PMC

Late successional native prairie plant species (black symbols) had higher mycorrhizal responsiveness and higher coefficient of variation in mycorrhizal responsiveness than early successional native plant species (gray symbols) and nonnative plant species (white symbols). Coefficient in variation of mycorrhizal responsiveness, a measure of plant sensitivity to different arbuscular mycorrhizal (AM) fungal isolates, was highly correlated with mycorrhizal responsiveness (R ² = 0.66, P < 0.0001).

Plant successional stage was a strong predictor of (a) plant growth response to arbuscular mycorrhizal fungi (i.e., mycorrhizal responsiveness) and (b) coefficient of variation in responsiveness among different fungal isolates. Bars and error bars represent plant successional stage means ± SE; symbols represent individual nonnative plant species (white symbols), early successional native prairie plant species (gray symbols), and late successional native prairie plant species (black symbols).

Across studies, late successional native plants (dark gray panel, right) had a greater change in biomass when grown with arbuscular mycorrhizal (AM) fungi than nonnative plant species (white panel, left) or early successional native plant species (light gray panel, middle) relative to uninoculated controls. Studies shown in this figure include (a) Klironomos (; data from Fig. 1); (b) Koziol and Bever (; data from Fig. 1); and greenhouse experiments presented herein, (c) Experiment 1 and (d) Experiment 2. Different colored bars in each graph represent the percentage change in biomass of plants inoculated with individual AM fungal isolates or mixtures of AM fungal isolates relative to uninoculated controls. This figure shows that nonnative and early successional native grassland plant species have no or low response to AM fungi while the late successional native grassland plant species across studies are highly responsive to AM fungi and are sensitive to different AM fungal isolates. AM fungal species are (a) Acaulospora denticulata (light red), Acaulospora morrowiae (light blue), Gigaspora margarita (light purple), Gigaspora rosea (light green), Rhizophagus intraradices (dark green), Claroideoglomus etunicatum (dark gray), Funnelformis geosporum (light gray), Funnelformis mosseae (Canadian isolate, light orange), Cetraspora pellucida (brown), and Scutellospora calospora (yellow); (b–d) Acaulospora spinosa (blue), Entrophospora infrequens (red), Claroideoglomus lamellosum (green), Claroideoglomus claroideum (purple), Funnelformis mosseae (Illinois, USA isolate, gray), F. mosseae (Indiana, USA isolate; turquoise), Racocetra fulgida (orange), Cetraspora pellucida (brown), and AM fungal species mixtures (black). All plant‐fungal combinations were co‐occurring in their respective studies.