Fig. 4

The relative bisbibenzyls content and the expression level of PabHLH1 in P. appendiculatum. a Three different tissues of P. appendiculatum, 1, 2: axenic callus and thallus cultured on MS medium; 3: thallus growing in greenhouse. b Relative bisbibenzyls content in three tissues referred to in (a). c PabHLH1 transcript abundance by qRT-PCR in the three tissue types referred to in (a). Data represent mean ± S.D. with three biological repeats. *p < 0.05, ** p < 0.01 according to Student’s t-test