Interaction of jasmonic and abscisic acid in the control of lipases and proteases in germinating apple embryos

Effects of jasmonic (JA) and abscisic (ABA) acid on the activities of lipases and proteases were studied in cultured embryos excised from apple seeds. JA stimulated alkaline (AlkL) and acid (AcL) lipases as well as proteases hydrolyzing casein, L‐cystine‐di‐β‐naphthylamide (CysβNa), glycyl‐glycyl‐glycine (GlyGlyGly) and native apple seed proteins. ABA inhibited AlkL and protease activities, with the exception of the hydrolysis of native proteins which was stimulated. The activity of AcL was not affected by ABA. AlkL was affected by JA and ABA also in vitro. An antagonistic interaction between JA and ABA on all studied enzyme activities. except CysβNa hydrolyzing protease, was observed. The positions of JA‐ and ABA‐controlled sites in the metabolic regulation of the removal of embryonal dormancy in apple seeds are discussed.