Efficient induction of hairy roots in Tagetes patula L.

We carried out a genetic transformation of leaf explants of Tagetes patula L. using Agrobacterium rhizogenes strains (A-4b, 15834 and 8196RT). An effective way of genetic transformation of T patula is the co-cultivation of sterile leaf explants with a suspension of soil agrobacteria, diluted in Murashige-Skoog medium. The duration of co-cultivation of the explants and the agrobacterial suspension, which ensured effective transformation, was 24 hours, followed by transfer to MS medium containing 20-25 g l(-1) of sucrose. Hairy roots formed after 14 days of cultivation. The frequency of transformation was 85%. The wild A. rhizogenes strain 8196RT was the most productive for obtaining a stably growing culture of hairy roots.