Loss of desiccation tolerance during germination in neo-tropical pioneer seeds: Implications for seed mortality and germination characteristics

Matthew I. Daws, Sheina Bolton, David F. R. P. Burslem, Nancy C. Garwood, Christopher E. Mullins

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

Orthodox, desiccation-tolerant seeds lose desiccation tolerance during germination. Here, we quantify the timing of the loss of desiccation tolerance, and explore the implications of this event for seed mortality and the shape of germination progress curves for pioneer tree species. For the nine species studied, all seeds in a seedlot lost desiccation tolerance after the same fixed proportion of their time to germination, and this proportion was fairly constant across the species (0.63-0.70). The loss of desiccation tolerance after a fixed proportion of the time to germination has the implication that the maximum number of seeds in a seedlot that can be killed by a single drying event during germination (M-max) increases with an increasing time to 50% germination (t(50)) and an increasing slope of the germination progress curve. Consequently, to prevent the seed population from becoming highly vulnerable to desiccation-induced mortality, species with a greater t(50) would be expected to have a shallower germination progress curve. In conclusion, these data suggest that the loss of desiccation tolerance during germination may constitute a significant, but previously unexplored, source of mortality for seeds in seasonal environments with unpredictable rainfall.

Original languageEnglish
Pages (from-to)273-281
Number of pages9
JournalSeed Science Research
Volume17
Issue number4
DOIs
Publication statusPublished - 2007

Keywords

  • desiccation tolerance
  • germination rate
  • Panama
  • seed mortality
  • tropical forest
  • topographic position
  • trees
  • size
  • ecophysiology
  • survival
  • responses
  • seedlings
  • growth

Cite this