Engineered gray mold resistance, antioxidant capacity, and pigmentation in betalain-producing crops and ornamentals

Significance In plants, three major classes of pigments are generally responsible for colors seen in fruits and flowers: anthocyanins, carotenoids, and betalains. Betalains are red-violet and yellow plant pigments that have been reported to possess strong antioxidant and health-promoting properties, including anticancer, antiinflammatory, and antidiabetic activity. Here, heterologous betalain production was achieved for the first time in three major food crops: tomato, potato, and eggplant. Remarkably, betalain production in tobacco resulted in significantly enhanced resistance toward gray mold ( Botrytis cinerea ), a plant pathogen responsible for major crop losses. Considering the significant characteristics of these molecules, heterologous betalain production now offers exciting opportunities for creating new value for consumers, producers, and suppliers of food crops and ornamental plants.