Biosynthesis of L-ascorbic acid in animals and plants has been discussed and compared. The production sites of this vitamin have been presented. L-ascorbic acid is not detectable in plant seed and is synthesized during germination which is influenced by environmental temperature. The species that are unable to synthesize L-ascorbic acid lack the microsomal enzyme, L-gulono-oxidase, which converts L-gulonolactone to 2-keto-L-gulonolactone. This is considered to be a genetic defect. The pathway of L-ascorbic acid biosynthesis in animals is more clear than that in plants. Radiation induced synthesis of ascorbic acid in germinating mungbeans, was studied. A dose of 0.1 kGy resulted in the development of maximum amount (35.5 mg/100g) as compared with 29.7 mg/100g in the unirradiated controls after 48 hours of germination.