Effect of light quality (LQ) and lighting method (LM) on canopy area on day 21 (CA21), total leaf area (LA), biomass per unit area (BMA), and shoot dry weight (SDW) in red romaine lettuce.

Least-square means with standard error of the model (in parenthesis) are shown in the table. Statistical significance of the main and interaction effects of the fitted model is shown below the table. The symbol ‘*’ and ‘n.s.’ indicate P values ≤ 0.05 and no statistical significance, respectively. In addition, P values close to statistical significance are shown. The least-square means with a different letter are statistically different (Tukey-Kramer procedure).