Pollination strategies of Berberis microphylla G. Forst, a Patagonian barberry

Abstract

Calafate (Berberis microphylla G. Forst) is a spontaneous shrub of Patagonia. Fruits are black-blue berries rich in antioxidant compounds such as flavonols and anthocyanins. Blooming occurs in spring and flowers at anthesis show bright yellow sepals and petals, a receptive stigma, non-dehiscent anthers and high nectar production that results in a pleasant aroma. Like all the species of the genus Berberis the stamens are retractable, and dehiscence occurs after mechanical stimulation. The objective of this study was to understand the different mechanisms developed to achieve effective flower pollination. Thus, floral offering was quantified at full bloom, and anther movement, nectar production, sugar concentration and interaction with visitor insects were studied in detail.