Three factor design of experiment were conducted to investigate the effects of germination time of
tomato seeds, Agrobacterium rhizogenes strains and the bacterial cell density on induction rate of tomato hairy roots.
All the combination of three factors could induce hairy roots. The results of PCR detection on hairy roots indicated
that rolB gene in Ri plasmid of A. rhizogenes was integrated into the genome of tomato cell successfully. The results
suggested that all of the three factors influenced the induction rate of hairy roots significantly, and there were
interactive effects among different factors. The highest induction rate of hairy root was 58.8%, and it occurred when
tomato cotyledon was infected by A. rhizogenes strain ATCC15834 with a bacterial cell density of 0.4-0.6 at OD600
after 8-12 d of germination. This combination might be the optimal condition for the induction of tomato hairy roots. |