Abelhas visitantes florais e potenciais polinizadores da cajazeira (Spondias mombin L.) sob cultivo, na Chapada do Apodi, Ceará

Abstract

The research was carried out from November of 2009 to January of 2010, in the Apodi plateau, situated in the county of Limoeiro do Norte, state of Ceará. It was used 32 cajazeira trees (Spondias mombim L.) of the Lagoa Redonda cloning tree, grafted on the umbuzeiro tree (Spondias tuberose A.). The objective was to verify some variables regarding to floral biology; foraging pattern; abundance and frequency of floral visitors, mainly bees, of the cajazeira tree during the blooming season. It was also observed the initial fruit set for each pollination test (open pollination; restricted pollination with a paper pollination bag; restricted with a tulle pollination bag; hand cross pollination with pollen from males flowers; hand cross with pollen from hermaphrodite flowers; autopollination and pollination by honeybee, Apis mellifera and stingless bee, Trigona spinipes). The results showed that the main and most abundant floral visitors of the cajazeira tree were A. mellifera (68%) followed by T. spnipes (30%), Xylocopa grisescens (1%) and Plebeia aff. Flavocincta (1%). Although the cajazeira tree presents high production of flowers, the levels of open pollination are below to its potential of setting fruits, when compared with the hand cross-pollination and with the pollination by Apis mellifera. The flowers of cajajeira tree are unable to do self-pollination, thus requiring the participation of abiotic agents, in this case the wind, and/or biotic agents like bees, to promote their pollination. It is concluded that the cajazeira tree, is an andromonoecious, and allogamous species which produces high amount of pollen, and presents a melittophilous pollination syndrome whose the species Apis mellifera, Trigona spinipes and Xylocopa grisecens are its effective pollinators. Among them, Apis mellifera was the main, and the most efficient pollinator, which improved the initial fruit set on the Lagoa Redonda cloning tree, under cultivation conditions, in the Apodi plateau, state of Ceará.