Stephanie Cruz-Maysonet, 2010

University of Puerto Rico Bayamon

Does a shift to small flowers in annual groundcherries leave specialist pollinators behind?

The acquisition of an autogamous mating system has been linked to various floral traits. These include reduced flowers, short styles, small pollen, and small pollen-ovule ratios. Self-pollination has also been linked to the annual growth habit. This study looked at floral morphology (flower size, anther-stigma distance), nectar production, self-compatibility and interactions with pollinators in a common garden environment for five Physalis species (two perennials and three annuals). While significant reduction of flower size (P<0.001), little stigma-anther distance, and lower pollen amounts supported our hypothesis for the annuals, nectar volume and sucrose concentration were unexpectedly similar across species. This may explain why levels of visitation are similar for perennials and annuals, too. High fruit set (62-77%) for annuals, in the absence of pollinators, allows us to conclude these species are self compatible and self pollinating.

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