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Composition of tomatoes and tomato products in antioxidants (WG1) page 27
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On the contrary, in red and pink cherry tomato cultivars, Matsuzoe et al.(1998) found
that total carotene of fully ripe fruits and the amount of lycopene were increased by soil water
deficit. In red and pink large-fruited tomatoes, soil water deficit also tended to increase the
amount of lycopene per fresh matter in the outer pericarp region but it had no effect on the
amount and distribution of β-carotene and xanthophylls (Zushi and Matsuzoe, 1998).
6.1.4.3. Mineral nutrition
Effect of Nitrogen
Aziz (1968) has cultivated tomato cv. Moneymaker in nutrient solution at three levels
of nitrate nitrogen (1.0, 12.9 -considered as normal level- and 15.8 milli-equivalents). Fruit
under the low N level were earlier and higher in gaining both total carotene and lycopene than
those under the normal or the high N levels (1.0, 12.9 and 15.8 m.e. yielded 68, 44 and 38
mg/kg fresh matter fruit of lycopene content respectively). On the contrary yield increased
with N level. It was concluded that for good colour in tomato fruit, N supply should be as low
as possible without reducing fruit yield.
Montagu et al.(1990) cultivated tomatoes in pots filled with peaty loam soil. Various
forms (nitrate, ammonium, compost, blood and bone) of nitrogen were applied at four rates
(0, 150, 300, 600 kg N/ha). Fruit lycopene content tended to increase in average of 30% when
N applied increased, except with compost.
More generally, nitrogen fertilizers have been presented as able to increase the
concentrations of carotenes in plants (Mozafar, 1993), but few specific information seems to
be available.
Effect of Phosphorus
Saito and Kano (1970) found that increased P supply (from 0 to 100 mg/l of nutrient
solution) in hydroponic culture greatly improved the fruit colour and lycopene content. Few
specific information seems to be available.
Effect of Potassium
For tomato plants (var. Fireball) grown in sand culture in a growth chamber (16-h light
period at 24°C and 8-h dark period at 18°C, 65% relative humidity) and at any particular stage