Fig. 5.

Carotenoid levels and polished color of interbred seeds of rice from two independent lines of OsCCD1-RNAi, OsCCD4a-RNAi, and OsCCD4b-RNAi and a stPAC plant displaying carotenoid-accumulating golden colored seeds. (a) Carotenoid levels, measured by HPLC, of homozygous F₄ seeds containing two transgenes: stPAC and one of the RNAi genes, compared with non-transgenic (NT) plants (Oryza sativa cv. Ilmi). Data are means (±SD) of three replicates. The relative difference compared with each nullizygous (N) rice seed was determined using a one-tailed Student’s t-test. The nullizygous rice line has only a stPAC gene and is without the RNAi gene for each of the OsCCDs after being segregated from interbreeding lines (b) Fold-changes in individual carotenoid components of homozygous F₄ seeds relative to that of each N seed. Differences between groups relative to a value of 1 were also determined using a one-tailed Student’s t-test. All significant differences in (a, b) are indicated as ***P<0.001, * P<0.01, *P<0.05. (c) Phenotypes of endosperm colors in homozygous F₄ seeds after polishing. Line numbers with significantly enhanced carotenoid contents in (a, b) and a slightly more intense golden color compared with each N line are highlighted in bold.