Diverse effects of uniconazole and nicotinamide on germination, growth, endogenous hormones and some enzymic activities of peas

ABSTRACT

Pea seeds were soaked in different solutions of uniconazole or nicotinamide for 24 hours. The effects of such treatment on germination of these seeds and some growth parameters of the given plants concomitant with the changes in the hormonal contents and activities of IAA oxidase, amylase and proteinase were investigated. Uniconazole was found to retard the rate germination of the seeds and retard the elongation of stems accompanied with increases in the number of their lateral branches and stem thickness, but decreases the number of leaves and their area per plant leading to reduction in both fresh and dry weights of shoots and roots. These aspects were accompanied with clear reduction in the contents and levels of cytokinins, ABA and activity of IAA oxidase. In the same time the activities of amylase and proteinase were reduced. All these physiological phenomena were proportional to the concentration of uniconazole. On the other hand, nicotinamide caused diverse effects on the previously mentioned physiological phenomena as compared with those caused by the corresponding concentrations of uniconazole. This was accompanied by regular picture of hormone contents and complete disappearance of ABA, and these effects were proportional to nicotinamide concentrations. In all cases the endogenous hormonal picture coordinated with the different physiological changes studied