Figure 9.

Levels of (A) the xanthophyll cycle pool constituents, violaxanthin, antheraxanthin, and zeaxanthin (V + A + Z), (B) lutein, (C) β-carotene, and (D) α-tocopherol per chlorophyll (Chl) a + b, (E) chlorophyll a + b levels per frond/leaf area, and (F) the molar ratio of chlorophylls a to b in fronds of Lemna minor (orange) and leaves of Malva neglecta (green) growing naturally in Superior, Colorado, USA. Mean values ± standard deviations; n = 4. Significant differences are denoted by asterisks; ** = p < 0.01, *** = p < 0.001.