S Senthilkumar, and RM Vijayakumar.
Plant pigments are essential for the attractiveness of fruits, accumulating most often in the skin during ripening process. The most important pigments of fruit include carotenoids and anthocyanins. Beside their role in pigmentation, they are important for human health as a source of vitamin A and antioxidant compounds. Carotenoids comprise carotenes, derived from terpenoids are synthesized in fruit at a high rate during the transition from chloroplast to chromoplast. Anthocyanins, a class of flavonoids derived ultimately from phenylalanine, are water-soluble, synthesized in the cytosol, and localized in vacuoles. They provide a wide range of colors ranging from orange/red to violet/blue. They are widely distributed in the plant kingdom. Betalains, nitrogen-containing water-soluble compounds derived from tyrosine, also conferring yellow-to-red colors, found only in a limited number of plant lineages. All three classes of pigments act as visible signals to attract insects, birds and animals for pollination and seed dispersal. They also protect plants from damage caused by UV and visible light. A number of factors and signals influence the accumulation of pigments includes light, temperature, hormones etc. With regard to that of horticultural perspectives, several orchard management practices found to influence better coloration in fruits.