Drought stress and fluctuating asymmetry in Quercus undulata leaves: Confounding effects of absolute and relative amounts of stress?

J. M. Fair, D. D. Breshears

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

One of the most general types of stress experienced by plants is water-limitation, which becomes particularly pronounced during periods of drought. We evaluated fluctuating asymmetry (FA) in Quercus undulata leaves for two subsequent dry years: 2001, when precipitation was 25% below average, and 2002, when precipitation was 65% below average, from a plot receiving ambient water and one in which water was excluded. In the first and less severe drought year, ambient-water trees had a slightly higher index of FA than the water-exclusion trees, contrary to expectations. However, in the second and much more extreme drought year, water-exclusion trees exhibited greater FA as expected, but in additional observations water-supplement trees exhibited by far the greatest amount of FA, contrary to expected. Further data on plant water potential confirmed that degree of plant stress corresponded to plot treatments: water exclusion>ambient water>water supplement. Stable carbon isotope ratios indicated that trees on the water-supplement plots were less stressed than ambient-water and water-exclusion trees, and leaf size was much greater for water-supplement trees than ambient-water or water-exclusion trees. We hypothesize that the complexity of the results could be due to the confounding effects of relative vs. absolute stress.

Original languageEnglish (US)
Pages (from-to)235-249
Number of pages15
JournalJournal of Arid Environments
Volume62
Issue number2
DOIs
StatePublished - Jul 2005

Keywords

  • Growth
  • Leaves
  • Water-limitation
  • Wavyleaf oak

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Earth-Surface Processes

Fingerprint Dive into the research topics of 'Drought stress and fluctuating asymmetry in Quercus undulata leaves: Confounding effects of absolute and relative amounts of stress?'. Together they form a unique fingerprint.

  • Cite this