There are a wide variety of microbial inoculant types available to
restoration practitioners, but little information as to which performs
best under field conditions in dryland ecosystems. We used a
meta-analysis of 62 dryland studies to provide the first quantitative
comparison of native vs commercial, diverse vs single species, and
fungal vs bacterial microbial inoculants. We found that while microbial
inoculation increases plant growth compared to uninoculated
counterparts, contrary to our expectations, the magnitude of effect was
statistically similar for all the inoculant pairs. Our results suggest
that land managers should use inoculant types that are readily available
and easy to handle rather than complicated and expensive inoculants that
combine multiple taxa of local origin microbes.