Dispersão, fenologia e conservação de Annona crassiflora Mart. (Annonaceae)

Abstract

Annona crassiflora Mart. Annonaceae, locally called araticum or marolo) is an important component of Cerrado canopy and belongs to a genus that is both ecologically important and commercially valuable. Data collection was done in a private ranch in Carmo da Cachoeira, South of Minas Gerais. The study area was originally cerrado, but today is a silvopastoral system with marolo and Brachiaria decumbens. In this thesis, we follow 50 fruits of marolo, after natural dispersion (barochory), to identify the seed disperser; we monitor both reproductive and vegetative phenology, including pollination test. Seeds were buried from the fallen fruit, together with the pulp, by dung beetle species related to Dichotomius aff. Ascanius. The species show a bimodal flowering behaviour during the year. This phenomenon could be explained by the center of origin of the Annonaceae and the selective force toward to maintain the population of pollinator and guarantee the pollination service. The pollination tests showed that fruit set can be improved by hand cross-pollination. Other possible way to improve the fruit set is to enhance natural pollination by reducing the intensity of animal grazing, preserving natural forests and forest fragments in the vicinity of the agroforestry system, and reintroducing A. coriacea, A. dioica, A. monticola, co-occurring species also pollinated by the dynastine scarab beetles, Cyclocephala atricapilla.