Abstract:To determine the effect of silver nitrate on genetic transformation, Agrobocrerium tumefaciens-mediated 1eaves of Morus alba cv. Shiniehinose were used as explants cultured on kanamycin-resistant screening medium (MS basal medium supplemented with 200-400 mg L-1 carbenicillin and 30-40 mg L-1 kanamycin)，to which 2 mg L-1 silver nitrate was added．The results showed that the rate of browning leaf discs infected with Agrobacterium tumefaciens strain LBA4404 decreaced by 7.2％ ，regeneration frequency of kanamycin-resistant buds increased by 3.9％ , transformation frequency of Gly gene increased by 9.6％, and the false positive transformants as detected by PCR decreased by 42.5％．The experiments demonstrated that silver narrate had inhibiting effect on the growth of strain LBA4404，which might increase transfonnation frequency in white mulberry.