scholarly journals Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

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.

scholarly journals Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

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.

scholarly journals Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

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.

scholarly journals Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

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.

scholarly journals Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency

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.

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

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.

scholarly journals Genome Wide Transcriptome Analysis Reveals Complex Regulatory Mechanisms Underlying Phosphate Homeostasis in Soybean Nodules

2018 ◽  
Vol 19 (10) ◽  
pp. 2924 ◽  
Author(s):  
Yingbin Xue ◽  
Qingli Zhuang ◽  
Shengnan Zhu ◽  
Bixian Xiao ◽  
Cuiyue Liang ◽  
...  
Keyword(s):  
Transcriptome Analysis ◽  
Molecular Mechanisms ◽  
Transcriptional Regulatory Network ◽  
Phosphorus Deficiency ◽  
Expression Patterns ◽  
P Deficiency ◽  
Pi Homeostasis ◽  
Genome Wide ◽  
Pi Starvation ◽  
Soybean Nodule

Phosphorus (P) deficiency is a major limitation for legume crop production. Although overall adaptations of plant roots to P deficiency have been extensively studied, only fragmentary information is available in regard to root nodule responses to P deficiency. In this study, genome wide transcriptome analysis was conducted using RNA-seq analysis in soybean nodules grown under P-sufficient (500 μM KH2PO4) and P-deficient (25 μM KH2PO4) conditions to investigate molecular mechanisms underlying soybean (Glycine max) nodule adaptation to phosphate (Pi) starvation. Phosphorus deficiency significantly decreased soybean nodule growth and nitrogenase activity. Nodule Pi concentrations declined by 49% in response to P deficiency, but this was well below the 87% and 88% decreases observed in shoots and roots, respectively. Nodule transcript profiling revealed that a total of 2055 genes exhibited differential expression patterns between Pi sufficient and deficient conditions. A set of (differentially expressed genes) DEGs appeared to be involved in maintaining Pi homeostasis in soybean nodules, including eight Pi transporters (PTs), eight genes coding proteins containing the SYG1/PHO81/XPR1 domain (SPXs), and 16 purple acid phosphatases (PAPs). The results suggest that a complex transcriptional regulatory network participates in soybean nodule adaption to Pi starvation, most notable a Pi signaling pathway, are involved in maintaining Pi homeostasis in nodules.

scholarly journals Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

2020 ◽  
Author(s):  
Xiaoyan Chen ◽  
Iva Dolinova ◽  
Alena Sevcu ◽  
Tomasz Jurczak ◽  
Piotr Frankiewicz ◽  
...  
Keyword(s):  
Early Stage ◽  
Phosphorus Deficiency ◽  
Photochemical Efficiency ◽  
Sustainable Growth ◽  
P Deficiency ◽  
P Content ◽  
Freshwater Bodies ◽  
P Utilization ◽  
Vigorous Growth ◽  
Globally Distributed

Abstract Background: The N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of freshwater and ocean worldwide. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies.Results: Based on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (sufficient inorganic P (Pi) as +DIP, α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as -P). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in fields and cultures respectively suggested that the excretion of APase was regulated by ambient Pi supply. Suffering from extreme P deficiency in the -P treatments, A. flos-aquae showed the highest APase activity reaching a vigorous growth at the early stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cellular P content. In the +DOP treatments, the coordination of dissolved organic P (DOP) mineralization and continuous utilization and formation of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage. Conclusion: A. flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while only a long-term sustainable growth could be maintained under DOP condition. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply.

scholarly journals Physiological responses and transcriptomic changes reveal the mechanisms underlying adaptation of Stylosanthes guianensis to phosphorus deficiency

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Zhijian Chen ◽  
Jianling Song ◽  
Xinyong Li ◽  
Jacobo Arango ◽  
Juan Andres Cardoso ◽  
...  
Keyword(s):  
Root Growth ◽  
Phosphorus Deficiency ◽  
Utilization Efficiency ◽  
Differentially Expressed ◽  
Purple Acid Phosphatase ◽  
Growth And Yield ◽  
P Deficiency ◽  
Stylosanthes Guianensis ◽  
Pi Homeostasis ◽  
Pi Starvation

Abstract Background Phosphorus (P) is an essential macronutrient for plant growth that participates in a series of biological processes. Thus, P deficiency limits crop growth and yield. Although Stylosanthes guianensis (stylo) is an important tropical legume that displays adaptation to low phosphate (Pi) availability, its adaptive mechanisms remain largely unknown. Results In this study, differences in low-P stress tolerance were investigated using two stylo cultivars (‘RY2’ and ‘RY5’) that were grown in hydroponics. Results showed that cultivar RY2 was better adapted to Pi starvation than RY5, as reflected by lower values of relative decrease rates of growth parameters than RY5 at low-P stress, especially for the reduction of shoot and root dry weight. Furthermore, RY2 exhibited higher P acquisition efficiency than RY5 under the same P treatment, although P utilization efficiency was similar between the two cultivars. In addition, better root growth performance and higher leaf and root APase activities were observed with RY2 compared to RY5. Subsequent RNA-seq analysis revealed 8,348 genes that were differentially expressed under P deficient and sufficient conditions in RY2 roots, with many Pi starvation regulated genes associated with P metabolic process, protein modification process, transport and other metabolic processes. A group of differentially expressed genes (DEGs) involved in Pi uptake and Pi homeostasis were identified, such as genes encoding Pi transporter (PT), purple acid phosphatase (PAP), and multidrug and toxin extrusion (MATE). Furthermore, a variety of genes related to transcription factors and regulators involved in Pi signaling, including genes belonging to the PHOSPHATE STARVATION RESPONSE 1-like (PHR1), WRKY and the SYG1/PHO81/XPR1 (SPX) domain, were also regulated by P deficiency in stylo roots. Conclusions This study reveals the possible mechanisms underlying the adaptation of stylo to P deficiency. The low-P tolerance in stylo is probably manifested through regulation of root growth, Pi acquisition and cellular Pi homeostasis as well as Pi signaling pathway. The identified genes involved in low-P tolerance can be potentially used to design the breeding strategy for developing P-efficient stylo cultivars to grow on acid soils in the tropics.

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

2018 ◽  
Vol 19 (10) ◽  
pp. 2964 ◽  
Author(s):  
Mohammad Karim ◽  
Xiaoying Dong ◽  
Lu Zheng ◽  
Renfang Shen ◽  
Ping Lan
Keyword(s):  
Root Tip ◽  
Marker Genes ◽  
Soluble Phosphate ◽  
P Deficiency ◽  
Pi Starvation ◽  
Underlying Mechanisms ◽  
Pi Deficiency ◽  
Open Question ◽  
Experimental Stage

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.

scholarly journals Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

2020 ◽  
Author(s):  
Xiaoyan Chen ◽  
Iva Dolinova ◽  
Alena Sevcu ◽  
Tomasz Jurczak ◽  
Piotr Frankiewicz ◽  
...  
Keyword(s):  
Phosphorus Deficiency ◽  
Photochemical Efficiency ◽  
Sustainable Growth ◽  
P Deficiency ◽  
Freshwater Bodies ◽  
P Utilization ◽  
Culture Stage ◽  
Vigorous Growth ◽  
Globally Distributed

Abstract Background The N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of fresh and marine water bodies. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies. Results Based on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (dissolved inorganic P (Pi) as +DIP, dissolved organic α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as P-depleted). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in both fields and cultures suggested that the excretion of APase in cyanobacterium was regulated by ambient Pi supply. Suffering from P deficiency in the P-depleted treatments, A. flos-aquae showed the highest APase activity but a vigorous growth at the early culture stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cell P quota. In the +DOP treatments, the coordination of dissolved DOP mineralization and continuous prompt utilization of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the specific growth rate kept around 0 cells L-1 day-1 at the second half culture period and the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage. Conclusion A. flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while it maintained a long-term sustainable growth but not reproduction under sole DOP supply. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply.

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