Dawson-Glass Emma, Sanders Nathan J, Weber Marjorie G
Department of Ecology and Evolutionary Biology University of Michigan Ann Arbor Michigan USA.
Ecol Evol. 2025 Sep 18;15(9):e72151. doi: 10.1002/ece3.72151. eCollection 2025 Sep.
Many plants engage in indirect defense via tri-trophic interactions whereby plants provide resources such as food or shelter to mutualists in exchange for protection against herbivores and pathogens, increasing plant fitness. As temperature regimes shift under climate change, understanding the influence of temperature on tri-trophic defensive interactions is increasingly important. However, where plant species host multiple tri-trophic defensive interactions, we still lack an understanding of if each interaction, even within the same system, responds in the same way to temperature. In this study, we monitored black cherry ( seedlings for 10 weeks under ambient and increased temperatures to explore the effects of temperature on two different tri-trophic defensive interactions between black cherry and: (1) mutualistic leaf domatia-dwelling mites and leaf fungi; and (2) arthropod predators and herbivores. We found that the positive association between mite abundance and domatia size increased by 8.7% on warmed plants, while warming weakened the positive relationship between mite abundance and the abundance of foliar fungi by 14%, though warmer conditions alone did not affect the abundances of any of these groups. Further, warming increased the abundance of arthropod predators by 116% and decreased the amount of herbivory plants experienced by 42%, but did not modify the impact predators had on herbivory. Ultimately, the differences among interacting species with warming did not translate to differences in plant growth, indicating black cherry can be robust to at least some of the variation in species interactions caused by changing temperatures in the short term. These findings illustrate that warming can modify the abundance of, and relationships between, some but not all tri-trophic defensive interactions in a given system, further confirming that temperature does not impact plant interactions uniformly.
许多植物通过三级营养相互作用进行间接防御，即植物为互利共生者提供食物或庇护所等资源，以换取免受食草动物和病原体侵害的保护，从而提高植物的适合度。随着气候变化导致温度格局发生变化，了解温度对三级营养防御相互作用的影响变得越来越重要。然而，当植物物种存在多种三级营养防御相互作用时，我们仍然不清楚每种相互作用，即使在同一系统内，对温度的响应是否相同。在本研究中，我们在环境温度和升高温度条件下对黑樱桃幼苗进行了为期10周的监测，以探究温度对黑樱桃与以下两种不同三级营养防御相互作用的影响：（1）互利共生的叶窝螨和叶真菌；（2）节肢动物捕食者和食草动物。我们发现，在温度升高的植株上，螨类丰度与叶窝大小之间的正相关增加了8.7%，而升温使螨类丰度与叶面真菌丰度之间的正相关减弱了14%，不过仅温度升高的条件并未影响这些类群中任何一个的丰度。此外，升温使节肢动物捕食者的丰度增加了116%，使植物遭受的食草动物啃食量减少了42%，但并未改变捕食者对食草动物啃食的影响。最终，随着温度升高，相互作用物种之间的差异并未转化为植物生长的差异，这表明黑樱桃在短期内至少能对温度变化引起的物种相互作用的某些变化具有较强的适应性。这些发现表明，升温可改变给定系统中部分而非全部三级营养防御相互作用的丰度及相互关系，进一步证实温度对植物相互作用的影响并非均匀一致。
