The loss of long‐tongued pollinator species and dominance of a few short‐tongued generalist species, related to agricultural intensification in recent decades, may have consequences for the quality, quantity, and stability of yields in insect‐pollinated crops. Interestingly, the changes in pollinator community coincide with an increase in poor and variable seed yield in red clover, an important crop for green manure and forage production. However, to date we lack a holistic understanding of the factors that drive seed yield in red clover crops. To remedy this, we related plant and pollinator traits to pollinator visitation, behavior, and pollination efficiency in four diploid and five tetraploid red clover cultivars during three years in a common garden setting. Tetraploid cultivars produced 52% fewer seeds and 41% lower seed weight per flower head compared with diploid cultivars. They also had fewer flower heads per plant, larger florets, and lower pollen viability than diploids. Pollinator species with shorter tongues visited diploid cultivars more frequently than tetraploid cultivars. Pollinator species with longer tongues deposited more pollen and showed higher pollination efficiency in terms of seeds produced after single visits. Our results suggest that while both diploid and tetraploid red clover cultivars benefit from the presence of longer‐tongued pollinator species, seed yield in tetraploid cultivars may be more sensitive to the loss of these bumble bee species in intensively cultivated agricultural landscapes.

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植物的倍性和传粉者的舌长是否相互作用，导致红三叶草的种子产量低？

近几十年来，与农业集约化有关的长期授粉的传粉者物种的丧失和少数短期对话的通才物种的优势可能对昆虫授粉作物的产量，质量和稳定性产生影响。有趣的是，授粉媒介群落的变化与红三叶草（绿肥和草料生产的重要作物）的差而可变的种子产量增加同时发生。但是，迄今为止，我们对驱动红三叶草作物种子产量的因素缺乏全面的了解。为了解决这个问题，我们将植物和授粉媒介的性状与普通花园环境中的四个二倍体和五个四倍体红三叶草品种的授粉媒介访视，行为和授粉效率相关联。与二倍体栽培品种相比，四倍体栽培品种每头状花序产生的种子减少52％，种子重量减少41％。与二倍体相比，它们的单株花序更少，花序更大，花粉活力更低。舌头较短的授粉物种比四倍体品种更频繁地拜访二倍体品种。较长舌头的传粉媒介种类沉积了更多的花粉，单次造访后产生的种子显示出更高的授粉效率。我们的研究结果表明，虽然二倍体和四倍体红三叶草品种都受益于更长的传粉媒介，但在集约耕作的农业景观中，四倍体品种的种子产量可能对这些大黄蜂物种的丧失更为敏感。小花比二倍体大，花粉活力低。舌头较短的授粉物种比四倍体品种更频繁地拜访二倍体品种。较长舌头的传粉媒介种类沉积了更多的花粉，单次造访后产生的种子显示出更高的授粉效率。我们的研究结果表明，虽然二倍体和四倍体红三叶草品种都受益于更长的传粉媒介，但在集约耕作的农业景观中，四倍体品种的种子产量可能对这些大黄蜂物种的丧失更为敏感。小花比二倍体大，花粉活力低。舌头较短的授粉物种比四倍体品种更频繁地拜访二倍体品种。较长舌头的传粉媒介种类沉积了更多的花粉，单次造访后产生的种子显示出更高的授粉效率。我们的研究结果表明，虽然二倍体和四倍体红三叶草品种都受益于更长的传粉媒介，但在集约耕作的农业景观中，四倍体品种的种子产量可能对这些大黄蜂物种的丧失更为敏感。较长舌头的传粉媒介种类沉积了更多的花粉，单次造访后产生的种子显示出更高的授粉效率。我们的研究结果表明，虽然二倍体和四倍体红三叶草品种都受益于更长的传粉媒介，但在集约耕作的农业景观中，四倍体品种的种子产量可能对这些大黄蜂物种的丧失更为敏感。较长舌头的传粉媒介种类沉积了更多的花粉，单次造访后产生的种子显示出更高的授粉效率。我们的研究结果表明，虽然二倍体和四倍体红三叶草品种都受益于更长的传粉媒介，但在集约耕作的农业景观中，四倍体品种的种子产量可能对这些大黄蜂物种的丧失更为敏感。