Soil moisture incidentally selects for microbes that facilitate locally adaptive plant response

We examined the role of the plant vs the environment in selecting for beneficial microbes to plants in their home moisture environment, in either wet vs dry conditions. To this end, we first conditioned soil microbial communities, selecting for either dry- or wet-adapted soil microbial communities, either with or without plants. After 3 plant generations, we conducted a full reciprocal transplant of each soil community onto wet- and dry-treated plants, using the soil from the prior 3 generations as an inoculum. From plants inoculated with these ‘evolved’ soils, we measured plant biomass and height. We also measured soil nitrogen of the inoculum, and measured inoculum respiration across a water content gradient.本研究旨在探究植物与环境在植物原生水分环境中对植物有益微生物的筛选效应，实验设置湿润与干旱两种水分条件。为此，我们首先对土壤微生物群落进行驯化处理，分别在有植物或无植物的条件下，筛选出适应干旱或湿润环境的土壤微生物群落。经过3个植物世代的培养后，我们以经前3代驯化的土壤作为接种剂（inoculum），开展完整的互易移栽实验：将每一组土壤微生物群落分别接种到湿润和干旱处理的植株中。从接种这些“驯化后”土壤的植株中，我们测定了植株的生物量与株高。此外，我们还测定了该接种剂的土壤氮含量，并在不同水分含量梯度下测定了接种剂的呼吸速率。