Nectar and the pollination of bread fruit, Artocarpus altilis (Moraceae)

In Cameta, PA, Brasil, Trigona (Trigona) fulviventris var. guianae Cock, bees collect pollen and presumably also nectar from staminate inflorescences of Artocarpus altilis (Park.) Fosberg (= A. communis = A. incisa). In this tree the production of staminate inflorescences alternates with that of pistillate ones (second-order dichogamy). Pistillate inflorescences do not produce any nectar. Microtechnical and anatomical studies confirmed the nectar production from morphologically unspecialized cells in the perianth bases. The nectar is secreted through stomata into the interfloral spaces. This primitive mode of secretion might be an indication of a novel development rather than a rudimentary character. Its adaptive value remains uncertain. The relevance of this nectar production is discussed in the light of conflicting views about the evolutionarily oldest mode of pollination in the Moraceae: anemophily or zoophily?