Evaluating Performance of Bouteloua gracilis Cultivars After Drought: The Role of the Soil Microbiome

ABSTRACT After the Dust Bowl in the 1930s, it was common to reseed native grasses in areas impacted by the drought to help restore grassland ecosystem structure and function. Given the forecasts of intensified drought events, reseeding may need to be employed more frequently to enhance post‐drought recovery. For such reseeding efforts, it is imperative to understand the adaptability of cultivars to the environmental conditions in which they are planted, including how they interact with the soil microbiome. Here, we used a greenhouse experiment with two cultivars of the C 4 grass, Bouteloua gracilis , that were planted with soil microbial inocula extracted from either previously droughted or non‐droughted soils collected from native shortgrass prairie in northeastern Colorado (USA). Our goal was to examine whether the post‐drought legacy of altered soil microbial communities affected the growth and performance of two B. gracilis cultivars. We found no significant differences in relative growth rate or plant biomass, and minimal differences in the microbial community composition between the two cultivars, despite differences in microbial communities at the beginning of the experiment. These results suggest that the post‐drought legacy of altered soil microbial communities does not differentially affect growth and performance of the two B. gracilis cultivars evaluated, and that these cultivars do not differ in their effects on the soil bacterial communities found under ambient versus previously droughted conditions.