Abstract
Embryo sensitivity to abscisic acid (ABA) of wheat cultivars “Lancer”, “Horoshirl”, and “Lewis”, which showed different sprouting resistance, was estimated In the initial stage of germination in terms of lipase-esterase activity detected by the fluorescein dibutyrate (FDB) method. Lipase-esterase activity increased in the endosperm adjacent to the epithelium of the scutellum and expanded to the inner area of the endosperm as germination proceeded. Seed germination and lipase-esterase synthesis of sproutingresistant “Lancer” were inhibited by ABA, while sprouting-susceptible “Lewis” was not suppressed in terms of either germination or enzyme synthesis by ABA. In moderately reslstant “Horoshiri”, germination was suppressed, but its lipase-esterase synthesis was not suppressed by ABA Seed of “Lancer” that had been stored for six months after harvest and had lost their dormancy still maintained embryo sensitivity to ABA. The experiments showed that embryo sensitivity to ABA can be estimated with the FDB method by treating whole seeds with ABA, after seeds have lost their dormancy.
