The fate of a plant defense mutualism in a warming world at the University of Michigan Biological Station, Pellston, MI (2024-2026)

Mutualisms are vital to plant survival and reproduction, but climate warming has the potential to alter these interactions. One such mutualism involves foliar mites, which provide plants with defense by consuming harmful fungi. In exchange, plants offer protective structures on their leaves called domatia. Both mite and fungal communities are potentially temperature-sensitive, and warming may shift community composition, potentially altering trophic interactions between botch groups. However, the specific changes in mite and fungal community composition and their implications for plant-mite mutualism and plant performance remain unclear. To investigate the responses of both of these communities to warming, and the effects these changes will have on plants, I conducted a nested factorial field experiment with 96 P. serotina seedlings at the University of Michigan Biological Station. Plants were warmed using open top chambers, nested within which were fully factorial manipulations of the mite and fungal communities. Each group was manipulated using either pruning tar to exclude mites or Quilt fungicide to exclude fungi.

互利共生关系对植物的存活与繁殖至关重要，但气候变暖有可能改变这类物种间的相互作用。其中一类互利共生涉及叶面螨（foliar mites）：它们通过取食有害真菌为植物提供防御，作为交换，植物会在叶片上形成名为螨类庇护叶穴（domatia）的保护性结构。螨类与真菌群落均具有温度敏感性，气候变暖可能改变其群落组成，进而可能改变两类群之间的营养相互作用。然而，螨类与真菌群落组成的具体变化，以及这些变化对植物-螨类互利共生关系与植物生长表现的潜在影响，目前仍不明确。为探究这两类群落对气候变暖的响应，以及这些变化对植物的影响，本研究在密歇根大学生物站开展了一项嵌套析因野外实验，共使用96株P. serotina实生苗。研究采用开顶式气室（open top chambers）对植物进行增温处理，气室内嵌套设置了螨类与真菌群落的全因子操控实验。每个操控组分别通过两种方式进行处理：使用修剪焦油（pruning tar）排除螨类，或使用Quilt杀菌剂（Quilt fungicide）抑制真菌。