Acta Botanica Brasilica
versão impressa ISSN 0102-3306
CONCEICAO, Abel Augusto e ORR, Barron J.. Post-fire flowering and fruiting in Vellozia sincorana, a caulescent rosette plant endemic to Northeast Brazil. Acta Bot. Bras. [online]. 2012, vol.26, n.1, pp. 94-100. ISSN 0102-3306. http://dx.doi.org/10.1590/S0102-33062012000100011.
Vellozia sincorana L.B. Sm. & Ayensu, an endemic of campos rupestres, is an endangered species collected by local people to start cooking fires due to the flammability of its resinous stems. A massive flowering of V. sincorana following a wildfire in October 1999 raised some questions: Does fire affect flowering and fruiting of V. sincorana? Is the height of individuals correlated with flowering and fruit production? A wildfire event on 8 November 2008 provided an opportunity to explore these questions. Two populations of V. sincorana in two campos rupestres sites (12º31'S - 41º29'W; 12º36'S - 41º28'W) on ridgetops in the Chapada Diamantina National Park (Brazil) were monitored, one burned in the November 2008 fire and the other unburned since the 1999 fire. In both sites, 25 individuals were randomly labeled and monitored. Nine plant samplings were conducted between 2008 and 2010, during which the number of flowers and fruits were tallied and the heights measured. Spearman's rank correlation coefficient and linear regression were used to evaluate the relationship between the height of individuals and phenology. Flowering and fruiting occurred only in the recently burnt population, about 40 days after the fire, in 24 of the 25 individuals monitored (96%). The quantity of flower and/or fruit was positively and significantly correlated with plant height. The abundant flowering after fire suggests that fire triggers this phenological phase. Estimates of age of the taller individuals and the periods of flowering can be used to estimate fire frequency in the V. sincorana population sites, which contributes to the knowledge of fire ecology and is useful for conservation biology and fire management of campos rupestres.
Palavras-chave : Chapada Diamantina; phenology; rupestrian fields; useful plant; Velloziaceae.