Vargas et al. 2015 (Conference Paper) Neoregelia, leaf

Plasticity of leaf anatomy in the nurse-plant bromeliad Neoregelia cruenta

Author(s):—Pedro da Silva Vargas, Isabelle Soares Pepe, Ginayan de Souza Silveira, Hugo Dolsan Freitas & Dulce Gilson. Mantuano in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—Neoregelia cruenta (R. Graham) L.B. Smith (Bromeliaceae) is a CAM tank bromeliad, endemic of southeast ?restinga?, i.e., the open scrub vegetation of Brazilian coastal plains. At this location N. cruenta increases diversity acting as nurse-plant. Clonal reproduction is a common feature in herbaceous plants and has been shown to be important for recruitment and population maintenance in this species. N. cruenta populationsare subject to different levels of light exposure depending on the individual position related to vegetation clumps. Connected ramets are subjected to three microhabitats: (i) exposed to full irradiance, outside vegetation islands; (ii) partially exposed to full irradiance, at the border of vegetation islands; (iii) shaded, inside vegetation islands. We examined the environmental effect on leaf anatomy of N. cruenta both within ramets connected in clonal clumps (intraclonal variation) and among clones (interclonal variation). Leaves of two connected ramets of five replicas in each microhabitat were sampled. Anatomical parameters were thickness of leaf blade, thickness of chlorenchyma, thickness and number of layers of water-storage parenchyma,thickness of adaxial and abaxial epidermis, density and position of trichomes, and stomatal density. All leaves of N. cruenta shared the same anatomical features irrespective of microhabitat. Thicker water-storage parenchyma and leaf blades were found on both connected ramets in exposed microhabitat and the exposed ramet of partially exposed microhabitat, related to the shorter time of tank water storage. Intraclonal variation was statistically significant only at the partially exposed microhabitat. Both phenotypic plasticity within connected ramets and genetic variation among connected ramets might help to explain the high abundance of N. cruenta along heterogeneous environment of ?restinga? vegetation.

Keywords:—Plasticity; Nurse-plant; Neoregelia cruenta.