Cell-specific localization of proanthocyanidins in white clover floral organs. Corolla of a white clover flower (A). Transverse sections through petals at different stages of development after DMACA staining and embedding in LR White resin (B-C). Longitudinal section through an immature white clover flower (D). Longitudinal section through an immature white clover flower (E). Longitudinal section through a trichome (F). All tissues were stained with DMACA and embedded in LR White resin. ab-abaxial surface of organ; ad-adaxial surface of organ; ca-carpel; kp-keel petals; ov-ovule; se-sepals; sf-stamen filament; sp-standard petal; wp-wing petal; tr-trichomes; va-vacuole. Bars represent 1 mm (A), 50 μm (B-E) and 5 μm (F).