The highest rate of synthesis and accumulation of lycopene in chromoplasts was detected in the transitional phase between the white-pink and the pink stage. This may possibly be due to a progressive activation of the molecular mechanisms involved in carotenogenesis regulation during the transition between the white and pink ripening stages, followed by a feedback inhibition of the pathway by end-products towards the end of fruit ripening.These mechanisms may include regulation at the transcriptional and/or post-transcriptional level, metabolite flux into the carotenoid pathway and carotenoid sequestration, as has been found in tomatoes (Bramley, 2002). In Crimson sweet cultivar, most of lycopene (78%) present in the red-ripe fruit had already been synthesized and stored by the pink stage, whereas only a lower percentage, ranging from 31% to 53%, had already been synthesized and stored in P503, Dumara, P403 and Giza cultivars.