Synthesis of β-Carotene in the Tomato Fruit

1. Two tomato crosses were examined. By use of the pigment mutant apricot (at at) which inhibits the production of lycopene in the fruit of the tomato but does not inhibit the "normal" production of β-carotene, it was shown that the action of the gene B in producing more than normal quantities of β-carotene is dependent upon a system which would otherwise produce lycopene in quantity. Support for this view is derived from a cross in which the quantity of lycopene was enhanced genetically, resulting in an appropriate increase in β-carotene in B-carrying strains. 2. These results support earlier investigations with regard to the action of B and enhance an earlier suggestion that, in the fruit of the tomato, β-carotene may be derived by two separate paths.