Data from: Trait responses to AM fungi are stronger and more consistent than fixed differences among populations of Asclepias speciosa

Premise of the study: Arbuscular mycorrhizal (AM) fungi can promote plant growth and reproduction, but other plant physiological traits or traits that provide defense against herbivores can also be affected by AM fungi. However, whether responses of different traits to AM fungi are correlated, and whether these relationships vary among plants from different populations is unresolved. Methods: We assessed whether different populations of the perennial forb, Asclepias speciosa, grown from seed collected from different environmental conditions across its distributional range respond differently to AM fungi, and if the responses of six growth and defense traits are correlated. Key Results: Although there was strong genetic differentiation in mean trait values among populations, AM fungi consistently increased expression of most growth and defense traits across all populations. Responses of biomass and root:shoot ratio to AM fungi were positively correlated, suggesting that plants that are more responsive to AM fungi allocated more biomass belowground. Responses of biomass and trichome density to AM fungi were negatively correlated, indicating a trade-off in responsiveness between a growth and defensive trait. Conclusions: Our results suggest that while there is substantial population differentiation in many traits of A. speciosa, populations respond similarly to AM fungi, and both positive and negative correlations among trait responses occur.研究背景：丛枝菌根（Arbuscular mycorrhizal, AM）真菌可促进植物的生长与繁殖，同时也会影响植物的其他生理性状或抗植食性防御性状。然而，不同性状对AM真菌的响应是否存在相关性，且这类相关性是否因不同种群的植物而异，目前仍未明确。 研究方法：本研究以多年生草本植物马利筋（Asclepias speciosa）为研究对象，其种子采自该物种分布范围内不同环境条件下的多个种群。我们评估了这些种群对AM真菌的响应是否存在差异，并分析了6个生长与防御性状的响应之间是否存在关联。 主要结果：尽管各种群的性状均值存在显著的遗传分化，但AM真菌在所有种群中均持续提升了多数生长与防御性状的表达水平。生物量与根冠比对AM真菌的响应呈正相关，表明对AM真菌响应更强的植物会将更多生物量分配至地下部分。生物量与表皮毛密度对AM真菌的响应呈负相关，说明生长性状与防御性状的响应之间存在权衡关系。 结论：本研究结果表明，尽管A. speciosa的诸多性状存在显著的种群分化，但不同种群对AM真菌的响应模式整体相似，且性状响应间同时存在正相关与负相关的关联。