Document: CLA-3-42-43

Herbivore damages to floral structures in three species of Vellozia (Velloziaceae) in SE Brazil.

JACOBI, C.M.* and A.C.BARBOSA

Universidade Federal de Minas Gerais, Belo Horizonte, MG, 30161, Brazil ¹

Abstract:
The effect of damages to floral structures was assessed in three species of Vellozia (Velloziaceae). V. leptopetala, V. epidendroides and V. caruncularis are shrubby plants well adapted to "campos rupestres", an arid montane biome in SE Brazil characterized by high endemism, poor quartzitic soils and frequent fires. All are highly self-incompatible, and the populations rely on a synchronous, 'cornucopia'-type floral display to attract pollinators (mainly bees and hummingbirds), which attracts herbivores as well. Observations of buds, flowers and young fruits were made in the field during the short flowering period of each species. Dry fruits (capsules) were collected and examined at the laboratory. Buds were attacked mainly by flea beetles. Also, bees forced their way into older buds and removed pollen before the stigma was receptive. The most common florivores were Acrididae, Tettigoniidae and several species of ants. Damages to flowers were high: 39% in V. leptopetala (n=211), 50% in V. epidendroides (n=688) and 53% in V. caruncularis (n=139). Anthers were the most predated structures (22-48%), followed by petals, ovary, stigma and frequently a combination of these categories. Partial or, most commonly, complete destruction of the young ovary and ovule or seed mass was effected mainly by dipteran larvae or by adult beetles, Chrysomelidae and Curculionidae. The 'cornucopia' pattern may be viewed as a way to grant seed production by letting some flowers escape from predation.

Keywords:

This abstract is being presented at: 3:30 PM in session:
HERBIVORE EFFECTS ON PLANTS