Over-expression of the CHIL gene in the chil and Col background. (A) Relative transcript levels of the CHIL gene in the Col wild-type, chil-1, three CHIL OE/chil-1 lines, and three CHIL OE lines detected by qRT-PCR analysis. (B) Seed phenotypes of Col, chil-1, CHIL OE-1/chil-1, and CHIL OE-1 after staining with DMACA for 20 d. Bars=0.2mm. (C) Relative level of proanthocyanidins in mature seeds of Col, chil-1, three CHIL OE/chil-1 lines, and three CHIL OE lines. The extractable PAs measured by DMACA (2.64mg epicatechin equivalence g–1) and by butanol (1.08mg B2 equivalence g–1); non-extractable PAs (2.50mg B2 equivalence g–1) in Col were set as a value of 1.0, respectively. (D, E) Relative levels of flavonols [quercetin (Q) and kaempferol (K) aglycones] in 21-d-old seedlings (D) and mature seeds (E) of Col, chil-1, three CHIL OE/chil-1 lines, and three CHIL OE lines. Levels of quercetin (4.79 µg g–1 dry weight and 584.27 µg g–1 dry weight in seedlings and seeds, respectively) and kaempferol (4.90 µg g dry weight and 11.38 µg g–1 dry weight in seedlings and seeds, respectively) from wild-type control Col were set as a value of 1.0. (A, C, D, E) Data are presented as mean ±SD, Student’s t test (n=3, *P <0.05, **P <0.01). (This figure is available in colour at JXB online.)