Time dependence of phytochrome-mediated carotenoid and chlorophyll synthesis in Sorghum bicolor L

Abstract

In 5 - day - old etiolated Sorghum seedlings, red light irradiation for 1 s enhanced carotenoid and chlorophyll accumulation, and 5 min of red light treatment saturated the photoresponse. The degree of red/far - red photoreversibility of carotenoid accumulation was dependent on the age of the plant. No significant escape from far - red reversibility was observed up to 30 min after the onset of a saturating red light pulse in 5 - day - old etiolated seedlings. Thereafter, the escape was relatively fast and completed within 180 min.