I’ve been robbed! – Can changes in floral traits discourage bee pollination?

Autoři: Camila Vaz de Souza aff001;  Maíra Vidor Salvador aff002;  Priscila Tunes aff001;  Luiz Claudio Di Stasi aff003;  Elza Guimarães aff004
Působiště autorů: Graduation Program in Biological Sciences, Laboratory of Ecology and Evolution of Plant-Animal Interactions, Department of Botany, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil aff001;  Undergraduate Course in Biological Sciences, Laboratory of Ecology and Evolution of Plant-Animal Interactions, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil aff002;  Laboratory of Phytomedicine, Pharmacology and Biotechnology, Department of Pharmacology, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil aff003;  Laboratory of Ecology and Evolution of Plant-Animal Interactions, Department of Botany, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil aff004
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225252


Some floral visitors collect nectar by piercing flower external whorls, acting as nectar robbers. They leave robbery vestiges, which can cause changes in floral characteristics, including physical and chemical signals that may influence flower recognition by pollinators. If pollinating bees associate these changes with absence or reduction in nectar volume, they can avoid these flowers, negatively affecting pollination. We aimed to investigate the effect of robbery on primary and secondary attractants. Additionally, we experimentally investigated if the visual signs present in robbed flowers affect the bee pollination of this plant species by discouraging pollinator visits. This study was performed in a very common pollinator-plant-cheaters system comprised by a bee-pollinated Bignoniaceae species and a nectar-robber bee that lands on the corolla tube and makes slits at its base during the nectar robbery. We experimentally isolated the effect of nectar consumption by this nectar-robber and investigated if the slits caused by the nectar-robbers affected the floral scent emission. In addition, we experimentally evaluated the effect of visual signs (slits) associated to the nectar robbery and the effect of nectar depletion on the pollination of Jacaranda caroba (Bignoniaceae). The robbers visited around 75% of the flowers throughout the day and removed significant amounts of nectar from them. However, the damages the robbers cause did not affect floral scent emission and we did not verify significant differences on pollen deposition neither when comparing flowers with slits and control nor when comparing flowers with and without nectar. We showed that even though nectar-robbers visually honestly signal the robbery and deplete high amounts of nectar, they did not affect pollinator visitation. These results showed that presumably antagonistic interactions might in fact not be so.

Klíčová slova:

Bees – Corolla – Flowering plants – Flowers – Pollen – Pollination – Visual signals – Stigma


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Článek vyšel v časopise


2019 Číslo 11