Novel nectar robbing negatively affects reproduction in Digitalis purpurea

Abstract

Many plant-pollinator interactions are undergoing change due to multiple anthropogenic influences (González-Varo et al., 2013;Goulson et al., 2015). At present, we have a limited understanding of how novel interactions affect plant reproductive success, for example, after plant invasion (Barrett et al., 2008;Chalcoff et al., 2019;Richardson et al., 2000). One interaction with consequences for plants is nectar robbing, where plants have their mutualism with pollinators bypassed by floral visitors (robbers) that consume nectar rewards without pollinating (Irwin et al., 2010). In the same way as pollination mutualisms, this interaction between

Nectar robbing by bees affects the reproductive fitness of the distylous plant Tirpitzia sinensis (Linaceae)

“…Nectar robbing can directly damage floral reproductive structures (Traveset et al., 1998), decrease nectar volume (Hazlehurst & Karubian, 2016), influence female and/or male fitness, and reduce fruit and seed sets (Irwin & Brody, 1999). Indirectly, robbing may reduce the number of pollen grains deposited per visit, visit rates, or visit duration of the legitimate pollinator (Irwin et al., 2015; Mackin et al., 2021; Varma et al., 2020) and thus affect reproductive success. Neutral consequences have been inferred when nectar robbing had no significant effects on plant reproductive success because pollinator behavior was not modified by nectar robbing (Elena & Jaime, 2019; Rojas‐Nossa et al., 2016a; Souza et al., 2019; Ye et al., 2017).…”