Testing the regeneration niche hypothesis with Gesneriaceae (tribe Sinningiae) in Brazil: Implications for the conservation of rare species
Article first published online: 27 APR 2011
© 2011 The Authors. Journal compilation © 2011 Ecological Society of Australia
Volume 37, Issue 1, pages 125–133, February 2012
How to Cite
RANIERI, B. D., PEZZINI, F. F., GARCIA, Q. S., CHAUTEMS, A. and FRANÇA, M. G. C. (2012), Testing the regeneration niche hypothesis with Gesneriaceae (tribe Sinningiae) in Brazil: Implications for the conservation of rare species. Austral Ecology, 37: 125–133. doi: 10.1111/j.1442-9993.2011.02254.x
- Issue published online: 30 JAN 2012
- Article first published online: 27 APR 2011
- Accepted for publication February 2011.
- Atlantic Forest;
- rocky outcrop;
- threatened species
The germination requirements of sexually reproducing plants are regulated by environmental factors such as temperature. Those factors acting at the germination phase are part of the regeneration niche, which is fundamental in the processes that contribute to habitat suitability and geographic distribution. We tested the hypothesis that rarity is associated with regeneration niche in three species of plants in the family Gesneriaceae (tribe Sinningieae), Sinningia rupicola (Mart.) Wiehler, Paliavana sericiflora Benth and Sinningia allagophylla (Mart.) Wiehler, which vary in their distribution and habitat specificity but share a small zone of sympatry in rocky fields south of Belo Horizonte in Minas Gerais, Brazil. The regeneration niche was tested using a seed germination experiment under controlled light conditions at seven fixed temperatures (10–40°C at 5°C intervals). Each of the three species germinated differently at the various temperatures. The species with the smallest geographic range, S. rupicola, also had the most restricted germination: germination peaked at 15°C when relatively few seeds germinated (45%), and even fewer germinated at other temperatures. The regeneration niche was wider in P. sericiflora and wider still in S. allagophylla, with germination greater than 90% between 15–25°C and greater than 80% between 15–30°C, respectively. Our germination results provide qualified support for the hypothesis of correlation of the regeneration niche with geographic distribution of related plant taxa, with important conservation implications for rare and endangered species.