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Composition of tomatoes and tomato products in antioxidants (WG1) page 52
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Wilkens et al.(1996) investigated the influence of light resources on the accumulation
of the soluble phenolics rutin and chlorogenic acid by Cherry tomato plants in greenhouse,
together with the influence on growth. Plants grown under high light had approximately a
two-fold higher concentration of soluble phenolics than low-light plants.
6.4.3. Influence of cultural techniques
6.4.3.1. Variety
Senter et al.(1988) have shown that in tomato fruit the quantities of total phenols in the
epidermial tissue, the placental tissue, the radial and inner wall of the pericarp and the outer
wall of the pericarp (presented in § 6.4.1.) did not vary significantly among three tested
cultivars (Patriot, Floridade, Walter).
6.4.3.2. Mineral nutrition
Effect of Nitrogen
The pigment absorption spectrum of leaf ethanol extracts was analysed on tomato
seedlings (cv. UC82) which were cultivated until fruit-setting by Dumas et al.(1993) in sand
pots in glasshouse to study the influence of N availability (0, 2, 6 and 18 meq N L -1 nutrient
solution) in the root environment on growth and development. Leaf polyphenol content giving
a yellowish colour (absorbency measured between 300 and 350 nm) was considerably
increased by low N availability (2 meq compared to 6 and 18), which also resulted in a slower
rate of appearance of new trusses.
Wilkens et al.(1996) investigated the influence of nitrogen resources on the
accumulation of the soluble phenolics rutin and chlorogenic acid by Cherry tomato plants in
greenhouse, together with the influence on growth. Plants grown with low N resources
showed low levels of soluble phenolics and low plant mass. Plants grown with intermediate
levels of N resources showed high phenolic concentrations but inhibited growth. Plants grown
with high N resources had high growth but no increases in phenolic concentrations. The
phenolic concentrations were higher in younger leaves. The differences in phenolic