Abstract: Taking leaves from the vitro cuttings of Pyrus communis L. ‘Bartlett’, P. pyrifolia Nak.‘Shenbuzhi’and P. bretschneideri Rhed. ‘Zaosu’as explants, the adventitious bud were induced, propagated, and rooted. The effects of basic media, plant growth regulators and their concentration, AgNO₃ with
different concentration and the ratios of the nitrate: ammonium on adventitious bud regeneration were studied.The results showed that the best bud regeneration medium from leaves of‘Bartlett’wasMS + TDZ 0.5 mg/L+ IBA 0.1 mg/L. The bud regeneration rate of ‘Shenbuzhi’ and ‘Zaosu’ respectively from leaves was reached 89.6% and 81.2% , with an average regeneration buds of 3.45 and 3.73 on QL + TDZ 1.0 mg/L +NAA 0.1 mg/L after three weeks dark pretreatment. The bud regeneration frequency of‘Shenbuzhi’from
leaves was enhanced on medium containing AgNO₃ 0.1 - 4.0 mg/L, 1∶2 - 7 of the nitrate: ammonium with K+ 21.50 mmol/L, while inhibited without nitrate; The subculture medium for in vitro proliferation of three cultivars was MS +BA 1.0 mg/L + IBA 0.1 mg/L; The rooting rate in varying degrees was obtained in the media of MS, 1 /4MS supplemented with IBA at 1.0 - 2.5 mg/L and sucrose at 5 - 15 g/L and AC ( actived charcoal) at 0.5 - 1.0 g/L.

Key words: Pear, Leaf, Regeneration, Tissue culture