Water loss from flower heads predicts seed release in two invasive thistles

Katherine M. Marchetto, Eelke Jongejans, Katriona Shea, Richard Auhl

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Background: Non-random seed release caused by plant responses to weather conditions is important for seed dispersal. Much is known about the effects of wind speed and turbulence, but our understanding of the effects of water loss on seed release is either qualitative, or indirect and phenomenological.Aims: To quantify the empirical relationship between water loss and seed release.Methods: Capitula of the invasive thistles Carduus acanthoides and C. nutans were collected from the field and treated for either 0, 1 or 2 days in the laboratory at three different vapour pressure deficit levels (3.4, 9.5 and 17.0 hPa) to cause a range of water loss values. Total seed release was quantified before and during wind tunnel trials.Results: Water loss was the only significant predictor of whether or not capitula released any seeds. The number of seeds released was predicted by water loss, capitulum diameter and herbivore damage, with the same amount of water loss having less effect on larger capitula.Conclusions: These results represent an important step towards using weather data to predict seed release for many xerochastic species. Incorporating the effects of water loss on seed release into mechanistic seed dispersal models will greatly improve predictions of when and how far seeds disperse.

Original languageEnglish (US)
Pages (from-to)57-65
Number of pages9
JournalPlant Ecology and Diversity
Issue number1
StatePublished - Mar 2012

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Plant Science


Dive into the research topics of 'Water loss from flower heads predicts seed release in two invasive thistles'. Together they form a unique fingerprint.

Cite this