Smoke stimulates germination in two divergent Gondwanan species (Hibbertiapancheri and Scaevola montana) endemic to the biodiversity hotspot of New Caledonia

Abstract

AbstractDue to shared geological history and proximity, the flora of New Caledonia is closely linked to other Gondwanan land fragments such as Australia and New Zealand. Many predominant Australian groups are well represented within the New Caledonian flora, including the genera Hibbertia (23 species) and Scaevola (10 species). Previous studies have found that these two genera in particular have a marked positive germination response to smoke products, although all previous studies have centred on Australian species from fire-prone environments. In this present study, we test the hypothesis that two New Caledonian species of Hibbertia and Scaevola are smoke responsive even though the climate and ecological drivers in New Caledonia are in many respects fundamentally different from those of most of Australia. Preliminary results showed that germination of Hibbertia pancheri was significantly accelerated in response to smoke water while germination in Scaevola montana was also significantly enhanced. To the best of our knowledge, this is the first time that these trends have been illustrated for any New Caledonian species and these results will enhance restoration efforts of ultramafic scrublands impacted by mining activities in New Caledonia.