Seed ageing and smoke: partner cues in the amelioration of seed dormancy in selected Australian native species.

摘要

Seed germination of many Australian native plant species has consistently proven to be fractious. With the discovery of smoke-mediated germination, it is now possible to better understand the heterogeneity in germination patterns for a wide range ofspecies both in situ and ex situ. In the present study, over 180 species were examined as to viability and smoke responsiveness of freshly collected seeds. Soil storage and a number of commonly used seed pre-treatments were employed in combination withsmoke to examine both longevity in artificially constructed seed banks, and the role of seed aging in improved germination. Methods of smoke application for commercial use were also investigated. Viability decline over 1 year varied between 10% and 80%.Reductions of as little as 15% were found to compromise the ability of a number of species to successfully recruit in consecutive seasons. When fresh seeds were used, almost 70% of species tested responded positively to smoke whether applied prior to orafter sowing. Variation in success between the two methods confirmed earlier conclusions that substances contained in plant-derived smoke may be inhibitory at high concentrations for particularly sensitive species. Only 10% of species under investigationrecorded optimum germination with seed aging alone but when smoke was applied as a treatment after soil storage, 60% of species responded positively. Implications for horticulture, rehabilitation, seed bank research and habitat management are discussed.