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Composition of tomatoes and tomato products in antioxidants (WG1) page 36
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Ethephon ((2-chloroethyl)phosphonic acid) is a plant growth and development
regulator (flower induction, dwarfing effect) with systemic properties, progressively
decomposed to ethylene in plant tissues. It is also known to enhance the ripening of green
tomatoes by accelerating colour development.
Gibberellins are plant growth promoters through stimulation of stem elongation,
promotion of seed germination, inducement of flowering and fruit formation, changes of plant
metabolism.
CCC or Cycocel (2-chloroethyl trimethylammonium 3-chloride), Phosphon (2,4-
dichlorobenzyl tributyl phosphonium chloride) and Alar (succinic acid 2,2-dimethyl
hydrazide) are growth retardants generally inducing dwarfing effects.
Duraset (N-metatolyl phtalamic acid) and the cytokinin Adenin (6-aminopurine) are
growth substances exhibiting auxin.
Rabinowich and Rudish (1972) dipped full sized green tomato fruits cv. Moneymaker
during one minute into CPTA and/or ethephon solutions at various concentrations (0 to 4800
mg/l) and observed colour development at room temperature or at 32°C. At room
temperature, ethephon treatments enhanced fruit ripening and combining ethephon with
CPTA resulted in faster and higher lycopene accumulation. At 32°C, only both CPTA and the
combined ethephon and CPTA treatment resulted in an accumulation of red colour. CPTA
appeared to prevent from the inhibition of lycopene synthesis by high temperature. The
hypothesis of a pathway of lycopene synthesis different from the natural pathway in these
conditions was proposed.
Detached fruit at the breaker stage of normal red and high-beta tomato genotypes were
dipped by Chang et al.(1977) for 1 min in an aqueous solution containing CPTA (4300
µg/mL) and 1% Tween 80 as a surfactant, then were allowed to ripen at 21 or 32°C for 6 or
12 days. Treatment of normal red fruit generally resulted in an increased synthesis of
phytoene, phytofluene, ξ-carotene, lycopene (up to 550-580 mg/kg dry matter) and of γ-
carotene with a concomitant decrease of the synthesis of β-carotene when ripened for 6 and
12 days at 21°C. At 32°C, lycopene synthesis was much lower (up to 100 and 230 mg/kg dry
matter for 6 and 12 days respectively) and not stimulated by CPTA treatment. The high-beta
fruit produced relatively large amounts of β-carotene (about 1700 and 700 mg/kg dry matter
at 21 and 32°C respectively) and small amounts of lycopene (1 and 120 mg/kg dry matter at
21°C/6 and 12 days respectively). CPTA reduced high-beta fruit β-carotene content of 31 to