Can Aluminum Tolerant Wheat Cultivar Perform Better under Phosphate Deficient Conditions?

Low availability of inorganic phosphate (Pi), together with aluminum (Al), is a major constraint for plant growth and development in acidic soils. To investigate whether or not Al-resistant cultivars can perform better under Pi deficiency, we chose two wheat cultivars with different Al-responses—Atlas 66, being Al-tolerant, and Scout 66, which is Al-sensitive—and analyzed their responses to Pi deficiency. Results showed that, unexpectedly, the Al-sensitive cultivar Scout 66 contained comparatively higher amount of soluble phosphate (Pi) and total phosphorus (P) both in the roots and in the shoots than Atlas 66 under P deficiency. In addition, Scout 66 exhibited higher root biomass, root volume, and root tip numbers, compared with Atlas 66. The expression of Pi-responsive marker genes, TaIPS1, TaSPX3, and TaSQD2 was strongly induced in both cultivars, but the extents of induction were higher in Scout 66 than in Atlas 66 under long-term Pi starvation. Taken together, our results suggest that the Al-sensitive cultivar Scout 66 performed much better under sole Pi starvation, which sets the following experimental stage to uncover the underlying mechanisms of why Scout 66 can display better under Pi deficiency. Our study also raises an open question whether Al-resistant plants are more sensitive to Pi deficiency.

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Characterization of two cis-acting elements, P1BS and W-box, in the regulation of OsPT6 responsive to phosphors deficiency

Plant Growth Regulation ◽

10.1007/s10725-020-00688-z ◽

2021 ◽

Author(s):

Qingchun Zhao ◽

Zhenzhen Luo ◽

Jiadong Chen ◽

Hongfang Jia ◽

Penghui Ai ◽

...

Keyword(s):

Gus Expression ◽

Element Analysis ◽

P Deficiency ◽

Targeted Deletion ◽

Cis Acting ◽

Gus Reporter ◽

Pi Starvation ◽

Expression Activity ◽

Underlying Mechanisms ◽

Diverse Plant Species

AbstractPhosphorus (P) deficiency is one of the major nutrient stresses restricting plant growth. The uptake of P by plants from soil is mainly mediated by the phosphate (Pi) transporters belonging to the PHT1 family. Multiple PHT1 genes from diverse plant species have been shown to be strongly up-regulated upon Pi starvation, however, the underlying mechanisms for the Pi-starvation-induced (PSI) up-regulation have not been well deciphered for most Pi transporter genes. Here, we reported a detailed dissection of the promoter activity of a PSI rice Pi transporter gene OsPT6, using the β-glucuronidase (GUS) reporter gene. OsPT6 promoter could drive GUS expression strongly in both roots and blades of rice plants grown under low P, but not high P. Cis-acting element analysis identified one copy of the P1BS motif and two copies of the W-box motif in OsPT6 promoter. Targeted deletion of the P1BS motif caused almost complete abolition of GUS induction in response to Pi starvation, irrespective of the presence or absence of the W-box motif, Four repeats of the P1BS motif fused to the CaMV35S minimal promoter was sufficient to induce GUS expression responsive to Pi starvation. Targeted deletion of the upstream W-box motif (W1) did not affect the GUS expression activity compared with the full-length OsPT6 promoter, while targeted deletion of the downstream W-box motif (W2) or both of the W-box motifs remarkably reduced the GUS induction rate upon Pi starvation. Our results proposed that the PSI response of OsPT6 was positively regulated by at least two elements, the sole P1BS and the downstream W-box, in its promoter, and the W-box-mediated up-regulation of OsPT6 might be highly dependent on the P1BS motif.

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Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

10.21203/rs.2.13121/v4 ◽

2020 ◽

Author(s):

Jiajia Luo ◽

Yunxi Liu ◽

Huikai Zhang ◽

Jinpeng Wang ◽

Zhijian Chen ◽

...

Keyword(s):

Phenolic Acids ◽

Phosphorus Deficiency ◽

Acid Soils ◽

Pcr Analysis ◽

P Deficiency ◽

Adaptive Mechanisms ◽

Pi Starvation ◽

P Utilization ◽

Metabolic Profiling Analysis ◽

Underlying Mechanisms

Abstract Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown.Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the growth of stylo root was enhanced, which was attributed to the up-regulation of expansin genes participating in root growth. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulations were identified in stylo roots response to P deficiency, which mainly included flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots subjected to low P stress. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were increased in P-deficient stylo roots. Furthermore, the qRT-PCR analysis showed that a set of genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundances of phenolic acids and phenylamides were significantly increased in stylo roots during P deficiency. The increased accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo.Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and increasing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo roots to P deficiency.

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Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

10.21203/rs.2.13121/v3 ◽

2019 ◽

Author(s):

Jiajia Luo ◽

Yunxi Liu ◽

Huikai Zhang ◽

Jinpeng Wang ◽

Zhijian Chen ◽

...

Keyword(s):

Phenolic Acids ◽

Phosphorus Deficiency ◽

Acid Soils ◽

P Deficiency ◽

Adaptive Mechanisms ◽

Pi Starvation ◽

P Utilization ◽

Metabolic Profiling Analysis ◽

Underlying Mechanisms ◽

Wall Loosening

Abstract Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown. Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the root growth in stylo was significantly enhanced, which was accompanied with up-regulation of expansin genes participating in cell wall loosening. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulation were identified in stylo roots responding to P deficiency, which mainly include flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were significantly increased in P-deficient stylo roots. Furthermore, the transcripts of various genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundance of phenolic acids and phenylamides was significantly increased in stylo roots during P deficiency. The enhanced accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo. Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and enhancing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo to P deficiency.

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Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

10.21203/rs.2.13121/v5 ◽

2020 ◽

Author(s):

Jiajia Luo ◽

Yunxi Liu ◽

Huikai Zhang ◽

Jinpeng Wang ◽

Zhijian Chen ◽

...

Keyword(s):

Phenolic Acids ◽

Phosphorus Deficiency ◽

Acid Soils ◽

P Deficiency ◽

Adaptive Mechanisms ◽

Pi Starvation ◽

P Utilization ◽

Metabolic Profiling Analysis ◽

Underlying Mechanisms ◽

Wall Loosening

Abstract Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown. Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the root growth in stylo was significantly enhanced, which was accompanied with up-regulation of expansin genes participating in cell wall loosening. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulation were identified in stylo roots responding to P deficiency, which mainly include flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were significantly increased in P-deficient stylo roots. Furthermore, the transcripts of various genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundance of phenolic acids and phenylamides was significantly increased in stylo roots during P deficiency. The enhanced accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo. Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and enhancing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo to P deficiency.

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Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

10.21203/rs.2.13121/v6 ◽

2020 ◽

Author(s):

Jiajia Luo ◽

Yunxi Liu ◽

Huikai Zhang ◽

Jinpeng Wang ◽

Zhijian Chen ◽

...

Keyword(s):

Phenolic Acids ◽

Phosphorus Deficiency ◽

Acid Soils ◽

P Deficiency ◽

Adaptive Mechanisms ◽

Pi Starvation ◽

P Utilization ◽

Metabolic Profiling Analysis ◽

Underlying Mechanisms ◽

Wall Loosening

Abstract Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown. Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the root growth in stylo was significantly enhanced, which was accompanied with up-regulation of expansin genes participating in cell wall loosening. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulation were identified in stylo roots responding to P deficiency, which mainly include flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were significantly increased in P-deficient stylo roots. Furthermore, the transcripts of various genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundance of phenolic acids and phenylamides was significantly increased in stylo roots during P deficiency. The enhanced accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo. Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and enhancing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo to P deficiency.

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Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

10.21203/rs.2.13121/v2 ◽

2019 ◽

Author(s):

Jiajia Luo ◽

Yunxi Liu ◽

Huikai Zhang ◽

Jinpeng Wang ◽

Zhijian Chen ◽

...

Keyword(s):

Phenolic Acids ◽

Phosphorus Deficiency ◽

Acid Soils ◽

P Deficiency ◽

Adaptive Mechanisms ◽

Pi Starvation ◽

P Utilization ◽

Metabolic Profiling Analysis ◽

Underlying Mechanisms ◽

Wall Loosening

Abstract Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown. Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the root growth in stylo was significantly enhanced, which was accompanied with up-regulation of expansin genes participating in cell wall loosening. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulation were identified in stylo roots responding to P deficiency, which mainly include flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were significantly increased in P-deficient stylo roots. Furthermore, the transcripts of various genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundance of phenolic acids and phenylamides was significantly increased in stylo roots during P deficiency. The enhanced accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo. Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and enhancing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo to P deficiency.

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Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960

Science ◽

10.1126/science.1239207 ◽

2013 ◽

Vol 341 (6150) ◽

pp. 1085-1089 ◽

Cited By ~ 221

Author(s):

H. D. Graven ◽

R. F. Keeling ◽

S. C. Piper ◽

P. K. Patra ◽

B. B. Stephens ◽

...

Keyword(s):

Boreal Forests ◽

Atmospheric Carbon Dioxide ◽

Ecosystem Models ◽

The North ◽

Ecological Changes ◽

Term Change ◽

Major Shift ◽

Underlying Mechanisms ◽

Global Carbon

Seasonal variations of atmospheric carbon dioxide (CO2) in the Northern Hemisphere have increased since the 1950s, but sparse observations have prevented a clear assessment of the patterns of long-term change and the underlying mechanisms. We compare recent aircraft-based observations of CO2 above the North Pacific and Arctic Oceans to earlier data from 1958 to 1961 and find that the seasonal amplitude at altitudes of 3 to 6 km increased by 50% for 45° to 90°N but by less than 25% for 10° to 45°N. An increase of 30 to 60% in the seasonal exchange of CO2 by northern extratropical land ecosystems, focused on boreal forests, is implicated, substantially more than simulated by current land ecosystem models. The observations appear to signal large ecological changes in northern forests and a major shift in the global carbon cycle.

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Sex-specifically responsive strategies to phosphorus availability combined with different soil nitrogen forms in dioecious Populus cathayana

Journal of Plant Ecology ◽

10.1093/jpe/rtab025 ◽

2021 ◽

Author(s):

Xiucheng Liu ◽

Yuting Wang ◽

Shuangri Liu ◽

Miao Liu

Keyword(s):

Root Length ◽

Root Length Density ◽

Specific Root Length ◽

P Uptake ◽

Root Tip ◽

P Availability ◽

P Deficiency ◽

Populus Cathayana ◽

Leaf P ◽

P Supply

Abstract Aims Phosphorus (P) availability and efficiency are especially important for plant growth and productivity. However, the sex-specific P acquisition and utilization strategies of dioecious plant species under different N forms are not clear. Methods This study investigated the responsive mechanisms of dioecious Populus cathayana females and males based on P uptake and allocation to soil P supply under N deficiency, nitrate (NO3 −) and ammonium (NH4 +) supply. Important Findings Females had a greater biomass, root length density (RLD), specific root length (SRL) and shoot P concentration than males under normal P availability with two N supplies. NH4 + supply led to higher total root length, RLD and SRL but lower root tip number than NO3 − supply under normal P supply. Under P deficiency, males showed a smaller root system but greater photosynthetic P availability and higher leaf P remobilization, exhibiting a better capacity to adaptation to P-deficiency than females. Under P deficiency, NO3 − supply increased leaf photosynthesis and PUE but reduced RLD and SRL in females while males had higher leaf P redistribution and photosynthetic PUE than NH4 + supply. Females had a better potentiality to cope with P deficiency under NO3 − supply than NH4 + supply; the contrary was true for males. These results suggest that females may devote to increase in P uptake and shoot P allocation under normal P availability, especially under NO3 − supply, while males adopt more efficient resource use and P remobilization to maximum their tolerance to P-deficiency.

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Blood–brain barrier disruption and ventricular enlargement are the earliest neuropathological changes in rats with repeated sub-concussive impacts over 2 weeks

Scientific Reports ◽

10.1038/s41598-021-88854-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bailey Hiles-Murison ◽

Andrew P. Lavender ◽

Mark J. Hackett ◽

Joshua J. Armstrong ◽

Michael Nesbit ◽

...

Keyword(s):

Oxidative Stress ◽

Blood Brain Barrier ◽

Hippocampal Formation ◽

Brain Barrier ◽

Lateral Ventricles ◽

Blood Brain Barrier Disruption ◽

Blood Brain ◽

Brain Barrier Disruption ◽

Underlying Mechanisms

AbstractRepeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood–brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.

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Remediation of mercury-contaminated soils and sediments using biochar: a critical review

Biochar ◽

10.1007/s42773-021-00087-1 ◽

2021 ◽

Author(s):

Qian Yang ◽

Yongjie Wang ◽

Huan Zhong

Keyword(s):

Health Risks ◽

Contaminated Soils ◽

Functional Materials ◽

Redox Conditions ◽

Existing Problems ◽

Soils And Sediments ◽

Underlying Mechanisms ◽

Biochar Amendment

AbstractThe transformation of mercury (Hg) into the more toxic and bioaccumulative form methylmercury (MeHg) in soils and sediments can lead to the biomagnification of MeHg through the food chain, which poses ecological and health risks. In the last decade, biochar application, an in situ remediation technique, has been shown to be effective in mitigating the risks from Hg in soils and sediments. However, uncertainties associated with biochar use and its underlying mechanisms remain. Here, we summarize recent studies on the effects and advantages of biochar amendment related to Hg biogeochemistry and its bioavailability in soils and sediments and systematically analyze the progress made in understanding the underlying mechanisms responsible for reductions in Hg bioaccumulation. The existing literature indicates (1) that biochar application decreases the mobility of inorganic Hg in soils and sediments and (2) that biochar can reduce the bioavailability of MeHg and its accumulation in crops but has a complex effect on net MeHg production. In this review, two main mechanisms, a direct mechanism (e.g., Hg-biochar binding) and an indirect mechanism (e.g., biochar-impacted sulfur cycling and thus Hg-soil binding), that explain the reduction in Hg bioavailability by biochar amendment based on the interactions among biochar, soil and Hg under redox conditions are highlighted. Furthermore, the existing problems with the use of biochar to treat Hg-contaminated soils and sediments, such as the appropriate dose and the long-term effectiveness of biochar, are discussed. Further research involving laboratory tests and field applications is necessary to obtain a mechanistic understanding of the role of biochar in reducing Hg bioavailability in diverse soil types under varying redox conditions and to develop completely green and sustainable biochar-based functional materials for mitigating Hg-related health risks.

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