Effect of expanded variation in anther position on pollinator visitation to wild radish, Raphanus raphanistrum

Background and Aims: Plant-pollinator interactions shape the evolution of flowers. Floral attraction and reward traits have often been shown to affect pollinator behavior, but the possible effect of efficiency traits on visitation behavior has rarely been addressed. Here we tested for the effect of anther position, usually considered a trait that influences efficiency of pollen deposition on pollinators, on pollinator visitation rates and visit duration in flowers of wild radish, Raphanus raphanistrum. Methods: We used artificial selection lines from two experiments that expanded the naturally-occurring phenotypic variation in anther position. In one experiment, plant lines were selected to either increase or decrease anther exsertion. The other experiment decreased anther dimorphism, which resulted in increased short stamen exsertion. We hypothesized that increased exsertion will increase visitation of pollen foragers due to increased visual attraction. We also hypothesized that exsert...背景与研究目的：植物-传粉者互作塑造了花的演化。花的吸引性状与报酬性状常被证实会影响传粉者行为，但效率相关性状对访花行为的潜在影响却极少得到关注。本研究以野萝卜（Raphanus raphanistrum）的花朵为研究对象，测试了通常被认为会影响花粉在传粉者身上沉积效率的花药位置性状，对传粉者访花频率及停留时长的影响。 研究方法：我们依托两项扩增了花药位置自然表型变异的人工选择实验所构建的品系开展研究。其中一项实验中，我们通过人工选择培育出花药伸出量增加或减少的植物品系；另一项实验则降低了花药二态性，最终导致短雄蕊的伸出量增加。我们提出假设：花药伸出量增加会通过提升视觉吸引力，提升花粉采集者的访花频次。我们同时假设，花药伸出