PHOTOINDUCTION OF ANTHOCYANIN IN MAIZE - A GENETIC APPROACH

The pathway of anthocyanin biosynthesis is well known while its regula tion is less characterized. In this paper we focus our attention on th e process of anthocyanin photoinduction. The results obtained followin g irradiation of seedling root tissues with lights of different qualit y disclose a significant response to blue light, apparently not attrib utable to phytochrome action. Even when anthocyanin accumulation is si gnificantly increased because of the presence of Pl, a pigment intensi fier, the total phytochrome content is not affected. The blue light ef fect is general in the sense that is observed in all genetic backgroun ds tested. Photoinduction of anthocyanin accumulation in viviparous mu tants blocked in carotenogenesis depends on blue light indicating that carotenoids are not involved in the blue response. Studies with calci um-channel blockers and calcium antagonists seem to exclude a requirem ent of Ca++ as an intermediary component of the light transduction pat hway.