Effect of silicon on root growth, ionomics and antioxidant performance of maize roots exposed to As toxicity

AbstractIn this study, the effects of Cd on root growth, respiration, and transmembrane electric potential (E m) of the outer cortical cells in maize roots treated with various Cd concentrations (from 1 µM to 1 mM) for several hours to one week were studied. The E m values of root cells ranged between −120 and −140 mV and after addition of Cd they were depolarized immediately. The depolarization was concentration-dependent reaching the value of diffusion potential (E D) when the Cd concentration exceeded 100 µM. The values of E D ranged between −65 to −68 mV (−66 ± 1.42 mV). The maximum depolarization of E m was registered approx. 2.5 h after addition of Cd to the perfusion solution and in some cases, partial (Cd > 100 µM) or complete repolarization (Cd < 100 µM) was observed within 8–10 h of Cd treatment. In the time-dependent experiments (0 to 168 h) shortly after the maximum repolarization of E m a continuous concentration-dependent decrease of E m followed at all Cd concentrations. Depolarization of E m was accompanied by both increased electrolyte leakage and inhibition of respiration, especially in the range of 50 µM to 1 mM Cd, with the exception of root cells treated with 1 and 10 µM Cd for 24 and 48 h. Time course analysis of Cd impact on root respiration revealed that at higher Cd concentrations (> 50 µM) the respiration gradually declined (∼ 6 h) and then remained at this lowest level for up to 24 h.All the Cd concentrations used in this experiment induced significant inhibition of root elongation and concentrations higher than 100 µM stopped the root growth within the first day of Cd treatment. Our results suggest that Cd does not cause irreversible changes in the electrogenic plasma membrane H+ ATPase because fusicoccin, an H+ ATPase activator diminished the depolarizing effect of Cd on the E m. The depolarization of E m in the outer cortical cells of maize roots was the result of a cumulative effect of Cd on ATP supply, plasmalemma permeability, and activity of H+ ATPase.

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Silicon improves salinity tolerance and affects ammonia assimilation in maize roots

Biologia ◽

10.2478/s11756-014-0411-7 ◽

2014 ◽

Vol 69 (9) ◽

Cited By ~ 12

Author(s):

Zuzana Kochanová ◽

Katarína Jašková ◽

Barbora Sedláková ◽

Miroslava Luxová

Keyword(s):

Root Growth ◽

Growth Inhibition ◽

Electrolyte Leakage ◽

Ammonia Assimilation ◽

Root Growth Inhibition ◽

Time Range ◽

Saline Stress ◽

Protective Effects ◽

Plant Vigour ◽

Maize Roots

AbstractThe present study was conducted to evaluate the effect of different salt concentrations (50 and 200 mM NaCl) on growth, permeability properties (electrolyte leakage, cell viability) and activity of glutamine synthetase (GS) and glutamate dehydrogenase (GDH) in roots of maize seedlings. Both salt concentrations significantly affected growth and permeability properties of maize seedling roots and this negative effect increased with concentration of salt and duration of experiments. On the other hand salinity induced only small changes in the activities of GS and GDH, usually small increase in the activity was observed. To characterise the possible protective effect of silicon (Si) on maize roots exposed to saline stress, different concentrations of Si were simultaneously applied to both, low (50 mM) and high (200 mM) salt concentrations. Possible protective effects of Si on studied parameters were analysed in time range of 3 days treatment with the most positive effect on salt-induced root growth inhibition at high salt concentration and electrolyte leakage. The results show significant increase in GDH activity under all the tested conditions, although the mechanisms underlying this increase have not been elucidated. The results indicate that silicon may ameliorate the salt-induced root growth inhibition and increase the plant vigour at stressful conditions.

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Temporal and Spatial Profiling of Root Growth Revealed Novel Response of Maize Roots under Various Nitrogen Supplies in the Field

PLoS ONE ◽

10.1371/journal.pone.0037726 ◽

2012 ◽

Vol 7 (5) ◽

pp. e37726 ◽

Cited By ~ 36

Author(s):

Yunfeng Peng ◽

Xuexian Li ◽

Chunjian Li

Keyword(s):

Root Growth ◽

Spatial Profiling ◽

Maize Roots ◽

Temporal And Spatial ◽

Nitrogen Supplies

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Influence of graphene on the multiple metabolic pathways of Zea mays roots based on transcriptome analysis

PLoS ONE ◽

10.1371/journal.pone.0244856 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0244856

Author(s):

Zhiwen Chen ◽

Jianguo Zhao ◽

Jie Song ◽

Shenghua Han ◽

Yaqin Du ◽

...

Keyword(s):

Zea Mays ◽

Root Growth ◽

Growth And Development ◽

Plant Root ◽

Control Group ◽

Molecular Response ◽

Root Tips ◽

Positive Effects ◽

Maize Seeds ◽

Maize Roots

Graphene reportedly exerts positive effects on plant root growth and development, although the corresponding molecular response mechanism remains to be elucidated. Maize seeds were randomly divided into a control and experimental group, and the roots of Zea mays L. seedlings were watered with different concentrations (0–100 mg/L) of graphene to explore the effects and molecular mechanism of graphene on the growth and development of Z. mays L. Upon evaluating root growth indices, 50 mg/L graphene remarkably increased total root length, root volume, and the number of root tips and forks of maize seedlings compared to those of the control group. We observed that the contents of nitrogen and potassium in rhizosphere soil increased following the 50 mg/L graphene treatment. Thereafter, we compared the transcriptome changes in Z. mays roots in response to the 50 mg/L graphene treatment. Transcriptional factor regulation, plant hormone signal transduction, nitrogen and potassium metabolism, as well as secondary metabolism in maize roots subjected to graphene treatment, exhibited significantly upregulated expression, all of which could be related to mechanisms underlying the response to graphene. Based on qPCR validations, we proposed several candidate genes that might have been affected with the graphene treatment of maize roots. The transcriptional profiles presented here provide a foundation for deciphering the mechanism underlying graphene and maize root interaction.

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Hydrogen-Rich Water Improvement of Root Growth in Maize Exposed to Saline Stress

10.21203/rs.3.rs-101510/v1 ◽

2020 ◽

Author(s):

Liyan Yang ◽

Jingyun Tian ◽

Manxi Zhu ◽

Bo Yu ◽

YI Sun

Keyword(s):

Root Growth ◽

Molecular Mechanisms ◽

Biomass Accumulation ◽

Histochemical Staining ◽

Hydrogen Gas ◽

Saline Stress ◽

Beneficial Effects ◽

Oxidant Damage ◽

Maize Roots ◽

Mda Content

Abstract Background: Hydrogen gas (H2) is a newly-discovered signaling molecular that plays an important role in plants. This study investigated physiological and molecular mechanisms of hydrogen-rich water (HRW)-mediated beneficial effects on maize roots exposed to saline stress. Results: The results showed that growth of maize seedlings treated with 150 mM NaCl was greatly reduced. Under saline stress, 50% HRW diminished lipid damage in root which was confirmed by malondialdehyde (MDA) content assay and root histochemical staining, and the decreased activities of dismutase (SOD) and peroxidase (POD) further verified the reduced oxidant damage in roots cells under saline stress. HRW up-regulated the expression of ZmSOS1, ZmSKOR, and especially CDPK21 under saline stress, and it also stimulated the activities of PM H+-ATPase and tonoplast H+-ATPase and H+-PPase in maize roots. Thereby, Na+ content was decreased and K+ uptake was increased with the application of HRW. Conclusion: In summary, under saline stress, exogenous HRW application on maize roots up-regulated the key genes expression, improved H+-transport activity and thereby maintained the Na+/K+ balance, diminished oxidant damage and therefore promoted the root growth and biomass accumulation. Our results suggested exogenous HRW treatment on maize could improve root development under saline conditions and might be applied to alleviate salinity stress.

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The influence of mechanical resistance and phosphate supply on morphology and function of maize roots.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v30i3.16977 ◽

1982 ◽

Vol 30 (3) ◽

pp. 179-192 ◽

Cited By ~ 1

Author(s):

F.R. Boone ◽

B.W. Veen

Keyword(s):

Root Growth ◽

Shoot Growth ◽

Sandy Loam ◽

Specific Root Length ◽

Mechanical Resistance ◽

P Availability ◽

Low Light ◽

Maize Roots ◽

And Function ◽

Different Levels

In 3 pot experiments, maize cv. Avanti was grown on a marine sandy loam compacted to different pore vol. and supplied with different rates of P. Root wt. was not changed by different levels of mechanical resistance but root extension growth and cone resistance were curvilinearly related. At high mechanical resistance, root growth was more horizontal; vertical root growth was very limited at high cone resistances. Specific root length was also smaller, root diam. larger and fewer laterals/cm main root were developed although their av. length was not affected. The influence of mechanical resistance on root distribution and morphology reduced nutrient uptake and therefore shoot growth. With low P availability, P limited shoot growth more the higher the mechanical resistance. With sufficient P, K had the same effect. If an aboveground factor such as a low light intensity limited shoot growth, mechanical resistance had no effect on shoot growth. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Root growth regulation and gravitropism in maize roots does not require the epidermis

Planta ◽

10.1007/bf00194511 ◽

1991 ◽

Vol 185 (1) ◽

Cited By ~ 5

Author(s):

Thomas Bj�rkman ◽

RobertE. Cleland

Keyword(s):

Root Growth ◽

Growth Regulation ◽

Maize Roots

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Seed ageing-induced inhibition of germination and post-germination root growth is related to lower activity of plasma membrane H+-ATPase in maize roots

Journal of Plant Physiology ◽

10.1016/j.jplph.2008.01.012 ◽

2009 ◽

Vol 166 (2) ◽

pp. 128-135 ◽

Cited By ~ 21

Author(s):

Hólmfríđur Sveinsdóttir ◽

Feng Yan ◽

Yiyong Zhu ◽

Tina Peiter-Volk ◽

Sven Schubert

Keyword(s):

Plasma Membrane ◽

Root Growth ◽

Lower Activity ◽

Maize Roots ◽

Seed Ageing

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Root abundance of maize in conventionally-tilled and zero-tilled soils of Argentina

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832008000200031 ◽

2008 ◽

Vol 32 (2) ◽

pp. 769-779 ◽

Cited By ~ 8

Author(s):

Miguel Angel Taboada ◽

Carina Rosa Alvarez

Keyword(s):

Root Growth ◽

Mechanical Impedance ◽

Maize Root ◽

Silty Clay ◽

Clay Loam ◽

Silty Clay Loam ◽

Penetrometer Resistance ◽

Maize Roots ◽

Root Abundance ◽

Different Soils

Maize root growth is negatively affected by compacted layers in the surface (e.g. agricultural traffic) and subsoil layers (e.g. claypans). Both kinds of soil mechanical impedances often coexist in maize fields, but the combined effects on root growth have seldom been studied. Soil physical properties and maize root abundance were determined in three different soils of the Rolling Pampa of Argentina, in conventionally-tilled (CT) and zero-tilled (ZT) fields cultivated with maize. In the soil with a light Bt horizon (loamy Typic Argiudoll, Chivilcoy site), induced plough pans were detected in CT plots at a depth of 0-0.12 m through significant increases in bulk density (1.15 to 1.27 Mg m-3) and cone (tip angle of 60 º) penetrometer resistance (7.18 to 9.37 MPa in summer from ZT to CT, respectively). This caused a reduction in maize root abundance of 40-80 % in CT compared to ZT plots below the induced pans. Two of the studied soils had hard-structured Bt horizons (clay pans), but in only one of them (silty clay loam Abruptic Argiudoll, Villa Lía site) the expected penetrometer resistance increases (up to 9 MPa) were observed with depth. In the other clay pan soil (silty clay loam Vertic Argiudoll, Pérez Millán site), penetrometer resistance did not increase with depth but reached 14.5 MPa at 0.075 and 0.2 m depth in CT and ZT plots, respectively. However, maize root abundance was stratified in the first 0.2 m at the Villa Lía and Pérez Millán sites. There, the hard Bt horizons did not represent an absolute but a relative mechanical impedance to maize roots, by the observed root clumping through desiccation cracks.

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