Effects of IAA on callose content and callose synthase activity. A IAA content in the rootstock of the grafted junction of different grafting combinations 25 days after grafting. B Effects of exogenous treatment with IAA in the root of compatible combination (CG) on IAA content in the rootstock of the grafted junction. C Effects of exogenous treatment with IAA in the root of CG on callose content in the rootstock of the grafted junction. D Effects of exogenous treatment with IAA in the root of CG on callose synthase activity in the rootstock of the grafted junction. E Effects of exogenous treatment with TIBA in the root of the incompatible combination (IG) on IAA content in the rootstock of the grafted junction. F Effects of exogenous treatment with TIBA in the root of IG on callose content in the rootstock of the grafted junction. G Effects of exogenous treatment with TIBA in the root of IG on callose synthase activity in the rootstock of the grafted junction. Nineteen days after grafting, 10 μM IAA or TIBA was applied and the IAA content, callose content, and callose synthase activity were measured after treatment for 6 days. Data represent the mean ± standard deviation (n = 3). According to Tukey’s test, means with the same letter did not differ significantly at P < 0.05. FW, fresh weight; NG, non-grafted; SG, self-grafted.