Effect of Ga₃, Aba and Ck on Biosynthesis of Lipids in the Kernels of Almond (Prunus Amygdalus Batsch)

Gibberellic acid enhanced incorporation of labelled acetate into total lipids in almond kernels at 70 DAF; the stage of maximum rate of lipid synthesis. Abscissic acid, as well as cytokinin, on the other hand, inhibited lipid synthesis at this stage. Abscissic acid increased the relative ¹⁴C-incorporation into polar lipid fraction significantly at 5 and 10 ppm concentrations and decreased the incorporation into triacyl-glycerols. Cytokinin also reduced the relative proportion of label into triacylglcerols by a compensatory increase in partial glycerides and free fatty acids. Amongst polar fraction, abscissic acid decreased the relative ¹⁴C-incorporation into phosphatidyl inositol (PI) with a corresponding increase in diphosphatidyl glycerol (DPG). Gibberellic acid increased the synthesis of phosphatidyl choline while cytokinin (15 ppm) decreased that of PI without appreciably influencing other polar lipid fractions.