Light Control of Anthocyanin Biosynthesis in Zea Seedlings

Evidence for involvement of two non‐photosynthetic pigments in photoinduction of anthocyanin biosynthesis in the roots and mesocotyls of Zea mays L. seedlings is presented. Short (5 min), low energy (4.5 × 10 3 J m −2 ) fluences of red light neither induced anthocyanin synthesis nor enhanced phenylalanine ammonia‐lyase activity in dark‐grown maize seedlings. Little anthocyanin synthesis and no enhancement of phenylalanine ammonia‐lyase activity was induced by continuous far‐red light. Continuous white or blue light induced both anthocyanin synthesis and enhanced phenylalanine ammonia‐lyase activity. These results show that phytochrome alone cannot induce anthocyanin synthesis in maize seedlings. However, a strong phytochrome mediation of white light induced pigment synthesis was demonstrated. This effect was not demonstrable with white light enhanced phenylalanine ammonia‐lyase activity, indicating that phytochrome controls another step in anthocyanin biosynthesis.