Pollination Biology
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Title
Pollination Biology
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Authors
Scott Alan Mori
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Description
The flowers of the Brazil nut are zygomorphic, with an androecium that is prolonged on one side into a hood that arches over and is tightly appressed to the summit of the ovary. In addition, the petals are appressed to the androecium (Fig. 27-1). Consequently, the flowers can only be entered by large-bodied bees with enough strength to pry open the androecial hood to obtain the pollinator reward that is thought to be nectar produced at the apex of the coiled androecial hood. Bees of the genera
have been captured visiting Brazil nut trees (Moritz, 1984; Müller et al., 1980; Nelson et al., 1985). These bees are nonsocial or semi-social and therefore do not lend themselves easily to manipulation by humans, such as is the case with the social bees (for example, ) that can be used to pollinate certain crops by transporting beehives from one plantation to the next. For the most part, cross-pollination is needed for seed set in Neotropical Lecythidaceae. Therefore, the bees, and to a lesser extent bats, are essential for the pollination and subsequent fruit and seed development of Lecythidaceae. Although a low level of in-breeding may occur in , most seed set in this species is the result of cross-pollination (Mori and Prance, 1990b). The development of self-compatible lines of the Brazil nut would facilitate plantation cultivation of this species by eliminating the need for cross-pollination by the difficult to manage bee pollinators. Bees outside of the native range of the Brazil nut can effect pollination. For example, Brazil nut trees in Ceylon (Macmillan, 1935), Kuala Lumpur, and Ghana set fruit. However, it is not known if pollinators outside of the native range of the Brazil nut or "weedy" pollinators found in secondary forests are efficient enough to allow for economically viable fruit production.