Effets de l'acide gibbérellique et de la kinétine sur le développement de l'activitéα‐amylasique durant la croissance de l'Orge

Effects of gibberellic acid and kinetic on α-amylase production during the germination of barley. - The action of gibberellic acid and kinetin, alone or combined at different concentrations, has been studied on α-amylase production in whole barley seedlings and in embryoless endosperms in course of the six first days of development in the dark. The classic activation of α-amylase synthesis by gibberellic acid has been confirmed both in whole seeds and in embryoless endosperms. Kinetin inhibits α-amylase synthesis after the third day of germination but has no effect on isolated endosperms. When gibberellic acid and kinetin are given simultaneously gibberellic acid stimulated during the three first days just as it does alone, kinetin inhibits after the third day also as it was alone so that the two regulators act, without interactions, at different stages in the time. These effects of kinetin are be independent. A critical examination of the techniques used in the literature in the stud of amylase is made.