Establishment of Agrobacterium rhizogenes-mediated tobacco genetic transformation system

Tobacco (Nicotiana tabacum L.) is an important economic crop. Agrobacterium rhizogenes can induce the production of hairy roots in plants after infestation. However, no study has reported the induction of hairy roots and regeneration of plants from tobacco seedlings grown in soil. This study used Agrobacterium rhizogenes A4, 15834, K599, and R1601 to induce tobacco K326 soil seedlings to investigate the induction efficiency of Agrobacterium rhizogenes on cotyledons and hypocotyls. Regenerable roots were selected from the induced hairy roots for culture, and the regenerated plants were obtained after 60 days. Results showed that the induction rate of hairy roots was up to 81.33% after A4 infection of tobacco explant stems. While R1601 had a relatively low induction rate of 24.33%. Agrobacterium strain A4, suitable for inducing hairy roots in tobacco, was screened. The hairy roots of tobacco were white with abundant root hairs and could grow rapidly on solid medium without exogenous hormones. Moreover, regenerated plants with hairy roots of tobacco were obtained, and the regeneration rate was 80%. In addition, A4 could transfer T-DNA containing Ri plasmids into the explants. The results of PCR showed that rolB gene was stably expressed in tobacco hairy root genome with a 50% co-transformation frequency. The study implied that the hairy root regenerative plants could be induced by using tobacco soil culture seedlings. © (2023), (Bio Tech System). All Rights Reserved.