College of Life Sciences, Northwest Normal University, Lanzhou, 730070, Gansu, China.
College of Life Sciences, Central China Normal University, Wuhan, 430079, Hubei, China.
J Plant Res. 2024 Jul;137(4):605-617. doi: 10.1007/s10265-024-01536-1. Epub 2024 Mar 20.
The intervention of nectar robbers in plant pollination systems will cause some pollinators to modify their foraging behavior to act as secondary robbers, consequently adopting a mixed foraging strategy. The influence of nectar robbing on pollinator behavior may be affected by spatio-temporal difference of robbing intensity, and consequently, may have different effects on the pollination of host plants. However, whether and how the nectar robbing might influence pollinators under different robbing intensity still needs further investigation. In this study, Symphytum officinale was used to detect the effect of nectar robbers on pollinators under different robbing intensity as well as their effects on plant reproductive success. Six robbing levels and three bumblebees with mixed foraging behaviors were used to evaluate the effect of different robbing intensity on pollinator behavior, visitation rate, flower longevity and pollen deposition. Our results indicated that the robbing rate increased gradually with the proportion of robbed flowers, but which did not affect the frequency of legitimate visits. The increase of robbing rate promoted the corolla abscission, and then enhanced the self-pollen deposition, but which had no significant effect on cross-pollen deposition. These results indicate that the overall fitness of S. officinale was improved by combined self and cross-pollination modes when visited by both pollinators and nectar robbers simultaneously. Although nectar robbing is not uncommon, its consequences for pollination in the interaction web have not been well studied. Our results emphasize the significance of indirect impacts in mediating the adaptive outcomes of species interactions.
蜜掠夺者对植物传粉系统的干预会导致一些传粉者改变觅食行为，转而成为次要掠夺者，从而采取混合觅食策略。蜜掠夺对传粉者行为的影响可能受到掠夺强度的时空差异的影响，因此，可能对宿主植物的传粉产生不同的影响。然而，蜜掠夺是否以及如何在不同的掠夺强度下影响传粉者，仍需要进一步研究。在这项研究中，我们使用紫菀属植物来检测不同掠夺强度下蜜掠夺者对传粉者的影响，以及它们对植物生殖成功的影响。我们使用了 6 种掠夺水平和 3 种具有混合觅食行为的熊蜂，以评估不同掠夺强度对传粉者行为、访问率、花寿命和花粉沉积的影响。我们的结果表明，掠夺率随着被掠夺花朵的比例逐渐增加，但这并不影响合法访问的频率。掠夺率的增加促进了花瓣脱落，进而增强了自花粉沉积，但对异花粉沉积没有显著影响。这些结果表明，当同时受到传粉者和蜜掠夺者的访问时，紫菀属植物通过同时进行自交和异交的方式提高了整体适合度。尽管蜜掠夺并不罕见，但它对传粉在相互作用网络中的后果尚未得到很好的研究。我们的结果强调了间接影响在调节物种相互作用的适应结果方面的重要性。
