Blue light mediated regulation of β-amylase activity in mustard (sinapis alba l.) cotyledons

Abstract

In the cotyledons of mustard (Sinapis alba L.) seedlings grown under continuous blue light, β-amylase activity increased between 42-96 h from sowing and thereafter the β-amylase activity abruptly declined. Preirradiation with blue light did not increase the responsivity of the subsequent phytochrome-mediated β-amylase increase in the cotyledons. The run-off kinetics of β-amylase increase in seedlings transferred from blue light to darkness indicated that the components of the blue light-triggered signal chain are kinetically identical to those of the phytochrome-mediated signal chain. Far-red reversibility experiments showed that the above blue light response is either mediated by phytochrome directly or the blue light photoreceptor requires the coaction of phytochrome. © 1988. The Japanese Society of Plant Physiologists.