Fig. 10. Relationship between canopy photosynthetic rate (Pn) and either chlorophyll concentration (A) or anthocyanin level (B), or chlorophyll/anthocyanin ratio (C). Each symbol represents mean values of four replications within treatment, date, and year. Dates were after 100 d after planting, when canopy photosynthetic rates were declining and their nearest date of corresponding pigment measurement.