continental-scale study of seed lifespan in experimental storage examining seed, plant, and environmental traits associated with longevity

• Published in: Biodiversity and conservation Vol. 23; no. 5; pp. 1081 - 1104
• Main Authors: Merritt, David J, Martyn, Amelia J, Ainsley, Phillip, Young, Renee E, Seed, Leahwyn U, Thorpe, Michael, Hay, Fiona R, Commander, Lucy E, Shackelford, Nancy, Offord, Catherine A, Dixon, Kingsley W, Probert, Robin J
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.05.2014; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: Analysis; Animal and plant ecology; Animal, plant and microbial ecology; Applied ecology; Australia; Biodiversity; Biological and medical sciences; Biological diversity conservation; Biomedical and Life Sciences; Climate Change/Climate Change Impacts; Conservation biology; Conservation Biology/Ecology; Conservation, protection and management of environment and wildlife; dormancy; Ecology; endosperm; Environmental factors; Flora; Fundamental and applied biological sciences. Psychology; General aspects; Germination; Life Sciences; Longevity; Original Paper; Phylogenetics; Plant ecology; probit analysis; rain; Seed banks; Seeds; shrubs; Species diversity; Synecology; temperature; trees; viability; Australia; Biodiversity conservation; Climate; Seed bank; Germination; Gene bank; Serotiny; Seeds; Environmental factor; Longevity; Biodiversity; Experimental study; Storage; Environment; Environmental protection
• ISSN: 0960-3115; 1572-9710
• DOI: 10.1007/s10531-014-0641-6

Management of seed banks conserving the biodiversity of phylogenetically diverse species requires insight into seed longevity. This study determined the seed longevity of 172 species sourced from across the mega-diverse flora of the Australia continent. Seeds were aged via a controlled ageing experiment through storage at 45 °C and 60 % RH, or 60 °C and 60 % RH, and regularly tested for germination. Relative seed longevity between species was determined by comparing the time to 50 % viability loss (p ₅₀), calculated via probit analysis of seed survival curves. Seed, plant, and environmental traits were examined for associations with longevity. The p ₅₀ values varied between species from 3.0 to 588.6 days. Serotinous species, and woody trees and shrubs, had significantly longer-lived seeds than geosporous species, and species of herbaceous habit. Seeds that possess physical dormancy, and seeds with large embryos with little endosperm, were also long-lived. There was a weak, but significant, positive correlation between seed mass and longevity. Seeds sourced from regions of higher mean annual temperature and rainfall were significantly longer-lived than seeds from cooler and drier regions, although both environmental factors were weakly associated with longevity. Compared with species from other regions of the world, prolonged longevity is a feature of many Australian species. Nevertheless, seed life-spans vary substantially between species and close consideration of seed traits along with biotic and abiotic components of the plants and their environment can assist to differentiate between potentially long- and short-lived seeds.