Phytochrome Levels Assayed by in vivo Spectrophotometry in Modified Underground Stems and Storage Roots

Publisher Website
Google Scholar
Abstract
In vivo spectrophotometric assays were conducted with sections of plant material cut from modified stems and storage roots. Phytochrome levels are highest in sections associated with growth such as buds and cambial regions. Interior tissues of tubers and the scale leaves of bulbs which are storage tissue contain low or no detectable phytochrome. However, in the storage root of Pastinaca saliva L. phytochrome is distributed in both the phloem and central regions, though it is highest in the cambial region. Total phytochrome in Gladiolus corm buds exposed to 5 minutes of red light followed by approximately 24 hours of darkness decreases more than 60 per cent. This rapid loss of detectable phytochrome in Gladiolus corm buds resembles phytochrome destruction in etiolated seedlings.