Action of light on accumulation of carotenoids and chlorophylls in the milo shoot (Sorghum vulgarePers.)

✍ Scribed by K. Malhotra; H. Oelze-Karow; H. Mohr

• Publisher: Springer-Verlag
• Year: 1982
• Tongue: English
• Weight: 916 KB
• Volume: 154
• Category: Article
• ISSN: 0032-0935
• DOI: 10.1007/bf00393916

✦ Synopsis

We have performed a comprehensive study on the mechanism of regulation of carotenogenesis by light in the shoot of Sorghum vulgare. Our work shows that carotenoid accumulation is simultaneously controlled by phytochrome (Pfr) and by the availability of chlorophyll. Throughout plastidogenesis light dependent chlorophyll and carotenoid accumulation are interdependent processes: Accmnulation of chlorophyll in natural light requires the presence of carotenoids; likewise, accumulation of considerable amounts of carotenoids depends on the availability of chlorophyll. However, in both cases the efficiency of the biosynthetic pathway, the poten tial biosynthetic rates (" capacities") are determined by phytochrome. A "push and pull" model of carotenogenesis advanced previously (Frosch and Mohr 1980, Planta 148, 279) to explain carotenogenesis in the mustard (Sinapis alba) seedling also applies to the monocotyledonous milo (Sorghum vulgate) seedling. Therefore, we suggest that the model applies to carotenogenesis in higher plants in general.