The isopenteryl transferase ( ipt ) gene from Agrobacterium tumefaciens (Smith et Townsend) Conn was driven under the tobacco TA29 promoter and introduced into tobacco (Nicotiana tabacum L.) plants by A. tumefaciens mediated transformation. PCR and Southern blot analysis confirmed that the ipt gene has integrated into the genomes of tobacco plants. The expression pattern of this chimeric TA29_ ipt gene in the transgenic plants was studied, and the endogenous cytokinin level in different organs was assayed by ELISA method. The results showed that the cytokinin content in the androecium of transgenic plants increased 3-4 times as compared with the control, and some changes of the fertility of the TA29_ ipt transgenic plants have been observed.
