Q. 29 What modification is done on the Ti-plasmid of Agrobacterium tumefaciens to convert it into a cloning vector?
The plasmid is disarmed by deleting the tumour inducing genes in the plasmid. So, that it become an effective cloning vector. The modified tumour inducing (Ti) plasmid of Agrobacterium tumefaciens will no longer remain pathogenic to the plants but still deliver genes of interest into a variety of plants.