Pollen Sensitivity to Ultraviolet-B Suggests Floral Structure Evolution in Alpine Plants

摘要

The diversifi cation and evolution of fl oral traits are driven by both biotic and abiotic agents.The most well-studied agent is rain,which can wash away pollen grains,reduce pollen viability and dilute nectar thus affecting the reproductive fitness directly or indirectly.Strong ultraviolet radiation(especially UV-B radiation)is also known to reduce pollen viability,and strong UV-B radiation is a typical characteristic of alpine environments;accordingly,it may exert selection pressures on fl oral traits of alpine plants as well.However,the influence of UV-B radiation on the evolution of flower structure remains relatively unexplored.According to previous research,the reflexed flower stalk of Anisodus luridus during