Fire-stimulated flowering among resprouters and geophytes in Australia and South Africa
MetadataShow full item record
Data on 386 species with fire-stimulated flowering (fsf) in Australasia and South Africa/Madagascar were collated to show that they occur under a wide range of fire regimes, with 71% confined to the mediterranean-climate regions. About 40% only flower up to 2 years after fire (obligate), while the rest continue at a low rate until the next fire (facultative). Peak flowering occurs 5–18 months after fire in the mediterranean regions but at 1–7 months in savannas. Fsf is recorded in 34 families, headed by terrestrial orchids (45% of species), spread throughout the seed-plant phylogeny from cycads to daisies. Tuberous geophytes (essentially orchids) dominate (51%), but other resprouting growth forms include lignotuberous shrubs and forbs, rhizomatous and bunch grasses, leaf succulents, grasstrees, epicormic trees, and hemiparasites. Most have wind-dispersed diaspores (72%), store their diaspores in the soil (93%), and seeds that do not germinate until the next fire (72%). Fsf in association with resprouting takes advantage of optimal resources and minimal competition for growth and reproduction, conditions that favor wind dispersal and maximize the interval for seed accumulation before the next fire and build-up of fire-tolerant organs.Reduced herbivory has little role in accounting for its benefits. The proximal causes of fsf center around cueing factors (direct effects such as ethylene), resource factors (direct and indirect effects, e.g., extra nutrients), and predisposing factors (circumstantial effects, e.g., fire interval). The evolutionary history of fsf has been explored recently in orchids, proteas, blood roots, droseras, and mistletoes and shown to stretch back over a period of at least 50 million years, indicating that flowering in many groups has a long association with fire as an agent of natural selection.
Showing items related by title, author, creator and subject.
Lamont, Byron; He, Tianhua; Yan, Z. (2018)Fire has shaped the evolution of many plant traits in fire-prone environments: fire-resistant tissues with heat-insulated meristems, post-fire resprouting or fire-killed but regenerating from stored seeds, fire-stimulated ...
Orchid re-introductions: an evaluation of success and ecological considerations using key comparative studies from AustraliaReiter, N.; Whitfield, J.; Pollard, G.; Bedggood, W.; Argall, M.; Dixon, Kingsley; Davis, B.; Swarts, N. (2016)With global biodiversity in decline, there is now an urgent requirement to take ameliorative action for endangered species in the form of reintroductions. For the highly diverse orchid family, many species face imminent ...
Lamont, Byron; Enright, Neal; Witkowski, E.; Groeneveld, J. (2007)We have studied the ecology and conservation requirements of Banksia species in the species-rich sandplains of south-western Australia for 25 years. Loss of habitat through land-clearing has had the greatest impact on ...