Fig. 1From: Selection of reference genes for the quantitative real-time PCR normalization of gene expression in Isatis indigotica fortuneCycle threshold value (Ct) of nine candidate reference genes across all samples. The box chart indicates the interquartile range. The outer box represents the 25th to 75th percentiles, and the inner box represents the mean values. The lower and upper dashes depict the minimum and maximum values. The line across the box is the median. The asterisks represent the outliersBack to article page