Effect of gamma-Irradiation on the Biosynthesis of Carotenoids in the Tomato Fruit.

Fruits of the lutescent tomato genetic line were exposed to gamma-radiation at different stages of maturity to determine the effect of ionizing radiation on carotenoid synthesis in the ripening fruit. Irradiation generally resulted in the inhibition of carotenogenesis. The effect was more pronounced at the higher dosage and in less mature fruit. Lycopene synthesis was inhibited more extensively than beta-carotene synthesis. The total carotenoid content was also generally lower in irradiated fruits. It was proposed that the beta-carotene in the tomato fruit is formed by a pathway not involving lycopene.