Abstract
We constructed new λTI phage vectors, λTI3, λTI4, λTI5 and λTI6, which were automatically convertible into Ti-plasmid binary vectors by using the Cre-lox site-specific recombination system of bacteriophage P1. Hygromycin B phosphotransferase (HPT) gene was inserted in the T-DNA region of these λTI vectors as a plant selectable maker. Tobacco plants, which were transformed by Agrobacterium containing the Tiplasmids resulted from the automatic conversion of the λTI vectors, could be tightly selected by hygromycin B. This λTI system will certainly provide a powerful tool for genetic complementation test of candidate genes obtained by positional cloning.
