In present thesis, The plant materials used were the apple dwarfing self-rooted rootstocks M9, M26, MM106, GM256, SH6. In our study, Leaf water potential(ψ), photosynthetic indexes, hydraulic characteristics and the expression of PIPs(MpPIP1:1, MpPIP2:1), TIPs(MpTIP1:1, MpTIP2:1, MpTIP2:2)were measured. The relative expressions of mRNA encoding five putative aquaporins were determined by Q-RT-PCR. Meanwhile, two different salt tolerance varieties, Malus zumi Rehd. and Malus baccata Borkh. were used as plant...