Abscisic and gibberellic acid in growing potato tubers

Summary The content and distribution of absicisic acid (ABA) and gibberellic acid (GA) in potato tubers differing in growth rates and sizes has been determined. No significant correlation has been found between the growth rate and the concentration of ABA and GA in tuber tissue, but the phytohormone content per tuber increased proportionally with tuber size. GA was distributed fairly uniformly throughout the tissue whereas ABA tended to be concentrated in the tuber apex.