title: Effect of elevated CO₂ on phosphorus nutrition of phosphate-deficient Arabidopsis thaliana (L.) Heynh under different nitrogen forms.
abstract: Phosphorus (P) nutrition is always a key issue regarding plants responses to elevated CO(2). Yet it is unclear of how elevated CO(2) affects P uptake under different nitrogen (N) forms. This study investigated the influence of elevated CO(2) (800 µl l(-1)) on P uptake and utilization by Arabidopsis grown in pH-buffered phosphate (P)-deficient (0.5 µM) hydroponic culture supplying with 2mM nitrate (NO(3)(-)) or ammonium (NH(4)(+)). After 7 d treatment, elevated CO(2) enhanced the biomass production of both NO(3)(-)- and NH(4) (+)-fed plants but decreased the P amount absorbed per weight of roots and the P concentration in the shoots of plants supplied with NH(4)(+). In comparison, elevated CO(2) increased the amount of P absorbed per weight of roots, as well as the P concentration in plants and alleviated P deficiency-induced symptoms of plants supplied with NO(3)(-). Elevated CO(2) also increased the root/shoot ratio, total root surface area, and acid phosphatase activity, and enhanced the expression of genes or transcriptional factors involving in P uptake, allocation and remobilization in P deficient plants. Furthermore, elevated CO(2) increased the nitric oxide (NO) level in roots of NO(3)(-)-fed plants but decreased it in NH(4)(+)-fed plants. NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) inhibited plant P acquisition by roots under elevated CO(2). Considering all of these findings, this study concluded that a combination of elevated CO(2) and NO(3)(-) nutrition can induce a set of plant adaptive strategies to improve P status from P-deficient soluble sources and that NO may be a signalling molecule that controls these processes.
authors.affiliation: Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University,  Hangzhou 310058, China.
authors.forename: Yaofang
authors.initials: Y
authors.lastname: Niu
authors.forename: Rushan
authors.initials: R
authors.lastname: Chai
authors.forename: Huifen
authors.initials: H
authors.lastname: Dong
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.forename: Caixian
authors.initials: C
authors.lastname: Tang
authors.forename: Yongsong
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D001565:Benzoates / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects / Q000235:genetics; D018533:Biomass; D002245:Carbon Dioxide / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007093:Imidazoles / Q000494:pharmacology; D050901:Nitrate Reductase / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D009584:Nitrogen / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology; D010710:Phosphates / Q000172:deficiency* / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism*; D018517:Plant Roots / Q000033:anatomy & histology / Q000187:drug effects / Q000201:enzymology; D018520:Plant Shoots / Q000187:drug effects / Q000201:enzymology
chemical_list: D001565:Benzoates; D007093:Imidazoles; D010710:Phosphates; D002245:Carbon Dioxide; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; D009599:Nitroprusside; D010758:Phosphorus; D009569:Nitric Oxide; D050901:Nitrate Reductase; D000135:Acid Phosphatase; D009584:Nitrogen