Fig. 6

Overview of putative carotenoid biosynthesis pathways involved in rice and expression profiles of genes involved in this pathway. A The schematic of carotenoid biosynthesis pathway was shown in brief. B Carotenoid contents in Yu17S and MH63 under cold stress (2–48 h) and recovery for 24 h after 48 h treatment. C-H Relative expression of genes involved in carotenoid biosynthesis pathway. Error bars indicate the SD for three independent replicates. * and ** indicate a significant difference between MH63 and Yu17S at P < 0.05 and P < 0.01 levels, respectively (two tailed T-test). Different letters indicate significant differences among treatments (P < 0.05, ANOVA). FW, fresh weight; PSY, phytoene synthase; PDS, phytoene desaturase; Z-ISO, 15-cis-ζ-carotene isomerase; CRTISO, carotene isomerase; LCY-e, lycopene ε-cyclase; BCH, β-carotene hydroxylase