ANALYSIS OF LIGHT‐CONTROLLED ANTHOCYANIN FORMATION IN COLEOPTILES OF Zea mays L.: THE ROLE OF UV‐B, BLUE, RED AND FAR‐RED LIGHT

Abstract

Abstract— Light‐induced anthocyanin formation in Zea mays L. coleoptiles was investigated in seven different varieties of this species. Under the test conditions, four varieties showed practically no response to any waveband used (UV, continuous red and continuous far‐red), two responded strongly to both UV and far‐red, and one showed a strong response only to far‐red. The radiation‐sensitive varieties showed, however, only a very weak response to continuous red light. In those varieties sensitive to far‐red light, a pretreatment with continuous red light led to a greatly enhanced response to UV or in one case the manifestation of a response to UV that was previously lacking. Further investigations in one radiation‐sensitive variety (INRA) showed that the UV response was to UV‐B radiation below 350 nm. The UV response, as well as the far‐red and blue responses in this variety, showed fluence‐rate dependency. Red light was almost ineffective and showed only a very weak fluence‐rate dependency.