Influence of sex‐organ positions on pollen transfer and self‐interference in plants with stylar polymorphisms: An experimental approach using three‐dimensional printed flowers
[EN] Heterostylous plants are defined by the reciprocal positioning of stigmas and anthers in floral morphs—a trait proposed by Darwin to enhance the efficiency of disassortative (intermorph) pollen transfer. This floral polymorphism may also reduce gamete wastage by minimizing sexual interference b...
| Autores: | , , , |
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| Tipo de documento: | artigo |
| Estado: | Versão publicada |
| Data de publicação: | 2025 |
| País: | España |
| Recursos: | Universidad de León |
| Repositório: | BULERIA. Repositorio Institucional de la Universidad de León |
| OAI Identifier: | oai:buleria.unileon.es:10612/27164 |
| Acesso em linha: | https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2435.70104 https://hdl.handle.net/10612/27164 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Biología Botánica Artificial flowers Bombus impatiens Disassortative pollination Heterostyly Self-interference Stylar polymorphisms 2417 Biología Vegetal (Botánica) 3107.03 Floricultura |
| Resumo: | [EN] Heterostylous plants are defined by the reciprocal positioning of stigmas and anthers in floral morphs—a trait proposed by Darwin to enhance the efficiency of disassortative (intermorph) pollen transfer. This floral polymorphism may also reduce gamete wastage by minimizing sexual interference between male and female reproductive organs. In distylous species, two floral morphs occur: a long-styled morph with stigmas positioned above the anthers and a short-styled morph with stigmas below the anthers. A related floral polymorphism, known as stigma-height dimorphism, involves variation in stigma height but not anther placement. To test how floral architecture influences pollen transfer and reproductive interference, we used 3D-printed artificial flowers based on Petunia grandiflora, incorporating real styles and anthers from glasshouse-grown plants. These artificial flowers simulated distyly and two forms of stigma-height dimorphism. In flight cage experiments, captive bumblebees (Bombus impatiens) from commercial colonies facilitated pollen transfer within and between flowers. We measured pollen grain deposition on stigmas and styles, as well as residual pollen in donor anthers. Our results provided partial support for Darwin's hypothesis: in distylous arrays, reciprocal sex-organ placement enhanced intermorph pollen deposition, especially in the short-styled morph. Bumblebee foraging time influenced pollen load, with longer visits to long-styled flowers resulting in increased pollen deposition. Patterns of self-pollen deposition—a form of reproductive interference—varied with the degree of spatial separation between sexual organs. As expected, stigma-height dimorphic arrays exhibited higher self-pollen transfer than distylous arrays. While not conclusive, our findings emphasize the role of floral morphology in shaping pollination dispersal, self-interference and pollinator behaviour. The use of three-dimensional printed flowers demonstrates a promising experimental approach for future studies on plant–pollinator interactions and the functional significance of floral design. Read the free Plain Language Summary for this article on the Journal blog |
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