Responses of leaf C:N:P stoichiometry to water supply in the desert shrub Zygophyllum xanthoxylum

D. Niu, C. Zhang, P. Ma, H. Fu, James Elser

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Based on the elemental composition of major biochemical molecules associated with different biological functions, the ‘growth rate hypothesis’ proposed that organisms with a higher growth rate would be coupled to lower C:N, especially lower C:P and N:P ratios. However, the applicability of the growth rate hypothesis for plants is unclear, especially for shrubs growing under different water supply. We performed an experiment with eight soil moisture levels (soil water content: 4%, 6%, 8%, 13%, 18%, 23%, 26% and 28%) to evaluate the effects of water availability on leaf C:N:P stoichiometry in the shrub Zygophyllum xanthoxylum. We found that leaves grew slowly and favored accumulation of P over C and N under both high and low water supply. Thus, leaf C:P and N:P ratios were unimodally related to soil water content, in parallel with individual leaf area and mass. As a result, there were significant positive correlations between leaf C:P and N:P with leaf growth (u). Our result that slower-growing leaves had lower C:P and N:P ratios does not support the growth rate hypothesis, which predicted a negative association of N:P ratio with growth rate, but it is consistent with recent theoretical derivations of growth–stoichiometry relations in plants, where N:P ratio is predicted to increase with increasing growth for very low growth rates, suggesting leaf growth limitation by C and N rather than P for drought and water saturation.

Original languageEnglish (US)
Pages (from-to)82-88
Number of pages7
JournalPlant Biology
Volume21
Issue number1
DOIs
StatePublished - Jan 1 2019

Keywords

  • Individual leaf area and mass
  • individual leaf growth rate
  • leaf stoichiometry
  • nitrogen:phosphorus ratio
  • water supply

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Plant Science

Fingerprint Dive into the research topics of 'Responses of leaf C:N:P stoichiometry to water supply in the desert shrub Zygophyllum xanthoxylum'. Together they form a unique fingerprint.

  • Cite this