Effects of mechanical Injury, cotyledon elimination and nutrition for the germination of apple seeds (Malus pulmila var. domestica)

When dehulled apple seeds (Malus pilmila var. domestica) were induced to germinate, the rate of germination, which was increased by piercing both the radicle and cotyledon, was related to the site of injury. Also, the germination rates of an embryo with ¾ cotyledon (¾ CE), embryo with ½ cotyledon (½ CE), embryo with ¼ cotyledon (¼ CE), and embryo without cotyledon (NCE) gradually decreased compared to an embryo with a normal cotyledon, but it significantly recovered on the agar media containing MS solution and/or 80 mg/L gibberellin (GA3) as nutrition. The results show that the germination of the embryo was inhibited by the partial removal of cotyledon and also demonstrated that the rate of germination could be significantly increased by adding GA3 (80 mg/L) and/or MS medium.