Multifunctional bracts in the dove tree Davidia involucrata (Nyssaceae: Cornales): Rain protection and pollinator attraction

Ji Fan Sun, Yan Bing Gong, Susanne S. Renner, Shuang Quan Huang

Research output: Contribution to journalArticlepeer-review

71 Scopus citations

Abstract

Although there has been much experimental work on floral traits that are under selection from mutualists and antagonists, selection by abiotic environmental factors on flowers has been largely ignored. Here we test whether pollen susceptibility to rain damage could have played a role in the evolution of the reproductive architecture of Davidia involucrata, an endemic in the mountains of western China. Flowers in this tree species lack a perianth and are arranged in capitula surrounded by large (up to 10 cm x 5 cm) bracts that at anthesis turn from green to white, losing their photosynthetic capability. Flowers are nectarless, and pollen grains are presented on the recurved anther walls for 5-7 days. Flower visitors, and likely pollinators, were mainly pollen-collecting bees from the genera Apis, Xylocopa, Halictus, and Lasioglossum. Capitula with natural or white paper bracts attracted significantly more bees per hour than capitula that had their bracts removed or replaced by green paper. Experimental immersion of pollen grains in water resulted in rapid loss of viability, and capitula with bracts lost less pollen to rain than did capitula that had their bracts removed, suggesting that the bracts protect the pollen from rain damage as well as attracting pollinators.

Original languageEnglish
Pages (from-to)119-124
Number of pages6
JournalAmerican Naturalist
Volume171
Issue number1
DOIs
StatePublished - Jan 2008

Keywords

  • Abiotic selection
  • Davidia involucrata
  • Inflorescence architecture
  • Pollen protection
  • Pollen viability
  • Pollinator attraction

Fingerprint

Dive into the research topics of 'Multifunctional bracts in the dove tree Davidia involucrata (Nyssaceae: Cornales): Rain protection and pollinator attraction'. Together they form a unique fingerprint.

Cite this