly in A9-29. Taken together, our results suggested that the larger root area and the upregulation of nitrate transporter and assimilation genes may contribute to stronger N uptake capacity for plant growth and N accumulation in responding to long-term low-N stress. These findings may aid in understanding the mechanism of low N tolerance and developing barley cultivars with high-NUE.

scholarly journals Chlorophyll Fluorescence, Photosynthesis and Growth of Tomato Plants as Affected by Long-Term Oxygen Root Zone Deprivation and Grafting

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 137 ◽  
Author(s):  
Rosario Paolo Mauro ◽  
Michele Agnello ◽  
Miriam Distefano ◽  
Leo Sabatino ◽  
Alberto San Bautista Primo ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Plant Growth ◽  
Root Zone ◽  
Variable Fluorescence ◽  
Cherry Tomato ◽  
Tomato Plants ◽  
Hydroponic System ◽  
Root Hypoxia ◽  
Quantum Yield Of Psii

A greenhouse experiment was conducted to study the effects of the O2 root zone level and grafting on chlorophyll fluorescence, photosynthesis and growth of cherry tomato grown in a hydroponic system. Two O2 concentrations in the root zone, namely Ox (saturation level) and Ox- (2–3 mg L−1), were applied for 30 days on self-grafted cherry tomato Dreamer or grafted onto the hybrids Arnold, Beaufort, Maxifort and Top Pittam. Root hypoxia increased minimum fluorescence (by 10%) while it decreased variable fluorescence and the maximum quantum yield of PSII (up to 16 and 8%, respectively). Moreover, it reduced leaf photosynthesis, transpiration and stomatal conductance (by 12, 17 and 13%, respectively), whereas it increased leaf electrolyte leakage (by 2.1%). The graft combinations showed a different ability in buffering the effects of root hypoxia on plant growth and related components, and these differences were related to their root biomass. The minimum fluorescence was negatively correlated to plant growth, so it may be a useful indicator to select tolerant rootstocks to root hypoxia. Our results suggest the occurrence of both diffusive and metabolic constraints to tomato photosynthesis under root hypoxia, a condition that can be mitigated by selecting rootstocks with a more developed root system.

THE INFLUENCE OF RATE AND TIME OF MINERAL N APPLICATION ON YIELD AND N2 FIXATION BY FIELD BEAN

1989 ◽  
Vol 69 (2) ◽  
pp. 427-436 ◽  
Author(s):  
R. M. N. KUCEY
Keyword(s):  
Plant Growth ◽  
N Uptake ◽  
Control Plant ◽  
N Fertilizer ◽  
Field Bean ◽  
Inhibitory Effects ◽  
Plant N Uptake ◽  
Mineral N ◽  
N Application ◽  
Field Beans

Greenhouse experiments were conducted to determine the effect of rate and timing of nitrogen (N) fertilizer on growth, N uptake and N2 fixation by nodulated field beans (Phaseolus vulgaris L. ’GN1140’). Fertilizer N was added at 30, 60 or 120 mg kg−1 soil either at planting or at 2, 4, 6, 8 or 10 wk after planting. N2 fixation was determined by using 15N isotope dilution methods with spring wheat (Triticum aestivum ’Leader’) as a nonfixing control plant. Additions of N at 30 mg kg−1 soil had a stimulatory effect on plant growth, relative to plants not receiving N fertilizer, which was reflected in increased N uptake and N2 fixation. Addition of N at 60 or 120 mg kg−1 soil did not result in increased plant N uptake and was shown to inhibit N2 fixation. Stimulatory effects of 30 mg N, and inhibitory effects of 60 or 120 mg N, were only observed if N additions were made within the first 6 wk after planting. Additions of N after that time did not affect the plant parameters measured in this study. It was concluded that additions of N at rates of 60 or 120 mg kg−1 do not result in increased plant growth because of the resulting decreases in the contribution of biologically fixed N2 to plant N uptake. It was also concluded that once the N2-fixing symbioses with GN1140 was established, biological N2 fixation was able to supply sufficient N for the plant needs.Key words: 15N dilution, starter N, field bean, N2 fixation, N addition, wheat, Rhizobium phaseoli

scholarly journals Ethylene Evolution by Tomato Plants Receiving Nitrogen Nutrition from Urea

HortScience ◽  
1990 ◽  
Vol 25 (4) ◽  
pp. 420-421 ◽  
Author(s):  
Allen V. Barker ◽  
Kenneth A. Corey
Keyword(s):  
Plant Growth ◽  
Nitrogen Nutrition ◽  
Ethylene Evolution ◽  
Soil Culture ◽  
N Transformations ◽  
Relative Growth ◽  
Tomato Plants ◽  
The Media ◽  
Nutrient Solutions ◽  
Urea Fertilization

Urea fertilization of `Heinz 1350' tomato (Lycopersicon esculentum Mill.) in sand or soil culture did not enhance ethylene evolution or restrict growth relative to plants receiving \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathbf{NO}_{\mathbf{3}}^{\mathbf{-}}\) \end{document} whereas \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathbf{NO}_{\mathbf{4}}^{\mathbf{+}}\) \end{document} nutrition doubled the relative rates of ethylene evolution and restricted relative growth. Inhibitors of N transformations in media (nitrapyrin, Np; hydroquinone, HQ; and phenylphosphorodiamidate, PPD) had no apparent stimulator effects on ethylene evolution of plants grown on urea or \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathbf{NO}_{\mathbf{3}}^{\mathbf{-}}\) \end{document} nutrition in sand or soil. Ethylene evolution was enhanced by PPD relative to that by Np or HQ for plants receiving \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathbf{NO}_{\mathbf{4}}^{\mathbf{+}}\) \end{document} nutrition. Each inhibitor had toxic effects on plant growth. Increasing K+ supply from 0 to 8 mm in nutrient solutions decreased ethylene evolution and increased plant growth with urea fertilization. Urea had low phytotoxicity if its hydrolysis to \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathbf{NO}_{\mathbf{4}}^{\mathbf{+}}\) \end{document} was prevented in the media. Chemical names used: p-dihydroxybenzene (hydroquinone); benzenephosphorodiamide (phenylphosphorodiamidate); 2-chloro-6-(trichloromethyl)pyridine (nitrapyrin).

Mechanisms of nitrogen limitation affecting maize growth: a comparison of different modelling hypotheses

2009 ◽  
Vol 60 (8) ◽  
pp. 738 ◽  
Author(s):  
F. Y. Li ◽  
P. D. Jamieson ◽  
P. R. Johnstone ◽  
A. J. Pearson
Keyword(s):  
Plant Growth ◽  
Grain Yield ◽  
Plant Biomass ◽  
N Uptake ◽  
Growth Dynamics ◽  
Crop Growth ◽  
Growth And Yield ◽  
Growth Stages ◽  
Significant Difference ◽  
Leaf N

Two hypothetical mechanisms exist for quantifying crop nitrogen (N) demand and N-deficit effects on crop growth. The Critical N mechanism uses a critical N concentration, while the Leaf N mechanism distinguishes active N in leaves from the N elsewhere in shoots. These two mechanisms were implemented in parallel in a maize model (Amaize) to evaluate their adequacy in predicting crop growth and development. In the Leaf N mechanism, two approaches for quantifying N-deficit effects, by reducing green leaf area (GAI) or diluting specific leaf nitrogen (SLN), were also examined. The model-predicted plant biomass, grain yield, and N uptake were compared with measurements from 47 maize crops grown on 16 sites receiving different N fertiliser treatments. The results showed that model-predicted plant biomass, grain yield and N uptake were insensitive to the approaches used for quantifying N-deficit effects in the Leaf N mechanism. The model-predicted plant biomass, grain yield and N uptake using either N approach were significantly related to measurements (P < 0.01) but had considerable deviations (r2 = 0.66–0.69 for biomass, 0.50–0.54 for grain yield: 0.17–0.33 for N uptake). The linear fits of the predicted against measured values showed no significant difference (P > 0.1) among the three N approaches, with the Leaf N mechanism predicting smaller deviation than the Critical N mechanism. However, the Critical N mechanism was better in simulating plant growth dynamics in early plant growth stages. The Leaf N mechanism distinguished functional from structural N pools in plants, having a sound physiological base. The simulation using the Leaf N mechanism with both SLN dilution and GAI reduction for quantifying N-deficit effects was the best in predicting crop growth and yield.

scholarly journals Biological nitrification inhibition in the rhizosphere: determining interactions and impact on microbially mediated processes and potential applications

2020 ◽  
Vol 44 (6) ◽  
pp. 874-908
Author(s):  
Pierfrancesco Nardi ◽  
Hendrikus J Laanbroek ◽  
Graeme W Nicol ◽  
Giancarlo Renella ◽  
Massimiliano Cardinale ◽  
...  
Keyword(s):  
Ammonia Oxidation ◽  
Natural Phenomenon ◽  
Nitrification Inhibitors ◽  
Nitrification Inhibition ◽  
Microbial Conversion ◽  
N Losses ◽  
N2o Production ◽  
N Transformations ◽  
Potential Applications ◽  
Biological Nitrification

ABSTRACT Nitrification is the microbial conversion of reduced forms of nitrogen (N) to nitrate (NO3−), and in fertilized soils it can lead to substantial N losses via NO3− leaching or nitrous oxide (N2O) production. To limit such problems, synthetic nitrification inhibitors have been applied but their performance differs between soils. In recent years, there has been an increasing interest in the occurrence of biological nitrification inhibition (BNI), a natural phenomenon according to which certain plants can inhibit nitrification through the release of active compounds in root exudates. Here, we synthesize the current state of research but also unravel knowledge gaps in the field. The nitrification process is discussed considering recent discoveries in genomics, biochemistry and ecology of nitrifiers. Secondly, we focus on the ‘where’ and ‘how’ of BNI. The N transformations and their interconnections as they occur in, and are affected by, the rhizosphere, are also discussed. The NH4+ and NO3− retention pathways alternative to BNI are reviewed as well. We also provide hypotheses on how plant compounds with putative BNI ability can reach their targets inside the cell and inhibit ammonia oxidation. Finally, we discuss a set of techniques that can be successfully applied to solve unresearched questions in BNI studies.

scholarly journals Nodulation, nitrogen uptake and growth of lima bean in a composted tannery sludge-treated soil

2019 ◽  
Vol 49 (11) ◽  
Author(s):  
Sandra Mara Barbosa Rocha ◽  
Jadson Emanuel Lopes Antunes ◽  
Antonio Victor Cavalcante Rocha Silva ◽  
Louise Melo de Souza Oliveira ◽  
João Pedro Alves de Aquino ◽  
...  
Keyword(s):  
Plant Growth ◽  
Nitrogen Uptake ◽  
Chromium Content ◽  
N Uptake ◽  
Lima Bean ◽  
Phaseolus Lunatus ◽  
Tannery Sludge ◽  
Treated Soil ◽  
Lower Biomass

ABSTRACT: This study evaluated the responses of lima bean (Phaseolus lunatus L.) to application of composted tannery sludge on nodulation, N uptake and plant growth. For eight years, the compost was applied at rates of: 0, 2.5, 5, 10, and 20 Mg ha-1 (dry basis). Plants of lima bean showed higher nodulation in treatments with compost; however, nodules reported in these treatments presented lower biomass, size and diversity than those reported in treatment without compost. Accumulation of N increased with the application of the highest rate (20 Mg ha-1), while there was an increase in chromium content in shoot with the increase in compost rates. Thus, the use of composted tannery sludge, in long-term, increases the accumulation of chromium in plants, increasing nodulation, while decrease rhizobia diversity in nodules.

Effects of increasing salinity and 15N-labelled urea levels on growth, N uptake, and water use efficiency of young tomato plants

Soil Research ◽  
2004 ◽  
Vol 42 (3) ◽  
pp. 345 ◽  
Author(s):  
C. Kütük ◽  
G. Çaycı ◽  
L. K. Heng
Keyword(s):  
Electrical Conductivity ◽  
Plant Growth ◽  
Water Use Efficiency ◽  
Water Use ◽  
Root Zone ◽  
N Uptake ◽  
Sensitive Period ◽  
Tomato Plants ◽  
Salinity Levels ◽  
Use Efficiency

A greenhouse experiment was conducted to investigate the response of tomato plants (Lycopersicon lycopersicum L.) to salinity and to determine the interactive effects of salinity and nitrogen fertilisation on yield, nitrogen uptake, water use efficiency (WUE), and root-zone salinity during early plant growth. Furthermore, the effects of salinity and N fertilisation were evaluated by measurement of carbon isotope discrimination (Δ). Tomato plants were grown in pots filled with 8 kg (dry weight equivalent) of Krumbach sandy loam. Salinity treatments were imposed by irrigation water containing Na, Ca, and Mg salts and having electrical conductivity of 0, 3, 6, 9, and 12 dS/m at 25�C. 15N-labelled urea (10 atom % excess) was also applied at 0, 80, 160, and 240 mg N/kg soil. Increasing salinity reduced plant growth; fresh and dry weights of shoots and roots decreased significantly, except for the non-fertilised plants. The maximum growth reduction in shoots occurred due to salinity–N fertilisation relationships at 12 dS/m (59.4% reduction compared with 0 dS/m in 160 mg N/kg). Root growth was less affected than shoots. Vegetative growth and N content increased with increasing nitrogen treatment. However, salinity generally reduced N uptake by plants. Δ was negatively correlated with WUE at all salinity levels in young tomato plants. Similar correlations were also obtained between WUE and Δ at various N treatments; the result suggests that Δ is a useful tool for assessing stress conditions. Smaller Δ values were obtained when salinity or N level increased. Increasing N fertiliser increased WUE in plants, whereas increasing salinity increased WUE at 3 dS/m and decreased WUE to some extent at other salinity levels. Electrical conductivity of the root-zone increased due to increasing salinity and time, whereas pH decreased. It was concluded that the early stage of development was a salt sensitive period for tomato plants.

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