Photocontrol of Anthocyanin Synthesis: V. Further Evidence against the Involvement of Photosynthesis in High Irradiance Reaction Anthocyanin Synthesis of Young Seedlings.

Streptomycin and chloramphenicol inhibit the development of the photosynthetic apparatus and enhance anthocyanin synthesis in tomato (Lycopersican esculentum, cv. Beefsteak) and red cabbage (Brassica oleracea, cv. Red Acre) seedlings. The two antibiotics do not affect the basic features of light-dependent anthocyanin formation: the relative effectiveness of different irradiance levels and of different spectral regions and the red-far red reversibility of the response are essentially the same in seedlings grown in water or in solution of the two antibiotics. The action of the two antibiotics on anthocyanin synthesis is probably independent of the action of light. The results provide further evidence that the role played by photosynthesis in high irradiance reaction anthocyanin synthesis of young seedlings is only a minor one, if at all.