Ye Zhong-Ming, Jin Xiao-Fang, Wang Qing-Feng, Yang Chun-Feng, Inouye David W
Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention, Jiangxi Institute of Soil and Water Conservation, Nanchang 330029, China.
Ann Bot. 2017 Apr 1;119(6):1053-1059. doi: 10.1093/aob/mcw285.
It has been suggested that the dynamics of nectar replenishment could differ for flowers after being nectar robbed or visited legitimately, but further experimental work is needed to investigate this hypothesis. This study aimed to assess the role of nectar replenishment in mediating the effects of nectar robbing on pollinator behaviour and plant reproduction.
Plant-robber-pollinator interactions in an alpine plant, Salvia przewalskii , were studied. It is pollinated by long-tongued Bombus religiosus and short-tongued B. friseanus , but robbed by B. friseanus . Nectar production rates for flowers after they were either robbed or legitimately visited were compared, and three levels of nectar robbing were created to detect the effects of nectar robbing on pollinator behaviour and plant reproduction.
Nectar replenishment did not differ between flowers that had been robbed or legitimately visited. Neither fruit set nor seed set was significantly affected by nectar robbing. In addition, nectar robbing did not significantly affect visitation rate, flowers visited within a plant per foraging bout, or flower handling time of the legitimate pollinators. However, a tendency for a decrease in relative abundance of the pollinator B. religiosus with an increase of nectar robbing was found.
Nectar robbing did not affect female reproductive success because nectar replenishment ensures that pollinators maintain their visiting activity to nectar-robbed flowers. Nectar replenishment might be a defence mechanism against nectar robbing to enhance reproductive fitness by maintaining attractiveness to pollinators. Further studies are needed to reveal the potential for interference competition among bumble bees foraging as robbers and legitimate visitors, and to investigate variation of nectar robbing in communities with different bumble bee species composition.
有人提出，花蜜被窃取或正常被访后，花朵的花蜜补充动态可能有所不同，但需要进一步的实验研究来验证这一假设。本研究旨在评估花蜜补充在调节花蜜窃取对传粉者行为和植物繁殖的影响中所起的作用。
对高山植物 przewalskii 鼠尾草的植物 - 窃取者 - 传粉者相互作用进行了研究。它由长舌的中华蜜蜂和短舌的弗里氏蜜蜂传粉，但会被弗里氏蜜蜂窃取花蜜。比较了花蜜被窃取或正常被访后花朵的花蜜分泌速率，并设置了三个花蜜窃取水平，以检测花蜜窃取对传粉者行为和植物繁殖的影响。
被窃取花蜜的花朵和正常被访的花朵在花蜜补充方面没有差异。坐果率和结籽率均未受到花蜜窃取的显著影响。此外，花蜜窃取对合法传粉者的访花率、每次觅食回合内一株植物上被访的花朵数量或花朵处理时间均无显著影响。然而，发现随着花蜜窃取增加，传粉者中华蜜蜂的相对丰度有下降趋势。
花蜜窃取并未影响雌性生殖成功，因为花蜜补充确保了传粉者对被窃取花蜜的花朵保持访花活动。花蜜补充可能是一种抵御花蜜窃取的防御机制，通过维持对传粉者的吸引力来提高繁殖适合度。需要进一步研究来揭示熊蜂作为窃取者和合法访花者觅食时干扰竞争的可能性，并调查不同熊蜂物种组成群落中花蜜窃取的变化情况。
