Embryos isolated from dormant seeds of apple were cultured in light in the presence of jasmonic acid (JA, 20 μM) for 7 days in parallel to control non-treated ones. H2O2 and ABA levels were quantified and antioxidant enzymes namely, superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) activities were determined in the embryos during the culture. JA treatment stimulated the germination of embryos and activities of SOD, CAT and GR. JA treatment also increased the H2O2 levels on day 1 of embryo culture. In contrast, JA inhibited the levels of ABA during the first 3 days of culture, after that increase in the levels of ABA was observed. Simultaneous increase in H2O2 and a decrease in ABA levels were also observed during the culture. The results suggest the induction of oxidative stress by JA and a signalling role of JA in the breakage of embryonic dormancy is postulated.
Apple, embryos, germination, jasmonic acid, oxidative stress
