| Abstract
| - Carotenoids and tocopherols are powerful antioxidants synthesized in plants from a common precursor.They may offer significant health benefits to humans. Seed oils have been shown to possess highlevels of tocopherols, but little is known about their levels in the edible portions of most vegetablecrops. A two-year field experiment was conducted at two locations to assess levels of majorcarotenoids and tocopherols in carrot (Daucus carota) root and leaf tissue. Levels of compounds inroot tissue reported on a dry weight basis were as follows: α-tocopherol, 0.04−0.18 ppm; lycopene,0.00−52.94 ppm; α-carotene, 10.63−1504.76 ppm; and β-carotene, 26.69−1673.76 ppm. Higherlevels of all carotenoids were measured in phloem tissue than in xylem. Leaf tissue levels oftocopherols measured on a dry weight basis ranged from 0.02 to 0.85 ppm, whereas levels ofcarotenoids ranged from 12.81 to 411.66 ppm. In xylem tissue, α-tocopherol was significantly (P ≤0.001) positively correlated with α-carotene (r = 0.65) and with β-carotene (r = 0.52). This positivecorrelation indicates it may be possible to select for both increased α-tocopherol and carotenoids incarrot. The reduced pigment (rp) mutation of carrot exhibited a 96% reduction in levels of α- andβ-carotene and a 25−43% reduction in α-tocopherol when compared to a near-isogenic line. In plantshomozygous for rp, a substantial increase was observed in phytoene, a precursor to carotenoids,suggesting the location of the rp lesion in the carotenoid synthesis pathway. Keywords: Carrot; Daucus carota; HPLC; vitamin A; vitamin E; lycopene; α-carotene; β-carotene;α-tocopherol
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