Marigold (Tagetes erecta) is an Asteraceous plant of industrial, ornamental and medicinal importance. Tagetes erecta species, popularly known as marigold, is grown as ornamental plant and is adapted to several agro climates. Inflorescences have been utilized as pigment source for food coloring, mainly of poultry skin and eggs. Lutein is the main pigment in marigold flowers. Some carotenoids are well known as provitamin A compounds. There are many reports on carotenoids and their effect on the prevention of certain ocular diseases, ischemic heart disease, strokes, photoprotection, immune response, aging and cancer. Marigold flowers are certainly a good source of carotenoids; they show very different pigmentation levels. This chapter describes the establishment of techniques for plant regeneration, gene expression, pigment extraction and pigment deposition in specific structures of marigold.