Fig. S3.

Gene expression response in lbo-1. Whole seedlings of lbo mutant and lbo max4 double mutant showed equal sensitivity in (A and B) the decrease of IAA5 and (C and D) the decrease of STH7 gene expression after 4 h treatment with different doses of 5-deoxystrigol (5DS) or 4DO. This result strongly suggests that lbo is not deficient in response to strigolactones, inferring that lbo may instead be defective in producing strigolactones. (A and B) IAA5 can be promoted by auxin (53) or repressed by strigolactones (54), and (C and D) SALT TOLERANCE HOMOLOG7 (STH7) can be promoted by karrikins or strigolactones (55). Mean ± SEM (n = 3; 10–15 seedlings each).