Occurrence of physical dormancy in seeds of Australian Sapindaceae: A survey of 14 species in nine genera
MetadataShow full item record
• Background and Aims: Sapindaceae is one of 16 angiosperm families whose seeds have physical dormancy (PY). However, the extent and nature of PY within this family is poorly known. The primary aims of this study were: (1) to evaluate seed characteristics and determine presence (or not) of PY within nine genera of Australian Sapindaceae; and (2) to compare the frequency of PY across the phylogenetic tree within Australian Sapindaceae. • Methods: Viability, imbibition and seed characteristics were assessed for 14 taxa from nine genera of Sapindaceae. For five species of Dodonaea, optimal conditions for germination and dormancy break were evaluated. An in situ burial experiment was performed on D. hackettiana seeds to identify the factor(s) responsible for overcoming PY. Classes of dormancy and of non-dormancy for 26 genera of Sapindaceae were mapped onto a phylogenetic tree for the family. • Key Results: Mean seed viability across all taxa was 69.7 %. Embryos were fully developed and folded (seven genera) or bent (two genera); no endosperm was present. Seeds of all five Dodonaea spp. and of Distichostemon hispidulus had PY. Hot-water treatment released PY in these six species. Optimal germination temperature for seeds of the four Dodonaea spp. that germinated was 15-20°C. Following 5 months burial in soil, 36.4 % of D. hackettiana seeds had lost PY and germinated by the beginning of the winter wet season (May). Laboratory and field data indicate that dormancy was broken by warm, moist temperatures (=50°C) during summer. • Conclusions: PY occurs infrequently in genera of Sapindaceae native to Australia. Seeds of Dodonaea and Distichostemon had PY, whereas those of the other seven genera did not. Seeds of these two genera and of Diplopeltis (a previous study) are the only three of the 20 native Australian genera of Sapindaceae for which germination has been studied that have PY; all three belong to subfamily Dodonaeoideae. © The Author 2008. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.
Showing items related by title, author, creator and subject.
Identification and characterization of the water gap in the physically dormant seeds of Dodonaea petiolaris: A first report for SapindaceaeTurner, S.; Cook, A.; Baskin, J.; Baskin, C.; Tuckett, R.; Steadman, K.; Dixon, Kingsley (2009)Background and AimsThe Sapindaceae is one of 17 plant families in which seed dormancy is caused by a water-impermeable seed or fruit coat (physical dormancy, PY). However, until now the water gap in Sapindaceae had not ...
Seed Treatment Optimizes Benefits of Seed Bank Storage for Restoration-Ready Seeds: The Feasibility of Prestorage Dormancy Alleviation for Mine-Site RevegetationTurner, S.; Steadman, K.; Vlahos, S.; Koch, J.; Dixon, Kingsley (2013)Dormant seeds of 18 species from 9 families covering a diverse range of seed dormancy syndromes and life histories from the southwest Australian biodiversity hotspot were assessed for germinability following storage at ...
Increasing the germination envelope under water stress improves seedling emergence in two dominant grass species across different pulse rainfall eventsLewandrowski, W.; Erickson, T.; Dixon, Kingsley; Stevens, J. (2016)Demographic recruitment processes, such as seed germination and seedling emergence, are critical transitional phases to the re-establishment of degraded plant populations, but often fail due to rainfall not supporting ...