Alterations in polyphenol oxidase activity during organ redifferentiation in carrot calluses cultured in vitro

Abstract

A significant increase in polyphenol oxidase activity occurs in carrot calluses just before or simultaneously with root redifferentiation from the tissue culture cells. The enhancement of polyphenol oxidase activity inherent in redifferentiation (root formation) from calluses is mainly dependent on the appearance of other kinds of polyphenol oxidase which are not detected in calluses unless accompanying redifferentiation. Investigation using agents which have stimulatory, inhibitory, or repressive effects on redifferentiation shows that the elevation of oxidase activity is closely related to the organ forming capacity of carrot calluses.