Figure 1.

The B. distachyon ortholog of RAM1 is expressed in roots colonized by AM fungi. A, BdRAM1 gene expression is induced in roots colonized by the AM fungus D. epigaea (gray bars) relative to nonmycorrhizal, mock-inoculated roots (white bars). Plants were harvested 4, 6, and 8 weeks postplanting (wpp). AM-induced BdRAM1 gene expression increases over time. B, Gene expression of the AM marker genes BdPT7 and D. epigaea (D.e.) α-tubulin in D. epigaea-colonized and mock-inoculated control roots over time. A and B, Gene expression was measured by reverse transcription quantitative PCR (RT-qPCR) and normalized to the B. distachyon elongation factor BdEF1α. Bar graphs show the mean, with error bars representing sd. Single points represent individual measurements. Pairwise comparisons of gene expression in AM and control roots were analyzed separately for each time point using Student’s t test (***P < 0.001, **P < 0.01, and *P < 0.05).