Abstract
AbstractFlorivory, or the consumption of flowers, is a ubiquitous interaction that can reduce plant reproduction directly by damaging reproductive tissues and indirectly by deterring pollinators. However, we know surprisingly little about how florivory alters plant traits or the larger community of species interactions. Although leaf damage is known to affect floral traits and interactions in many systems, the consequences of floral damage for leaf traits and interactions are unknown. We manipulated floral damage in Impatiens capensis and measured effects on floral attractive traits and secondary chemicals, leaf secondary chemicals, floral interactions, leaf herbivory, and plant reproduction. We also examined relationships between early season floral traits and floral interactions, to explore which traits structure floral interactions. Moderate but not high florivory significantly increased relative selfed reproduction, leading to a shift in mating system away from outcrossing. Florivory increased leaf secondary compounds and decreased leaf herbivory, although mechanisms other than leaf chemistry may be responsible for some of the reduced leaf damage. Florivory altered four of seven measured interactions, including increased subsequent florivory and reduced flower spiders, although only leaf damage effects were significant after correcting for multiple tests. Pretreatment concentrations of floral anthocyanins and condensed tannins were associated with reduced levels of many floral antagonisms, including florivory, nectar larceny, and flower spider abundance, suggesting these traits play a role in floral resistance. Overall, our results indicate a broad range of community and potential evolutionary consequences of florivory through structuring subsequent floral interactions, altering leaf secondary chemicals, and shaping leaf herbivory.
Highlights
While the role of pollinators in the evolution of floral diversity is well recognized (e.g., Fenster et al 2004), there are many antagonists that are attracted to flowers and can shape selection on floral traits
We found that floral damage affected offspring quality and had far- reaching consequences, shaping traits and structuring interactions in both leaves and flowers
In Massachusetts, I. capensis generally germinates in late April or early May, CL flowers appear in May, and CH flowers last from mid-July until mid-September
Summary
While the role of pollinators in the evolution of floral diversity is well recognized (e.g., Fenster et al 2004), there are many antagonists that are attracted to flowers and can shape selection on floral traits. The net impact of florivory on plant reproduction could be strengthened or weakened if floral damage increases susceptibility to further damage, or induces defenses that reduce subsequent damage. The identity of the herbivore that first damages a plant can have cascading impacts on the entire community of subsequent consumers (e.g., Van Zandt and Agrawal 2004), and leaf herbivores can have strong indirect effects on plant reproduction by altering floral interactions. Early leaf damage by invasive Popillia japonica beetles to Oenethera biennis rosettes had little direct impact on reproduction but induced floral defenses that reduced seed predation, leading to a net increase in plant fitness (McArt et al 2013). While the effect of leaf damage on floral interactions is relatively well- studied, the effect of floral damage on leaf interactions remains unknown
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
