EFFECT OF ABSCISIC ACID AND KINETIN ON ENZYME ACTIVITIES DURING PETAL SENESCENCE IN CUT CARNATION FLOWERS

Abstract

The effect of abscisic acid (ABA) on the content of protein and a-amino nitrogen and on the activities of enzymes such as catalase, peroxidase, alkaline inorganic pyrophosphatase (PPase), and adenosine triphosphatase (ATPase) during petal senescence gives an insight into the regulation mechanisms operating in leafy and leafless systems. In leafy flowering shoots held either in the light or in darkness, ABA retards petal senescence by reducing the loss of total protein, by decreasing the activities of enzymes such as catalase, alkaline PPase and ATPase, and by favoring the accumulation of peroxidase and α-amino nitrogen. However, these changes were found to be opposite in leafless flowering shoots. Kinetin delayed petal senescence by affecting the changes in protein and a-amino nitrogen content as well as in enzyme activities.