Journal Article

Influence of High CO<sub>2</sub>Partial Pressure on Nitrogen Use Efficiency of the C<sub>4</sub>Grasses <i>Panicum coloratum</i> and <i>Cenchrus ciliaris</i>

Silvia G. Rudmann, Paul J. Milham and Jann P. Conroy

in Annals of Botany

Published on behalf of The Annals of Botany Company

Volume 88, issue 4, pages 571-577
Published in print October 2001 | ISSN: 0305-7364
Published online October 2001 | e-ISSN: 1095-8290 | DOI:
Influence of High CO2Partial Pressure on Nitrogen Use Efficiency of the C4Grasses Panicum coloratum and Cenchrus ciliaris

More Like This

Show all results sharing these subjects:

  • Ecology and Conservation
  • Evolutionary Biology
  • Plant Sciences and Forestry


Show Summary Details


Australia's tropical grasslands are dominated by C4grasses, characterized by their unique biochemistry and anatomy. Two naturalized C4grasses (Panicum coloratum and Cenchrus ciliaris) were used to investigate whether high CO2partial pressure [ p(CO2)] influences photosynthetic nitrogen use efficiency and plant nitrogen use efficiency (PNUE and NUE respectively). Plants were grown for 30 d with four levels of N at p(CO2) of 38 or 86 Pa. PNUE was calculated from leaf CO2assimilation rates (A) and leaf N concentrations, and NUE from total leaf N content and plant dry mass. At each p(CO2), PNUE and NUE were greater for C. ciliaris than for P. coloratum due to higher A and dry mass combined with lower leaf N concentrations. Elevatedp (CO2) increased PNUE of C. ciliaris only. This effect was due to lower leaf N concentrations (area basis). At high p(CO2), NUE of C. ciliaris was also greater. This resulted from a 1.6-fold stimulation of dry mass by high p(CO2). Although dry mass of P. coloratum was increased 1.2-fold by elevated p(CO2), its NUE was unaffected. Leaf transpiration rates were halved at elevated p(CO2), and we suggest that this factor plays a major role in the growth response of C4grasses to high p(CO2). Copyright 2001 Annals of Botany Company

Keywords: Panicum coloratum, Cenchrus ciliaris, nitrogen use efficiency, elevated CO2, leaf N concentration, growth, photosynthesis

Journal Article.  10 words. 

Subjects: Ecology and Conservation ; Evolutionary Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.